From: Kazuki Hashimoto Date: Wed, 24 May 2023 14:56:36 +0000 (+0900) Subject: kernel: 6.1: Synchronize MGLRU patches with upstream X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=b28b8ed1f45de1ecff0a893345a0fcbf3fff3bbe;p=openwrt%2Fstaging%2Fhauke.git kernel: 6.1: Synchronize MGLRU patches with upstream Replace the refreshed 5.15 backports with backports for 6.1. This fixes FMODE_CAN_ODIRECT having the same value as FMODE_NOREUSE. Signed-off-by: Kazuki Hashimoto --- diff --git a/target/linux/generic/backport-6.1/020-v6.3-01-UPSTREAM-mm-multi-gen-LRU-rename-lru_gen_struct-to-l.patch b/target/linux/generic/backport-6.1/020-v6.3-01-UPSTREAM-mm-multi-gen-LRU-rename-lru_gen_struct-to-l.patch new file mode 100644 index 0000000000..d63b03e6e8 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-01-UPSTREAM-mm-multi-gen-LRU-rename-lru_gen_struct-to-l.patch @@ -0,0 +1,363 @@ +From 8c20e2eb5f2a0175b774134685e4d7bd93e85ff8 Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Wed, 21 Dec 2022 21:18:59 -0700 +Subject: [PATCH 01/19] UPSTREAM: mm: multi-gen LRU: rename lru_gen_struct to + lru_gen_folio + +Patch series "mm: multi-gen LRU: memcg LRU", v3. + +Overview +======== + +An memcg LRU is a per-node LRU of memcgs. It is also an LRU of LRUs, +since each node and memcg combination has an LRU of folios (see +mem_cgroup_lruvec()). + +Its goal is to improve the scalability of global reclaim, which is +critical to system-wide memory overcommit in data centers. Note that +memcg reclaim is currently out of scope. + +Its memory bloat is a pointer to each lruvec and negligible to each +pglist_data. In terms of traversing memcgs during global reclaim, it +improves the best-case complexity from O(n) to O(1) and does not affect +the worst-case complexity O(n). Therefore, on average, it has a sublinear +complexity in contrast to the current linear complexity. + +The basic structure of an memcg LRU can be understood by an analogy to +the active/inactive LRU (of folios): +1. It has the young and the old (generations), i.e., the counterparts + to the active and the inactive; +2. The increment of max_seq triggers promotion, i.e., the counterpart + to activation; +3. Other events trigger similar operations, e.g., offlining an memcg + triggers demotion, i.e., the counterpart to deactivation. + +In terms of global reclaim, it has two distinct features: +1. Sharding, which allows each thread to start at a random memcg (in + the old generation) and improves parallelism; +2. Eventual fairness, which allows direct reclaim to bail out at will + and reduces latency without affecting fairness over some time. + +The commit message in patch 6 details the workflow: +https://lore.kernel.org/r/20221222041905.2431096-7-yuzhao@google.com/ + +The following is a simple test to quickly verify its effectiveness. + + Test design: + 1. Create multiple memcgs. + 2. Each memcg contains a job (fio). + 3. All jobs access the same amount of memory randomly. + 4. The system does not experience global memory pressure. + 5. Periodically write to the root memory.reclaim. + + Desired outcome: + 1. All memcgs have similar pgsteal counts, i.e., stddev(pgsteal) + over mean(pgsteal) is close to 0%. + 2. The total pgsteal is close to the total requested through + memory.reclaim, i.e., sum(pgsteal) over sum(requested) is close + to 100%. + + Actual outcome [1]: + MGLRU off MGLRU on + stddev(pgsteal) / mean(pgsteal) 75% 20% + sum(pgsteal) / sum(requested) 425% 95% + + #################################################################### + MEMCGS=128 + + for ((memcg = 0; memcg < $MEMCGS; memcg++)); do + mkdir /sys/fs/cgroup/memcg$memcg + done + + start() { + echo $BASHPID > /sys/fs/cgroup/memcg$memcg/cgroup.procs + + fio -name=memcg$memcg --numjobs=1 --ioengine=mmap \ + --filename=/dev/zero --size=1920M --rw=randrw \ + --rate=64m,64m --random_distribution=random \ + --fadvise_hint=0 --time_based --runtime=10h \ + --group_reporting --minimal + } + + for ((memcg = 0; memcg < $MEMCGS; memcg++)); do + start & + done + + sleep 600 + + for ((i = 0; i < 600; i++)); do + echo 256m >/sys/fs/cgroup/memory.reclaim + sleep 6 + done + + for ((memcg = 0; memcg < $MEMCGS; memcg++)); do + grep "pgsteal " /sys/fs/cgroup/memcg$memcg/memory.stat + done + #################################################################### + +[1]: This was obtained from running the above script (touches less + than 256GB memory) on an EPYC 7B13 with 512GB DRAM for over an + hour. + +This patch (of 8): + +The new name lru_gen_folio will be more distinct from the coming +lru_gen_memcg. + +Link: https://lkml.kernel.org/r/20221222041905.2431096-1-yuzhao@google.com +Link: https://lkml.kernel.org/r/20221222041905.2431096-2-yuzhao@google.com +Signed-off-by: Yu Zhao +Cc: Johannes Weiner +Cc: Jonathan Corbet +Cc: Michael Larabel +Cc: Michal Hocko +Cc: Mike Rapoport +Cc: Roman Gushchin +Cc: Suren Baghdasaryan +Signed-off-by: Andrew Morton +Bug: 274865848 +(cherry picked from commit 391655fe08d1f942359a11148aa9aaf3f99d6d6f) +Change-Id: I7df67e0e2435ba28f10eaa57d28d98b61a9210a6 +Signed-off-by: T.J. Mercier +--- + include/linux/mm_inline.h | 4 ++-- + include/linux/mmzone.h | 6 +++--- + mm/vmscan.c | 34 +++++++++++++++++----------------- + mm/workingset.c | 4 ++-- + 4 files changed, 24 insertions(+), 24 deletions(-) + +diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h +index e8ed225d8f7ca..f63968bd7de59 100644 +--- a/include/linux/mm_inline.h ++++ b/include/linux/mm_inline.h +@@ -178,7 +178,7 @@ static inline void lru_gen_update_size(struct lruvec *lruvec, struct folio *foli + int zone = folio_zonenum(folio); + int delta = folio_nr_pages(folio); + enum lru_list lru = type * LRU_INACTIVE_FILE; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + + VM_WARN_ON_ONCE(old_gen != -1 && old_gen >= MAX_NR_GENS); + VM_WARN_ON_ONCE(new_gen != -1 && new_gen >= MAX_NR_GENS); +@@ -224,7 +224,7 @@ static inline bool lru_gen_add_folio(struct lruvec *lruvec, struct folio *folio, + int gen = folio_lru_gen(folio); + int type = folio_is_file_lru(folio); + int zone = folio_zonenum(folio); +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + + VM_WARN_ON_ONCE_FOLIO(gen != -1, folio); + +diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h +index 5f74891556f33..bd3e4689f72dc 100644 +--- a/include/linux/mmzone.h ++++ b/include/linux/mmzone.h +@@ -404,7 +404,7 @@ enum { + * The number of pages in each generation is eventually consistent and therefore + * can be transiently negative when reset_batch_size() is pending. + */ +-struct lru_gen_struct { ++struct lru_gen_folio { + /* the aging increments the youngest generation number */ + unsigned long max_seq; + /* the eviction increments the oldest generation numbers */ +@@ -461,7 +461,7 @@ struct lru_gen_mm_state { + struct lru_gen_mm_walk { + /* the lruvec under reclaim */ + struct lruvec *lruvec; +- /* unstable max_seq from lru_gen_struct */ ++ /* unstable max_seq from lru_gen_folio */ + unsigned long max_seq; + /* the next address within an mm to scan */ + unsigned long next_addr; +@@ -524,7 +524,7 @@ struct lruvec { + unsigned long flags; + #ifdef CONFIG_LRU_GEN + /* evictable pages divided into generations */ +- struct lru_gen_struct lrugen; ++ struct lru_gen_folio lrugen; + /* to concurrently iterate lru_gen_mm_list */ + struct lru_gen_mm_state mm_state; + #endif +diff --git a/mm/vmscan.c b/mm/vmscan.c +index d18296109aa7e..27142caf284c1 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -3190,7 +3190,7 @@ static int get_nr_gens(struct lruvec *lruvec, int type) + + static bool __maybe_unused seq_is_valid(struct lruvec *lruvec) + { +- /* see the comment on lru_gen_struct */ ++ /* see the comment on lru_gen_folio */ + return get_nr_gens(lruvec, LRU_GEN_FILE) >= MIN_NR_GENS && + get_nr_gens(lruvec, LRU_GEN_FILE) <= get_nr_gens(lruvec, LRU_GEN_ANON) && + get_nr_gens(lruvec, LRU_GEN_ANON) <= MAX_NR_GENS; +@@ -3596,7 +3596,7 @@ struct ctrl_pos { + static void read_ctrl_pos(struct lruvec *lruvec, int type, int tier, int gain, + struct ctrl_pos *pos) + { +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + int hist = lru_hist_from_seq(lrugen->min_seq[type]); + + pos->refaulted = lrugen->avg_refaulted[type][tier] + +@@ -3611,7 +3611,7 @@ static void read_ctrl_pos(struct lruvec *lruvec, int type, int tier, int gain, + static void reset_ctrl_pos(struct lruvec *lruvec, int type, bool carryover) + { + int hist, tier; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + bool clear = carryover ? NR_HIST_GENS == 1 : NR_HIST_GENS > 1; + unsigned long seq = carryover ? lrugen->min_seq[type] : lrugen->max_seq + 1; + +@@ -3688,7 +3688,7 @@ static int folio_update_gen(struct folio *folio, int gen) + static int folio_inc_gen(struct lruvec *lruvec, struct folio *folio, bool reclaiming) + { + int type = folio_is_file_lru(folio); +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + int new_gen, old_gen = lru_gen_from_seq(lrugen->min_seq[type]); + unsigned long new_flags, old_flags = READ_ONCE(folio->flags); + +@@ -3733,7 +3733,7 @@ static void update_batch_size(struct lru_gen_mm_walk *walk, struct folio *folio, + static void reset_batch_size(struct lruvec *lruvec, struct lru_gen_mm_walk *walk) + { + int gen, type, zone; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + + walk->batched = 0; + +@@ -4250,7 +4250,7 @@ static bool inc_min_seq(struct lruvec *lruvec, int type, bool can_swap) + { + int zone; + int remaining = MAX_LRU_BATCH; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + int new_gen, old_gen = lru_gen_from_seq(lrugen->min_seq[type]); + + if (type == LRU_GEN_ANON && !can_swap) +@@ -4286,7 +4286,7 @@ static bool try_to_inc_min_seq(struct lruvec *lruvec, bool can_swap) + { + int gen, type, zone; + bool success = false; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + DEFINE_MIN_SEQ(lruvec); + + VM_WARN_ON_ONCE(!seq_is_valid(lruvec)); +@@ -4307,7 +4307,7 @@ static bool try_to_inc_min_seq(struct lruvec *lruvec, bool can_swap) + ; + } + +- /* see the comment on lru_gen_struct */ ++ /* see the comment on lru_gen_folio */ + if (can_swap) { + min_seq[LRU_GEN_ANON] = min(min_seq[LRU_GEN_ANON], min_seq[LRU_GEN_FILE]); + min_seq[LRU_GEN_FILE] = max(min_seq[LRU_GEN_ANON], lrugen->min_seq[LRU_GEN_FILE]); +@@ -4329,7 +4329,7 @@ static void inc_max_seq(struct lruvec *lruvec, bool can_swap, bool force_scan) + { + int prev, next; + int type, zone; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + + spin_lock_irq(&lruvec->lru_lock); + +@@ -4387,7 +4387,7 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq, + bool success; + struct lru_gen_mm_walk *walk; + struct mm_struct *mm = NULL; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + + VM_WARN_ON_ONCE(max_seq > READ_ONCE(lrugen->max_seq)); + +@@ -4452,7 +4452,7 @@ static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, unsig + unsigned long old = 0; + unsigned long young = 0; + unsigned long total = 0; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + struct mem_cgroup *memcg = lruvec_memcg(lruvec); + + for (type = !can_swap; type < ANON_AND_FILE; type++) { +@@ -4737,7 +4737,7 @@ static bool sort_folio(struct lruvec *lruvec, struct folio *folio, int tier_idx) + int delta = folio_nr_pages(folio); + int refs = folio_lru_refs(folio); + int tier = lru_tier_from_refs(refs); +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + + VM_WARN_ON_ONCE_FOLIO(gen >= MAX_NR_GENS, folio); + +@@ -4837,7 +4837,7 @@ static int scan_folios(struct lruvec *lruvec, struct scan_control *sc, + int scanned = 0; + int isolated = 0; + int remaining = MAX_LRU_BATCH; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + struct mem_cgroup *memcg = lruvec_memcg(lruvec); + + VM_WARN_ON_ONCE(!list_empty(list)); +@@ -5237,7 +5237,7 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc + + static bool __maybe_unused state_is_valid(struct lruvec *lruvec) + { +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + + if (lrugen->enabled) { + enum lru_list lru; +@@ -5519,7 +5519,7 @@ static void lru_gen_seq_show_full(struct seq_file *m, struct lruvec *lruvec, + int i; + int type, tier; + int hist = lru_hist_from_seq(seq); +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + + for (tier = 0; tier < MAX_NR_TIERS; tier++) { + seq_printf(m, " %10d", tier); +@@ -5569,7 +5569,7 @@ static int lru_gen_seq_show(struct seq_file *m, void *v) + unsigned long seq; + bool full = !debugfs_real_fops(m->file)->write; + struct lruvec *lruvec = v; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + int nid = lruvec_pgdat(lruvec)->node_id; + struct mem_cgroup *memcg = lruvec_memcg(lruvec); + DEFINE_MAX_SEQ(lruvec); +@@ -5823,7 +5823,7 @@ void lru_gen_init_lruvec(struct lruvec *lruvec) + { + int i; + int gen, type, zone; +- struct lru_gen_struct *lrugen = &lruvec->lrugen; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + + lrugen->max_seq = MIN_NR_GENS + 1; + lrugen->enabled = lru_gen_enabled(); +diff --git a/mm/workingset.c b/mm/workingset.c +index ae7e984b23c6b..688aaa73f64e8 100644 +--- a/mm/workingset.c ++++ b/mm/workingset.c +@@ -223,7 +223,7 @@ static void *lru_gen_eviction(struct folio *folio) + unsigned long token; + unsigned long min_seq; + struct lruvec *lruvec; +- struct lru_gen_struct *lrugen; ++ struct lru_gen_folio *lrugen; + int type = folio_is_file_lru(folio); + int delta = folio_nr_pages(folio); + int refs = folio_lru_refs(folio); +@@ -252,7 +252,7 @@ static void lru_gen_refault(struct folio *folio, void *shadow) + unsigned long token; + unsigned long min_seq; + struct lruvec *lruvec; +- struct lru_gen_struct *lrugen; ++ struct lru_gen_folio *lrugen; + struct mem_cgroup *memcg; + struct pglist_data *pgdat; + int type = folio_is_file_lru(folio); +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-02-UPSTREAM-mm-multi-gen-LRU-rename-lrugen-lists-to-lru.patch b/target/linux/generic/backport-6.1/020-v6.3-02-UPSTREAM-mm-multi-gen-LRU-rename-lrugen-lists-to-lru.patch new file mode 100644 index 0000000000..65fb0144b1 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-02-UPSTREAM-mm-multi-gen-LRU-rename-lrugen-lists-to-lru.patch @@ -0,0 +1,208 @@ +From 656287d55d9cfc72a4bcd4d9bd098570f12ce409 Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Wed, 21 Dec 2022 21:19:00 -0700 +Subject: [PATCH 02/19] UPSTREAM: mm: multi-gen LRU: rename lrugen->lists[] to + lrugen->folios[] + +lru_gen_folio will be chained into per-node lists by the coming +lrugen->list. + +Link: https://lkml.kernel.org/r/20221222041905.2431096-3-yuzhao@google.com +Signed-off-by: Yu Zhao +Cc: Johannes Weiner +Cc: Jonathan Corbet +Cc: Michael Larabel +Cc: Michal Hocko +Cc: Mike Rapoport +Cc: Roman Gushchin +Cc: Suren Baghdasaryan +Signed-off-by: Andrew Morton +Bug: 274865848 +(cherry picked from commit 6df1b2212950aae2b2188c6645ea18e2a9e3fdd5) +Change-Id: I09f53e0fb2cd6b8b3adbb8a80b15dc5efbeae857 +Signed-off-by: T.J. Mercier +--- + Documentation/mm/multigen_lru.rst | 8 ++++---- + include/linux/mm_inline.h | 4 ++-- + include/linux/mmzone.h | 8 ++++---- + mm/vmscan.c | 20 ++++++++++---------- + 4 files changed, 20 insertions(+), 20 deletions(-) + +diff --git a/Documentation/mm/multigen_lru.rst b/Documentation/mm/multigen_lru.rst +index d7062c6a89464..d8f721f98868a 100644 +--- a/Documentation/mm/multigen_lru.rst ++++ b/Documentation/mm/multigen_lru.rst +@@ -89,15 +89,15 @@ variables are monotonically increasing. + + Generation numbers are truncated into ``order_base_2(MAX_NR_GENS+1)`` + bits in order to fit into the gen counter in ``folio->flags``. Each +-truncated generation number is an index to ``lrugen->lists[]``. The ++truncated generation number is an index to ``lrugen->folios[]``. The + sliding window technique is used to track at least ``MIN_NR_GENS`` and + at most ``MAX_NR_GENS`` generations. The gen counter stores a value + within ``[1, MAX_NR_GENS]`` while a page is on one of +-``lrugen->lists[]``; otherwise it stores zero. ++``lrugen->folios[]``; otherwise it stores zero. + + Each generation is divided into multiple tiers. A page accessed ``N`` + times through file descriptors is in tier ``order_base_2(N)``. Unlike +-generations, tiers do not have dedicated ``lrugen->lists[]``. In ++generations, tiers do not have dedicated ``lrugen->folios[]``. In + contrast to moving across generations, which requires the LRU lock, + moving across tiers only involves atomic operations on + ``folio->flags`` and therefore has a negligible cost. A feedback loop +@@ -127,7 +127,7 @@ page mapped by this PTE to ``(max_seq%MAX_NR_GENS)+1``. + Eviction + -------- + The eviction consumes old generations. Given an ``lruvec``, it +-increments ``min_seq`` when ``lrugen->lists[]`` indexed by ++increments ``min_seq`` when ``lrugen->folios[]`` indexed by + ``min_seq%MAX_NR_GENS`` becomes empty. To select a type and a tier to + evict from, it first compares ``min_seq[]`` to select the older type. + If both types are equally old, it selects the one whose first tier has +diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h +index f63968bd7de59..da38e3d962e2f 100644 +--- a/include/linux/mm_inline.h ++++ b/include/linux/mm_inline.h +@@ -256,9 +256,9 @@ static inline bool lru_gen_add_folio(struct lruvec *lruvec, struct folio *folio, + lru_gen_update_size(lruvec, folio, -1, gen); + /* for folio_rotate_reclaimable() */ + if (reclaiming) +- list_add_tail(&folio->lru, &lrugen->lists[gen][type][zone]); ++ list_add_tail(&folio->lru, &lrugen->folios[gen][type][zone]); + else +- list_add(&folio->lru, &lrugen->lists[gen][type][zone]); ++ list_add(&folio->lru, &lrugen->folios[gen][type][zone]); + + return true; + } +diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h +index bd3e4689f72dc..02e4323744715 100644 +--- a/include/linux/mmzone.h ++++ b/include/linux/mmzone.h +@@ -312,7 +312,7 @@ enum lruvec_flags { + * They form a sliding window of a variable size [MIN_NR_GENS, MAX_NR_GENS]. An + * offset within MAX_NR_GENS, i.e., gen, indexes the LRU list of the + * corresponding generation. The gen counter in folio->flags stores gen+1 while +- * a page is on one of lrugen->lists[]. Otherwise it stores 0. ++ * a page is on one of lrugen->folios[]. Otherwise it stores 0. + * + * A page is added to the youngest generation on faulting. The aging needs to + * check the accessed bit at least twice before handing this page over to the +@@ -324,8 +324,8 @@ enum lruvec_flags { + * rest of generations, if they exist, are considered inactive. See + * lru_gen_is_active(). + * +- * PG_active is always cleared while a page is on one of lrugen->lists[] so that +- * the aging needs not to worry about it. And it's set again when a page ++ * PG_active is always cleared while a page is on one of lrugen->folios[] so ++ * that the aging needs not to worry about it. And it's set again when a page + * considered active is isolated for non-reclaiming purposes, e.g., migration. + * See lru_gen_add_folio() and lru_gen_del_folio(). + * +@@ -412,7 +412,7 @@ struct lru_gen_folio { + /* the birth time of each generation in jiffies */ + unsigned long timestamps[MAX_NR_GENS]; + /* the multi-gen LRU lists, lazily sorted on eviction */ +- struct list_head lists[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; ++ struct list_head folios[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; + /* the multi-gen LRU sizes, eventually consistent */ + long nr_pages[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; + /* the exponential moving average of refaulted */ +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 27142caf284c1..b02fed912f742 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -4258,7 +4258,7 @@ static bool inc_min_seq(struct lruvec *lruvec, int type, bool can_swap) + + /* prevent cold/hot inversion if force_scan is true */ + for (zone = 0; zone < MAX_NR_ZONES; zone++) { +- struct list_head *head = &lrugen->lists[old_gen][type][zone]; ++ struct list_head *head = &lrugen->folios[old_gen][type][zone]; + + while (!list_empty(head)) { + struct folio *folio = lru_to_folio(head); +@@ -4269,7 +4269,7 @@ static bool inc_min_seq(struct lruvec *lruvec, int type, bool can_swap) + VM_WARN_ON_ONCE_FOLIO(folio_zonenum(folio) != zone, folio); + + new_gen = folio_inc_gen(lruvec, folio, false); +- list_move_tail(&folio->lru, &lrugen->lists[new_gen][type][zone]); ++ list_move_tail(&folio->lru, &lrugen->folios[new_gen][type][zone]); + + if (!--remaining) + return false; +@@ -4297,7 +4297,7 @@ static bool try_to_inc_min_seq(struct lruvec *lruvec, bool can_swap) + gen = lru_gen_from_seq(min_seq[type]); + + for (zone = 0; zone < MAX_NR_ZONES; zone++) { +- if (!list_empty(&lrugen->lists[gen][type][zone])) ++ if (!list_empty(&lrugen->folios[gen][type][zone])) + goto next; + } + +@@ -4762,7 +4762,7 @@ static bool sort_folio(struct lruvec *lruvec, struct folio *folio, int tier_idx) + + /* promoted */ + if (gen != lru_gen_from_seq(lrugen->min_seq[type])) { +- list_move(&folio->lru, &lrugen->lists[gen][type][zone]); ++ list_move(&folio->lru, &lrugen->folios[gen][type][zone]); + return true; + } + +@@ -4771,7 +4771,7 @@ static bool sort_folio(struct lruvec *lruvec, struct folio *folio, int tier_idx) + int hist = lru_hist_from_seq(lrugen->min_seq[type]); + + gen = folio_inc_gen(lruvec, folio, false); +- list_move_tail(&folio->lru, &lrugen->lists[gen][type][zone]); ++ list_move_tail(&folio->lru, &lrugen->folios[gen][type][zone]); + + WRITE_ONCE(lrugen->protected[hist][type][tier - 1], + lrugen->protected[hist][type][tier - 1] + delta); +@@ -4783,7 +4783,7 @@ static bool sort_folio(struct lruvec *lruvec, struct folio *folio, int tier_idx) + if (folio_test_locked(folio) || folio_test_writeback(folio) || + (type == LRU_GEN_FILE && folio_test_dirty(folio))) { + gen = folio_inc_gen(lruvec, folio, true); +- list_move(&folio->lru, &lrugen->lists[gen][type][zone]); ++ list_move(&folio->lru, &lrugen->folios[gen][type][zone]); + return true; + } + +@@ -4850,7 +4850,7 @@ static int scan_folios(struct lruvec *lruvec, struct scan_control *sc, + for (zone = sc->reclaim_idx; zone >= 0; zone--) { + LIST_HEAD(moved); + int skipped = 0; +- struct list_head *head = &lrugen->lists[gen][type][zone]; ++ struct list_head *head = &lrugen->folios[gen][type][zone]; + + while (!list_empty(head)) { + struct folio *folio = lru_to_folio(head); +@@ -5250,7 +5250,7 @@ static bool __maybe_unused state_is_valid(struct lruvec *lruvec) + int gen, type, zone; + + for_each_gen_type_zone(gen, type, zone) { +- if (!list_empty(&lrugen->lists[gen][type][zone])) ++ if (!list_empty(&lrugen->folios[gen][type][zone])) + return false; + } + } +@@ -5295,7 +5295,7 @@ static bool drain_evictable(struct lruvec *lruvec) + int remaining = MAX_LRU_BATCH; + + for_each_gen_type_zone(gen, type, zone) { +- struct list_head *head = &lruvec->lrugen.lists[gen][type][zone]; ++ struct list_head *head = &lruvec->lrugen.folios[gen][type][zone]; + + while (!list_empty(head)) { + bool success; +@@ -5832,7 +5832,7 @@ void lru_gen_init_lruvec(struct lruvec *lruvec) + lrugen->timestamps[i] = jiffies; + + for_each_gen_type_zone(gen, type, zone) +- INIT_LIST_HEAD(&lrugen->lists[gen][type][zone]); ++ INIT_LIST_HEAD(&lrugen->folios[gen][type][zone]); + + lruvec->mm_state.seq = MIN_NR_GENS; + init_waitqueue_head(&lruvec->mm_state.wait); +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-03-UPSTREAM-mm-multi-gen-LRU-remove-eviction-fairness-s.patch b/target/linux/generic/backport-6.1/020-v6.3-03-UPSTREAM-mm-multi-gen-LRU-remove-eviction-fairness-s.patch new file mode 100644 index 0000000000..6d764bb2b4 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-03-UPSTREAM-mm-multi-gen-LRU-remove-eviction-fairness-s.patch @@ -0,0 +1,197 @@ +From 14f9a7a15f3d1af351f30e0438fd747b7ac253b0 Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Wed, 21 Dec 2022 21:19:01 -0700 +Subject: [PATCH 03/19] UPSTREAM: mm: multi-gen LRU: remove eviction fairness + safeguard + +Recall that the eviction consumes the oldest generation: first it +bucket-sorts folios whose gen counters were updated by the aging and +reclaims the rest; then it increments lrugen->min_seq. + +The current eviction fairness safeguard for global reclaim has a +dilemma: when there are multiple eligible memcgs, should it continue +or stop upon meeting the reclaim goal? If it continues, it overshoots +and increases direct reclaim latency; if it stops, it loses fairness +between memcgs it has taken memory away from and those it has yet to. + +With memcg LRU, the eviction, while ensuring eventual fairness, will +stop upon meeting its goal. Therefore the current eviction fairness +safeguard for global reclaim will not be needed. + +Note that memcg LRU only applies to global reclaim. For memcg reclaim, +the eviction will continue, even if it is overshooting. This becomes +unconditional due to code simplification. + +Link: https://lkml.kernel.org/r/20221222041905.2431096-4-yuzhao@google.com +Signed-off-by: Yu Zhao +Cc: Johannes Weiner +Cc: Jonathan Corbet +Cc: Michael Larabel +Cc: Michal Hocko +Cc: Mike Rapoport +Cc: Roman Gushchin +Cc: Suren Baghdasaryan +Signed-off-by: Andrew Morton +Bug: 274865848 +(cherry picked from commit a579086c99ed70cc4bfc104348dbe3dd8f2787e6) +Change-Id: I08ac1b3c90e29cafd0566785aaa4bcdb5db7d22c +Signed-off-by: T.J. Mercier +--- + mm/vmscan.c | 81 +++++++++++++++-------------------------------------- + 1 file changed, 23 insertions(+), 58 deletions(-) + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index b02fed912f742..991961180b320 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -448,6 +448,11 @@ static bool cgroup_reclaim(struct scan_control *sc) + return sc->target_mem_cgroup; + } + ++static bool global_reclaim(struct scan_control *sc) ++{ ++ return !sc->target_mem_cgroup || mem_cgroup_is_root(sc->target_mem_cgroup); ++} ++ + /** + * writeback_throttling_sane - is the usual dirty throttling mechanism available? + * @sc: scan_control in question +@@ -498,6 +503,11 @@ static bool cgroup_reclaim(struct scan_control *sc) + return false; + } + ++static bool global_reclaim(struct scan_control *sc) ++{ ++ return true; ++} ++ + static bool writeback_throttling_sane(struct scan_control *sc) + { + return true; +@@ -4993,8 +5003,7 @@ static int isolate_folios(struct lruvec *lruvec, struct scan_control *sc, int sw + return scanned; + } + +-static int evict_folios(struct lruvec *lruvec, struct scan_control *sc, int swappiness, +- bool *need_swapping) ++static int evict_folios(struct lruvec *lruvec, struct scan_control *sc, int swappiness) + { + int type; + int scanned; +@@ -5083,9 +5092,6 @@ static int evict_folios(struct lruvec *lruvec, struct scan_control *sc, int swap + goto retry; + } + +- if (need_swapping && type == LRU_GEN_ANON) +- *need_swapping = true; +- + return scanned; + } + +@@ -5124,67 +5130,26 @@ static unsigned long get_nr_to_scan(struct lruvec *lruvec, struct scan_control * + return min_seq[!can_swap] + MIN_NR_GENS <= max_seq ? nr_to_scan : 0; + } + +-static bool should_abort_scan(struct lruvec *lruvec, unsigned long seq, +- struct scan_control *sc, bool need_swapping) ++static unsigned long get_nr_to_reclaim(struct scan_control *sc) + { +- int i; +- DEFINE_MAX_SEQ(lruvec); +- +- if (!current_is_kswapd()) { +- /* age each memcg at most once to ensure fairness */ +- if (max_seq - seq > 1) +- return true; +- +- /* over-swapping can increase allocation latency */ +- if (sc->nr_reclaimed >= sc->nr_to_reclaim && need_swapping) +- return true; +- +- /* give this thread a chance to exit and free its memory */ +- if (fatal_signal_pending(current)) { +- sc->nr_reclaimed += MIN_LRU_BATCH; +- return true; +- } +- +- if (cgroup_reclaim(sc)) +- return false; +- } else if (sc->nr_reclaimed - sc->last_reclaimed < sc->nr_to_reclaim) +- return false; +- +- /* keep scanning at low priorities to ensure fairness */ +- if (sc->priority > DEF_PRIORITY - 2) +- return false; +- +- /* +- * A minimum amount of work was done under global memory pressure. For +- * kswapd, it may be overshooting. For direct reclaim, the allocation +- * may succeed if all suitable zones are somewhat safe. In either case, +- * it's better to stop now, and restart later if necessary. +- */ +- for (i = 0; i <= sc->reclaim_idx; i++) { +- unsigned long wmark; +- struct zone *zone = lruvec_pgdat(lruvec)->node_zones + i; +- +- if (!managed_zone(zone)) +- continue; +- +- wmark = current_is_kswapd() ? high_wmark_pages(zone) : low_wmark_pages(zone); +- if (wmark > zone_page_state(zone, NR_FREE_PAGES)) +- return false; +- } ++ /* don't abort memcg reclaim to ensure fairness */ ++ if (!global_reclaim(sc)) ++ return -1; + +- sc->nr_reclaimed += MIN_LRU_BATCH; ++ /* discount the previous progress for kswapd */ ++ if (current_is_kswapd()) ++ return sc->nr_to_reclaim + sc->last_reclaimed; + +- return true; ++ return max(sc->nr_to_reclaim, compact_gap(sc->order)); + } + + static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) + { + struct blk_plug plug; + bool need_aging = false; +- bool need_swapping = false; + unsigned long scanned = 0; + unsigned long reclaimed = sc->nr_reclaimed; +- DEFINE_MAX_SEQ(lruvec); ++ unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); + + lru_add_drain(); + +@@ -5208,7 +5173,7 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc + if (!nr_to_scan) + goto done; + +- delta = evict_folios(lruvec, sc, swappiness, &need_swapping); ++ delta = evict_folios(lruvec, sc, swappiness); + if (!delta) + goto done; + +@@ -5216,7 +5181,7 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc + if (scanned >= nr_to_scan) + break; + +- if (should_abort_scan(lruvec, max_seq, sc, need_swapping)) ++ if (sc->nr_reclaimed >= nr_to_reclaim) + break; + + cond_resched(); +@@ -5666,7 +5631,7 @@ static int run_eviction(struct lruvec *lruvec, unsigned long seq, struct scan_co + if (sc->nr_reclaimed >= nr_to_reclaim) + return 0; + +- if (!evict_folios(lruvec, sc, swappiness, NULL)) ++ if (!evict_folios(lruvec, sc, swappiness)) + return 0; + + cond_resched(); +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-04-BACKPORT-mm-multi-gen-LRU-remove-aging-fairness-safe.patch b/target/linux/generic/backport-6.1/020-v6.3-04-BACKPORT-mm-multi-gen-LRU-remove-aging-fairness-safe.patch new file mode 100644 index 0000000000..c3f534a9e0 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-04-BACKPORT-mm-multi-gen-LRU-remove-aging-fairness-safe.patch @@ -0,0 +1,299 @@ +From f3c93d2e37a3c56593d7ccf4f4bcf1b58426fdd8 Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Wed, 21 Dec 2022 21:19:02 -0700 +Subject: [PATCH 04/19] BACKPORT: mm: multi-gen LRU: remove aging fairness + safeguard + +Recall that the aging produces the youngest generation: first it scans +for accessed folios and updates their gen counters; then it increments +lrugen->max_seq. + +The current aging fairness safeguard for kswapd uses two passes to +ensure the fairness to multiple eligible memcgs. On the first pass, +which is shared with the eviction, it checks whether all eligible +memcgs are low on cold folios. If so, it requires a second pass, on +which it ages all those memcgs at the same time. + +With memcg LRU, the aging, while ensuring eventual fairness, will run +when necessary. Therefore the current aging fairness safeguard for +kswapd will not be needed. + +Note that memcg LRU only applies to global reclaim. For memcg reclaim, +the aging can be unfair to different memcgs, i.e., their +lrugen->max_seq can be incremented at different paces. + +Link: https://lkml.kernel.org/r/20221222041905.2431096-5-yuzhao@google.com +Signed-off-by: Yu Zhao +Cc: Johannes Weiner +Cc: Jonathan Corbet +Cc: Michael Larabel +Cc: Michal Hocko +Cc: Mike Rapoport +Cc: Roman Gushchin +Cc: Suren Baghdasaryan +Signed-off-by: Andrew Morton +Bug: 274865848 +(cherry picked from commit 7348cc91821b0cb24dfb00e578047f68299a50ab) +[TJ: Resolved conflicts with older function signatures for +min_cgroup_below_min / min_cgroup_below_low] +Change-Id: I6e36ecfbaaefbc0a56d9a9d5d7cbe404ed7f57a5 +Signed-off-by: T.J. Mercier +--- + mm/vmscan.c | 126 ++++++++++++++++++++++++---------------------------- + 1 file changed, 59 insertions(+), 67 deletions(-) + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 991961180b320..5a2e83e673232 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -136,7 +136,6 @@ struct scan_control { + + #ifdef CONFIG_LRU_GEN + /* help kswapd make better choices among multiple memcgs */ +- unsigned int memcgs_need_aging:1; + unsigned long last_reclaimed; + #endif + +@@ -4455,7 +4454,7 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq, + return true; + } + +-static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, unsigned long *min_seq, ++static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, + struct scan_control *sc, bool can_swap, unsigned long *nr_to_scan) + { + int gen, type, zone; +@@ -4464,6 +4463,13 @@ static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, unsig + unsigned long total = 0; + struct lru_gen_folio *lrugen = &lruvec->lrugen; + struct mem_cgroup *memcg = lruvec_memcg(lruvec); ++ DEFINE_MIN_SEQ(lruvec); ++ ++ /* whether this lruvec is completely out of cold folios */ ++ if (min_seq[!can_swap] + MIN_NR_GENS > max_seq) { ++ *nr_to_scan = 0; ++ return true; ++ } + + for (type = !can_swap; type < ANON_AND_FILE; type++) { + unsigned long seq; +@@ -4492,8 +4498,6 @@ static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, unsig + * stalls when the number of generations reaches MIN_NR_GENS. Hence, the + * ideal number of generations is MIN_NR_GENS+1. + */ +- if (min_seq[!can_swap] + MIN_NR_GENS > max_seq) +- return true; + if (min_seq[!can_swap] + MIN_NR_GENS < max_seq) + return false; + +@@ -4512,40 +4516,54 @@ static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, unsig + return false; + } + +-static bool age_lruvec(struct lruvec *lruvec, struct scan_control *sc, unsigned long min_ttl) ++static bool lruvec_is_sizable(struct lruvec *lruvec, struct scan_control *sc) + { +- bool need_aging; +- unsigned long nr_to_scan; +- int swappiness = get_swappiness(lruvec, sc); ++ int gen, type, zone; ++ unsigned long total = 0; ++ bool can_swap = get_swappiness(lruvec, sc); ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; + struct mem_cgroup *memcg = lruvec_memcg(lruvec); + DEFINE_MAX_SEQ(lruvec); + DEFINE_MIN_SEQ(lruvec); + +- VM_WARN_ON_ONCE(sc->memcg_low_reclaim); ++ for (type = !can_swap; type < ANON_AND_FILE; type++) { ++ unsigned long seq; + +- mem_cgroup_calculate_protection(NULL, memcg); ++ for (seq = min_seq[type]; seq <= max_seq; seq++) { ++ gen = lru_gen_from_seq(seq); + +- if (mem_cgroup_below_min(memcg)) +- return false; ++ for (zone = 0; zone < MAX_NR_ZONES; zone++) ++ total += max(READ_ONCE(lrugen->nr_pages[gen][type][zone]), 0L); ++ } ++ } + +- need_aging = should_run_aging(lruvec, max_seq, min_seq, sc, swappiness, &nr_to_scan); ++ /* whether the size is big enough to be helpful */ ++ return mem_cgroup_online(memcg) ? (total >> sc->priority) : total; ++} + +- if (min_ttl) { +- int gen = lru_gen_from_seq(min_seq[LRU_GEN_FILE]); +- unsigned long birth = READ_ONCE(lruvec->lrugen.timestamps[gen]); ++static bool lruvec_is_reclaimable(struct lruvec *lruvec, struct scan_control *sc, ++ unsigned long min_ttl) ++{ ++ int gen; ++ unsigned long birth; ++ struct mem_cgroup *memcg = lruvec_memcg(lruvec); ++ DEFINE_MIN_SEQ(lruvec); + +- if (time_is_after_jiffies(birth + min_ttl)) +- return false; ++ VM_WARN_ON_ONCE(sc->memcg_low_reclaim); + +- /* the size is likely too small to be helpful */ +- if (!nr_to_scan && sc->priority != DEF_PRIORITY) +- return false; +- } ++ /* see the comment on lru_gen_folio */ ++ gen = lru_gen_from_seq(min_seq[LRU_GEN_FILE]); ++ birth = READ_ONCE(lruvec->lrugen.timestamps[gen]); + +- if (need_aging) +- try_to_inc_max_seq(lruvec, max_seq, sc, swappiness, false); ++ if (time_is_after_jiffies(birth + min_ttl)) ++ return false; + +- return true; ++ if (!lruvec_is_sizable(lruvec, sc)) ++ return false; ++ ++ mem_cgroup_calculate_protection(NULL, memcg); ++ ++ return !mem_cgroup_below_min(memcg); + } + + /* to protect the working set of the last N jiffies */ +@@ -4554,46 +4572,32 @@ static unsigned long lru_gen_min_ttl __read_mostly; + static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) + { + struct mem_cgroup *memcg; +- bool success = false; + unsigned long min_ttl = READ_ONCE(lru_gen_min_ttl); + + VM_WARN_ON_ONCE(!current_is_kswapd()); + + sc->last_reclaimed = sc->nr_reclaimed; + +- /* +- * To reduce the chance of going into the aging path, which can be +- * costly, optimistically skip it if the flag below was cleared in the +- * eviction path. This improves the overall performance when multiple +- * memcgs are available. +- */ +- if (!sc->memcgs_need_aging) { +- sc->memcgs_need_aging = true; ++ /* check the order to exclude compaction-induced reclaim */ ++ if (!min_ttl || sc->order || sc->priority == DEF_PRIORITY) + return; +- } +- +- set_mm_walk(pgdat); + + memcg = mem_cgroup_iter(NULL, NULL, NULL); + do { + struct lruvec *lruvec = mem_cgroup_lruvec(memcg, pgdat); + +- if (age_lruvec(lruvec, sc, min_ttl)) +- success = true; ++ if (lruvec_is_reclaimable(lruvec, sc, min_ttl)) { ++ mem_cgroup_iter_break(NULL, memcg); ++ return; ++ } + + cond_resched(); + } while ((memcg = mem_cgroup_iter(NULL, memcg, NULL))); + +- clear_mm_walk(); +- +- /* check the order to exclude compaction-induced reclaim */ +- if (success || !min_ttl || sc->order) +- return; +- + /* + * The main goal is to OOM kill if every generation from all memcgs is + * younger than min_ttl. However, another possibility is all memcgs are +- * either below min or empty. ++ * either too small or below min. + */ + if (mutex_trylock(&oom_lock)) { + struct oom_control oc = { +@@ -5101,33 +5105,27 @@ static int evict_folios(struct lruvec *lruvec, struct scan_control *sc, int swap + * reclaim. + */ + static unsigned long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, +- bool can_swap, bool *need_aging) ++ bool can_swap) + { + unsigned long nr_to_scan; + struct mem_cgroup *memcg = lruvec_memcg(lruvec); + DEFINE_MAX_SEQ(lruvec); +- DEFINE_MIN_SEQ(lruvec); + + if (mem_cgroup_below_min(memcg) || + (mem_cgroup_below_low(memcg) && !sc->memcg_low_reclaim)) + return 0; + +- *need_aging = should_run_aging(lruvec, max_seq, min_seq, sc, can_swap, &nr_to_scan); +- if (!*need_aging) ++ if (!should_run_aging(lruvec, max_seq, sc, can_swap, &nr_to_scan)) + return nr_to_scan; + + /* skip the aging path at the default priority */ + if (sc->priority == DEF_PRIORITY) +- goto done; ++ return nr_to_scan; + +- /* leave the work to lru_gen_age_node() */ +- if (current_is_kswapd()) +- return 0; ++ try_to_inc_max_seq(lruvec, max_seq, sc, can_swap, false); + +- if (try_to_inc_max_seq(lruvec, max_seq, sc, can_swap, false)) +- return nr_to_scan; +-done: +- return min_seq[!can_swap] + MIN_NR_GENS <= max_seq ? nr_to_scan : 0; ++ /* skip this lruvec as it's low on cold folios */ ++ return 0; + } + + static unsigned long get_nr_to_reclaim(struct scan_control *sc) +@@ -5146,9 +5144,7 @@ static unsigned long get_nr_to_reclaim(struct scan_control *sc) + static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) + { + struct blk_plug plug; +- bool need_aging = false; + unsigned long scanned = 0; +- unsigned long reclaimed = sc->nr_reclaimed; + unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); + + lru_add_drain(); +@@ -5169,13 +5165,13 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc + else + swappiness = 0; + +- nr_to_scan = get_nr_to_scan(lruvec, sc, swappiness, &need_aging); ++ nr_to_scan = get_nr_to_scan(lruvec, sc, swappiness); + if (!nr_to_scan) +- goto done; ++ break; + + delta = evict_folios(lruvec, sc, swappiness); + if (!delta) +- goto done; ++ break; + + scanned += delta; + if (scanned >= nr_to_scan) +@@ -5187,10 +5183,6 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc + cond_resched(); + } + +- /* see the comment in lru_gen_age_node() */ +- if (sc->nr_reclaimed - reclaimed >= MIN_LRU_BATCH && !need_aging) +- sc->memcgs_need_aging = false; +-done: + clear_mm_walk(); + + blk_finish_plug(&plug); +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-05-UPSTREAM-mm-multi-gen-LRU-shuffle-should_run_aging.patch b/target/linux/generic/backport-6.1/020-v6.3-05-UPSTREAM-mm-multi-gen-LRU-shuffle-should_run_aging.patch new file mode 100644 index 0000000000..d6bfe2a91c --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-05-UPSTREAM-mm-multi-gen-LRU-shuffle-should_run_aging.patch @@ -0,0 +1,171 @@ +From eca3858631e0cbad2ca6e40f788892749428e4cb Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Wed, 21 Dec 2022 21:19:03 -0700 +Subject: [PATCH 05/19] UPSTREAM: mm: multi-gen LRU: shuffle should_run_aging() + +Move should_run_aging() next to its only caller left. + +Link: https://lkml.kernel.org/r/20221222041905.2431096-6-yuzhao@google.com +Cc: Johannes Weiner +Cc: Jonathan Corbet +Cc: Michael Larabel +Cc: Michal Hocko +Cc: Mike Rapoport +Cc: Roman Gushchin +Cc: Suren Baghdasaryan +Signed-off-by: Andrew Morton +Bug: 274865848 +(cherry picked from commit 77d4459a4a1a472b7309e475f962dda87d950abd) +Signed-off-by: T.J. Mercier +Change-Id: I3b0383fe16b93a783b4d8c0b3a0b325160392576 +Signed-off-by: Yu Zhao +Signed-off-by: T.J. Mercier +--- + mm/vmscan.c | 124 ++++++++++++++++++++++++++-------------------------- + 1 file changed, 62 insertions(+), 62 deletions(-) + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 5a2e83e673232..0c47952714b26 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -4454,68 +4454,6 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq, + return true; + } + +-static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, +- struct scan_control *sc, bool can_swap, unsigned long *nr_to_scan) +-{ +- int gen, type, zone; +- unsigned long old = 0; +- unsigned long young = 0; +- unsigned long total = 0; +- struct lru_gen_folio *lrugen = &lruvec->lrugen; +- struct mem_cgroup *memcg = lruvec_memcg(lruvec); +- DEFINE_MIN_SEQ(lruvec); +- +- /* whether this lruvec is completely out of cold folios */ +- if (min_seq[!can_swap] + MIN_NR_GENS > max_seq) { +- *nr_to_scan = 0; +- return true; +- } +- +- for (type = !can_swap; type < ANON_AND_FILE; type++) { +- unsigned long seq; +- +- for (seq = min_seq[type]; seq <= max_seq; seq++) { +- unsigned long size = 0; +- +- gen = lru_gen_from_seq(seq); +- +- for (zone = 0; zone < MAX_NR_ZONES; zone++) +- size += max(READ_ONCE(lrugen->nr_pages[gen][type][zone]), 0L); +- +- total += size; +- if (seq == max_seq) +- young += size; +- else if (seq + MIN_NR_GENS == max_seq) +- old += size; +- } +- } +- +- /* try to scrape all its memory if this memcg was deleted */ +- *nr_to_scan = mem_cgroup_online(memcg) ? (total >> sc->priority) : total; +- +- /* +- * The aging tries to be lazy to reduce the overhead, while the eviction +- * stalls when the number of generations reaches MIN_NR_GENS. Hence, the +- * ideal number of generations is MIN_NR_GENS+1. +- */ +- if (min_seq[!can_swap] + MIN_NR_GENS < max_seq) +- return false; +- +- /* +- * It's also ideal to spread pages out evenly, i.e., 1/(MIN_NR_GENS+1) +- * of the total number of pages for each generation. A reasonable range +- * for this average portion is [1/MIN_NR_GENS, 1/(MIN_NR_GENS+2)]. The +- * aging cares about the upper bound of hot pages, while the eviction +- * cares about the lower bound of cold pages. +- */ +- if (young * MIN_NR_GENS > total) +- return true; +- if (old * (MIN_NR_GENS + 2) < total) +- return true; +- +- return false; +-} +- + static bool lruvec_is_sizable(struct lruvec *lruvec, struct scan_control *sc) + { + int gen, type, zone; +@@ -5099,6 +5037,68 @@ static int evict_folios(struct lruvec *lruvec, struct scan_control *sc, int swap + return scanned; + } + ++static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, ++ struct scan_control *sc, bool can_swap, unsigned long *nr_to_scan) ++{ ++ int gen, type, zone; ++ unsigned long old = 0; ++ unsigned long young = 0; ++ unsigned long total = 0; ++ struct lru_gen_folio *lrugen = &lruvec->lrugen; ++ struct mem_cgroup *memcg = lruvec_memcg(lruvec); ++ DEFINE_MIN_SEQ(lruvec); ++ ++ /* whether this lruvec is completely out of cold folios */ ++ if (min_seq[!can_swap] + MIN_NR_GENS > max_seq) { ++ *nr_to_scan = 0; ++ return true; ++ } ++ ++ for (type = !can_swap; type < ANON_AND_FILE; type++) { ++ unsigned long seq; ++ ++ for (seq = min_seq[type]; seq <= max_seq; seq++) { ++ unsigned long size = 0; ++ ++ gen = lru_gen_from_seq(seq); ++ ++ for (zone = 0; zone < MAX_NR_ZONES; zone++) ++ size += max(READ_ONCE(lrugen->nr_pages[gen][type][zone]), 0L); ++ ++ total += size; ++ if (seq == max_seq) ++ young += size; ++ else if (seq + MIN_NR_GENS == max_seq) ++ old += size; ++ } ++ } ++ ++ /* try to scrape all its memory if this memcg was deleted */ ++ *nr_to_scan = mem_cgroup_online(memcg) ? (total >> sc->priority) : total; ++ ++ /* ++ * The aging tries to be lazy to reduce the overhead, while the eviction ++ * stalls when the number of generations reaches MIN_NR_GENS. Hence, the ++ * ideal number of generations is MIN_NR_GENS+1. ++ */ ++ if (min_seq[!can_swap] + MIN_NR_GENS < max_seq) ++ return false; ++ ++ /* ++ * It's also ideal to spread pages out evenly, i.e., 1/(MIN_NR_GENS+1) ++ * of the total number of pages for each generation. A reasonable range ++ * for this average portion is [1/MIN_NR_GENS, 1/(MIN_NR_GENS+2)]. The ++ * aging cares about the upper bound of hot pages, while the eviction ++ * cares about the lower bound of cold pages. ++ */ ++ if (young * MIN_NR_GENS > total) ++ return true; ++ if (old * (MIN_NR_GENS + 2) < total) ++ return true; ++ ++ return false; ++} ++ + /* + * For future optimizations: + * 1. Defer try_to_inc_max_seq() to workqueues to reduce latency for memcg +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-06-BACKPORT-mm-multi-gen-LRU-per-node-lru_gen_folio-lis.patch b/target/linux/generic/backport-6.1/020-v6.3-06-BACKPORT-mm-multi-gen-LRU-per-node-lru_gen_folio-lis.patch new file mode 100644 index 0000000000..14f28820ec --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-06-BACKPORT-mm-multi-gen-LRU-per-node-lru_gen_folio-lis.patch @@ -0,0 +1,892 @@ +From 8ee8571e47aa75221e5fbd4c9c7802fc4244c346 Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Wed, 21 Dec 2022 21:19:04 -0700 +Subject: [PATCH 06/19] BACKPORT: mm: multi-gen LRU: per-node lru_gen_folio + lists + +For each node, memcgs are divided into two generations: the old and +the young. For each generation, memcgs are randomly sharded into +multiple bins to improve scalability. For each bin, an RCU hlist_nulls +is virtually divided into three segments: the head, the tail and the +default. + +An onlining memcg is added to the tail of a random bin in the old +generation. The eviction starts at the head of a random bin in the old +generation. The per-node memcg generation counter, whose reminder (mod +2) indexes the old generation, is incremented when all its bins become +empty. + +There are four operations: +1. MEMCG_LRU_HEAD, which moves an memcg to the head of a random bin in + its current generation (old or young) and updates its "seg" to + "head"; +2. MEMCG_LRU_TAIL, which moves an memcg to the tail of a random bin in + its current generation (old or young) and updates its "seg" to + "tail"; +3. MEMCG_LRU_OLD, which moves an memcg to the head of a random bin in + the old generation, updates its "gen" to "old" and resets its "seg" + to "default"; +4. MEMCG_LRU_YOUNG, which moves an memcg to the tail of a random bin + in the young generation, updates its "gen" to "young" and resets + its "seg" to "default". + +The events that trigger the above operations are: +1. Exceeding the soft limit, which triggers MEMCG_LRU_HEAD; +2. The first attempt to reclaim an memcg below low, which triggers + MEMCG_LRU_TAIL; +3. The first attempt to reclaim an memcg below reclaimable size + threshold, which triggers MEMCG_LRU_TAIL; +4. The second attempt to reclaim an memcg below reclaimable size + threshold, which triggers MEMCG_LRU_YOUNG; +5. Attempting to reclaim an memcg below min, which triggers + MEMCG_LRU_YOUNG; +6. Finishing the aging on the eviction path, which triggers + MEMCG_LRU_YOUNG; +7. Offlining an memcg, which triggers MEMCG_LRU_OLD. + +Note that memcg LRU only applies to global reclaim, and the +round-robin incrementing of their max_seq counters ensures the +eventual fairness to all eligible memcgs. For memcg reclaim, it still +relies on mem_cgroup_iter(). + +Link: https://lkml.kernel.org/r/20221222041905.2431096-7-yuzhao@google.com +Signed-off-by: Yu Zhao +Cc: Johannes Weiner +Cc: Jonathan Corbet +Cc: Michael Larabel +Cc: Michal Hocko +Cc: Mike Rapoport +Cc: Roman Gushchin +Cc: Suren Baghdasaryan +Signed-off-by: Andrew Morton +Bug: 274865848 +(cherry picked from commit e4dde56cd208674ce899b47589f263499e5b8cdc) +[TJ: Resolved conflicts with older function signatures for +min_cgroup_below_min / min_cgroup_below_low and includes] +Change-Id: Idc8a0f635e035d72dd911f807d1224cb47cbd655 +Signed-off-by: T.J. Mercier +--- + include/linux/memcontrol.h | 10 + + include/linux/mm_inline.h | 17 ++ + include/linux/mmzone.h | 117 +++++++++++- + mm/memcontrol.c | 16 ++ + mm/page_alloc.c | 1 + + mm/vmscan.c | 374 +++++++++++++++++++++++++++++++++---- + 6 files changed, 500 insertions(+), 35 deletions(-) + +diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h +index e039763029563..82d28b052a9e5 100644 +--- a/include/linux/memcontrol.h ++++ b/include/linux/memcontrol.h +@@ -790,6 +790,11 @@ static inline void obj_cgroup_put(struct obj_cgroup *objcg) + percpu_ref_put(&objcg->refcnt); + } + ++static inline bool mem_cgroup_tryget(struct mem_cgroup *memcg) ++{ ++ return !memcg || css_tryget(&memcg->css); ++} ++ + static inline void mem_cgroup_put(struct mem_cgroup *memcg) + { + if (memcg) +@@ -1290,6 +1295,11 @@ static inline void obj_cgroup_put(struct obj_cgroup *objcg) + { + } + ++static inline bool mem_cgroup_tryget(struct mem_cgroup *memcg) ++{ ++ return true; ++} ++ + static inline void mem_cgroup_put(struct mem_cgroup *memcg) + { + } +diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h +index da38e3d962e2f..c1fd3922dc5dd 100644 +--- a/include/linux/mm_inline.h ++++ b/include/linux/mm_inline.h +@@ -122,6 +122,18 @@ static inline bool lru_gen_in_fault(void) + return current->in_lru_fault; + } + ++#ifdef CONFIG_MEMCG ++static inline int lru_gen_memcg_seg(struct lruvec *lruvec) ++{ ++ return READ_ONCE(lruvec->lrugen.seg); ++} ++#else ++static inline int lru_gen_memcg_seg(struct lruvec *lruvec) ++{ ++ return 0; ++} ++#endif ++ + static inline int lru_gen_from_seq(unsigned long seq) + { + return seq % MAX_NR_GENS; +@@ -297,6 +309,11 @@ static inline bool lru_gen_in_fault(void) + return false; + } + ++static inline int lru_gen_memcg_seg(struct lruvec *lruvec) ++{ ++ return 0; ++} ++ + static inline bool lru_gen_add_folio(struct lruvec *lruvec, struct folio *folio, bool reclaiming) + { + return false; +diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h +index 02e4323744715..66e067a635682 100644 +--- a/include/linux/mmzone.h ++++ b/include/linux/mmzone.h +@@ -7,6 +7,7 @@ + + #include + #include ++#include + #include + #include + #include +@@ -367,6 +368,15 @@ struct page_vma_mapped_walk; + #define LRU_GEN_MASK ((BIT(LRU_GEN_WIDTH) - 1) << LRU_GEN_PGOFF) + #define LRU_REFS_MASK ((BIT(LRU_REFS_WIDTH) - 1) << LRU_REFS_PGOFF) + ++/* see the comment on MEMCG_NR_GENS */ ++enum { ++ MEMCG_LRU_NOP, ++ MEMCG_LRU_HEAD, ++ MEMCG_LRU_TAIL, ++ MEMCG_LRU_OLD, ++ MEMCG_LRU_YOUNG, ++}; ++ + #ifdef CONFIG_LRU_GEN + + enum { +@@ -426,6 +436,14 @@ struct lru_gen_folio { + atomic_long_t refaulted[NR_HIST_GENS][ANON_AND_FILE][MAX_NR_TIERS]; + /* whether the multi-gen LRU is enabled */ + bool enabled; ++#ifdef CONFIG_MEMCG ++ /* the memcg generation this lru_gen_folio belongs to */ ++ u8 gen; ++ /* the list segment this lru_gen_folio belongs to */ ++ u8 seg; ++ /* per-node lru_gen_folio list for global reclaim */ ++ struct hlist_nulls_node list; ++#endif + }; + + enum { +@@ -479,12 +497,87 @@ void lru_gen_init_lruvec(struct lruvec *lruvec); + void lru_gen_look_around(struct page_vma_mapped_walk *pvmw); + + #ifdef CONFIG_MEMCG ++ ++/* ++ * For each node, memcgs are divided into two generations: the old and the ++ * young. For each generation, memcgs are randomly sharded into multiple bins ++ * to improve scalability. For each bin, the hlist_nulls is virtually divided ++ * into three segments: the head, the tail and the default. ++ * ++ * An onlining memcg is added to the tail of a random bin in the old generation. ++ * The eviction starts at the head of a random bin in the old generation. The ++ * per-node memcg generation counter, whose reminder (mod MEMCG_NR_GENS) indexes ++ * the old generation, is incremented when all its bins become empty. ++ * ++ * There are four operations: ++ * 1. MEMCG_LRU_HEAD, which moves an memcg to the head of a random bin in its ++ * current generation (old or young) and updates its "seg" to "head"; ++ * 2. MEMCG_LRU_TAIL, which moves an memcg to the tail of a random bin in its ++ * current generation (old or young) and updates its "seg" to "tail"; ++ * 3. MEMCG_LRU_OLD, which moves an memcg to the head of a random bin in the old ++ * generation, updates its "gen" to "old" and resets its "seg" to "default"; ++ * 4. MEMCG_LRU_YOUNG, which moves an memcg to the tail of a random bin in the ++ * young generation, updates its "gen" to "young" and resets its "seg" to ++ * "default". ++ * ++ * The events that trigger the above operations are: ++ * 1. Exceeding the soft limit, which triggers MEMCG_LRU_HEAD; ++ * 2. The first attempt to reclaim an memcg below low, which triggers ++ * MEMCG_LRU_TAIL; ++ * 3. The first attempt to reclaim an memcg below reclaimable size threshold, ++ * which triggers MEMCG_LRU_TAIL; ++ * 4. The second attempt to reclaim an memcg below reclaimable size threshold, ++ * which triggers MEMCG_LRU_YOUNG; ++ * 5. Attempting to reclaim an memcg below min, which triggers MEMCG_LRU_YOUNG; ++ * 6. Finishing the aging on the eviction path, which triggers MEMCG_LRU_YOUNG; ++ * 7. Offlining an memcg, which triggers MEMCG_LRU_OLD. ++ * ++ * Note that memcg LRU only applies to global reclaim, and the round-robin ++ * incrementing of their max_seq counters ensures the eventual fairness to all ++ * eligible memcgs. For memcg reclaim, it still relies on mem_cgroup_iter(). ++ */ ++#define MEMCG_NR_GENS 2 ++#define MEMCG_NR_BINS 8 ++ ++struct lru_gen_memcg { ++ /* the per-node memcg generation counter */ ++ unsigned long seq; ++ /* each memcg has one lru_gen_folio per node */ ++ unsigned long nr_memcgs[MEMCG_NR_GENS]; ++ /* per-node lru_gen_folio list for global reclaim */ ++ struct hlist_nulls_head fifo[MEMCG_NR_GENS][MEMCG_NR_BINS]; ++ /* protects the above */ ++ spinlock_t lock; ++}; ++ ++void lru_gen_init_pgdat(struct pglist_data *pgdat); ++ + void lru_gen_init_memcg(struct mem_cgroup *memcg); + void lru_gen_exit_memcg(struct mem_cgroup *memcg); +-#endif ++void lru_gen_online_memcg(struct mem_cgroup *memcg); ++void lru_gen_offline_memcg(struct mem_cgroup *memcg); ++void lru_gen_release_memcg(struct mem_cgroup *memcg); ++void lru_gen_rotate_memcg(struct lruvec *lruvec, int op); ++ ++#else /* !CONFIG_MEMCG */ ++ ++#define MEMCG_NR_GENS 1 ++ ++struct lru_gen_memcg { ++}; ++ ++static inline void lru_gen_init_pgdat(struct pglist_data *pgdat) ++{ ++} ++ ++#endif /* CONFIG_MEMCG */ + + #else /* !CONFIG_LRU_GEN */ + ++static inline void lru_gen_init_pgdat(struct pglist_data *pgdat) ++{ ++} ++ + static inline void lru_gen_init_lruvec(struct lruvec *lruvec) + { + } +@@ -494,6 +587,7 @@ static inline void lru_gen_look_around(struct page_vma_mapped_walk *pvmw) + } + + #ifdef CONFIG_MEMCG ++ + static inline void lru_gen_init_memcg(struct mem_cgroup *memcg) + { + } +@@ -501,7 +595,24 @@ static inline void lru_gen_init_memcg(struct mem_cgroup *memcg) + static inline void lru_gen_exit_memcg(struct mem_cgroup *memcg) + { + } +-#endif ++ ++static inline void lru_gen_online_memcg(struct mem_cgroup *memcg) ++{ ++} ++ ++static inline void lru_gen_offline_memcg(struct mem_cgroup *memcg) ++{ ++} ++ ++static inline void lru_gen_release_memcg(struct mem_cgroup *memcg) ++{ ++} ++ ++static inline void lru_gen_rotate_memcg(struct lruvec *lruvec, int op) ++{ ++} ++ ++#endif /* CONFIG_MEMCG */ + + #endif /* CONFIG_LRU_GEN */ + +@@ -1219,6 +1330,8 @@ typedef struct pglist_data { + #ifdef CONFIG_LRU_GEN + /* kswap mm walk data */ + struct lru_gen_mm_walk mm_walk; ++ /* lru_gen_folio list */ ++ struct lru_gen_memcg memcg_lru; + #endif + + CACHELINE_PADDING(_pad2_); +diff --git a/mm/memcontrol.c b/mm/memcontrol.c +index 3e8f1ad0fe9db..7815d556e38cc 100644 +--- a/mm/memcontrol.c ++++ b/mm/memcontrol.c +@@ -477,6 +477,16 @@ static void mem_cgroup_update_tree(struct mem_cgroup *memcg, int nid) + struct mem_cgroup_per_node *mz; + struct mem_cgroup_tree_per_node *mctz; + ++ if (lru_gen_enabled()) { ++ struct lruvec *lruvec = &memcg->nodeinfo[nid]->lruvec; ++ ++ /* see the comment on MEMCG_NR_GENS */ ++ if (soft_limit_excess(memcg) && lru_gen_memcg_seg(lruvec) != MEMCG_LRU_HEAD) ++ lru_gen_rotate_memcg(lruvec, MEMCG_LRU_HEAD); ++ ++ return; ++ } ++ + mctz = soft_limit_tree.rb_tree_per_node[nid]; + if (!mctz) + return; +@@ -3522,6 +3532,9 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order, + struct mem_cgroup_tree_per_node *mctz; + unsigned long excess; + ++ if (lru_gen_enabled()) ++ return 0; ++ + if (order > 0) + return 0; + +@@ -5382,6 +5395,7 @@ static int mem_cgroup_css_online(struct cgroup_subsys_state *css) + if (unlikely(mem_cgroup_is_root(memcg))) + queue_delayed_work(system_unbound_wq, &stats_flush_dwork, + 2UL*HZ); ++ lru_gen_online_memcg(memcg); + return 0; + offline_kmem: + memcg_offline_kmem(memcg); +@@ -5413,6 +5427,7 @@ static void mem_cgroup_css_offline(struct cgroup_subsys_state *css) + memcg_offline_kmem(memcg); + reparent_shrinker_deferred(memcg); + wb_memcg_offline(memcg); ++ lru_gen_offline_memcg(memcg); + + drain_all_stock(memcg); + +@@ -5424,6 +5439,7 @@ static void mem_cgroup_css_released(struct cgroup_subsys_state *css) + struct mem_cgroup *memcg = mem_cgroup_from_css(css); + + invalidate_reclaim_iterators(memcg); ++ lru_gen_release_memcg(memcg); + } + + static void mem_cgroup_css_free(struct cgroup_subsys_state *css) +diff --git a/mm/page_alloc.c b/mm/page_alloc.c +index 69668817fed37..473057b81a9df 100644 +--- a/mm/page_alloc.c ++++ b/mm/page_alloc.c +@@ -7957,6 +7957,7 @@ static void __init free_area_init_node(int nid) + pgdat_set_deferred_range(pgdat); + + free_area_init_core(pgdat); ++ lru_gen_init_pgdat(pgdat); + } + + static void __init free_area_init_memoryless_node(int nid) +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 0c47952714b26..65eb28448f216 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -54,6 +54,8 @@ + #include + #include + #include ++#include ++#include + + #include + #include +@@ -134,11 +136,6 @@ struct scan_control { + /* Always discard instead of demoting to lower tier memory */ + unsigned int no_demotion:1; + +-#ifdef CONFIG_LRU_GEN +- /* help kswapd make better choices among multiple memcgs */ +- unsigned long last_reclaimed; +-#endif +- + /* Allocation order */ + s8 order; + +@@ -3160,6 +3157,9 @@ DEFINE_STATIC_KEY_ARRAY_FALSE(lru_gen_caps, NR_LRU_GEN_CAPS); + for ((type) = 0; (type) < ANON_AND_FILE; (type)++) \ + for ((zone) = 0; (zone) < MAX_NR_ZONES; (zone)++) + ++#define get_memcg_gen(seq) ((seq) % MEMCG_NR_GENS) ++#define get_memcg_bin(bin) ((bin) % MEMCG_NR_BINS) ++ + static struct lruvec *get_lruvec(struct mem_cgroup *memcg, int nid) + { + struct pglist_data *pgdat = NODE_DATA(nid); +@@ -4440,8 +4440,7 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq, + if (sc->priority <= DEF_PRIORITY - 2) + wait_event_killable(lruvec->mm_state.wait, + max_seq < READ_ONCE(lrugen->max_seq)); +- +- return max_seq < READ_ONCE(lrugen->max_seq); ++ return false; + } + + VM_WARN_ON_ONCE(max_seq != READ_ONCE(lrugen->max_seq)); +@@ -4514,8 +4513,6 @@ static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) + + VM_WARN_ON_ONCE(!current_is_kswapd()); + +- sc->last_reclaimed = sc->nr_reclaimed; +- + /* check the order to exclude compaction-induced reclaim */ + if (!min_ttl || sc->order || sc->priority == DEF_PRIORITY) + return; +@@ -5104,8 +5101,7 @@ static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, + * 1. Defer try_to_inc_max_seq() to workqueues to reduce latency for memcg + * reclaim. + */ +-static unsigned long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, +- bool can_swap) ++static long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, bool can_swap) + { + unsigned long nr_to_scan; + struct mem_cgroup *memcg = lruvec_memcg(lruvec); +@@ -5122,10 +5118,8 @@ static unsigned long get_nr_to_scan(struct lruvec *lruvec, struct scan_control * + if (sc->priority == DEF_PRIORITY) + return nr_to_scan; + +- try_to_inc_max_seq(lruvec, max_seq, sc, can_swap, false); +- + /* skip this lruvec as it's low on cold folios */ +- return 0; ++ return try_to_inc_max_seq(lruvec, max_seq, sc, can_swap, false) ? -1 : 0; + } + + static unsigned long get_nr_to_reclaim(struct scan_control *sc) +@@ -5134,29 +5128,18 @@ static unsigned long get_nr_to_reclaim(struct scan_control *sc) + if (!global_reclaim(sc)) + return -1; + +- /* discount the previous progress for kswapd */ +- if (current_is_kswapd()) +- return sc->nr_to_reclaim + sc->last_reclaimed; +- + return max(sc->nr_to_reclaim, compact_gap(sc->order)); + } + +-static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) ++static bool try_to_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) + { +- struct blk_plug plug; ++ long nr_to_scan; + unsigned long scanned = 0; + unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); + +- lru_add_drain(); +- +- blk_start_plug(&plug); +- +- set_mm_walk(lruvec_pgdat(lruvec)); +- + while (true) { + int delta; + int swappiness; +- unsigned long nr_to_scan; + + if (sc->may_swap) + swappiness = get_swappiness(lruvec, sc); +@@ -5166,7 +5149,7 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc + swappiness = 0; + + nr_to_scan = get_nr_to_scan(lruvec, sc, swappiness); +- if (!nr_to_scan) ++ if (nr_to_scan <= 0) + break; + + delta = evict_folios(lruvec, sc, swappiness); +@@ -5183,11 +5166,252 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc + cond_resched(); + } + ++ /* whether try_to_inc_max_seq() was successful */ ++ return nr_to_scan < 0; ++} ++ ++static int shrink_one(struct lruvec *lruvec, struct scan_control *sc) ++{ ++ bool success; ++ unsigned long scanned = sc->nr_scanned; ++ unsigned long reclaimed = sc->nr_reclaimed; ++ int seg = lru_gen_memcg_seg(lruvec); ++ struct mem_cgroup *memcg = lruvec_memcg(lruvec); ++ struct pglist_data *pgdat = lruvec_pgdat(lruvec); ++ ++ /* see the comment on MEMCG_NR_GENS */ ++ if (!lruvec_is_sizable(lruvec, sc)) ++ return seg != MEMCG_LRU_TAIL ? MEMCG_LRU_TAIL : MEMCG_LRU_YOUNG; ++ ++ mem_cgroup_calculate_protection(NULL, memcg); ++ ++ if (mem_cgroup_below_min(memcg)) ++ return MEMCG_LRU_YOUNG; ++ ++ if (mem_cgroup_below_low(memcg)) { ++ /* see the comment on MEMCG_NR_GENS */ ++ if (seg != MEMCG_LRU_TAIL) ++ return MEMCG_LRU_TAIL; ++ ++ memcg_memory_event(memcg, MEMCG_LOW); ++ } ++ ++ success = try_to_shrink_lruvec(lruvec, sc); ++ ++ shrink_slab(sc->gfp_mask, pgdat->node_id, memcg, sc->priority); ++ ++ if (!sc->proactive) ++ vmpressure(sc->gfp_mask, memcg, false, sc->nr_scanned - scanned, ++ sc->nr_reclaimed - reclaimed); ++ ++ sc->nr_reclaimed += current->reclaim_state->reclaimed_slab; ++ current->reclaim_state->reclaimed_slab = 0; ++ ++ return success ? MEMCG_LRU_YOUNG : 0; ++} ++ ++#ifdef CONFIG_MEMCG ++ ++static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc) ++{ ++ int gen; ++ int bin; ++ int first_bin; ++ struct lruvec *lruvec; ++ struct lru_gen_folio *lrugen; ++ const struct hlist_nulls_node *pos; ++ int op = 0; ++ struct mem_cgroup *memcg = NULL; ++ unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); ++ ++ bin = first_bin = get_random_u32_below(MEMCG_NR_BINS); ++restart: ++ gen = get_memcg_gen(READ_ONCE(pgdat->memcg_lru.seq)); ++ ++ rcu_read_lock(); ++ ++ hlist_nulls_for_each_entry_rcu(lrugen, pos, &pgdat->memcg_lru.fifo[gen][bin], list) { ++ if (op) ++ lru_gen_rotate_memcg(lruvec, op); ++ ++ mem_cgroup_put(memcg); ++ ++ lruvec = container_of(lrugen, struct lruvec, lrugen); ++ memcg = lruvec_memcg(lruvec); ++ ++ if (!mem_cgroup_tryget(memcg)) { ++ op = 0; ++ memcg = NULL; ++ continue; ++ } ++ ++ rcu_read_unlock(); ++ ++ op = shrink_one(lruvec, sc); ++ ++ if (sc->nr_reclaimed >= nr_to_reclaim) ++ goto success; ++ ++ rcu_read_lock(); ++ } ++ ++ rcu_read_unlock(); ++ ++ /* restart if raced with lru_gen_rotate_memcg() */ ++ if (gen != get_nulls_value(pos)) ++ goto restart; ++ ++ /* try the rest of the bins of the current generation */ ++ bin = get_memcg_bin(bin + 1); ++ if (bin != first_bin) ++ goto restart; ++success: ++ if (op) ++ lru_gen_rotate_memcg(lruvec, op); ++ ++ mem_cgroup_put(memcg); ++} ++ ++static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) ++{ ++ struct blk_plug plug; ++ ++ VM_WARN_ON_ONCE(global_reclaim(sc)); ++ ++ lru_add_drain(); ++ ++ blk_start_plug(&plug); ++ ++ set_mm_walk(lruvec_pgdat(lruvec)); ++ ++ if (try_to_shrink_lruvec(lruvec, sc)) ++ lru_gen_rotate_memcg(lruvec, MEMCG_LRU_YOUNG); ++ + clear_mm_walk(); + + blk_finish_plug(&plug); + } + ++#else /* !CONFIG_MEMCG */ ++ ++static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc) ++{ ++ BUILD_BUG(); ++} ++ ++static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) ++{ ++ BUILD_BUG(); ++} ++ ++#endif ++ ++static void set_initial_priority(struct pglist_data *pgdat, struct scan_control *sc) ++{ ++ int priority; ++ unsigned long reclaimable; ++ struct lruvec *lruvec = mem_cgroup_lruvec(NULL, pgdat); ++ ++ if (sc->priority != DEF_PRIORITY || sc->nr_to_reclaim < MIN_LRU_BATCH) ++ return; ++ /* ++ * Determine the initial priority based on ((total / MEMCG_NR_GENS) >> ++ * priority) * reclaimed_to_scanned_ratio = nr_to_reclaim, where the ++ * estimated reclaimed_to_scanned_ratio = inactive / total. ++ */ ++ reclaimable = node_page_state(pgdat, NR_INACTIVE_FILE); ++ if (get_swappiness(lruvec, sc)) ++ reclaimable += node_page_state(pgdat, NR_INACTIVE_ANON); ++ ++ reclaimable /= MEMCG_NR_GENS; ++ ++ /* round down reclaimable and round up sc->nr_to_reclaim */ ++ priority = fls_long(reclaimable) - 1 - fls_long(sc->nr_to_reclaim - 1); ++ ++ sc->priority = clamp(priority, 0, DEF_PRIORITY); ++} ++ ++static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control *sc) ++{ ++ struct blk_plug plug; ++ unsigned long reclaimed = sc->nr_reclaimed; ++ ++ VM_WARN_ON_ONCE(!global_reclaim(sc)); ++ ++ lru_add_drain(); ++ ++ blk_start_plug(&plug); ++ ++ set_mm_walk(pgdat); ++ ++ set_initial_priority(pgdat, sc); ++ ++ if (current_is_kswapd()) ++ sc->nr_reclaimed = 0; ++ ++ if (mem_cgroup_disabled()) ++ shrink_one(&pgdat->__lruvec, sc); ++ else ++ shrink_many(pgdat, sc); ++ ++ if (current_is_kswapd()) ++ sc->nr_reclaimed += reclaimed; ++ ++ clear_mm_walk(); ++ ++ blk_finish_plug(&plug); ++ ++ /* kswapd should never fail */ ++ pgdat->kswapd_failures = 0; ++} ++ ++#ifdef CONFIG_MEMCG ++void lru_gen_rotate_memcg(struct lruvec *lruvec, int op) ++{ ++ int seg; ++ int old, new; ++ int bin = get_random_u32_below(MEMCG_NR_BINS); ++ struct pglist_data *pgdat = lruvec_pgdat(lruvec); ++ ++ spin_lock(&pgdat->memcg_lru.lock); ++ ++ VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); ++ ++ seg = 0; ++ new = old = lruvec->lrugen.gen; ++ ++ /* see the comment on MEMCG_NR_GENS */ ++ if (op == MEMCG_LRU_HEAD) ++ seg = MEMCG_LRU_HEAD; ++ else if (op == MEMCG_LRU_TAIL) ++ seg = MEMCG_LRU_TAIL; ++ else if (op == MEMCG_LRU_OLD) ++ new = get_memcg_gen(pgdat->memcg_lru.seq); ++ else if (op == MEMCG_LRU_YOUNG) ++ new = get_memcg_gen(pgdat->memcg_lru.seq + 1); ++ else ++ VM_WARN_ON_ONCE(true); ++ ++ hlist_nulls_del_rcu(&lruvec->lrugen.list); ++ ++ if (op == MEMCG_LRU_HEAD || op == MEMCG_LRU_OLD) ++ hlist_nulls_add_head_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[new][bin]); ++ else ++ hlist_nulls_add_tail_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[new][bin]); ++ ++ pgdat->memcg_lru.nr_memcgs[old]--; ++ pgdat->memcg_lru.nr_memcgs[new]++; ++ ++ lruvec->lrugen.gen = new; ++ WRITE_ONCE(lruvec->lrugen.seg, seg); ++ ++ if (!pgdat->memcg_lru.nr_memcgs[old] && old == get_memcg_gen(pgdat->memcg_lru.seq)) ++ WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); ++ ++ spin_unlock(&pgdat->memcg_lru.lock); ++} ++#endif ++ + /****************************************************************************** + * state change + ******************************************************************************/ +@@ -5644,11 +5868,11 @@ static int run_cmd(char cmd, int memcg_id, int nid, unsigned long seq, + + if (!mem_cgroup_disabled()) { + rcu_read_lock(); ++ + memcg = mem_cgroup_from_id(memcg_id); +-#ifdef CONFIG_MEMCG +- if (memcg && !css_tryget(&memcg->css)) ++ if (!mem_cgroup_tryget(memcg)) + memcg = NULL; +-#endif ++ + rcu_read_unlock(); + + if (!memcg) +@@ -5796,6 +6020,19 @@ void lru_gen_init_lruvec(struct lruvec *lruvec) + } + + #ifdef CONFIG_MEMCG ++ ++void lru_gen_init_pgdat(struct pglist_data *pgdat) ++{ ++ int i, j; ++ ++ spin_lock_init(&pgdat->memcg_lru.lock); ++ ++ for (i = 0; i < MEMCG_NR_GENS; i++) { ++ for (j = 0; j < MEMCG_NR_BINS; j++) ++ INIT_HLIST_NULLS_HEAD(&pgdat->memcg_lru.fifo[i][j], i); ++ } ++} ++ + void lru_gen_init_memcg(struct mem_cgroup *memcg) + { + INIT_LIST_HEAD(&memcg->mm_list.fifo); +@@ -5819,7 +6056,69 @@ void lru_gen_exit_memcg(struct mem_cgroup *memcg) + } + } + } +-#endif ++ ++void lru_gen_online_memcg(struct mem_cgroup *memcg) ++{ ++ int gen; ++ int nid; ++ int bin = get_random_u32_below(MEMCG_NR_BINS); ++ ++ for_each_node(nid) { ++ struct pglist_data *pgdat = NODE_DATA(nid); ++ struct lruvec *lruvec = get_lruvec(memcg, nid); ++ ++ spin_lock(&pgdat->memcg_lru.lock); ++ ++ VM_WARN_ON_ONCE(!hlist_nulls_unhashed(&lruvec->lrugen.list)); ++ ++ gen = get_memcg_gen(pgdat->memcg_lru.seq); ++ ++ hlist_nulls_add_tail_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[gen][bin]); ++ pgdat->memcg_lru.nr_memcgs[gen]++; ++ ++ lruvec->lrugen.gen = gen; ++ ++ spin_unlock(&pgdat->memcg_lru.lock); ++ } ++} ++ ++void lru_gen_offline_memcg(struct mem_cgroup *memcg) ++{ ++ int nid; ++ ++ for_each_node(nid) { ++ struct lruvec *lruvec = get_lruvec(memcg, nid); ++ ++ lru_gen_rotate_memcg(lruvec, MEMCG_LRU_OLD); ++ } ++} ++ ++void lru_gen_release_memcg(struct mem_cgroup *memcg) ++{ ++ int gen; ++ int nid; ++ ++ for_each_node(nid) { ++ struct pglist_data *pgdat = NODE_DATA(nid); ++ struct lruvec *lruvec = get_lruvec(memcg, nid); ++ ++ spin_lock(&pgdat->memcg_lru.lock); ++ ++ VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); ++ ++ gen = lruvec->lrugen.gen; ++ ++ hlist_nulls_del_rcu(&lruvec->lrugen.list); ++ pgdat->memcg_lru.nr_memcgs[gen]--; ++ ++ if (!pgdat->memcg_lru.nr_memcgs[gen] && gen == get_memcg_gen(pgdat->memcg_lru.seq)) ++ WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); ++ ++ spin_unlock(&pgdat->memcg_lru.lock); ++ } ++} ++ ++#endif /* CONFIG_MEMCG */ + + static int __init init_lru_gen(void) + { +@@ -5846,6 +6145,10 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc + { + } + ++static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control *sc) ++{ ++} ++ + #endif /* CONFIG_LRU_GEN */ + + static void shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) +@@ -5859,7 +6162,7 @@ static void shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) + bool proportional_reclaim; + struct blk_plug plug; + +- if (lru_gen_enabled()) { ++ if (lru_gen_enabled() && !global_reclaim(sc)) { + lru_gen_shrink_lruvec(lruvec, sc); + return; + } +@@ -6102,6 +6405,11 @@ static void shrink_node(pg_data_t *pgdat, struct scan_control *sc) + struct lruvec *target_lruvec; + bool reclaimable = false; + ++ if (lru_gen_enabled() && global_reclaim(sc)) { ++ lru_gen_shrink_node(pgdat, sc); ++ return; ++ } ++ + target_lruvec = mem_cgroup_lruvec(sc->target_mem_cgroup, pgdat); + + again: +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-07-BACKPORT-mm-multi-gen-LRU-clarify-scan_control-flags.patch b/target/linux/generic/backport-6.1/020-v6.3-07-BACKPORT-mm-multi-gen-LRU-clarify-scan_control-flags.patch new file mode 100644 index 0000000000..9aaf247a09 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-07-BACKPORT-mm-multi-gen-LRU-clarify-scan_control-flags.patch @@ -0,0 +1,207 @@ +From 11b14ee8cbbbebd8204609076a9327a1171cd253 Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Wed, 21 Dec 2022 21:19:05 -0700 +Subject: [PATCH 07/19] BACKPORT: mm: multi-gen LRU: clarify scan_control flags + +Among the flags in scan_control: +1. sc->may_swap, which indicates swap constraint due to memsw.max, is + supported as usual. +2. sc->proactive, which indicates reclaim by memory.reclaim, may not + opportunistically skip the aging path, since it is considered less + latency sensitive. +3. !(sc->gfp_mask & __GFP_IO), which indicates IO constraint, lowers + swappiness to prioritize file LRU, since clean file folios are more + likely to exist. +4. sc->may_writepage and sc->may_unmap, which indicates opportunistic + reclaim, are rejected, since unmapped clean folios are already + prioritized. Scanning for more of them is likely futile and can + cause high reclaim latency when there is a large number of memcgs. + +The rest are handled by the existing code. + +Link: https://lkml.kernel.org/r/20221222041905.2431096-8-yuzhao@google.com +Signed-off-by: Yu Zhao +Cc: Johannes Weiner +Cc: Jonathan Corbet +Cc: Michael Larabel +Cc: Michal Hocko +Cc: Mike Rapoport +Cc: Roman Gushchin +Cc: Suren Baghdasaryan +Signed-off-by: Andrew Morton +Bug: 274865848 +(cherry picked from commit e9d4e1ee788097484606c32122f146d802a9c5fb) +[TJ: Resolved conflict with older function signature for min_cgroup_below_min, and over +cdded861182142ac4488a4d64c571107aeb77f53 ("ANDROID: MGLRU: Don't skip anon reclaim if swap low")] +Change-Id: Ic2e779eaf4e91a3921831b4e2fa10c740dc59d50 +Signed-off-by: T.J. Mercier +--- + mm/vmscan.c | 55 +++++++++++++++++++++++++++-------------------------- + 1 file changed, 28 insertions(+), 27 deletions(-) + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 65eb28448f216..0a0e1250ffc87 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -3185,6 +3185,9 @@ static int get_swappiness(struct lruvec *lruvec, struct scan_control *sc) + struct mem_cgroup *memcg = lruvec_memcg(lruvec); + struct pglist_data *pgdat = lruvec_pgdat(lruvec); + ++ if (!sc->may_swap) ++ return 0; ++ + if (!can_demote(pgdat->node_id, sc) && + mem_cgroup_get_nr_swap_pages(memcg) < MIN_LRU_BATCH) + return 0; +@@ -4223,7 +4226,7 @@ static void walk_mm(struct lruvec *lruvec, struct mm_struct *mm, struct lru_gen_ + } while (err == -EAGAIN); + } + +-static struct lru_gen_mm_walk *set_mm_walk(struct pglist_data *pgdat) ++static struct lru_gen_mm_walk *set_mm_walk(struct pglist_data *pgdat, bool force_alloc) + { + struct lru_gen_mm_walk *walk = current->reclaim_state->mm_walk; + +@@ -4231,7 +4234,7 @@ static struct lru_gen_mm_walk *set_mm_walk(struct pglist_data *pgdat) + VM_WARN_ON_ONCE(walk); + + walk = &pgdat->mm_walk; +- } else if (!pgdat && !walk) { ++ } else if (!walk && force_alloc) { + VM_WARN_ON_ONCE(current_is_kswapd()); + + walk = kzalloc(sizeof(*walk), __GFP_HIGH | __GFP_NOMEMALLOC | __GFP_NOWARN); +@@ -4417,7 +4420,7 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq, + goto done; + } + +- walk = set_mm_walk(NULL); ++ walk = set_mm_walk(NULL, true); + if (!walk) { + success = iterate_mm_list_nowalk(lruvec, max_seq); + goto done; +@@ -4486,8 +4489,6 @@ static bool lruvec_is_reclaimable(struct lruvec *lruvec, struct scan_control *sc + struct mem_cgroup *memcg = lruvec_memcg(lruvec); + DEFINE_MIN_SEQ(lruvec); + +- VM_WARN_ON_ONCE(sc->memcg_low_reclaim); +- + /* see the comment on lru_gen_folio */ + gen = lru_gen_from_seq(min_seq[LRU_GEN_FILE]); + birth = READ_ONCE(lruvec->lrugen.timestamps[gen]); +@@ -4743,12 +4744,8 @@ static bool isolate_folio(struct lruvec *lruvec, struct folio *folio, struct sca + { + bool success; + +- /* unmapping inhibited */ +- if (!sc->may_unmap && folio_mapped(folio)) +- return false; +- + /* swapping inhibited */ +- if (!(sc->may_writepage && (sc->gfp_mask & __GFP_IO)) && ++ if (!(sc->gfp_mask & __GFP_IO) && + (folio_test_dirty(folio) || + (folio_test_anon(folio) && !folio_test_swapcache(folio)))) + return false; +@@ -4845,9 +4842,8 @@ static int scan_folios(struct lruvec *lruvec, struct scan_control *sc, + __count_vm_events(PGSCAN_ANON + type, isolated); + + /* +- * There might not be eligible pages due to reclaim_idx, may_unmap and +- * may_writepage. Check the remaining to prevent livelock if it's not +- * making progress. ++ * There might not be eligible folios due to reclaim_idx. Check the ++ * remaining to prevent livelock if it's not making progress. + */ + return isolated || !remaining ? scanned : 0; + } +@@ -5107,8 +5103,7 @@ static long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, bool + struct mem_cgroup *memcg = lruvec_memcg(lruvec); + DEFINE_MAX_SEQ(lruvec); + +- if (mem_cgroup_below_min(memcg) || +- (mem_cgroup_below_low(memcg) && !sc->memcg_low_reclaim)) ++ if (mem_cgroup_below_min(memcg)) + return 0; + + if (!should_run_aging(lruvec, max_seq, sc, can_swap, &nr_to_scan)) +@@ -5136,17 +5131,14 @@ static bool try_to_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) + long nr_to_scan; + unsigned long scanned = 0; + unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); ++ int swappiness = get_swappiness(lruvec, sc); ++ ++ /* clean file folios are more likely to exist */ ++ if (swappiness && !(sc->gfp_mask & __GFP_IO)) ++ swappiness = 1; + + while (true) { + int delta; +- int swappiness; +- +- if (sc->may_swap) +- swappiness = get_swappiness(lruvec, sc); +- else if (!cgroup_reclaim(sc) && get_swappiness(lruvec, sc)) +- swappiness = 1; +- else +- swappiness = 0; + + nr_to_scan = get_nr_to_scan(lruvec, sc, swappiness); + if (nr_to_scan <= 0) +@@ -5277,12 +5269,13 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc + struct blk_plug plug; + + VM_WARN_ON_ONCE(global_reclaim(sc)); ++ VM_WARN_ON_ONCE(!sc->may_writepage || !sc->may_unmap); + + lru_add_drain(); + + blk_start_plug(&plug); + +- set_mm_walk(lruvec_pgdat(lruvec)); ++ set_mm_walk(NULL, sc->proactive); + + if (try_to_shrink_lruvec(lruvec, sc)) + lru_gen_rotate_memcg(lruvec, MEMCG_LRU_YOUNG); +@@ -5338,11 +5331,19 @@ static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control * + + VM_WARN_ON_ONCE(!global_reclaim(sc)); + ++ /* ++ * Unmapped clean folios are already prioritized. Scanning for more of ++ * them is likely futile and can cause high reclaim latency when there ++ * is a large number of memcgs. ++ */ ++ if (!sc->may_writepage || !sc->may_unmap) ++ goto done; ++ + lru_add_drain(); + + blk_start_plug(&plug); + +- set_mm_walk(pgdat); ++ set_mm_walk(pgdat, sc->proactive); + + set_initial_priority(pgdat, sc); + +@@ -5360,7 +5361,7 @@ static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control * + clear_mm_walk(); + + blk_finish_plug(&plug); +- ++done: + /* kswapd should never fail */ + pgdat->kswapd_failures = 0; + } +@@ -5932,7 +5933,7 @@ static ssize_t lru_gen_seq_write(struct file *file, const char __user *src, + set_task_reclaim_state(current, &sc.reclaim_state); + flags = memalloc_noreclaim_save(); + blk_start_plug(&plug); +- if (!set_mm_walk(NULL)) { ++ if (!set_mm_walk(NULL, true)) { + err = -ENOMEM; + goto done; + } +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-08-UPSTREAM-mm-multi-gen-LRU-simplify-arch_has_hw_pte_y.patch b/target/linux/generic/backport-6.1/020-v6.3-08-UPSTREAM-mm-multi-gen-LRU-simplify-arch_has_hw_pte_y.patch new file mode 100644 index 0000000000..adf85b616f --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-08-UPSTREAM-mm-multi-gen-LRU-simplify-arch_has_hw_pte_y.patch @@ -0,0 +1,43 @@ +From 25887d48dff860751a06caa4188bfaf6bfb6e4b2 Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Wed, 21 Dec 2022 21:19:06 -0700 +Subject: [PATCH 08/19] UPSTREAM: mm: multi-gen LRU: simplify + arch_has_hw_pte_young() check + +Scanning page tables when hardware does not set the accessed bit has +no real use cases. + +Link: https://lkml.kernel.org/r/20221222041905.2431096-9-yuzhao@google.com +Signed-off-by: Yu Zhao +Cc: Johannes Weiner +Cc: Jonathan Corbet +Cc: Michael Larabel +Cc: Michal Hocko +Cc: Mike Rapoport +Cc: Roman Gushchin +Cc: Suren Baghdasaryan +Signed-off-by: Andrew Morton +Bug: 274865848 +(cherry picked from commit f386e9314025ea99dae639ed2032560a92081430) +Change-Id: I84d97ab665b4e3bb862a9bc7d72f50dea7191a6b +Signed-off-by: T.J. Mercier +--- + mm/vmscan.c | 2 +- + 1 file changed, 1 insertion(+), 1 deletion(-) + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 0a0e1250ffc87..aa9746f2bc80b 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -4415,7 +4415,7 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq, + * handful of PTEs. Spreading the work out over a period of time usually + * is less efficient, but it avoids bursty page faults. + */ +- if (!force_scan && !(arch_has_hw_pte_young() && get_cap(LRU_GEN_MM_WALK))) { ++ if (!arch_has_hw_pte_young() || !get_cap(LRU_GEN_MM_WALK)) { + success = iterate_mm_list_nowalk(lruvec, max_seq); + goto done; + } +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-09-UPSTREAM-mm-multi-gen-LRU-avoid-futile-retries.patch b/target/linux/generic/backport-6.1/020-v6.3-09-UPSTREAM-mm-multi-gen-LRU-avoid-futile-retries.patch new file mode 100644 index 0000000000..2cf14d7816 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-09-UPSTREAM-mm-multi-gen-LRU-avoid-futile-retries.patch @@ -0,0 +1,97 @@ +From 620b0ee94455e48d124414cd06d8a53f69fb6453 Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Mon, 13 Feb 2023 00:53:22 -0700 +Subject: [PATCH 09/19] UPSTREAM: mm: multi-gen LRU: avoid futile retries + +Recall that the per-node memcg LRU has two generations and they alternate +when the last memcg (of a given node) is moved from one to the other. +Each generation is also sharded into multiple bins to improve scalability. +A reclaimer starts with a random bin (in the old generation) and, if it +fails, it will retry, i.e., to try the rest of the bins. + +If a reclaimer fails with the last memcg, it should move this memcg to the +young generation first, which causes the generations to alternate, and +then retry. Otherwise, the retries will be futile because all other bins +are empty. + +Link: https://lkml.kernel.org/r/20230213075322.1416966-1-yuzhao@google.com +Fixes: e4dde56cd208 ("mm: multi-gen LRU: per-node lru_gen_folio lists") +Signed-off-by: Yu Zhao +Reported-by: T.J. Mercier +Signed-off-by: Andrew Morton +Bug: 274865848 +(cherry picked from commit 9f550d78b40da21b4da515db4c37d8d7b12aa1a6) +Change-Id: Ie92535676b005ec9e7987632b742fdde8d54436f +Signed-off-by: T.J. Mercier +--- + mm/vmscan.c | 25 +++++++++++++++---------- + 1 file changed, 15 insertions(+), 10 deletions(-) + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index aa9746f2bc80b..49da02f841c81 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -5206,18 +5206,20 @@ static int shrink_one(struct lruvec *lruvec, struct scan_control *sc) + + static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc) + { ++ int op; + int gen; + int bin; + int first_bin; + struct lruvec *lruvec; + struct lru_gen_folio *lrugen; ++ struct mem_cgroup *memcg; + const struct hlist_nulls_node *pos; +- int op = 0; +- struct mem_cgroup *memcg = NULL; + unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); + + bin = first_bin = get_random_u32_below(MEMCG_NR_BINS); + restart: ++ op = 0; ++ memcg = NULL; + gen = get_memcg_gen(READ_ONCE(pgdat->memcg_lru.seq)); + + rcu_read_lock(); +@@ -5241,14 +5243,22 @@ static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc) + + op = shrink_one(lruvec, sc); + +- if (sc->nr_reclaimed >= nr_to_reclaim) +- goto success; +- + rcu_read_lock(); ++ ++ if (sc->nr_reclaimed >= nr_to_reclaim) ++ break; + } + + rcu_read_unlock(); + ++ if (op) ++ lru_gen_rotate_memcg(lruvec, op); ++ ++ mem_cgroup_put(memcg); ++ ++ if (sc->nr_reclaimed >= nr_to_reclaim) ++ return; ++ + /* restart if raced with lru_gen_rotate_memcg() */ + if (gen != get_nulls_value(pos)) + goto restart; +@@ -5257,11 +5267,6 @@ static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc) + bin = get_memcg_bin(bin + 1); + if (bin != first_bin) + goto restart; +-success: +- if (op) +- lru_gen_rotate_memcg(lruvec, op); +- +- mem_cgroup_put(memcg); + } + + static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-10-UPSTREAM-mm-add-vma_has_recency.patch b/target/linux/generic/backport-6.1/020-v6.3-10-UPSTREAM-mm-add-vma_has_recency.patch new file mode 100644 index 0000000000..0a0b439e25 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-10-UPSTREAM-mm-add-vma_has_recency.patch @@ -0,0 +1,202 @@ +From 70d216c71ff5c5b17dd1da6294f97b91fb6aba7a Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Fri, 30 Dec 2022 14:52:51 -0700 +Subject: [PATCH 10/19] UPSTREAM: mm: add vma_has_recency() + +Add vma_has_recency() to indicate whether a VMA may exhibit temporal +locality that the LRU algorithm relies on. + +This function returns false for VMAs marked by VM_SEQ_READ or +VM_RAND_READ. While the former flag indicates linear access, i.e., a +special case of spatial locality, both flags indicate a lack of temporal +locality, i.e., the reuse of an area within a relatively small duration. + +"Recency" is chosen over "locality" to avoid confusion between temporal +and spatial localities. + +Before this patch, the active/inactive LRU only ignored the accessed bit +from VMAs marked by VM_SEQ_READ. After this patch, the active/inactive +LRU and MGLRU share the same logic: they both ignore the accessed bit if +vma_has_recency() returns false. + +For the active/inactive LRU, the following fio test showed a [6, 8]% +increase in IOPS when randomly accessing mapped files under memory +pressure. + + kb=$(awk '/MemTotal/ { print $2 }' /proc/meminfo) + kb=$((kb - 8*1024*1024)) + + modprobe brd rd_nr=1 rd_size=$kb + dd if=/dev/zero of=/dev/ram0 bs=1M + + mkfs.ext4 /dev/ram0 + mount /dev/ram0 /mnt/ + swapoff -a + + fio --name=test --directory=/mnt/ --ioengine=mmap --numjobs=8 \ + --size=8G --rw=randrw --time_based --runtime=10m \ + --group_reporting + +The discussion that led to this patch is here [1]. Additional test +results are available in that thread. + +[1] https://lore.kernel.org/r/Y31s%2FK8T85jh05wH@google.com/ + +Link: https://lkml.kernel.org/r/20221230215252.2628425-1-yuzhao@google.com +Change-Id: I291dcb795197659e40e46539cd32b857677c34ad +Signed-off-by: Yu Zhao +Cc: Alexander Viro +Cc: Andrea Righi +Cc: Johannes Weiner +Cc: Michael Larabel +Signed-off-by: Andrew Morton +(cherry picked from commit 8788f6781486769d9598dcaedc3fe0eb12fc3e59) +Bug: 274865848 +Signed-off-by: T.J. Mercier +--- + include/linux/mm_inline.h | 8 ++++++++ + mm/memory.c | 7 +++---- + mm/rmap.c | 42 +++++++++++++++++---------------------- + mm/vmscan.c | 5 ++++- + 4 files changed, 33 insertions(+), 29 deletions(-) + +diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h +index c1fd3922dc5dd..7bb2e5f94734c 100644 +--- a/include/linux/mm_inline.h ++++ b/include/linux/mm_inline.h +@@ -595,4 +595,12 @@ pte_install_uffd_wp_if_needed(struct vm_area_struct *vma, unsigned long addr, + #endif + } + ++static inline bool vma_has_recency(struct vm_area_struct *vma) ++{ ++ if (vma->vm_flags & (VM_SEQ_READ | VM_RAND_READ)) ++ return false; ++ ++ return true; ++} ++ + #endif +diff --git a/mm/memory.c b/mm/memory.c +index 747b7ea30f890..c2f48f8003c2e 100644 +--- a/mm/memory.c ++++ b/mm/memory.c +@@ -1435,8 +1435,7 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb, + force_flush = 1; + set_page_dirty(page); + } +- if (pte_young(ptent) && +- likely(!(vma->vm_flags & VM_SEQ_READ))) ++ if (pte_young(ptent) && likely(vma_has_recency(vma))) + mark_page_accessed(page); + } + rss[mm_counter(page)]--; +@@ -5170,8 +5169,8 @@ static inline void mm_account_fault(struct pt_regs *regs, + #ifdef CONFIG_LRU_GEN + static void lru_gen_enter_fault(struct vm_area_struct *vma) + { +- /* the LRU algorithm doesn't apply to sequential or random reads */ +- current->in_lru_fault = !(vma->vm_flags & (VM_SEQ_READ | VM_RAND_READ)); ++ /* the LRU algorithm only applies to accesses with recency */ ++ current->in_lru_fault = vma_has_recency(vma); + } + + static void lru_gen_exit_fault(void) +diff --git a/mm/rmap.c b/mm/rmap.c +index 7da2d8d097d9b..825dac3caa1e5 100644 +--- a/mm/rmap.c ++++ b/mm/rmap.c +@@ -823,25 +823,14 @@ static bool folio_referenced_one(struct folio *folio, + } + + if (pvmw.pte) { +- if (lru_gen_enabled() && pte_young(*pvmw.pte) && +- !(vma->vm_flags & (VM_SEQ_READ | VM_RAND_READ))) { ++ if (lru_gen_enabled() && pte_young(*pvmw.pte)) { + lru_gen_look_around(&pvmw); + referenced++; + } + + if (ptep_clear_flush_young_notify(vma, address, +- pvmw.pte)) { +- /* +- * Don't treat a reference through +- * a sequentially read mapping as such. +- * If the folio has been used in another mapping, +- * we will catch it; if this other mapping is +- * already gone, the unmap path will have set +- * the referenced flag or activated the folio. +- */ +- if (likely(!(vma->vm_flags & VM_SEQ_READ))) +- referenced++; +- } ++ pvmw.pte)) ++ referenced++; + } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) { + if (pmdp_clear_flush_young_notify(vma, address, + pvmw.pmd)) +@@ -875,7 +864,20 @@ static bool invalid_folio_referenced_vma(struct vm_area_struct *vma, void *arg) + struct folio_referenced_arg *pra = arg; + struct mem_cgroup *memcg = pra->memcg; + +- if (!mm_match_cgroup(vma->vm_mm, memcg)) ++ /* ++ * Ignore references from this mapping if it has no recency. If the ++ * folio has been used in another mapping, we will catch it; if this ++ * other mapping is already gone, the unmap path will have set the ++ * referenced flag or activated the folio in zap_pte_range(). ++ */ ++ if (!vma_has_recency(vma)) ++ return true; ++ ++ /* ++ * If we are reclaiming on behalf of a cgroup, skip counting on behalf ++ * of references from different cgroups. ++ */ ++ if (memcg && !mm_match_cgroup(vma->vm_mm, memcg)) + return true; + + return false; +@@ -906,6 +908,7 @@ int folio_referenced(struct folio *folio, int is_locked, + .arg = (void *)&pra, + .anon_lock = folio_lock_anon_vma_read, + .try_lock = true, ++ .invalid_vma = invalid_folio_referenced_vma, + }; + + *vm_flags = 0; +@@ -921,15 +924,6 @@ int folio_referenced(struct folio *folio, int is_locked, + return 1; + } + +- /* +- * If we are reclaiming on behalf of a cgroup, skip +- * counting on behalf of references from different +- * cgroups +- */ +- if (memcg) { +- rwc.invalid_vma = invalid_folio_referenced_vma; +- } +- + rmap_walk(folio, &rwc); + *vm_flags = pra.vm_flags; + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 49da02f841c81..596fed6ae0439 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -3778,7 +3778,10 @@ static int should_skip_vma(unsigned long start, unsigned long end, struct mm_wal + if (is_vm_hugetlb_page(vma)) + return true; + +- if (vma->vm_flags & (VM_LOCKED | VM_SPECIAL | VM_SEQ_READ | VM_RAND_READ)) ++ if (!vma_has_recency(vma)) ++ return true; ++ ++ if (vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) + return true; + + if (vma == get_gate_vma(vma->vm_mm)) +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-11-UPSTREAM-mm-support-POSIX_FADV_NOREUSE.patch b/target/linux/generic/backport-6.1/020-v6.3-11-UPSTREAM-mm-support-POSIX_FADV_NOREUSE.patch new file mode 100644 index 0000000000..4c6fcecdac --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-11-UPSTREAM-mm-support-POSIX_FADV_NOREUSE.patch @@ -0,0 +1,138 @@ +From 9ca4e437a24dfc4ec6c362f319eb9850b9eca497 Mon Sep 17 00:00:00 2001 +From: Yu Zhao +Date: Fri, 30 Dec 2022 14:52:52 -0700 +Subject: [PATCH 11/19] UPSTREAM: mm: support POSIX_FADV_NOREUSE + +This patch adds POSIX_FADV_NOREUSE to vma_has_recency() so that the LRU +algorithm can ignore access to mapped files marked by this flag. + +The advantages of POSIX_FADV_NOREUSE are: +1. Unlike MADV_SEQUENTIAL and MADV_RANDOM, it does not alter the + default readahead behavior. +2. Unlike MADV_SEQUENTIAL and MADV_RANDOM, it does not split VMAs and + therefore does not take mmap_lock. +3. Unlike MADV_COLD, setting it has a negligible cost, regardless of + how many pages it affects. + +Its limitations are: +1. Like POSIX_FADV_RANDOM and POSIX_FADV_SEQUENTIAL, it currently does + not support range. IOW, its scope is the entire file. +2. It currently does not ignore access through file descriptors. + Specifically, for the active/inactive LRU, given a file page shared + by two users and one of them having set POSIX_FADV_NOREUSE on the + file, this page will be activated upon the second user accessing + it. This corner case can be covered by checking POSIX_FADV_NOREUSE + before calling folio_mark_accessed() on the read path. But it is + considered not worth the effort. + +There have been a few attempts to support POSIX_FADV_NOREUSE, e.g., [1]. +This time the goal is to fill a niche: a few desktop applications, e.g., +large file transferring and video encoding/decoding, want fast file +streaming with mmap() rather than direct IO. Among those applications, an +SVT-AV1 regression was reported when running with MGLRU [2]. The +following test can reproduce that regression. + + kb=$(awk '/MemTotal/ { print $2 }' /proc/meminfo) + kb=$((kb - 8*1024*1024)) + + modprobe brd rd_nr=1 rd_size=$kb + dd if=/dev/zero of=/dev/ram0 bs=1M + + mkfs.ext4 /dev/ram0 + mount /dev/ram0 /mnt/ + swapoff -a + + fallocate -l 8G /mnt/swapfile + mkswap /mnt/swapfile + swapon /mnt/swapfile + + wget http://ultravideo.cs.tut.fi/video/Bosphorus_3840x2160_120fps_420_8bit_YUV_Y4M.7z + 7z e -o/mnt/ Bosphorus_3840x2160_120fps_420_8bit_YUV_Y4M.7z + SvtAv1EncApp --preset 12 -w 3840 -h 2160 \ + -i /mnt/Bosphorus_3840x2160.y4m + +For MGLRU, the following change showed a [9-11]% increase in FPS, +which makes it on par with the active/inactive LRU. + + patch Source/App/EncApp/EbAppMain.c < #include + 35d35 + < #include /* _O_BINARY */ + 117a118 + > posix_fadvise(config->mmap.fd, 0, 0, POSIX_FADV_NOREUSE); + EOF + +[1] https://lore.kernel.org/r/1308923350-7932-1-git-send-email-andrea@betterlinux.com/ +[2] https://openbenchmarking.org/result/2209259-PTS-MGLRU8GB57 + +Link: https://lkml.kernel.org/r/20221230215252.2628425-2-yuzhao@google.com +Change-Id: I0b7f5f971d78014ea1ba44cee6a8ec902a4330d0 +Signed-off-by: Yu Zhao +Cc: Alexander Viro +Cc: Andrea Righi +Cc: Johannes Weiner +Cc: Michael Larabel +Signed-off-by: Andrew Morton +(cherry picked from commit 17e810229cb3068b692fa078bd9b3a6527e0866a) +Bug: 274865848 +Signed-off-by: T.J. Mercier +--- + include/linux/fs.h | 2 ++ + include/linux/mm_inline.h | 3 +++ + mm/fadvise.c | 5 ++++- + 3 files changed, 9 insertions(+), 1 deletion(-) + +diff --git a/include/linux/fs.h b/include/linux/fs.h +index f14ecbeab2a9d..97f9c41c1a43a 100644 +--- a/include/linux/fs.h ++++ b/include/linux/fs.h +@@ -166,6 +166,8 @@ typedef int (dio_iodone_t)(struct kiocb *iocb, loff_t offset, + /* File supports DIRECT IO */ + #define FMODE_CAN_ODIRECT ((__force fmode_t)0x400000) + ++#define FMODE_NOREUSE ((__force fmode_t)0x800000) ++ + /* File was opened by fanotify and shouldn't generate fanotify events */ + #define FMODE_NONOTIFY ((__force fmode_t)0x4000000) + +diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h +index 7bb2e5f94734c..9a8e2049333c0 100644 +--- a/include/linux/mm_inline.h ++++ b/include/linux/mm_inline.h +@@ -600,6 +600,9 @@ static inline bool vma_has_recency(struct vm_area_struct *vma) + if (vma->vm_flags & (VM_SEQ_READ | VM_RAND_READ)) + return false; + ++ if (vma->vm_file && (vma->vm_file->f_mode & FMODE_NOREUSE)) ++ return false; ++ + return true; + } + +diff --git a/mm/fadvise.c b/mm/fadvise.c +index c76ee665355a4..2ba24d865bf5f 100644 +--- a/mm/fadvise.c ++++ b/mm/fadvise.c +@@ -80,7 +80,7 @@ int generic_fadvise(struct file *file, loff_t offset, loff_t len, int advice) + case POSIX_FADV_NORMAL: + file->f_ra.ra_pages = bdi->ra_pages; + spin_lock(&file->f_lock); +- file->f_mode &= ~FMODE_RANDOM; ++ file->f_mode &= ~(FMODE_RANDOM | FMODE_NOREUSE); + spin_unlock(&file->f_lock); + break; + case POSIX_FADV_RANDOM: +@@ -107,6 +107,9 @@ int generic_fadvise(struct file *file, loff_t offset, loff_t len, int advice) + force_page_cache_readahead(mapping, file, start_index, nrpages); + break; + case POSIX_FADV_NOREUSE: ++ spin_lock(&file->f_lock); ++ file->f_mode |= FMODE_NOREUSE; ++ spin_unlock(&file->f_lock); + break; + case POSIX_FADV_DONTNEED: + __filemap_fdatawrite_range(mapping, offset, endbyte, +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-12-UPSTREAM-mm-multi-gen-LRU-section-for-working-set-pr.patch b/target/linux/generic/backport-6.1/020-v6.3-12-UPSTREAM-mm-multi-gen-LRU-section-for-working-set-pr.patch new file mode 100644 index 0000000000..08804e0023 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-12-UPSTREAM-mm-multi-gen-LRU-section-for-working-set-pr.patch @@ -0,0 +1,74 @@ +From 1b5e4c317d80f4826eceb3781702d18d06b14394 Mon Sep 17 00:00:00 2001 +From: "T.J. Alumbaugh" +Date: Wed, 18 Jan 2023 00:18:21 +0000 +Subject: [PATCH 12/19] UPSTREAM: mm: multi-gen LRU: section for working set + protection + +Patch series "mm: multi-gen LRU: improve". + +This patch series improves a few MGLRU functions, collects related +functions, and adds additional documentation. + +This patch (of 7): + +Add a section for working set protection in the code and the design doc. +The admin doc already contains its usage. + +Link: https://lkml.kernel.org/r/20230118001827.1040870-1-talumbau@google.com +Link: https://lkml.kernel.org/r/20230118001827.1040870-2-talumbau@google.com +Change-Id: I65599075fd42951db7739a2ab7cee78516e157b3 +Signed-off-by: T.J. Alumbaugh +Cc: Yu Zhao +Signed-off-by: Andrew Morton +(cherry picked from commit 7b8144e63d84716f16a1b929e0c7e03ae5c4d5c1) +Bug: 274865848 +Signed-off-by: T.J. Mercier +--- + Documentation/mm/multigen_lru.rst | 15 +++++++++++++++ + mm/vmscan.c | 4 ++++ + 2 files changed, 19 insertions(+) + +diff --git a/Documentation/mm/multigen_lru.rst b/Documentation/mm/multigen_lru.rst +index d8f721f98868a..6e1483e70fdca 100644 +--- a/Documentation/mm/multigen_lru.rst ++++ b/Documentation/mm/multigen_lru.rst +@@ -141,6 +141,21 @@ loop has detected outlying refaults from the tier this page is in. To + this end, the feedback loop uses the first tier as the baseline, for + the reason stated earlier. + ++Working set protection ++---------------------- ++Each generation is timestamped at birth. If ``lru_gen_min_ttl`` is ++set, an ``lruvec`` is protected from the eviction when its oldest ++generation was born within ``lru_gen_min_ttl`` milliseconds. In other ++words, it prevents the working set of ``lru_gen_min_ttl`` milliseconds ++from getting evicted. The OOM killer is triggered if this working set ++cannot be kept in memory. ++ ++This time-based approach has the following advantages: ++ ++1. It is easier to configure because it is agnostic to applications ++ and memory sizes. ++2. It is more reliable because it is directly wired to the OOM killer. ++ + Summary + ------- + The multi-gen LRU can be disassembled into the following parts: +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 596fed6ae0439..ab0b8d3b9d88f 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -4459,6 +4459,10 @@ static bool try_to_inc_max_seq(struct lruvec *lruvec, unsigned long max_seq, + return true; + } + ++/****************************************************************************** ++ * working set protection ++ ******************************************************************************/ ++ + static bool lruvec_is_sizable(struct lruvec *lruvec, struct scan_control *sc) + { + int gen, type, zone; +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-13-UPSTREAM-mm-multi-gen-LRU-section-for-rmap-PT-walk-f.patch b/target/linux/generic/backport-6.1/020-v6.3-13-UPSTREAM-mm-multi-gen-LRU-section-for-rmap-PT-walk-f.patch new file mode 100644 index 0000000000..f80dedb405 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-13-UPSTREAM-mm-multi-gen-LRU-section-for-rmap-PT-walk-f.patch @@ -0,0 +1,64 @@ +From 5ddf9d53d375e42af49b744bd7c2f8247c6bce15 Mon Sep 17 00:00:00 2001 +From: "T.J. Alumbaugh" +Date: Wed, 18 Jan 2023 00:18:22 +0000 +Subject: [PATCH 13/19] UPSTREAM: mm: multi-gen LRU: section for rmap/PT walk + feedback + +Add a section for lru_gen_look_around() in the code and the design doc. + +Link: https://lkml.kernel.org/r/20230118001827.1040870-3-talumbau@google.com +Change-Id: I5097af63f61b3b69ec2abee6cdbdc33c296df213 +Signed-off-by: T.J. Alumbaugh +Cc: Yu Zhao +Signed-off-by: Andrew Morton +(cherry picked from commit db19a43d9b3a8876552f00f656008206ef9a5efa) +Bug: 274865848 +Signed-off-by: T.J. Mercier +--- + Documentation/mm/multigen_lru.rst | 14 ++++++++++++++ + mm/vmscan.c | 4 ++++ + 2 files changed, 18 insertions(+) + +diff --git a/Documentation/mm/multigen_lru.rst b/Documentation/mm/multigen_lru.rst +index 6e1483e70fdca..bd988a142bc2f 100644 +--- a/Documentation/mm/multigen_lru.rst ++++ b/Documentation/mm/multigen_lru.rst +@@ -156,6 +156,20 @@ This time-based approach has the following advantages: + and memory sizes. + 2. It is more reliable because it is directly wired to the OOM killer. + ++Rmap/PT walk feedback ++--------------------- ++Searching the rmap for PTEs mapping each page on an LRU list (to test ++and clear the accessed bit) can be expensive because pages from ++different VMAs (PA space) are not cache friendly to the rmap (VA ++space). For workloads mostly using mapped pages, searching the rmap ++can incur the highest CPU cost in the reclaim path. ++ ++``lru_gen_look_around()`` exploits spatial locality to reduce the ++trips into the rmap. It scans the adjacent PTEs of a young PTE and ++promotes hot pages. If the scan was done cacheline efficiently, it ++adds the PMD entry pointing to the PTE table to the Bloom filter. This ++forms a feedback loop between the eviction and the aging. ++ + Summary + ------- + The multi-gen LRU can be disassembled into the following parts: +diff --git a/mm/vmscan.c b/mm/vmscan.c +index ab0b8d3b9d88f..8fa82630240d6 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -4553,6 +4553,10 @@ static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) + } + } + ++/****************************************************************************** ++ * rmap/PT walk feedback ++ ******************************************************************************/ ++ + /* + * This function exploits spatial locality when shrink_folio_list() walks the + * rmap. It scans the adjacent PTEs of a young PTE and promotes hot pages. If +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-14-UPSTREAM-mm-multi-gen-LRU-section-for-Bloom-filters.patch b/target/linux/generic/backport-6.1/020-v6.3-14-UPSTREAM-mm-multi-gen-LRU-section-for-Bloom-filters.patch new file mode 100644 index 0000000000..f98588c4d8 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-14-UPSTREAM-mm-multi-gen-LRU-section-for-Bloom-filters.patch @@ -0,0 +1,250 @@ +From 397624e12244ec038f51cb1f178ccb7a2ec562e5 Mon Sep 17 00:00:00 2001 +From: "T.J. Alumbaugh" +Date: Wed, 18 Jan 2023 00:18:23 +0000 +Subject: [PATCH 14/19] UPSTREAM: mm: multi-gen LRU: section for Bloom filters + +Move Bloom filters code into a dedicated section. Improve the design doc +to explain Bloom filter usage and connection between aging and eviction in +their use. + +Link: https://lkml.kernel.org/r/20230118001827.1040870-4-talumbau@google.com +Change-Id: I73e866f687c1ed9f5c8538086aa39408b79897db +Signed-off-by: T.J. Alumbaugh +Cc: Yu Zhao +Signed-off-by: Andrew Morton +(cherry picked from commit ccbbbb85945d8f0255aa9dbc1b617017e2294f2c) +Bug: 274865848 +Signed-off-by: T.J. Mercier +--- + Documentation/mm/multigen_lru.rst | 16 +++ + mm/vmscan.c | 180 +++++++++++++++--------------- + 2 files changed, 108 insertions(+), 88 deletions(-) + +diff --git a/Documentation/mm/multigen_lru.rst b/Documentation/mm/multigen_lru.rst +index bd988a142bc2f..770b5d539856c 100644 +--- a/Documentation/mm/multigen_lru.rst ++++ b/Documentation/mm/multigen_lru.rst +@@ -170,6 +170,22 @@ promotes hot pages. If the scan was done cacheline efficiently, it + adds the PMD entry pointing to the PTE table to the Bloom filter. This + forms a feedback loop between the eviction and the aging. + ++Bloom Filters ++------------- ++Bloom filters are a space and memory efficient data structure for set ++membership test, i.e., test if an element is not in the set or may be ++in the set. ++ ++In the eviction path, specifically, in ``lru_gen_look_around()``, if a ++PMD has a sufficient number of hot pages, its address is placed in the ++filter. In the aging path, set membership means that the PTE range ++will be scanned for young pages. ++ ++Note that Bloom filters are probabilistic on set membership. If a test ++is false positive, the cost is an additional scan of a range of PTEs, ++which may yield hot pages anyway. Parameters of the filter itself can ++control the false positive rate in the limit. ++ + Summary + ------- + The multi-gen LRU can be disassembled into the following parts: +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 8fa82630240d6..74b4f9d660b56 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -3208,6 +3208,98 @@ static bool __maybe_unused seq_is_valid(struct lruvec *lruvec) + get_nr_gens(lruvec, LRU_GEN_ANON) <= MAX_NR_GENS; + } + ++/****************************************************************************** ++ * Bloom filters ++ ******************************************************************************/ ++ ++/* ++ * Bloom filters with m=1<<15, k=2 and the false positive rates of ~1/5 when ++ * n=10,000 and ~1/2 when n=20,000, where, conventionally, m is the number of ++ * bits in a bitmap, k is the number of hash functions and n is the number of ++ * inserted items. ++ * ++ * Page table walkers use one of the two filters to reduce their search space. ++ * To get rid of non-leaf entries that no longer have enough leaf entries, the ++ * aging uses the double-buffering technique to flip to the other filter each ++ * time it produces a new generation. For non-leaf entries that have enough ++ * leaf entries, the aging carries them over to the next generation in ++ * walk_pmd_range(); the eviction also report them when walking the rmap ++ * in lru_gen_look_around(). ++ * ++ * For future optimizations: ++ * 1. It's not necessary to keep both filters all the time. The spare one can be ++ * freed after the RCU grace period and reallocated if needed again. ++ * 2. And when reallocating, it's worth scaling its size according to the number ++ * of inserted entries in the other filter, to reduce the memory overhead on ++ * small systems and false positives on large systems. ++ * 3. Jenkins' hash function is an alternative to Knuth's. ++ */ ++#define BLOOM_FILTER_SHIFT 15 ++ ++static inline int filter_gen_from_seq(unsigned long seq) ++{ ++ return seq % NR_BLOOM_FILTERS; ++} ++ ++static void get_item_key(void *item, int *key) ++{ ++ u32 hash = hash_ptr(item, BLOOM_FILTER_SHIFT * 2); ++ ++ BUILD_BUG_ON(BLOOM_FILTER_SHIFT * 2 > BITS_PER_TYPE(u32)); ++ ++ key[0] = hash & (BIT(BLOOM_FILTER_SHIFT) - 1); ++ key[1] = hash >> BLOOM_FILTER_SHIFT; ++} ++ ++static bool test_bloom_filter(struct lruvec *lruvec, unsigned long seq, void *item) ++{ ++ int key[2]; ++ unsigned long *filter; ++ int gen = filter_gen_from_seq(seq); ++ ++ filter = READ_ONCE(lruvec->mm_state.filters[gen]); ++ if (!filter) ++ return true; ++ ++ get_item_key(item, key); ++ ++ return test_bit(key[0], filter) && test_bit(key[1], filter); ++} ++ ++static void update_bloom_filter(struct lruvec *lruvec, unsigned long seq, void *item) ++{ ++ int key[2]; ++ unsigned long *filter; ++ int gen = filter_gen_from_seq(seq); ++ ++ filter = READ_ONCE(lruvec->mm_state.filters[gen]); ++ if (!filter) ++ return; ++ ++ get_item_key(item, key); ++ ++ if (!test_bit(key[0], filter)) ++ set_bit(key[0], filter); ++ if (!test_bit(key[1], filter)) ++ set_bit(key[1], filter); ++} ++ ++static void reset_bloom_filter(struct lruvec *lruvec, unsigned long seq) ++{ ++ unsigned long *filter; ++ int gen = filter_gen_from_seq(seq); ++ ++ filter = lruvec->mm_state.filters[gen]; ++ if (filter) { ++ bitmap_clear(filter, 0, BIT(BLOOM_FILTER_SHIFT)); ++ return; ++ } ++ ++ filter = bitmap_zalloc(BIT(BLOOM_FILTER_SHIFT), ++ __GFP_HIGH | __GFP_NOMEMALLOC | __GFP_NOWARN); ++ WRITE_ONCE(lruvec->mm_state.filters[gen], filter); ++} ++ + /****************************************************************************** + * mm_struct list + ******************************************************************************/ +@@ -3333,94 +3425,6 @@ void lru_gen_migrate_mm(struct mm_struct *mm) + } + #endif + +-/* +- * Bloom filters with m=1<<15, k=2 and the false positive rates of ~1/5 when +- * n=10,000 and ~1/2 when n=20,000, where, conventionally, m is the number of +- * bits in a bitmap, k is the number of hash functions and n is the number of +- * inserted items. +- * +- * Page table walkers use one of the two filters to reduce their search space. +- * To get rid of non-leaf entries that no longer have enough leaf entries, the +- * aging uses the double-buffering technique to flip to the other filter each +- * time it produces a new generation. For non-leaf entries that have enough +- * leaf entries, the aging carries them over to the next generation in +- * walk_pmd_range(); the eviction also report them when walking the rmap +- * in lru_gen_look_around(). +- * +- * For future optimizations: +- * 1. It's not necessary to keep both filters all the time. The spare one can be +- * freed after the RCU grace period and reallocated if needed again. +- * 2. And when reallocating, it's worth scaling its size according to the number +- * of inserted entries in the other filter, to reduce the memory overhead on +- * small systems and false positives on large systems. +- * 3. Jenkins' hash function is an alternative to Knuth's. +- */ +-#define BLOOM_FILTER_SHIFT 15 +- +-static inline int filter_gen_from_seq(unsigned long seq) +-{ +- return seq % NR_BLOOM_FILTERS; +-} +- +-static void get_item_key(void *item, int *key) +-{ +- u32 hash = hash_ptr(item, BLOOM_FILTER_SHIFT * 2); +- +- BUILD_BUG_ON(BLOOM_FILTER_SHIFT * 2 > BITS_PER_TYPE(u32)); +- +- key[0] = hash & (BIT(BLOOM_FILTER_SHIFT) - 1); +- key[1] = hash >> BLOOM_FILTER_SHIFT; +-} +- +-static void reset_bloom_filter(struct lruvec *lruvec, unsigned long seq) +-{ +- unsigned long *filter; +- int gen = filter_gen_from_seq(seq); +- +- filter = lruvec->mm_state.filters[gen]; +- if (filter) { +- bitmap_clear(filter, 0, BIT(BLOOM_FILTER_SHIFT)); +- return; +- } +- +- filter = bitmap_zalloc(BIT(BLOOM_FILTER_SHIFT), +- __GFP_HIGH | __GFP_NOMEMALLOC | __GFP_NOWARN); +- WRITE_ONCE(lruvec->mm_state.filters[gen], filter); +-} +- +-static void update_bloom_filter(struct lruvec *lruvec, unsigned long seq, void *item) +-{ +- int key[2]; +- unsigned long *filter; +- int gen = filter_gen_from_seq(seq); +- +- filter = READ_ONCE(lruvec->mm_state.filters[gen]); +- if (!filter) +- return; +- +- get_item_key(item, key); +- +- if (!test_bit(key[0], filter)) +- set_bit(key[0], filter); +- if (!test_bit(key[1], filter)) +- set_bit(key[1], filter); +-} +- +-static bool test_bloom_filter(struct lruvec *lruvec, unsigned long seq, void *item) +-{ +- int key[2]; +- unsigned long *filter; +- int gen = filter_gen_from_seq(seq); +- +- filter = READ_ONCE(lruvec->mm_state.filters[gen]); +- if (!filter) +- return true; +- +- get_item_key(item, key); +- +- return test_bit(key[0], filter) && test_bit(key[1], filter); +-} +- + static void reset_mm_stats(struct lruvec *lruvec, struct lru_gen_mm_walk *walk, bool last) + { + int i; +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-15-UPSTREAM-mm-multi-gen-LRU-section-for-memcg-LRU.patch b/target/linux/generic/backport-6.1/020-v6.3-15-UPSTREAM-mm-multi-gen-LRU-section-for-memcg-LRU.patch new file mode 100644 index 0000000000..c26e28c3ca --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-15-UPSTREAM-mm-multi-gen-LRU-section-for-memcg-LRU.patch @@ -0,0 +1,440 @@ +From 48c916b812652f9453be5bd45a703728926d41ca Mon Sep 17 00:00:00 2001 +From: "T.J. Alumbaugh" +Date: Wed, 18 Jan 2023 00:18:24 +0000 +Subject: [PATCH 15/19] UPSTREAM: mm: multi-gen LRU: section for memcg LRU + +Move memcg LRU code into a dedicated section. Improve the design doc to +outline its architecture. + +Link: https://lkml.kernel.org/r/20230118001827.1040870-5-talumbau@google.com +Change-Id: Id252e420cff7a858acb098cf2b3642da5c40f602 +Signed-off-by: T.J. Alumbaugh +Cc: Yu Zhao +Signed-off-by: Andrew Morton +(cherry picked from commit 36c7b4db7c942ae9e1b111f0c6b468c8b2e33842) +Bug: 274865848 +Signed-off-by: T.J. Mercier +--- + Documentation/mm/multigen_lru.rst | 33 +++- + include/linux/mm_inline.h | 17 -- + include/linux/mmzone.h | 13 +- + mm/memcontrol.c | 8 +- + mm/vmscan.c | 250 +++++++++++++++++------------- + 5 files changed, 178 insertions(+), 143 deletions(-) + +diff --git a/Documentation/mm/multigen_lru.rst b/Documentation/mm/multigen_lru.rst +index 770b5d539856c..5f1f6ecbb79b9 100644 +--- a/Documentation/mm/multigen_lru.rst ++++ b/Documentation/mm/multigen_lru.rst +@@ -186,9 +186,40 @@ is false positive, the cost is an additional scan of a range of PTEs, + which may yield hot pages anyway. Parameters of the filter itself can + control the false positive rate in the limit. + ++Memcg LRU ++--------- ++An memcg LRU is a per-node LRU of memcgs. It is also an LRU of LRUs, ++since each node and memcg combination has an LRU of folios (see ++``mem_cgroup_lruvec()``). Its goal is to improve the scalability of ++global reclaim, which is critical to system-wide memory overcommit in ++data centers. Note that memcg LRU only applies to global reclaim. ++ ++The basic structure of an memcg LRU can be understood by an analogy to ++the active/inactive LRU (of folios): ++ ++1. It has the young and the old (generations), i.e., the counterparts ++ to the active and the inactive; ++2. The increment of ``max_seq`` triggers promotion, i.e., the ++ counterpart to activation; ++3. Other events trigger similar operations, e.g., offlining an memcg ++ triggers demotion, i.e., the counterpart to deactivation. ++ ++In terms of global reclaim, it has two distinct features: ++ ++1. Sharding, which allows each thread to start at a random memcg (in ++ the old generation) and improves parallelism; ++2. Eventual fairness, which allows direct reclaim to bail out at will ++ and reduces latency without affecting fairness over some time. ++ ++In terms of traversing memcgs during global reclaim, it improves the ++best-case complexity from O(n) to O(1) and does not affect the ++worst-case complexity O(n). Therefore, on average, it has a sublinear ++complexity. ++ + Summary + ------- +-The multi-gen LRU can be disassembled into the following parts: ++The multi-gen LRU (of folios) can be disassembled into the following ++parts: + + * Generations + * Rmap walks +diff --git a/include/linux/mm_inline.h b/include/linux/mm_inline.h +index 9a8e2049333c0..5567f4850243b 100644 +--- a/include/linux/mm_inline.h ++++ b/include/linux/mm_inline.h +@@ -122,18 +122,6 @@ static inline bool lru_gen_in_fault(void) + return current->in_lru_fault; + } + +-#ifdef CONFIG_MEMCG +-static inline int lru_gen_memcg_seg(struct lruvec *lruvec) +-{ +- return READ_ONCE(lruvec->lrugen.seg); +-} +-#else +-static inline int lru_gen_memcg_seg(struct lruvec *lruvec) +-{ +- return 0; +-} +-#endif +- + static inline int lru_gen_from_seq(unsigned long seq) + { + return seq % MAX_NR_GENS; +@@ -309,11 +297,6 @@ static inline bool lru_gen_in_fault(void) + return false; + } + +-static inline int lru_gen_memcg_seg(struct lruvec *lruvec) +-{ +- return 0; +-} +- + static inline bool lru_gen_add_folio(struct lruvec *lruvec, struct folio *folio, bool reclaiming) + { + return false; +diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h +index 66e067a635682..403c7461e7a70 100644 +--- a/include/linux/mmzone.h ++++ b/include/linux/mmzone.h +@@ -368,15 +368,6 @@ struct page_vma_mapped_walk; + #define LRU_GEN_MASK ((BIT(LRU_GEN_WIDTH) - 1) << LRU_GEN_PGOFF) + #define LRU_REFS_MASK ((BIT(LRU_REFS_WIDTH) - 1) << LRU_REFS_PGOFF) + +-/* see the comment on MEMCG_NR_GENS */ +-enum { +- MEMCG_LRU_NOP, +- MEMCG_LRU_HEAD, +- MEMCG_LRU_TAIL, +- MEMCG_LRU_OLD, +- MEMCG_LRU_YOUNG, +-}; +- + #ifdef CONFIG_LRU_GEN + + enum { +@@ -557,7 +548,7 @@ void lru_gen_exit_memcg(struct mem_cgroup *memcg); + void lru_gen_online_memcg(struct mem_cgroup *memcg); + void lru_gen_offline_memcg(struct mem_cgroup *memcg); + void lru_gen_release_memcg(struct mem_cgroup *memcg); +-void lru_gen_rotate_memcg(struct lruvec *lruvec, int op); ++void lru_gen_soft_reclaim(struct lruvec *lruvec); + + #else /* !CONFIG_MEMCG */ + +@@ -608,7 +599,7 @@ static inline void lru_gen_release_memcg(struct mem_cgroup *memcg) + { + } + +-static inline void lru_gen_rotate_memcg(struct lruvec *lruvec, int op) ++static inline void lru_gen_soft_reclaim(struct lruvec *lruvec) + { + } + +diff --git a/mm/memcontrol.c b/mm/memcontrol.c +index 7815d556e38cc..5397aeb43986d 100644 +--- a/mm/memcontrol.c ++++ b/mm/memcontrol.c +@@ -478,12 +478,8 @@ static void mem_cgroup_update_tree(struct mem_cgroup *memcg, int nid) + struct mem_cgroup_tree_per_node *mctz; + + if (lru_gen_enabled()) { +- struct lruvec *lruvec = &memcg->nodeinfo[nid]->lruvec; +- +- /* see the comment on MEMCG_NR_GENS */ +- if (soft_limit_excess(memcg) && lru_gen_memcg_seg(lruvec) != MEMCG_LRU_HEAD) +- lru_gen_rotate_memcg(lruvec, MEMCG_LRU_HEAD); +- ++ if (soft_limit_excess(memcg)) ++ lru_gen_soft_reclaim(&memcg->nodeinfo[nid]->lruvec); + return; + } + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 74b4f9d660b56..ccde215c084ca 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -4689,6 +4689,148 @@ void lru_gen_look_around(struct page_vma_mapped_walk *pvmw) + mem_cgroup_unlock_pages(); + } + ++/****************************************************************************** ++ * memcg LRU ++ ******************************************************************************/ ++ ++/* see the comment on MEMCG_NR_GENS */ ++enum { ++ MEMCG_LRU_NOP, ++ MEMCG_LRU_HEAD, ++ MEMCG_LRU_TAIL, ++ MEMCG_LRU_OLD, ++ MEMCG_LRU_YOUNG, ++}; ++ ++#ifdef CONFIG_MEMCG ++ ++static int lru_gen_memcg_seg(struct lruvec *lruvec) ++{ ++ return READ_ONCE(lruvec->lrugen.seg); ++} ++ ++static void lru_gen_rotate_memcg(struct lruvec *lruvec, int op) ++{ ++ int seg; ++ int old, new; ++ int bin = get_random_u32_below(MEMCG_NR_BINS); ++ struct pglist_data *pgdat = lruvec_pgdat(lruvec); ++ ++ spin_lock(&pgdat->memcg_lru.lock); ++ ++ VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); ++ ++ seg = 0; ++ new = old = lruvec->lrugen.gen; ++ ++ /* see the comment on MEMCG_NR_GENS */ ++ if (op == MEMCG_LRU_HEAD) ++ seg = MEMCG_LRU_HEAD; ++ else if (op == MEMCG_LRU_TAIL) ++ seg = MEMCG_LRU_TAIL; ++ else if (op == MEMCG_LRU_OLD) ++ new = get_memcg_gen(pgdat->memcg_lru.seq); ++ else if (op == MEMCG_LRU_YOUNG) ++ new = get_memcg_gen(pgdat->memcg_lru.seq + 1); ++ else ++ VM_WARN_ON_ONCE(true); ++ ++ hlist_nulls_del_rcu(&lruvec->lrugen.list); ++ ++ if (op == MEMCG_LRU_HEAD || op == MEMCG_LRU_OLD) ++ hlist_nulls_add_head_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[new][bin]); ++ else ++ hlist_nulls_add_tail_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[new][bin]); ++ ++ pgdat->memcg_lru.nr_memcgs[old]--; ++ pgdat->memcg_lru.nr_memcgs[new]++; ++ ++ lruvec->lrugen.gen = new; ++ WRITE_ONCE(lruvec->lrugen.seg, seg); ++ ++ if (!pgdat->memcg_lru.nr_memcgs[old] && old == get_memcg_gen(pgdat->memcg_lru.seq)) ++ WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); ++ ++ spin_unlock(&pgdat->memcg_lru.lock); ++} ++ ++void lru_gen_online_memcg(struct mem_cgroup *memcg) ++{ ++ int gen; ++ int nid; ++ int bin = get_random_u32_below(MEMCG_NR_BINS); ++ ++ for_each_node(nid) { ++ struct pglist_data *pgdat = NODE_DATA(nid); ++ struct lruvec *lruvec = get_lruvec(memcg, nid); ++ ++ spin_lock(&pgdat->memcg_lru.lock); ++ ++ VM_WARN_ON_ONCE(!hlist_nulls_unhashed(&lruvec->lrugen.list)); ++ ++ gen = get_memcg_gen(pgdat->memcg_lru.seq); ++ ++ hlist_nulls_add_tail_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[gen][bin]); ++ pgdat->memcg_lru.nr_memcgs[gen]++; ++ ++ lruvec->lrugen.gen = gen; ++ ++ spin_unlock(&pgdat->memcg_lru.lock); ++ } ++} ++ ++void lru_gen_offline_memcg(struct mem_cgroup *memcg) ++{ ++ int nid; ++ ++ for_each_node(nid) { ++ struct lruvec *lruvec = get_lruvec(memcg, nid); ++ ++ lru_gen_rotate_memcg(lruvec, MEMCG_LRU_OLD); ++ } ++} ++ ++void lru_gen_release_memcg(struct mem_cgroup *memcg) ++{ ++ int gen; ++ int nid; ++ ++ for_each_node(nid) { ++ struct pglist_data *pgdat = NODE_DATA(nid); ++ struct lruvec *lruvec = get_lruvec(memcg, nid); ++ ++ spin_lock(&pgdat->memcg_lru.lock); ++ ++ VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); ++ ++ gen = lruvec->lrugen.gen; ++ ++ hlist_nulls_del_rcu(&lruvec->lrugen.list); ++ pgdat->memcg_lru.nr_memcgs[gen]--; ++ ++ if (!pgdat->memcg_lru.nr_memcgs[gen] && gen == get_memcg_gen(pgdat->memcg_lru.seq)) ++ WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); ++ ++ spin_unlock(&pgdat->memcg_lru.lock); ++ } ++} ++ ++void lru_gen_soft_reclaim(struct lruvec *lruvec) ++{ ++ /* see the comment on MEMCG_NR_GENS */ ++ if (lru_gen_memcg_seg(lruvec) != MEMCG_LRU_HEAD) ++ lru_gen_rotate_memcg(lruvec, MEMCG_LRU_HEAD); ++} ++ ++#else /* !CONFIG_MEMCG */ ++ ++static int lru_gen_memcg_seg(struct lruvec *lruvec) ++{ ++ return 0; ++} ++ ++#endif ++ + /****************************************************************************** + * the eviction + ******************************************************************************/ +@@ -5386,53 +5528,6 @@ static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control * + pgdat->kswapd_failures = 0; + } + +-#ifdef CONFIG_MEMCG +-void lru_gen_rotate_memcg(struct lruvec *lruvec, int op) +-{ +- int seg; +- int old, new; +- int bin = get_random_u32_below(MEMCG_NR_BINS); +- struct pglist_data *pgdat = lruvec_pgdat(lruvec); +- +- spin_lock(&pgdat->memcg_lru.lock); +- +- VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); +- +- seg = 0; +- new = old = lruvec->lrugen.gen; +- +- /* see the comment on MEMCG_NR_GENS */ +- if (op == MEMCG_LRU_HEAD) +- seg = MEMCG_LRU_HEAD; +- else if (op == MEMCG_LRU_TAIL) +- seg = MEMCG_LRU_TAIL; +- else if (op == MEMCG_LRU_OLD) +- new = get_memcg_gen(pgdat->memcg_lru.seq); +- else if (op == MEMCG_LRU_YOUNG) +- new = get_memcg_gen(pgdat->memcg_lru.seq + 1); +- else +- VM_WARN_ON_ONCE(true); +- +- hlist_nulls_del_rcu(&lruvec->lrugen.list); +- +- if (op == MEMCG_LRU_HEAD || op == MEMCG_LRU_OLD) +- hlist_nulls_add_head_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[new][bin]); +- else +- hlist_nulls_add_tail_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[new][bin]); +- +- pgdat->memcg_lru.nr_memcgs[old]--; +- pgdat->memcg_lru.nr_memcgs[new]++; +- +- lruvec->lrugen.gen = new; +- WRITE_ONCE(lruvec->lrugen.seg, seg); +- +- if (!pgdat->memcg_lru.nr_memcgs[old] && old == get_memcg_gen(pgdat->memcg_lru.seq)) +- WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); +- +- spin_unlock(&pgdat->memcg_lru.lock); +-} +-#endif +- + /****************************************************************************** + * state change + ******************************************************************************/ +@@ -6078,67 +6173,6 @@ void lru_gen_exit_memcg(struct mem_cgroup *memcg) + } + } + +-void lru_gen_online_memcg(struct mem_cgroup *memcg) +-{ +- int gen; +- int nid; +- int bin = get_random_u32_below(MEMCG_NR_BINS); +- +- for_each_node(nid) { +- struct pglist_data *pgdat = NODE_DATA(nid); +- struct lruvec *lruvec = get_lruvec(memcg, nid); +- +- spin_lock(&pgdat->memcg_lru.lock); +- +- VM_WARN_ON_ONCE(!hlist_nulls_unhashed(&lruvec->lrugen.list)); +- +- gen = get_memcg_gen(pgdat->memcg_lru.seq); +- +- hlist_nulls_add_tail_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[gen][bin]); +- pgdat->memcg_lru.nr_memcgs[gen]++; +- +- lruvec->lrugen.gen = gen; +- +- spin_unlock(&pgdat->memcg_lru.lock); +- } +-} +- +-void lru_gen_offline_memcg(struct mem_cgroup *memcg) +-{ +- int nid; +- +- for_each_node(nid) { +- struct lruvec *lruvec = get_lruvec(memcg, nid); +- +- lru_gen_rotate_memcg(lruvec, MEMCG_LRU_OLD); +- } +-} +- +-void lru_gen_release_memcg(struct mem_cgroup *memcg) +-{ +- int gen; +- int nid; +- +- for_each_node(nid) { +- struct pglist_data *pgdat = NODE_DATA(nid); +- struct lruvec *lruvec = get_lruvec(memcg, nid); +- +- spin_lock(&pgdat->memcg_lru.lock); +- +- VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); +- +- gen = lruvec->lrugen.gen; +- +- hlist_nulls_del_rcu(&lruvec->lrugen.list); +- pgdat->memcg_lru.nr_memcgs[gen]--; +- +- if (!pgdat->memcg_lru.nr_memcgs[gen] && gen == get_memcg_gen(pgdat->memcg_lru.seq)) +- WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); +- +- spin_unlock(&pgdat->memcg_lru.lock); +- } +-} +- + #endif /* CONFIG_MEMCG */ + + static int __init init_lru_gen(void) +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-16-UPSTREAM-mm-multi-gen-LRU-improve-lru_gen_exit_memcg.patch b/target/linux/generic/backport-6.1/020-v6.3-16-UPSTREAM-mm-multi-gen-LRU-improve-lru_gen_exit_memcg.patch new file mode 100644 index 0000000000..1f3f8ffe6d --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-16-UPSTREAM-mm-multi-gen-LRU-improve-lru_gen_exit_memcg.patch @@ -0,0 +1,45 @@ +From bec433f29537652ed054148edfd7e2183ddcf7c3 Mon Sep 17 00:00:00 2001 +From: "T.J. Alumbaugh" +Date: Wed, 18 Jan 2023 00:18:25 +0000 +Subject: [PATCH 16/19] UPSTREAM: mm: multi-gen LRU: improve + lru_gen_exit_memcg() + +Add warnings and poison ->next. + +Link: https://lkml.kernel.org/r/20230118001827.1040870-6-talumbau@google.com +Change-Id: I53de9e04c1ae941e122b33cd45d2bbb5f34aae0c +Signed-off-by: T.J. Alumbaugh +Cc: Yu Zhao +Signed-off-by: Andrew Morton +(cherry picked from commit 37cc99979d04cca677c0ad5c0acd1149ec165d1b) +Bug: 274865848 +Signed-off-by: T.J. Mercier +--- + mm/vmscan.c | 5 +++++ + 1 file changed, 5 insertions(+) + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index ccde215c084ca..d5d6f8d94f58a 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -6160,12 +6160,17 @@ void lru_gen_exit_memcg(struct mem_cgroup *memcg) + int i; + int nid; + ++ VM_WARN_ON_ONCE(!list_empty(&memcg->mm_list.fifo)); ++ + for_each_node(nid) { + struct lruvec *lruvec = get_lruvec(memcg, nid); + ++ VM_WARN_ON_ONCE(lruvec->mm_state.nr_walkers); + VM_WARN_ON_ONCE(memchr_inv(lruvec->lrugen.nr_pages, 0, + sizeof(lruvec->lrugen.nr_pages))); + ++ lruvec->lrugen.list.next = LIST_POISON1; ++ + for (i = 0; i < NR_BLOOM_FILTERS; i++) { + bitmap_free(lruvec->mm_state.filters[i]); + lruvec->mm_state.filters[i] = NULL; +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-17-UPSTREAM-mm-multi-gen-LRU-improve-walk_pmd_range.patch b/target/linux/generic/backport-6.1/020-v6.3-17-UPSTREAM-mm-multi-gen-LRU-improve-walk_pmd_range.patch new file mode 100644 index 0000000000..02dd920e54 --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-17-UPSTREAM-mm-multi-gen-LRU-improve-walk_pmd_range.patch @@ -0,0 +1,140 @@ +From fc0e3b06e0f19917b7ecad7967a72f61d4743644 Mon Sep 17 00:00:00 2001 +From: "T.J. Alumbaugh" +Date: Wed, 18 Jan 2023 00:18:26 +0000 +Subject: [PATCH 17/19] UPSTREAM: mm: multi-gen LRU: improve walk_pmd_range() + +Improve readability of walk_pmd_range() and walk_pmd_range_locked(). + +Link: https://lkml.kernel.org/r/20230118001827.1040870-7-talumbau@google.com +Change-Id: Ia084fbf53fe989673b7804ca8ca520af12d7d52a +Signed-off-by: T.J. Alumbaugh +Cc: Yu Zhao +Signed-off-by: Andrew Morton +(cherry picked from commit b5ff4133617d0eced35b685da0bd0929dd9fabb7) +Bug: 274865848 +Signed-off-by: T.J. Mercier +--- + mm/vmscan.c | 40 ++++++++++++++++++++-------------------- + 1 file changed, 20 insertions(+), 20 deletions(-) + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index d5d6f8d94f58a..8f496c2e670a9 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -3980,8 +3980,8 @@ static bool walk_pte_range(pmd_t *pmd, unsigned long start, unsigned long end, + } + + #if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG) +-static void walk_pmd_range_locked(pud_t *pud, unsigned long next, struct vm_area_struct *vma, +- struct mm_walk *args, unsigned long *bitmap, unsigned long *start) ++static void walk_pmd_range_locked(pud_t *pud, unsigned long addr, struct vm_area_struct *vma, ++ struct mm_walk *args, unsigned long *bitmap, unsigned long *first) + { + int i; + pmd_t *pmd; +@@ -3994,18 +3994,19 @@ static void walk_pmd_range_locked(pud_t *pud, unsigned long next, struct vm_area + VM_WARN_ON_ONCE(pud_leaf(*pud)); + + /* try to batch at most 1+MIN_LRU_BATCH+1 entries */ +- if (*start == -1) { +- *start = next; ++ if (*first == -1) { ++ *first = addr; ++ bitmap_zero(bitmap, MIN_LRU_BATCH); + return; + } + +- i = next == -1 ? 0 : pmd_index(next) - pmd_index(*start); ++ i = addr == -1 ? 0 : pmd_index(addr) - pmd_index(*first); + if (i && i <= MIN_LRU_BATCH) { + __set_bit(i - 1, bitmap); + return; + } + +- pmd = pmd_offset(pud, *start); ++ pmd = pmd_offset(pud, *first); + + ptl = pmd_lockptr(args->mm, pmd); + if (!spin_trylock(ptl)) +@@ -4016,15 +4017,16 @@ static void walk_pmd_range_locked(pud_t *pud, unsigned long next, struct vm_area + do { + unsigned long pfn; + struct folio *folio; +- unsigned long addr = i ? (*start & PMD_MASK) + i * PMD_SIZE : *start; ++ ++ /* don't round down the first address */ ++ addr = i ? (*first & PMD_MASK) + i * PMD_SIZE : *first; + + pfn = get_pmd_pfn(pmd[i], vma, addr); + if (pfn == -1) + goto next; + + if (!pmd_trans_huge(pmd[i])) { +- if (arch_has_hw_nonleaf_pmd_young() && +- get_cap(LRU_GEN_NONLEAF_YOUNG)) ++ if (arch_has_hw_nonleaf_pmd_young() && get_cap(LRU_GEN_NONLEAF_YOUNG)) + pmdp_test_and_clear_young(vma, addr, pmd + i); + goto next; + } +@@ -4053,12 +4055,11 @@ static void walk_pmd_range_locked(pud_t *pud, unsigned long next, struct vm_area + arch_leave_lazy_mmu_mode(); + spin_unlock(ptl); + done: +- *start = -1; +- bitmap_zero(bitmap, MIN_LRU_BATCH); ++ *first = -1; + } + #else +-static void walk_pmd_range_locked(pud_t *pud, unsigned long next, struct vm_area_struct *vma, +- struct mm_walk *args, unsigned long *bitmap, unsigned long *start) ++static void walk_pmd_range_locked(pud_t *pud, unsigned long addr, struct vm_area_struct *vma, ++ struct mm_walk *args, unsigned long *bitmap, unsigned long *first) + { + } + #endif +@@ -4071,9 +4072,9 @@ static void walk_pmd_range(pud_t *pud, unsigned long start, unsigned long end, + unsigned long next; + unsigned long addr; + struct vm_area_struct *vma; +- unsigned long pos = -1; ++ unsigned long bitmap[BITS_TO_LONGS(MIN_LRU_BATCH)]; ++ unsigned long first = -1; + struct lru_gen_mm_walk *walk = args->private; +- unsigned long bitmap[BITS_TO_LONGS(MIN_LRU_BATCH)] = {}; + + VM_WARN_ON_ONCE(pud_leaf(*pud)); + +@@ -4115,18 +4116,17 @@ static void walk_pmd_range(pud_t *pud, unsigned long start, unsigned long end, + if (pfn < pgdat->node_start_pfn || pfn >= pgdat_end_pfn(pgdat)) + continue; + +- walk_pmd_range_locked(pud, addr, vma, args, bitmap, &pos); ++ walk_pmd_range_locked(pud, addr, vma, args, bitmap, &first); + continue; + } + #endif + walk->mm_stats[MM_NONLEAF_TOTAL]++; + +- if (arch_has_hw_nonleaf_pmd_young() && +- get_cap(LRU_GEN_NONLEAF_YOUNG)) { ++ if (arch_has_hw_nonleaf_pmd_young() && get_cap(LRU_GEN_NONLEAF_YOUNG)) { + if (!pmd_young(val)) + continue; + +- walk_pmd_range_locked(pud, addr, vma, args, bitmap, &pos); ++ walk_pmd_range_locked(pud, addr, vma, args, bitmap, &first); + } + + if (!walk->force_scan && !test_bloom_filter(walk->lruvec, walk->max_seq, pmd + i)) +@@ -4143,7 +4143,7 @@ static void walk_pmd_range(pud_t *pud, unsigned long start, unsigned long end, + update_bloom_filter(walk->lruvec, walk->max_seq + 1, pmd + i); + } + +- walk_pmd_range_locked(pud, -1, vma, args, bitmap, &pos); ++ walk_pmd_range_locked(pud, -1, vma, args, bitmap, &first); + + if (i < PTRS_PER_PMD && get_next_vma(PUD_MASK, PMD_SIZE, args, &start, &end)) + goto restart; +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-18-UPSTREAM-mm-multi-gen-LRU-simplify-lru_gen_look_arou.patch b/target/linux/generic/backport-6.1/020-v6.3-18-UPSTREAM-mm-multi-gen-LRU-simplify-lru_gen_look_arou.patch new file mode 100644 index 0000000000..caee6b096f --- /dev/null +++ b/target/linux/generic/backport-6.1/020-v6.3-18-UPSTREAM-mm-multi-gen-LRU-simplify-lru_gen_look_arou.patch @@ -0,0 +1,153 @@ +From e604c3ccb4dfbdde2467fccef9bb36170a392695 Mon Sep 17 00:00:00 2001 +From: "T.J. Alumbaugh" +Date: Wed, 18 Jan 2023 00:18:27 +0000 +Subject: [PATCH 18/19] UPSTREAM: mm: multi-gen LRU: simplify + lru_gen_look_around() + +Update the folio generation in place with or without +current->reclaim_state->mm_walk. The LRU lock is held for longer, if +mm_walk is NULL and the number of folios to update is more than +PAGEVEC_SIZE. + +This causes a measurable regression from the LRU lock contention during a +microbencmark. But a tiny regression is not worth the complexity. + +Link: https://lkml.kernel.org/r/20230118001827.1040870-8-talumbau@google.com +Change-Id: I9ce18b4f4062e6c1c13c98ece9422478eb8e1846 +Signed-off-by: T.J. Alumbaugh +Cc: Yu Zhao +Signed-off-by: Andrew Morton +(cherry picked from commit abf086721a2f1e6897c57796f7268df1b194c750) +Bug: 274865848 +Signed-off-by: T.J. Mercier +--- + mm/vmscan.c | 73 +++++++++++++++++------------------------------------ + 1 file changed, 23 insertions(+), 50 deletions(-) + +diff --git a/mm/vmscan.c b/mm/vmscan.c +index 8f496c2e670a9..f6ce7a1fd78a3 100644 +--- a/mm/vmscan.c ++++ b/mm/vmscan.c +@@ -4571,13 +4571,12 @@ static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) + void lru_gen_look_around(struct page_vma_mapped_walk *pvmw) + { + int i; +- pte_t *pte; + unsigned long start; + unsigned long end; +- unsigned long addr; + struct lru_gen_mm_walk *walk; + int young = 0; +- unsigned long bitmap[BITS_TO_LONGS(MIN_LRU_BATCH)] = {}; ++ pte_t *pte = pvmw->pte; ++ unsigned long addr = pvmw->address; + struct folio *folio = pfn_folio(pvmw->pfn); + struct mem_cgroup *memcg = folio_memcg(folio); + struct pglist_data *pgdat = folio_pgdat(folio); +@@ -4594,25 +4593,28 @@ void lru_gen_look_around(struct page_vma_mapped_walk *pvmw) + /* avoid taking the LRU lock under the PTL when possible */ + walk = current->reclaim_state ? current->reclaim_state->mm_walk : NULL; + +- start = max(pvmw->address & PMD_MASK, pvmw->vma->vm_start); +- end = min(pvmw->address | ~PMD_MASK, pvmw->vma->vm_end - 1) + 1; ++ start = max(addr & PMD_MASK, pvmw->vma->vm_start); ++ end = min(addr | ~PMD_MASK, pvmw->vma->vm_end - 1) + 1; + + if (end - start > MIN_LRU_BATCH * PAGE_SIZE) { +- if (pvmw->address - start < MIN_LRU_BATCH * PAGE_SIZE / 2) ++ if (addr - start < MIN_LRU_BATCH * PAGE_SIZE / 2) + end = start + MIN_LRU_BATCH * PAGE_SIZE; +- else if (end - pvmw->address < MIN_LRU_BATCH * PAGE_SIZE / 2) ++ else if (end - addr < MIN_LRU_BATCH * PAGE_SIZE / 2) + start = end - MIN_LRU_BATCH * PAGE_SIZE; + else { +- start = pvmw->address - MIN_LRU_BATCH * PAGE_SIZE / 2; +- end = pvmw->address + MIN_LRU_BATCH * PAGE_SIZE / 2; ++ start = addr - MIN_LRU_BATCH * PAGE_SIZE / 2; ++ end = addr + MIN_LRU_BATCH * PAGE_SIZE / 2; + } + } + +- pte = pvmw->pte - (pvmw->address - start) / PAGE_SIZE; ++ /* folio_update_gen() requires stable folio_memcg() */ ++ if (!mem_cgroup_trylock_pages(memcg)) ++ return; + +- rcu_read_lock(); + arch_enter_lazy_mmu_mode(); + ++ pte -= (addr - start) / PAGE_SIZE; ++ + for (i = 0, addr = start; addr != end; i++, addr += PAGE_SIZE) { + unsigned long pfn; + +@@ -4637,56 +4639,27 @@ void lru_gen_look_around(struct page_vma_mapped_walk *pvmw) + !folio_test_swapcache(folio))) + folio_mark_dirty(folio); + ++ if (walk) { ++ old_gen = folio_update_gen(folio, new_gen); ++ if (old_gen >= 0 && old_gen != new_gen) ++ update_batch_size(walk, folio, old_gen, new_gen); ++ ++ continue; ++ } ++ + old_gen = folio_lru_gen(folio); + if (old_gen < 0) + folio_set_referenced(folio); + else if (old_gen != new_gen) +- __set_bit(i, bitmap); ++ folio_activate(folio); + } + + arch_leave_lazy_mmu_mode(); +- rcu_read_unlock(); ++ mem_cgroup_unlock_pages(); + + /* feedback from rmap walkers to page table walkers */ + if (suitable_to_scan(i, young)) + update_bloom_filter(lruvec, max_seq, pvmw->pmd); +- +- if (!walk && bitmap_weight(bitmap, MIN_LRU_BATCH) < PAGEVEC_SIZE) { +- for_each_set_bit(i, bitmap, MIN_LRU_BATCH) { +- folio = pfn_folio(pte_pfn(pte[i])); +- folio_activate(folio); +- } +- return; +- } +- +- /* folio_update_gen() requires stable folio_memcg() */ +- if (!mem_cgroup_trylock_pages(memcg)) +- return; +- +- if (!walk) { +- spin_lock_irq(&lruvec->lru_lock); +- new_gen = lru_gen_from_seq(lruvec->lrugen.max_seq); +- } +- +- for_each_set_bit(i, bitmap, MIN_LRU_BATCH) { +- folio = pfn_folio(pte_pfn(pte[i])); +- if (folio_memcg_rcu(folio) != memcg) +- continue; +- +- old_gen = folio_update_gen(folio, new_gen); +- if (old_gen < 0 || old_gen == new_gen) +- continue; +- +- if (walk) +- update_batch_size(walk, folio, old_gen, new_gen); +- else +- lru_gen_update_size(lruvec, folio, old_gen, new_gen); +- } +- +- if (!walk) +- spin_unlock_irq(&lruvec->lru_lock); +- +- mem_cgroup_unlock_pages(); + } + + /****************************************************************************** +-- +2.40.1 + diff --git a/target/linux/generic/backport-6.1/020-v6.3-19-mm-add-vma_has_recency.patch b/target/linux/generic/backport-6.1/020-v6.3-19-mm-add-vma_has_recency.patch deleted file mode 100644 index 5335b80488..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-19-mm-add-vma_has_recency.patch +++ /dev/null @@ -1,187 +0,0 @@ -From 6c7f552a48b49a8612786a28a2239fbc24fac289 Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Fri, 30 Dec 2022 14:52:51 -0700 -Subject: [PATCH 19/29] mm: add vma_has_recency() - -Add vma_has_recency() to indicate whether a VMA may exhibit temporal -locality that the LRU algorithm relies on. - -This function returns false for VMAs marked by VM_SEQ_READ or -VM_RAND_READ. While the former flag indicates linear access, i.e., a -special case of spatial locality, both flags indicate a lack of temporal -locality, i.e., the reuse of an area within a relatively small duration. - -"Recency" is chosen over "locality" to avoid confusion between temporal -and spatial localities. - -Before this patch, the active/inactive LRU only ignored the accessed bit -from VMAs marked by VM_SEQ_READ. After this patch, the active/inactive -LRU and MGLRU share the same logic: they both ignore the accessed bit if -vma_has_recency() returns false. - -For the active/inactive LRU, the following fio test showed a [6, 8]% -increase in IOPS when randomly accessing mapped files under memory -pressure. - - kb=$(awk '/MemTotal/ { print $2 }' /proc/meminfo) - kb=$((kb - 8*1024*1024)) - - modprobe brd rd_nr=1 rd_size=$kb - dd if=/dev/zero of=/dev/ram0 bs=1M - - mkfs.ext4 /dev/ram0 - mount /dev/ram0 /mnt/ - swapoff -a - - fio --name=test --directory=/mnt/ --ioengine=mmap --numjobs=8 \ - --size=8G --rw=randrw --time_based --runtime=10m \ - --group_reporting - -The discussion that led to this patch is here [1]. Additional test -results are available in that thread. - -[1] https://lore.kernel.org/r/Y31s%2FK8T85jh05wH@google.com/ - -Link: https://lkml.kernel.org/r/20221230215252.2628425-1-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Alexander Viro -Cc: Andrea Righi -Cc: Johannes Weiner -Cc: Michael Larabel -Signed-off-by: Andrew Morton ---- - include/linux/mm_inline.h | 9 +++++++++ - mm/memory.c | 8 ++++---- - mm/rmap.c | 42 +++++++++++++++++---------------------- - mm/vmscan.c | 5 ++++- - 4 files changed, 35 insertions(+), 29 deletions(-) - ---- a/include/linux/mm_inline.h -+++ b/include/linux/mm_inline.h -@@ -578,4 +578,12 @@ pte_install_uffd_wp_if_needed(struct vm_ - #endif - } - -+static inline bool vma_has_recency(struct vm_area_struct *vma) -+{ -+ if (vma->vm_flags & (VM_SEQ_READ | VM_RAND_READ)) -+ return false; -+ -+ return true; -+} -+ - #endif ---- a/mm/memory.c -+++ b/mm/memory.c -@@ -1435,8 +1435,7 @@ again: - force_flush = 1; - set_page_dirty(page); - } -- if (pte_young(ptent) && -- likely(!(vma->vm_flags & VM_SEQ_READ))) -+ if (pte_young(ptent) && likely(vma_has_recency(vma))) - mark_page_accessed(page); - } - rss[mm_counter(page)]--; -@@ -5170,8 +5169,8 @@ static inline void mm_account_fault(stru - #ifdef CONFIG_LRU_GEN - static void lru_gen_enter_fault(struct vm_area_struct *vma) - { -- /* the LRU algorithm doesn't apply to sequential or random reads */ -- current->in_lru_fault = !(vma->vm_flags & (VM_SEQ_READ | VM_RAND_READ)); -+ /* the LRU algorithm only applies to accesses with recency */ -+ current->in_lru_fault = vma_has_recency(vma); - } - - static void lru_gen_exit_fault(void) ---- a/mm/rmap.c -+++ b/mm/rmap.c -@@ -823,25 +823,14 @@ static bool folio_referenced_one(struct - } - - if (pvmw.pte) { -- if (lru_gen_enabled() && pte_young(*pvmw.pte) && -- !(vma->vm_flags & (VM_SEQ_READ | VM_RAND_READ))) { -+ if (lru_gen_enabled() && pte_young(*pvmw.pte)) { - lru_gen_look_around(&pvmw); - referenced++; - } - - if (ptep_clear_flush_young_notify(vma, address, -- pvmw.pte)) { -- /* -- * Don't treat a reference through -- * a sequentially read mapping as such. -- * If the folio has been used in another mapping, -- * we will catch it; if this other mapping is -- * already gone, the unmap path will have set -- * the referenced flag or activated the folio. -- */ -- if (likely(!(vma->vm_flags & VM_SEQ_READ))) -- referenced++; -- } -+ pvmw.pte)) -+ referenced++; - } else if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE)) { - if (pmdp_clear_flush_young_notify(vma, address, - pvmw.pmd)) -@@ -875,7 +864,20 @@ static bool invalid_folio_referenced_vma - struct folio_referenced_arg *pra = arg; - struct mem_cgroup *memcg = pra->memcg; - -- if (!mm_match_cgroup(vma->vm_mm, memcg)) -+ /* -+ * Ignore references from this mapping if it has no recency. If the -+ * page has been used in another mapping, we will catch it; if this -+ * other mapping is already gone, the unmap path will have set the -+ * referenced flag or activated the page in zap_pte_range(). -+ */ -+ if (!vma_has_recency(vma)) -+ return true; -+ -+ /* -+ * If we are reclaiming on behalf of a cgroup, skip counting on behalf -+ * of references from different cgroups. -+ */ -+ if (memcg && !mm_match_cgroup(vma->vm_mm, memcg)) - return true; - - return false; -@@ -906,6 +908,7 @@ int folio_referenced(struct folio *folio - .arg = (void *)&pra, - .anon_lock = folio_lock_anon_vma_read, - .try_lock = true, -+ .invalid_vma = invalid_folio_referenced_vma, - }; - - *vm_flags = 0; -@@ -921,15 +924,6 @@ int folio_referenced(struct folio *folio - return 1; - } - -- /* -- * If we are reclaiming on behalf of a cgroup, skip -- * counting on behalf of references from different -- * cgroups -- */ -- if (memcg) { -- rwc.invalid_vma = invalid_folio_referenced_vma; -- } -- - rmap_walk(folio, &rwc); - *vm_flags = pra.vm_flags; - ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -3766,7 +3766,10 @@ static int should_skip_vma(unsigned long - if (is_vm_hugetlb_page(vma)) - return true; - -- if (vma->vm_flags & (VM_LOCKED | VM_SPECIAL | VM_SEQ_READ | VM_RAND_READ)) -+ if (!vma_has_recency(vma)) -+ return true; -+ -+ if (vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) - return true; - - if (vma == get_gate_vma(vma->vm_mm)) diff --git a/target/linux/generic/backport-6.1/020-v6.3-20-mm-support-POSIX_FADV_NOREUSE.patch b/target/linux/generic/backport-6.1/020-v6.3-20-mm-support-POSIX_FADV_NOREUSE.patch deleted file mode 100644 index b2b7c605ca..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-20-mm-support-POSIX_FADV_NOREUSE.patch +++ /dev/null @@ -1,125 +0,0 @@ -From 686c3d4f71de9e0e7a27f03a5617a712385f90cd Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Fri, 30 Dec 2022 14:52:52 -0700 -Subject: [PATCH 20/29] mm: support POSIX_FADV_NOREUSE - -This patch adds POSIX_FADV_NOREUSE to vma_has_recency() so that the LRU -algorithm can ignore access to mapped files marked by this flag. - -The advantages of POSIX_FADV_NOREUSE are: -1. Unlike MADV_SEQUENTIAL and MADV_RANDOM, it does not alter the - default readahead behavior. -2. Unlike MADV_SEQUENTIAL and MADV_RANDOM, it does not split VMAs and - therefore does not take mmap_lock. -3. Unlike MADV_COLD, setting it has a negligible cost, regardless of - how many pages it affects. - -Its limitations are: -1. Like POSIX_FADV_RANDOM and POSIX_FADV_SEQUENTIAL, it currently does - not support range. IOW, its scope is the entire file. -2. It currently does not ignore access through file descriptors. - Specifically, for the active/inactive LRU, given a file page shared - by two users and one of them having set POSIX_FADV_NOREUSE on the - file, this page will be activated upon the second user accessing - it. This corner case can be covered by checking POSIX_FADV_NOREUSE - before calling mark_page_accessed() on the read path. But it is - considered not worth the effort. - -There have been a few attempts to support POSIX_FADV_NOREUSE, e.g., [1]. -This time the goal is to fill a niche: a few desktop applications, e.g., -large file transferring and video encoding/decoding, want fast file -streaming with mmap() rather than direct IO. Among those applications, an -SVT-AV1 regression was reported when running with MGLRU [2]. The -following test can reproduce that regression. - - kb=$(awk '/MemTotal/ { print $2 }' /proc/meminfo) - kb=$((kb - 8*1024*1024)) - - modprobe brd rd_nr=1 rd_size=$kb - dd if=/dev/zero of=/dev/ram0 bs=1M - - mkfs.ext4 /dev/ram0 - mount /dev/ram0 /mnt/ - swapoff -a - - fallocate -l 8G /mnt/swapfile - mkswap /mnt/swapfile - swapon /mnt/swapfile - - wget http://ultravideo.cs.tut.fi/video/Bosphorus_3840x2160_120fps_420_8bit_YUV_Y4M.7z - 7z e -o/mnt/ Bosphorus_3840x2160_120fps_420_8bit_YUV_Y4M.7z - SvtAv1EncApp --preset 12 -w 3840 -h 2160 \ - -i /mnt/Bosphorus_3840x2160.y4m - -For MGLRU, the following change showed a [9-11]% increase in FPS, -which makes it on par with the active/inactive LRU. - - patch Source/App/EncApp/EbAppMain.c < #include - 35d35 - < #include /* _O_BINARY */ - 117a118 - > posix_fadvise(config->mmap.fd, 0, 0, POSIX_FADV_NOREUSE); - EOF - -[1] https://lore.kernel.org/r/1308923350-7932-1-git-send-email-andrea@betterlinux.com/ -[2] https://openbenchmarking.org/result/2209259-PTS-MGLRU8GB57 - -Link: https://lkml.kernel.org/r/20221230215252.2628425-2-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Alexander Viro -Cc: Andrea Righi -Cc: Johannes Weiner -Cc: Michael Larabel -Signed-off-by: Andrew Morton ---- - include/linux/fs.h | 2 ++ - include/linux/mm_inline.h | 3 +++ - mm/fadvise.c | 5 ++++- - 3 files changed, 9 insertions(+), 1 deletion(-) - ---- a/include/linux/fs.h -+++ b/include/linux/fs.h -@@ -166,6 +166,8 @@ typedef int (dio_iodone_t)(struct kiocb - /* File supports DIRECT IO */ - #define FMODE_CAN_ODIRECT ((__force fmode_t)0x400000) - -+#define FMODE_NOREUSE ((__force fmode_t)0x400000) -+ - /* File was opened by fanotify and shouldn't generate fanotify events */ - #define FMODE_NONOTIFY ((__force fmode_t)0x4000000) - ---- a/include/linux/mm_inline.h -+++ b/include/linux/mm_inline.h -@@ -583,6 +583,9 @@ static inline bool vma_has_recency(struc - if (vma->vm_flags & (VM_SEQ_READ | VM_RAND_READ)) - return false; - -+ if (vma->vm_file && (vma->vm_file->f_mode & FMODE_NOREUSE)) -+ return false; -+ - return true; - } - ---- a/mm/fadvise.c -+++ b/mm/fadvise.c -@@ -80,7 +80,7 @@ int generic_fadvise(struct file *file, l - case POSIX_FADV_NORMAL: - file->f_ra.ra_pages = bdi->ra_pages; - spin_lock(&file->f_lock); -- file->f_mode &= ~FMODE_RANDOM; -+ file->f_mode &= ~(FMODE_RANDOM | FMODE_NOREUSE); - spin_unlock(&file->f_lock); - break; - case POSIX_FADV_RANDOM: -@@ -107,6 +107,9 @@ int generic_fadvise(struct file *file, l - force_page_cache_readahead(mapping, file, start_index, nrpages); - break; - case POSIX_FADV_NOREUSE: -+ spin_lock(&file->f_lock); -+ file->f_mode |= FMODE_NOREUSE; -+ spin_unlock(&file->f_lock); - break; - case POSIX_FADV_DONTNEED: - __filemap_fdatawrite_range(mapping, offset, endbyte, diff --git a/target/linux/generic/backport-6.1/020-v6.3-21-mm-multi-gen-LRU-rename-lru_gen_struct-to-lru_gen_pa.patch b/target/linux/generic/backport-6.1/020-v6.3-21-mm-multi-gen-LRU-rename-lru_gen_struct-to-lru_gen_pa.patch deleted file mode 100644 index 881ef4e528..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-21-mm-multi-gen-LRU-rename-lru_gen_struct-to-lru_gen_pa.patch +++ /dev/null @@ -1,348 +0,0 @@ -From 348fdbada9fb3f0bf1a53651be46319105af187f Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Wed, 21 Dec 2022 21:18:59 -0700 -Subject: [PATCH 21/29] mm: multi-gen LRU: rename lru_gen_struct to - lru_gen_folio - -Patch series "mm: multi-gen LRU: memcg LRU", v3. - -Overview -======== - -An memcg LRU is a per-node LRU of memcgs. It is also an LRU of LRUs, -since each node and memcg combination has an LRU of folios (see -mem_cgroup_lruvec()). - -Its goal is to improve the scalability of global reclaim, which is -critical to system-wide memory overcommit in data centers. Note that -memcg reclaim is currently out of scope. - -Its memory bloat is a pointer to each lruvec and negligible to each -pglist_data. In terms of traversing memcgs during global reclaim, it -improves the best-case complexity from O(n) to O(1) and does not affect -the worst-case complexity O(n). Therefore, on average, it has a sublinear -complexity in contrast to the current linear complexity. - -The basic structure of an memcg LRU can be understood by an analogy to -the active/inactive LRU (of folios): -1. It has the young and the old (generations), i.e., the counterparts - to the active and the inactive; -2. The increment of max_seq triggers promotion, i.e., the counterpart - to activation; -3. Other events trigger similar operations, e.g., offlining an memcg - triggers demotion, i.e., the counterpart to deactivation. - -In terms of global reclaim, it has two distinct features: -1. Sharding, which allows each thread to start at a random memcg (in - the old generation) and improves parallelism; -2. Eventual fairness, which allows direct reclaim to bail out at will - and reduces latency without affecting fairness over some time. - -The commit message in patch 6 details the workflow: -https://lore.kernel.org/r/20221222041905.2431096-7-yuzhao@google.com/ - -The following is a simple test to quickly verify its effectiveness. - - Test design: - 1. Create multiple memcgs. - 2. Each memcg contains a job (fio). - 3. All jobs access the same amount of memory randomly. - 4. The system does not experience global memory pressure. - 5. Periodically write to the root memory.reclaim. - - Desired outcome: - 1. All memcgs have similar pgsteal counts, i.e., stddev(pgsteal) - over mean(pgsteal) is close to 0%. - 2. The total pgsteal is close to the total requested through - memory.reclaim, i.e., sum(pgsteal) over sum(requested) is close - to 100%. - - Actual outcome [1]: - MGLRU off MGLRU on - stddev(pgsteal) / mean(pgsteal) 75% 20% - sum(pgsteal) / sum(requested) 425% 95% - - #################################################################### - MEMCGS=128 - - for ((memcg = 0; memcg < $MEMCGS; memcg++)); do - mkdir /sys/fs/cgroup/memcg$memcg - done - - start() { - echo $BASHPID > /sys/fs/cgroup/memcg$memcg/cgroup.procs - - fio -name=memcg$memcg --numjobs=1 --ioengine=mmap \ - --filename=/dev/zero --size=1920M --rw=randrw \ - --rate=64m,64m --random_distribution=random \ - --fadvise_hint=0 --time_based --runtime=10h \ - --group_reporting --minimal - } - - for ((memcg = 0; memcg < $MEMCGS; memcg++)); do - start & - done - - sleep 600 - - for ((i = 0; i < 600; i++)); do - echo 256m >/sys/fs/cgroup/memory.reclaim - sleep 6 - done - - for ((memcg = 0; memcg < $MEMCGS; memcg++)); do - grep "pgsteal " /sys/fs/cgroup/memcg$memcg/memory.stat - done - #################################################################### - -[1]: This was obtained from running the above script (touches less - than 256GB memory) on an EPYC 7B13 with 512GB DRAM for over an - hour. - -This patch (of 8): - -The new name lru_gen_folio will be more distinct from the coming -lru_gen_memcg. - -Link: https://lkml.kernel.org/r/20221222041905.2431096-1-yuzhao@google.com -Link: https://lkml.kernel.org/r/20221222041905.2431096-2-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Johannes Weiner -Cc: Jonathan Corbet -Cc: Michael Larabel -Cc: Michal Hocko -Cc: Mike Rapoport -Cc: Roman Gushchin -Cc: Suren Baghdasaryan -Signed-off-by: Andrew Morton ---- - include/linux/mm_inline.h | 4 ++-- - include/linux/mmzone.h | 6 +++--- - mm/vmscan.c | 34 +++++++++++++++++----------------- - mm/workingset.c | 4 ++-- - 4 files changed, 24 insertions(+), 24 deletions(-) - ---- a/include/linux/mm_inline.h -+++ b/include/linux/mm_inline.h -@@ -178,7 +178,7 @@ static inline void lru_gen_update_size(s - int zone = folio_zonenum(folio); - int delta = folio_nr_pages(folio); - enum lru_list lru = type * LRU_INACTIVE_FILE; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - - VM_WARN_ON_ONCE(old_gen != -1 && old_gen >= MAX_NR_GENS); - VM_WARN_ON_ONCE(new_gen != -1 && new_gen >= MAX_NR_GENS); -@@ -224,7 +224,7 @@ static inline bool lru_gen_add_folio(str - int gen = folio_lru_gen(folio); - int type = folio_is_file_lru(folio); - int zone = folio_zonenum(folio); -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - - VM_WARN_ON_ONCE_FOLIO(gen != -1, folio); - ---- a/include/linux/mmzone.h -+++ b/include/linux/mmzone.h -@@ -404,7 +404,7 @@ enum { - * The number of pages in each generation is eventually consistent and therefore - * can be transiently negative when reset_batch_size() is pending. - */ --struct lru_gen_struct { -+struct lru_gen_folio { - /* the aging increments the youngest generation number */ - unsigned long max_seq; - /* the eviction increments the oldest generation numbers */ -@@ -461,7 +461,7 @@ struct lru_gen_mm_state { - struct lru_gen_mm_walk { - /* the lruvec under reclaim */ - struct lruvec *lruvec; -- /* unstable max_seq from lru_gen_struct */ -+ /* unstable max_seq from lru_gen_folio */ - unsigned long max_seq; - /* the next address within an mm to scan */ - unsigned long next_addr; -@@ -524,7 +524,7 @@ struct lruvec { - unsigned long flags; - #ifdef CONFIG_LRU_GEN - /* evictable pages divided into generations */ -- struct lru_gen_struct lrugen; -+ struct lru_gen_folio lrugen; - /* to concurrently iterate lru_gen_mm_list */ - struct lru_gen_mm_state mm_state; - #endif ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -3190,7 +3190,7 @@ static int get_nr_gens(struct lruvec *lr - - static bool __maybe_unused seq_is_valid(struct lruvec *lruvec) - { -- /* see the comment on lru_gen_struct */ -+ /* see the comment on lru_gen_folio */ - return get_nr_gens(lruvec, LRU_GEN_FILE) >= MIN_NR_GENS && - get_nr_gens(lruvec, LRU_GEN_FILE) <= get_nr_gens(lruvec, LRU_GEN_ANON) && - get_nr_gens(lruvec, LRU_GEN_ANON) <= MAX_NR_GENS; -@@ -3596,7 +3596,7 @@ struct ctrl_pos { - static void read_ctrl_pos(struct lruvec *lruvec, int type, int tier, int gain, - struct ctrl_pos *pos) - { -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - int hist = lru_hist_from_seq(lrugen->min_seq[type]); - - pos->refaulted = lrugen->avg_refaulted[type][tier] + -@@ -3611,7 +3611,7 @@ static void read_ctrl_pos(struct lruvec - static void reset_ctrl_pos(struct lruvec *lruvec, int type, bool carryover) - { - int hist, tier; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - bool clear = carryover ? NR_HIST_GENS == 1 : NR_HIST_GENS > 1; - unsigned long seq = carryover ? lrugen->min_seq[type] : lrugen->max_seq + 1; - -@@ -3688,7 +3688,7 @@ static int folio_update_gen(struct folio - static int folio_inc_gen(struct lruvec *lruvec, struct folio *folio, bool reclaiming) - { - int type = folio_is_file_lru(folio); -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - int new_gen, old_gen = lru_gen_from_seq(lrugen->min_seq[type]); - unsigned long new_flags, old_flags = READ_ONCE(folio->flags); - -@@ -3733,7 +3733,7 @@ static void update_batch_size(struct lru - static void reset_batch_size(struct lruvec *lruvec, struct lru_gen_mm_walk *walk) - { - int gen, type, zone; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - - walk->batched = 0; - -@@ -4253,7 +4253,7 @@ static bool inc_min_seq(struct lruvec *l - { - int zone; - int remaining = MAX_LRU_BATCH; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - int new_gen, old_gen = lru_gen_from_seq(lrugen->min_seq[type]); - - if (type == LRU_GEN_ANON && !can_swap) -@@ -4289,7 +4289,7 @@ static bool try_to_inc_min_seq(struct lr - { - int gen, type, zone; - bool success = false; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - DEFINE_MIN_SEQ(lruvec); - - VM_WARN_ON_ONCE(!seq_is_valid(lruvec)); -@@ -4310,7 +4310,7 @@ next: - ; - } - -- /* see the comment on lru_gen_struct */ -+ /* see the comment on lru_gen_folio */ - if (can_swap) { - min_seq[LRU_GEN_ANON] = min(min_seq[LRU_GEN_ANON], min_seq[LRU_GEN_FILE]); - min_seq[LRU_GEN_FILE] = max(min_seq[LRU_GEN_ANON], lrugen->min_seq[LRU_GEN_FILE]); -@@ -4332,7 +4332,7 @@ static void inc_max_seq(struct lruvec *l - { - int prev, next; - int type, zone; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - - spin_lock_irq(&lruvec->lru_lock); - -@@ -4390,7 +4390,7 @@ static bool try_to_inc_max_seq(struct lr - bool success; - struct lru_gen_mm_walk *walk; - struct mm_struct *mm = NULL; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - - VM_WARN_ON_ONCE(max_seq > READ_ONCE(lrugen->max_seq)); - -@@ -4455,7 +4455,7 @@ static bool should_run_aging(struct lruv - unsigned long old = 0; - unsigned long young = 0; - unsigned long total = 0; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - struct mem_cgroup *memcg = lruvec_memcg(lruvec); - - for (type = !can_swap; type < ANON_AND_FILE; type++) { -@@ -4740,7 +4740,7 @@ static bool sort_folio(struct lruvec *lr - int delta = folio_nr_pages(folio); - int refs = folio_lru_refs(folio); - int tier = lru_tier_from_refs(refs); -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - - VM_WARN_ON_ONCE_FOLIO(gen >= MAX_NR_GENS, folio); - -@@ -4840,7 +4840,7 @@ static int scan_folios(struct lruvec *lr - int scanned = 0; - int isolated = 0; - int remaining = MAX_LRU_BATCH; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - struct mem_cgroup *memcg = lruvec_memcg(lruvec); - - VM_WARN_ON_ONCE(!list_empty(list)); -@@ -5240,7 +5240,7 @@ done: - - static bool __maybe_unused state_is_valid(struct lruvec *lruvec) - { -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - - if (lrugen->enabled) { - enum lru_list lru; -@@ -5522,7 +5522,7 @@ static void lru_gen_seq_show_full(struct - int i; - int type, tier; - int hist = lru_hist_from_seq(seq); -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - - for (tier = 0; tier < MAX_NR_TIERS; tier++) { - seq_printf(m, " %10d", tier); -@@ -5572,7 +5572,7 @@ static int lru_gen_seq_show(struct seq_f - unsigned long seq; - bool full = !debugfs_real_fops(m->file)->write; - struct lruvec *lruvec = v; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - int nid = lruvec_pgdat(lruvec)->node_id; - struct mem_cgroup *memcg = lruvec_memcg(lruvec); - DEFINE_MAX_SEQ(lruvec); -@@ -5826,7 +5826,7 @@ void lru_gen_init_lruvec(struct lruvec * - { - int i; - int gen, type, zone; -- struct lru_gen_struct *lrugen = &lruvec->lrugen; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - - lrugen->max_seq = MIN_NR_GENS + 1; - lrugen->enabled = lru_gen_enabled(); ---- a/mm/workingset.c -+++ b/mm/workingset.c -@@ -223,7 +223,7 @@ static void *lru_gen_eviction(struct fol - unsigned long token; - unsigned long min_seq; - struct lruvec *lruvec; -- struct lru_gen_struct *lrugen; -+ struct lru_gen_folio *lrugen; - int type = folio_is_file_lru(folio); - int delta = folio_nr_pages(folio); - int refs = folio_lru_refs(folio); -@@ -252,7 +252,7 @@ static void lru_gen_refault(struct folio - unsigned long token; - unsigned long min_seq; - struct lruvec *lruvec; -- struct lru_gen_struct *lrugen; -+ struct lru_gen_folio *lrugen; - struct mem_cgroup *memcg; - struct pglist_data *pgdat; - int type = folio_is_file_lru(folio); diff --git a/target/linux/generic/backport-6.1/020-v6.3-22-mm-multi-gen-LRU-rename-lrugen-lists-to-lrugen-pages.patch b/target/linux/generic/backport-6.1/020-v6.3-22-mm-multi-gen-LRU-rename-lrugen-lists-to-lrugen-pages.patch deleted file mode 100644 index 7940380c5c..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-22-mm-multi-gen-LRU-rename-lrugen-lists-to-lrugen-pages.patch +++ /dev/null @@ -1,162 +0,0 @@ -From afd37e73db04c7e6b47411120ac5f6a7eca51fec Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Wed, 21 Dec 2022 21:19:00 -0700 -Subject: [PATCH 22/29] mm: multi-gen LRU: rename lrugen->lists[] to - lrugen->folios[] - -lru_gen_folio will be chained into per-node lists by the coming -lrugen->list. - -Link: https://lkml.kernel.org/r/20221222041905.2431096-3-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Johannes Weiner -Cc: Jonathan Corbet -Cc: Michael Larabel -Cc: Michal Hocko -Cc: Mike Rapoport -Cc: Roman Gushchin -Cc: Suren Baghdasaryan -Signed-off-by: Andrew Morton ---- - include/linux/mm_inline.h | 4 ++-- - include/linux/mmzone.h | 8 ++++---- - mm/vmscan.c | 20 ++++++++++---------- - 3 files changed, 16 insertions(+), 16 deletions(-) - ---- a/include/linux/mm_inline.h -+++ b/include/linux/mm_inline.h -@@ -256,9 +256,9 @@ static inline bool lru_gen_add_folio(str - lru_gen_update_size(lruvec, folio, -1, gen); - /* for folio_rotate_reclaimable() */ - if (reclaiming) -- list_add_tail(&folio->lru, &lrugen->lists[gen][type][zone]); -+ list_add_tail(&folio->lru, &lrugen->folios[gen][type][zone]); - else -- list_add(&folio->lru, &lrugen->lists[gen][type][zone]); -+ list_add(&folio->lru, &lrugen->folios[gen][type][zone]); - - return true; - } ---- a/include/linux/mmzone.h -+++ b/include/linux/mmzone.h -@@ -312,7 +312,7 @@ enum lruvec_flags { - * They form a sliding window of a variable size [MIN_NR_GENS, MAX_NR_GENS]. An - * offset within MAX_NR_GENS, i.e., gen, indexes the LRU list of the - * corresponding generation. The gen counter in folio->flags stores gen+1 while -- * a page is on one of lrugen->lists[]. Otherwise it stores 0. -+ * a page is on one of lrugen->folios[]. Otherwise it stores 0. - * - * A page is added to the youngest generation on faulting. The aging needs to - * check the accessed bit at least twice before handing this page over to the -@@ -324,8 +324,8 @@ enum lruvec_flags { - * rest of generations, if they exist, are considered inactive. See - * lru_gen_is_active(). - * -- * PG_active is always cleared while a page is on one of lrugen->lists[] so that -- * the aging needs not to worry about it. And it's set again when a page -+ * PG_active is always cleared while a page is on one of lrugen->folios[] so -+ * that the aging needs not to worry about it. And it's set again when a page - * considered active is isolated for non-reclaiming purposes, e.g., migration. - * See lru_gen_add_folio() and lru_gen_del_folio(). - * -@@ -412,7 +412,7 @@ struct lru_gen_folio { - /* the birth time of each generation in jiffies */ - unsigned long timestamps[MAX_NR_GENS]; - /* the multi-gen LRU lists, lazily sorted on eviction */ -- struct list_head lists[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; -+ struct list_head folios[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; - /* the multi-gen LRU sizes, eventually consistent */ - long nr_pages[MAX_NR_GENS][ANON_AND_FILE][MAX_NR_ZONES]; - /* the exponential moving average of refaulted */ ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -4261,7 +4261,7 @@ static bool inc_min_seq(struct lruvec *l - - /* prevent cold/hot inversion if force_scan is true */ - for (zone = 0; zone < MAX_NR_ZONES; zone++) { -- struct list_head *head = &lrugen->lists[old_gen][type][zone]; -+ struct list_head *head = &lrugen->folios[old_gen][type][zone]; - - while (!list_empty(head)) { - struct folio *folio = lru_to_folio(head); -@@ -4272,7 +4272,7 @@ static bool inc_min_seq(struct lruvec *l - VM_WARN_ON_ONCE_FOLIO(folio_zonenum(folio) != zone, folio); - - new_gen = folio_inc_gen(lruvec, folio, false); -- list_move_tail(&folio->lru, &lrugen->lists[new_gen][type][zone]); -+ list_move_tail(&folio->lru, &lrugen->folios[new_gen][type][zone]); - - if (!--remaining) - return false; -@@ -4300,7 +4300,7 @@ static bool try_to_inc_min_seq(struct lr - gen = lru_gen_from_seq(min_seq[type]); - - for (zone = 0; zone < MAX_NR_ZONES; zone++) { -- if (!list_empty(&lrugen->lists[gen][type][zone])) -+ if (!list_empty(&lrugen->folios[gen][type][zone])) - goto next; - } - -@@ -4765,7 +4765,7 @@ static bool sort_folio(struct lruvec *lr - - /* promoted */ - if (gen != lru_gen_from_seq(lrugen->min_seq[type])) { -- list_move(&folio->lru, &lrugen->lists[gen][type][zone]); -+ list_move(&folio->lru, &lrugen->folios[gen][type][zone]); - return true; - } - -@@ -4774,7 +4774,7 @@ static bool sort_folio(struct lruvec *lr - int hist = lru_hist_from_seq(lrugen->min_seq[type]); - - gen = folio_inc_gen(lruvec, folio, false); -- list_move_tail(&folio->lru, &lrugen->lists[gen][type][zone]); -+ list_move_tail(&folio->lru, &lrugen->folios[gen][type][zone]); - - WRITE_ONCE(lrugen->protected[hist][type][tier - 1], - lrugen->protected[hist][type][tier - 1] + delta); -@@ -4786,7 +4786,7 @@ static bool sort_folio(struct lruvec *lr - if (folio_test_locked(folio) || folio_test_writeback(folio) || - (type == LRU_GEN_FILE && folio_test_dirty(folio))) { - gen = folio_inc_gen(lruvec, folio, true); -- list_move(&folio->lru, &lrugen->lists[gen][type][zone]); -+ list_move(&folio->lru, &lrugen->folios[gen][type][zone]); - return true; - } - -@@ -4853,7 +4853,7 @@ static int scan_folios(struct lruvec *lr - for (zone = sc->reclaim_idx; zone >= 0; zone--) { - LIST_HEAD(moved); - int skipped = 0; -- struct list_head *head = &lrugen->lists[gen][type][zone]; -+ struct list_head *head = &lrugen->folios[gen][type][zone]; - - while (!list_empty(head)) { - struct folio *folio = lru_to_folio(head); -@@ -5253,7 +5253,7 @@ static bool __maybe_unused state_is_vali - int gen, type, zone; - - for_each_gen_type_zone(gen, type, zone) { -- if (!list_empty(&lrugen->lists[gen][type][zone])) -+ if (!list_empty(&lrugen->folios[gen][type][zone])) - return false; - } - } -@@ -5298,7 +5298,7 @@ static bool drain_evictable(struct lruve - int remaining = MAX_LRU_BATCH; - - for_each_gen_type_zone(gen, type, zone) { -- struct list_head *head = &lruvec->lrugen.lists[gen][type][zone]; -+ struct list_head *head = &lruvec->lrugen.folios[gen][type][zone]; - - while (!list_empty(head)) { - bool success; -@@ -5835,7 +5835,7 @@ void lru_gen_init_lruvec(struct lruvec * - lrugen->timestamps[i] = jiffies; - - for_each_gen_type_zone(gen, type, zone) -- INIT_LIST_HEAD(&lrugen->lists[gen][type][zone]); -+ INIT_LIST_HEAD(&lrugen->folios[gen][type][zone]); - - lruvec->mm_state.seq = MIN_NR_GENS; - init_waitqueue_head(&lruvec->mm_state.wait); diff --git a/target/linux/generic/backport-6.1/020-v6.3-23-mm-multi-gen-LRU-remove-eviction-fairness-safeguard.patch b/target/linux/generic/backport-6.1/020-v6.3-23-mm-multi-gen-LRU-remove-eviction-fairness-safeguard.patch deleted file mode 100644 index d214898a6d..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-23-mm-multi-gen-LRU-remove-eviction-fairness-safeguard.patch +++ /dev/null @@ -1,187 +0,0 @@ -From ce45f1c4b32cf69b166f56ef5bc6c761e06ed4e5 Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Wed, 21 Dec 2022 21:19:01 -0700 -Subject: [PATCH 23/29] mm: multi-gen LRU: remove eviction fairness safeguard - -Recall that the eviction consumes the oldest generation: first it -bucket-sorts folios whose gen counters were updated by the aging and -reclaims the rest; then it increments lrugen->min_seq. - -The current eviction fairness safeguard for global reclaim has a -dilemma: when there are multiple eligible memcgs, should it continue -or stop upon meeting the reclaim goal? If it continues, it overshoots -and increases direct reclaim latency; if it stops, it loses fairness -between memcgs it has taken memory away from and those it has yet to. - -With memcg LRU, the eviction, while ensuring eventual fairness, will -stop upon meeting its goal. Therefore the current eviction fairness -safeguard for global reclaim will not be needed. - -Note that memcg LRU only applies to global reclaim. For memcg reclaim, -the eviction will continue, even if it is overshooting. This becomes -unconditional due to code simplification. - -Link: https://lkml.kernel.org/r/20221222041905.2431096-4-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Johannes Weiner -Cc: Jonathan Corbet -Cc: Michael Larabel -Cc: Michal Hocko -Cc: Mike Rapoport -Cc: Roman Gushchin -Cc: Suren Baghdasaryan -Signed-off-by: Andrew Morton ---- - mm/vmscan.c | 82 +++++++++++++++-------------------------------------- - 1 file changed, 23 insertions(+), 59 deletions(-) - ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -448,6 +448,11 @@ static bool cgroup_reclaim(struct scan_c - return sc->target_mem_cgroup; - } - -+static bool global_reclaim(struct scan_control *sc) -+{ -+ return !sc->target_mem_cgroup || mem_cgroup_is_root(sc->target_mem_cgroup); -+} -+ - /** - * writeback_throttling_sane - is the usual dirty throttling mechanism available? - * @sc: scan_control in question -@@ -498,6 +503,11 @@ static bool cgroup_reclaim(struct scan_c - return false; - } - -+static bool global_reclaim(struct scan_control *sc) -+{ -+ return true; -+} -+ - static bool writeback_throttling_sane(struct scan_control *sc) - { - return true; -@@ -4996,8 +5006,7 @@ static int isolate_folios(struct lruvec - return scanned; - } - --static int evict_folios(struct lruvec *lruvec, struct scan_control *sc, int swappiness, -- bool *need_swapping) -+static int evict_folios(struct lruvec *lruvec, struct scan_control *sc, int swappiness) - { - int type; - int scanned; -@@ -5086,9 +5095,6 @@ retry: - goto retry; - } - -- if (need_swapping && type == LRU_GEN_ANON) -- *need_swapping = true; -- - return scanned; - } - -@@ -5127,67 +5133,26 @@ done: - return min_seq[!can_swap] + MIN_NR_GENS <= max_seq ? nr_to_scan : 0; - } - --static bool should_abort_scan(struct lruvec *lruvec, unsigned long seq, -- struct scan_control *sc, bool need_swapping) -+static unsigned long get_nr_to_reclaim(struct scan_control *sc) - { -- int i; -- DEFINE_MAX_SEQ(lruvec); -- -- if (!current_is_kswapd()) { -- /* age each memcg at most once to ensure fairness */ -- if (max_seq - seq > 1) -- return true; -- -- /* over-swapping can increase allocation latency */ -- if (sc->nr_reclaimed >= sc->nr_to_reclaim && need_swapping) -- return true; -- -- /* give this thread a chance to exit and free its memory */ -- if (fatal_signal_pending(current)) { -- sc->nr_reclaimed += MIN_LRU_BATCH; -- return true; -- } -- -- if (cgroup_reclaim(sc)) -- return false; -- } else if (sc->nr_reclaimed - sc->last_reclaimed < sc->nr_to_reclaim) -- return false; -- -- /* keep scanning at low priorities to ensure fairness */ -- if (sc->priority > DEF_PRIORITY - 2) -- return false; -- -- /* -- * A minimum amount of work was done under global memory pressure. For -- * kswapd, it may be overshooting. For direct reclaim, the allocation -- * may succeed if all suitable zones are somewhat safe. In either case, -- * it's better to stop now, and restart later if necessary. -- */ -- for (i = 0; i <= sc->reclaim_idx; i++) { -- unsigned long wmark; -- struct zone *zone = lruvec_pgdat(lruvec)->node_zones + i; -- -- if (!managed_zone(zone)) -- continue; -- -- wmark = current_is_kswapd() ? high_wmark_pages(zone) : low_wmark_pages(zone); -- if (wmark > zone_page_state(zone, NR_FREE_PAGES)) -- return false; -- } -+ /* don't abort memcg reclaim to ensure fairness */ -+ if (!global_reclaim(sc)) -+ return -1; - -- sc->nr_reclaimed += MIN_LRU_BATCH; -+ /* discount the previous progress for kswapd */ -+ if (current_is_kswapd()) -+ return sc->nr_to_reclaim + sc->last_reclaimed; - -- return true; -+ return max(sc->nr_to_reclaim, compact_gap(sc->order)); - } - - static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) - { - struct blk_plug plug; - bool need_aging = false; -- bool need_swapping = false; - unsigned long scanned = 0; - unsigned long reclaimed = sc->nr_reclaimed; -- DEFINE_MAX_SEQ(lruvec); -+ unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); - - lru_add_drain(); - -@@ -5211,7 +5176,7 @@ static void lru_gen_shrink_lruvec(struct - if (!nr_to_scan) - goto done; - -- delta = evict_folios(lruvec, sc, swappiness, &need_swapping); -+ delta = evict_folios(lruvec, sc, swappiness); - if (!delta) - goto done; - -@@ -5219,7 +5184,7 @@ static void lru_gen_shrink_lruvec(struct - if (scanned >= nr_to_scan) - break; - -- if (should_abort_scan(lruvec, max_seq, sc, need_swapping)) -+ if (sc->nr_reclaimed >= nr_to_reclaim) - break; - - cond_resched(); -@@ -5669,7 +5634,7 @@ static int run_eviction(struct lruvec *l - if (sc->nr_reclaimed >= nr_to_reclaim) - return 0; - -- if (!evict_folios(lruvec, sc, swappiness, NULL)) -+ if (!evict_folios(lruvec, sc, swappiness)) - return 0; - - cond_resched(); diff --git a/target/linux/generic/backport-6.1/020-v6.3-24-mm-multi-gen-LRU-remove-aging-fairness-safeguard.patch b/target/linux/generic/backport-6.1/020-v6.3-24-mm-multi-gen-LRU-remove-aging-fairness-safeguard.patch deleted file mode 100644 index 7cbabd34e4..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-24-mm-multi-gen-LRU-remove-aging-fairness-safeguard.patch +++ /dev/null @@ -1,287 +0,0 @@ -From e20b7386fccc18c791796eb1dc1a91eee3ccf801 Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Wed, 21 Dec 2022 21:19:02 -0700 -Subject: [PATCH 24/29] mm: multi-gen LRU: remove aging fairness safeguard - -Recall that the aging produces the youngest generation: first it scans -for accessed folios and updates their gen counters; then it increments -lrugen->max_seq. - -The current aging fairness safeguard for kswapd uses two passes to -ensure the fairness to multiple eligible memcgs. On the first pass, -which is shared with the eviction, it checks whether all eligible -memcgs are low on cold folios. If so, it requires a second pass, on -which it ages all those memcgs at the same time. - -With memcg LRU, the aging, while ensuring eventual fairness, will run -when necessary. Therefore the current aging fairness safeguard for -kswapd will not be needed. - -Note that memcg LRU only applies to global reclaim. For memcg reclaim, -the aging can be unfair to different memcgs, i.e., their -lrugen->max_seq can be incremented at different paces. - -Link: https://lkml.kernel.org/r/20221222041905.2431096-5-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Johannes Weiner -Cc: Jonathan Corbet -Cc: Michael Larabel -Cc: Michal Hocko -Cc: Mike Rapoport -Cc: Roman Gushchin -Cc: Suren Baghdasaryan -Signed-off-by: Andrew Morton ---- - mm/vmscan.c | 126 ++++++++++++++++++++++++---------------------------- - 1 file changed, 59 insertions(+), 67 deletions(-) - ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -136,7 +136,6 @@ struct scan_control { - - #ifdef CONFIG_LRU_GEN - /* help kswapd make better choices among multiple memcgs */ -- unsigned int memcgs_need_aging:1; - unsigned long last_reclaimed; - #endif - -@@ -4458,7 +4457,7 @@ done: - return true; - } - --static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, unsigned long *min_seq, -+static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, - struct scan_control *sc, bool can_swap, unsigned long *nr_to_scan) - { - int gen, type, zone; -@@ -4467,6 +4466,13 @@ static bool should_run_aging(struct lruv - unsigned long total = 0; - struct lru_gen_folio *lrugen = &lruvec->lrugen; - struct mem_cgroup *memcg = lruvec_memcg(lruvec); -+ DEFINE_MIN_SEQ(lruvec); -+ -+ /* whether this lruvec is completely out of cold folios */ -+ if (min_seq[!can_swap] + MIN_NR_GENS > max_seq) { -+ *nr_to_scan = 0; -+ return true; -+ } - - for (type = !can_swap; type < ANON_AND_FILE; type++) { - unsigned long seq; -@@ -4495,8 +4501,6 @@ static bool should_run_aging(struct lruv - * stalls when the number of generations reaches MIN_NR_GENS. Hence, the - * ideal number of generations is MIN_NR_GENS+1. - */ -- if (min_seq[!can_swap] + MIN_NR_GENS > max_seq) -- return true; - if (min_seq[!can_swap] + MIN_NR_GENS < max_seq) - return false; - -@@ -4515,40 +4519,54 @@ static bool should_run_aging(struct lruv - return false; - } - --static bool age_lruvec(struct lruvec *lruvec, struct scan_control *sc, unsigned long min_ttl) -+static bool lruvec_is_sizable(struct lruvec *lruvec, struct scan_control *sc) - { -- bool need_aging; -- unsigned long nr_to_scan; -- int swappiness = get_swappiness(lruvec, sc); -+ int gen, type, zone; -+ unsigned long total = 0; -+ bool can_swap = get_swappiness(lruvec, sc); -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; - struct mem_cgroup *memcg = lruvec_memcg(lruvec); - DEFINE_MAX_SEQ(lruvec); - DEFINE_MIN_SEQ(lruvec); - -- VM_WARN_ON_ONCE(sc->memcg_low_reclaim); -+ for (type = !can_swap; type < ANON_AND_FILE; type++) { -+ unsigned long seq; - -- mem_cgroup_calculate_protection(NULL, memcg); -+ for (seq = min_seq[type]; seq <= max_seq; seq++) { -+ gen = lru_gen_from_seq(seq); - -- if (mem_cgroup_below_min(memcg)) -- return false; -+ for (zone = 0; zone < MAX_NR_ZONES; zone++) -+ total += max(READ_ONCE(lrugen->nr_pages[gen][type][zone]), 0L); -+ } -+ } - -- need_aging = should_run_aging(lruvec, max_seq, min_seq, sc, swappiness, &nr_to_scan); -+ /* whether the size is big enough to be helpful */ -+ return mem_cgroup_online(memcg) ? (total >> sc->priority) : total; -+} - -- if (min_ttl) { -- int gen = lru_gen_from_seq(min_seq[LRU_GEN_FILE]); -- unsigned long birth = READ_ONCE(lruvec->lrugen.timestamps[gen]); -+static bool lruvec_is_reclaimable(struct lruvec *lruvec, struct scan_control *sc, -+ unsigned long min_ttl) -+{ -+ int gen; -+ unsigned long birth; -+ struct mem_cgroup *memcg = lruvec_memcg(lruvec); -+ DEFINE_MIN_SEQ(lruvec); - -- if (time_is_after_jiffies(birth + min_ttl)) -- return false; -+ VM_WARN_ON_ONCE(sc->memcg_low_reclaim); - -- /* the size is likely too small to be helpful */ -- if (!nr_to_scan && sc->priority != DEF_PRIORITY) -- return false; -- } -+ /* see the comment on lru_gen_folio */ -+ gen = lru_gen_from_seq(min_seq[LRU_GEN_FILE]); -+ birth = READ_ONCE(lruvec->lrugen.timestamps[gen]); - -- if (need_aging) -- try_to_inc_max_seq(lruvec, max_seq, sc, swappiness, false); -+ if (time_is_after_jiffies(birth + min_ttl)) -+ return false; - -- return true; -+ if (!lruvec_is_sizable(lruvec, sc)) -+ return false; -+ -+ mem_cgroup_calculate_protection(NULL, memcg); -+ -+ return !mem_cgroup_below_min(memcg); - } - - /* to protect the working set of the last N jiffies */ -@@ -4557,46 +4575,32 @@ static unsigned long lru_gen_min_ttl __r - static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc) - { - struct mem_cgroup *memcg; -- bool success = false; - unsigned long min_ttl = READ_ONCE(lru_gen_min_ttl); - - VM_WARN_ON_ONCE(!current_is_kswapd()); - - sc->last_reclaimed = sc->nr_reclaimed; - -- /* -- * To reduce the chance of going into the aging path, which can be -- * costly, optimistically skip it if the flag below was cleared in the -- * eviction path. This improves the overall performance when multiple -- * memcgs are available. -- */ -- if (!sc->memcgs_need_aging) { -- sc->memcgs_need_aging = true; -+ /* check the order to exclude compaction-induced reclaim */ -+ if (!min_ttl || sc->order || sc->priority == DEF_PRIORITY) - return; -- } -- -- set_mm_walk(pgdat); - - memcg = mem_cgroup_iter(NULL, NULL, NULL); - do { - struct lruvec *lruvec = mem_cgroup_lruvec(memcg, pgdat); - -- if (age_lruvec(lruvec, sc, min_ttl)) -- success = true; -+ if (lruvec_is_reclaimable(lruvec, sc, min_ttl)) { -+ mem_cgroup_iter_break(NULL, memcg); -+ return; -+ } - - cond_resched(); - } while ((memcg = mem_cgroup_iter(NULL, memcg, NULL))); - -- clear_mm_walk(); -- -- /* check the order to exclude compaction-induced reclaim */ -- if (success || !min_ttl || sc->order) -- return; -- - /* - * The main goal is to OOM kill if every generation from all memcgs is - * younger than min_ttl. However, another possibility is all memcgs are -- * either below min or empty. -+ * either too small or below min. - */ - if (mutex_trylock(&oom_lock)) { - struct oom_control oc = { -@@ -5104,33 +5108,27 @@ retry: - * reclaim. - */ - static unsigned long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, -- bool can_swap, bool *need_aging) -+ bool can_swap) - { - unsigned long nr_to_scan; - struct mem_cgroup *memcg = lruvec_memcg(lruvec); - DEFINE_MAX_SEQ(lruvec); -- DEFINE_MIN_SEQ(lruvec); - - if (mem_cgroup_below_min(memcg) || - (mem_cgroup_below_low(memcg) && !sc->memcg_low_reclaim)) - return 0; - -- *need_aging = should_run_aging(lruvec, max_seq, min_seq, sc, can_swap, &nr_to_scan); -- if (!*need_aging) -+ if (!should_run_aging(lruvec, max_seq, sc, can_swap, &nr_to_scan)) - return nr_to_scan; - - /* skip the aging path at the default priority */ - if (sc->priority == DEF_PRIORITY) -- goto done; -+ return nr_to_scan; - -- /* leave the work to lru_gen_age_node() */ -- if (current_is_kswapd()) -- return 0; -+ try_to_inc_max_seq(lruvec, max_seq, sc, can_swap, false); - -- if (try_to_inc_max_seq(lruvec, max_seq, sc, can_swap, false)) -- return nr_to_scan; --done: -- return min_seq[!can_swap] + MIN_NR_GENS <= max_seq ? nr_to_scan : 0; -+ /* skip this lruvec as it's low on cold folios */ -+ return 0; - } - - static unsigned long get_nr_to_reclaim(struct scan_control *sc) -@@ -5149,9 +5147,7 @@ static unsigned long get_nr_to_reclaim(s - static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) - { - struct blk_plug plug; -- bool need_aging = false; - unsigned long scanned = 0; -- unsigned long reclaimed = sc->nr_reclaimed; - unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); - - lru_add_drain(); -@@ -5172,13 +5168,13 @@ static void lru_gen_shrink_lruvec(struct - else - swappiness = 0; - -- nr_to_scan = get_nr_to_scan(lruvec, sc, swappiness, &need_aging); -+ nr_to_scan = get_nr_to_scan(lruvec, sc, swappiness); - if (!nr_to_scan) -- goto done; -+ break; - - delta = evict_folios(lruvec, sc, swappiness); - if (!delta) -- goto done; -+ break; - - scanned += delta; - if (scanned >= nr_to_scan) -@@ -5190,10 +5186,6 @@ static void lru_gen_shrink_lruvec(struct - cond_resched(); - } - -- /* see the comment in lru_gen_age_node() */ -- if (sc->nr_reclaimed - reclaimed >= MIN_LRU_BATCH && !need_aging) -- sc->memcgs_need_aging = false; --done: - clear_mm_walk(); - - blk_finish_plug(&plug); diff --git a/target/linux/generic/backport-6.1/020-v6.3-25-mm-multi-gen-LRU-shuffle-should_run_aging.patch b/target/linux/generic/backport-6.1/020-v6.3-25-mm-multi-gen-LRU-shuffle-should_run_aging.patch deleted file mode 100644 index bedbbd3e1b..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-25-mm-multi-gen-LRU-shuffle-should_run_aging.patch +++ /dev/null @@ -1,161 +0,0 @@ -From 107d54931df3c28d81648122e219bf0034ef4e99 Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Wed, 21 Dec 2022 21:19:03 -0700 -Subject: [PATCH 25/29] mm: multi-gen LRU: shuffle should_run_aging() - -Move should_run_aging() next to its only caller left. - -Link: https://lkml.kernel.org/r/20221222041905.2431096-6-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Johannes Weiner -Cc: Jonathan Corbet -Cc: Michael Larabel -Cc: Michal Hocko -Cc: Mike Rapoport -Cc: Roman Gushchin -Cc: Suren Baghdasaryan -Signed-off-by: Andrew Morton ---- - mm/vmscan.c | 124 ++++++++++++++++++++++++++-------------------------- - 1 file changed, 62 insertions(+), 62 deletions(-) - ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -4457,68 +4457,6 @@ done: - return true; - } - --static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, -- struct scan_control *sc, bool can_swap, unsigned long *nr_to_scan) --{ -- int gen, type, zone; -- unsigned long old = 0; -- unsigned long young = 0; -- unsigned long total = 0; -- struct lru_gen_folio *lrugen = &lruvec->lrugen; -- struct mem_cgroup *memcg = lruvec_memcg(lruvec); -- DEFINE_MIN_SEQ(lruvec); -- -- /* whether this lruvec is completely out of cold folios */ -- if (min_seq[!can_swap] + MIN_NR_GENS > max_seq) { -- *nr_to_scan = 0; -- return true; -- } -- -- for (type = !can_swap; type < ANON_AND_FILE; type++) { -- unsigned long seq; -- -- for (seq = min_seq[type]; seq <= max_seq; seq++) { -- unsigned long size = 0; -- -- gen = lru_gen_from_seq(seq); -- -- for (zone = 0; zone < MAX_NR_ZONES; zone++) -- size += max(READ_ONCE(lrugen->nr_pages[gen][type][zone]), 0L); -- -- total += size; -- if (seq == max_seq) -- young += size; -- else if (seq + MIN_NR_GENS == max_seq) -- old += size; -- } -- } -- -- /* try to scrape all its memory if this memcg was deleted */ -- *nr_to_scan = mem_cgroup_online(memcg) ? (total >> sc->priority) : total; -- -- /* -- * The aging tries to be lazy to reduce the overhead, while the eviction -- * stalls when the number of generations reaches MIN_NR_GENS. Hence, the -- * ideal number of generations is MIN_NR_GENS+1. -- */ -- if (min_seq[!can_swap] + MIN_NR_GENS < max_seq) -- return false; -- -- /* -- * It's also ideal to spread pages out evenly, i.e., 1/(MIN_NR_GENS+1) -- * of the total number of pages for each generation. A reasonable range -- * for this average portion is [1/MIN_NR_GENS, 1/(MIN_NR_GENS+2)]. The -- * aging cares about the upper bound of hot pages, while the eviction -- * cares about the lower bound of cold pages. -- */ -- if (young * MIN_NR_GENS > total) -- return true; -- if (old * (MIN_NR_GENS + 2) < total) -- return true; -- -- return false; --} -- - static bool lruvec_is_sizable(struct lruvec *lruvec, struct scan_control *sc) - { - int gen, type, zone; -@@ -5102,6 +5040,68 @@ retry: - return scanned; - } - -+static bool should_run_aging(struct lruvec *lruvec, unsigned long max_seq, -+ struct scan_control *sc, bool can_swap, unsigned long *nr_to_scan) -+{ -+ int gen, type, zone; -+ unsigned long old = 0; -+ unsigned long young = 0; -+ unsigned long total = 0; -+ struct lru_gen_folio *lrugen = &lruvec->lrugen; -+ struct mem_cgroup *memcg = lruvec_memcg(lruvec); -+ DEFINE_MIN_SEQ(lruvec); -+ -+ /* whether this lruvec is completely out of cold folios */ -+ if (min_seq[!can_swap] + MIN_NR_GENS > max_seq) { -+ *nr_to_scan = 0; -+ return true; -+ } -+ -+ for (type = !can_swap; type < ANON_AND_FILE; type++) { -+ unsigned long seq; -+ -+ for (seq = min_seq[type]; seq <= max_seq; seq++) { -+ unsigned long size = 0; -+ -+ gen = lru_gen_from_seq(seq); -+ -+ for (zone = 0; zone < MAX_NR_ZONES; zone++) -+ size += max(READ_ONCE(lrugen->nr_pages[gen][type][zone]), 0L); -+ -+ total += size; -+ if (seq == max_seq) -+ young += size; -+ else if (seq + MIN_NR_GENS == max_seq) -+ old += size; -+ } -+ } -+ -+ /* try to scrape all its memory if this memcg was deleted */ -+ *nr_to_scan = mem_cgroup_online(memcg) ? (total >> sc->priority) : total; -+ -+ /* -+ * The aging tries to be lazy to reduce the overhead, while the eviction -+ * stalls when the number of generations reaches MIN_NR_GENS. Hence, the -+ * ideal number of generations is MIN_NR_GENS+1. -+ */ -+ if (min_seq[!can_swap] + MIN_NR_GENS < max_seq) -+ return false; -+ -+ /* -+ * It's also ideal to spread pages out evenly, i.e., 1/(MIN_NR_GENS+1) -+ * of the total number of pages for each generation. A reasonable range -+ * for this average portion is [1/MIN_NR_GENS, 1/(MIN_NR_GENS+2)]. The -+ * aging cares about the upper bound of hot pages, while the eviction -+ * cares about the lower bound of cold pages. -+ */ -+ if (young * MIN_NR_GENS > total) -+ return true; -+ if (old * (MIN_NR_GENS + 2) < total) -+ return true; -+ -+ return false; -+} -+ - /* - * For future optimizations: - * 1. Defer try_to_inc_max_seq() to workqueues to reduce latency for memcg diff --git a/target/linux/generic/backport-6.1/020-v6.3-26-mm-multi-gen-LRU-per-node-lru_gen_page-lists.patch b/target/linux/generic/backport-6.1/020-v6.3-26-mm-multi-gen-LRU-per-node-lru_gen_page-lists.patch deleted file mode 100644 index 45789ff209..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-26-mm-multi-gen-LRU-per-node-lru_gen_page-lists.patch +++ /dev/null @@ -1,868 +0,0 @@ -From fa6363828d314e837c5f79e97ea5e8c0d2f7f062 Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Wed, 21 Dec 2022 21:19:04 -0700 -Subject: [PATCH 26/29] mm: multi-gen LRU: per-node lru_gen_folio lists - -For each node, memcgs are divided into two generations: the old and -the young. For each generation, memcgs are randomly sharded into -multiple bins to improve scalability. For each bin, an RCU hlist_nulls -is virtually divided into three segments: the head, the tail and the -default. - -An onlining memcg is added to the tail of a random bin in the old -generation. The eviction starts at the head of a random bin in the old -generation. The per-node memcg generation counter, whose reminder (mod -2) indexes the old generation, is incremented when all its bins become -empty. - -There are four operations: -1. MEMCG_LRU_HEAD, which moves an memcg to the head of a random bin in - its current generation (old or young) and updates its "seg" to - "head"; -2. MEMCG_LRU_TAIL, which moves an memcg to the tail of a random bin in - its current generation (old or young) and updates its "seg" to - "tail"; -3. MEMCG_LRU_OLD, which moves an memcg to the head of a random bin in - the old generation, updates its "gen" to "old" and resets its "seg" - to "default"; -4. MEMCG_LRU_YOUNG, which moves an memcg to the tail of a random bin - in the young generation, updates its "gen" to "young" and resets - its "seg" to "default". - -The events that trigger the above operations are: -1. Exceeding the soft limit, which triggers MEMCG_LRU_HEAD; -2. The first attempt to reclaim an memcg below low, which triggers - MEMCG_LRU_TAIL; -3. The first attempt to reclaim an memcg below reclaimable size - threshold, which triggers MEMCG_LRU_TAIL; -4. The second attempt to reclaim an memcg below reclaimable size - threshold, which triggers MEMCG_LRU_YOUNG; -5. Attempting to reclaim an memcg below min, which triggers - MEMCG_LRU_YOUNG; -6. Finishing the aging on the eviction path, which triggers - MEMCG_LRU_YOUNG; -7. Offlining an memcg, which triggers MEMCG_LRU_OLD. - -Note that memcg LRU only applies to global reclaim, and the -round-robin incrementing of their max_seq counters ensures the -eventual fairness to all eligible memcgs. For memcg reclaim, it still -relies on mem_cgroup_iter(). - -Link: https://lkml.kernel.org/r/20221222041905.2431096-7-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Johannes Weiner -Cc: Jonathan Corbet -Cc: Michael Larabel -Cc: Michal Hocko -Cc: Mike Rapoport -Cc: Roman Gushchin -Cc: Suren Baghdasaryan -Signed-off-by: Andrew Morton ---- - include/linux/memcontrol.h | 10 + - include/linux/mm_inline.h | 17 ++ - include/linux/mmzone.h | 117 +++++++++++- - mm/memcontrol.c | 16 ++ - mm/folio_alloc.c | 1 + - mm/vmscan.c | 373 +++++++++++++++++++++++++++++++++---- - 6 files changed, 499 insertions(+), 35 deletions(-) - ---- a/include/linux/memcontrol.h -+++ b/include/linux/memcontrol.h -@@ -790,6 +790,11 @@ static inline void obj_cgroup_put(struct - percpu_ref_put(&objcg->refcnt); - } - -+static inline bool mem_cgroup_tryget(struct mem_cgroup *memcg) -+{ -+ return !memcg || css_tryget(&memcg->css); -+} -+ - static inline void mem_cgroup_put(struct mem_cgroup *memcg) - { - if (memcg) -@@ -1290,6 +1295,11 @@ static inline void obj_cgroup_put(struct - { - } - -+static inline bool mem_cgroup_tryget(struct mem_cgroup *memcg) -+{ -+ return true; -+} -+ - static inline void mem_cgroup_put(struct mem_cgroup *memcg) - { - } ---- a/include/linux/mm_inline.h -+++ b/include/linux/mm_inline.h -@@ -122,6 +122,18 @@ static inline bool lru_gen_in_fault(void - return current->in_lru_fault; - } - -+#ifdef CONFIG_MEMCG -+static inline int lru_gen_memcg_seg(struct lruvec *lruvec) -+{ -+ return READ_ONCE(lruvec->lrugen.seg); -+} -+#else -+static inline int lru_gen_memcg_seg(struct lruvec *lruvec) -+{ -+ return 0; -+} -+#endif -+ - static inline int lru_gen_from_seq(unsigned long seq) - { - return seq % MAX_NR_GENS; -@@ -297,6 +309,11 @@ static inline bool lru_gen_in_fault(void - return false; - } - -+static inline int lru_gen_memcg_seg(struct lruvec *lruvec) -+{ -+ return 0; -+} -+ - static inline bool lru_gen_add_folio(struct lruvec *lruvec, struct folio *folio, bool reclaiming) - { - return false; ---- a/include/linux/mmzone.h -+++ b/include/linux/mmzone.h -@@ -7,6 +7,7 @@ - - #include - #include -+#include - #include - #include - #include -@@ -367,6 +368,15 @@ struct page_vma_mapped_walk; - #define LRU_GEN_MASK ((BIT(LRU_GEN_WIDTH) - 1) << LRU_GEN_PGOFF) - #define LRU_REFS_MASK ((BIT(LRU_REFS_WIDTH) - 1) << LRU_REFS_PGOFF) - -+/* see the comment on MEMCG_NR_GENS */ -+enum { -+ MEMCG_LRU_NOP, -+ MEMCG_LRU_HEAD, -+ MEMCG_LRU_TAIL, -+ MEMCG_LRU_OLD, -+ MEMCG_LRU_YOUNG, -+}; -+ - #ifdef CONFIG_LRU_GEN - - enum { -@@ -426,6 +436,14 @@ struct lru_gen_folio { - atomic_long_t refaulted[NR_HIST_GENS][ANON_AND_FILE][MAX_NR_TIERS]; - /* whether the multi-gen LRU is enabled */ - bool enabled; -+#ifdef CONFIG_MEMCG -+ /* the memcg generation this lru_gen_folio belongs to */ -+ u8 gen; -+ /* the list segment this lru_gen_folio belongs to */ -+ u8 seg; -+ /* per-node lru_gen_folio list for global reclaim */ -+ struct hlist_nulls_node list; -+#endif - }; - - enum { -@@ -479,12 +497,87 @@ void lru_gen_init_lruvec(struct lruvec * - void lru_gen_look_around(struct page_vma_mapped_walk *pvmw); - - #ifdef CONFIG_MEMCG -+ -+/* -+ * For each node, memcgs are divided into two generations: the old and the -+ * young. For each generation, memcgs are randomly sharded into multiple bins -+ * to improve scalability. For each bin, the hlist_nulls is virtually divided -+ * into three segments: the head, the tail and the default. -+ * -+ * An onlining memcg is added to the tail of a random bin in the old generation. -+ * The eviction starts at the head of a random bin in the old generation. The -+ * per-node memcg generation counter, whose reminder (mod MEMCG_NR_GENS) indexes -+ * the old generation, is incremented when all its bins become empty. -+ * -+ * There are four operations: -+ * 1. MEMCG_LRU_HEAD, which moves an memcg to the head of a random bin in its -+ * current generation (old or young) and updates its "seg" to "head"; -+ * 2. MEMCG_LRU_TAIL, which moves an memcg to the tail of a random bin in its -+ * current generation (old or young) and updates its "seg" to "tail"; -+ * 3. MEMCG_LRU_OLD, which moves an memcg to the head of a random bin in the old -+ * generation, updates its "gen" to "old" and resets its "seg" to "default"; -+ * 4. MEMCG_LRU_YOUNG, which moves an memcg to the tail of a random bin in the -+ * young generation, updates its "gen" to "young" and resets its "seg" to -+ * "default". -+ * -+ * The events that trigger the above operations are: -+ * 1. Exceeding the soft limit, which triggers MEMCG_LRU_HEAD; -+ * 2. The first attempt to reclaim an memcg below low, which triggers -+ * MEMCG_LRU_TAIL; -+ * 3. The first attempt to reclaim an memcg below reclaimable size threshold, -+ * which triggers MEMCG_LRU_TAIL; -+ * 4. The second attempt to reclaim an memcg below reclaimable size threshold, -+ * which triggers MEMCG_LRU_YOUNG; -+ * 5. Attempting to reclaim an memcg below min, which triggers MEMCG_LRU_YOUNG; -+ * 6. Finishing the aging on the eviction path, which triggers MEMCG_LRU_YOUNG; -+ * 7. Offlining an memcg, which triggers MEMCG_LRU_OLD. -+ * -+ * Note that memcg LRU only applies to global reclaim, and the round-robin -+ * incrementing of their max_seq counters ensures the eventual fairness to all -+ * eligible memcgs. For memcg reclaim, it still relies on mem_cgroup_iter(). -+ */ -+#define MEMCG_NR_GENS 2 -+#define MEMCG_NR_BINS 8 -+ -+struct lru_gen_memcg { -+ /* the per-node memcg generation counter */ -+ unsigned long seq; -+ /* each memcg has one lru_gen_folio per node */ -+ unsigned long nr_memcgs[MEMCG_NR_GENS]; -+ /* per-node lru_gen_folio list for global reclaim */ -+ struct hlist_nulls_head fifo[MEMCG_NR_GENS][MEMCG_NR_BINS]; -+ /* protects the above */ -+ spinlock_t lock; -+}; -+ -+void lru_gen_init_pgdat(struct pglist_data *pgdat); -+ - void lru_gen_init_memcg(struct mem_cgroup *memcg); - void lru_gen_exit_memcg(struct mem_cgroup *memcg); --#endif -+void lru_gen_online_memcg(struct mem_cgroup *memcg); -+void lru_gen_offline_memcg(struct mem_cgroup *memcg); -+void lru_gen_release_memcg(struct mem_cgroup *memcg); -+void lru_gen_rotate_memcg(struct lruvec *lruvec, int op); -+ -+#else /* !CONFIG_MEMCG */ -+ -+#define MEMCG_NR_GENS 1 -+ -+struct lru_gen_memcg { -+}; -+ -+static inline void lru_gen_init_pgdat(struct pglist_data *pgdat) -+{ -+} -+ -+#endif /* CONFIG_MEMCG */ - - #else /* !CONFIG_LRU_GEN */ - -+static inline void lru_gen_init_pgdat(struct pglist_data *pgdat) -+{ -+} -+ - static inline void lru_gen_init_lruvec(struct lruvec *lruvec) - { - } -@@ -494,6 +587,7 @@ static inline void lru_gen_look_around(s - } - - #ifdef CONFIG_MEMCG -+ - static inline void lru_gen_init_memcg(struct mem_cgroup *memcg) - { - } -@@ -501,7 +595,24 @@ static inline void lru_gen_init_memcg(st - static inline void lru_gen_exit_memcg(struct mem_cgroup *memcg) - { - } --#endif -+ -+static inline void lru_gen_online_memcg(struct mem_cgroup *memcg) -+{ -+} -+ -+static inline void lru_gen_offline_memcg(struct mem_cgroup *memcg) -+{ -+} -+ -+static inline void lru_gen_release_memcg(struct mem_cgroup *memcg) -+{ -+} -+ -+static inline void lru_gen_rotate_memcg(struct lruvec *lruvec, int op) -+{ -+} -+ -+#endif /* CONFIG_MEMCG */ - - #endif /* CONFIG_LRU_GEN */ - -@@ -1219,6 +1330,8 @@ typedef struct pglist_data { - #ifdef CONFIG_LRU_GEN - /* kswap mm walk data */ - struct lru_gen_mm_walk mm_walk; -+ /* lru_gen_folio list */ -+ struct lru_gen_memcg memcg_lru; - #endif - - CACHELINE_PADDING(_pad2_); ---- a/mm/memcontrol.c -+++ b/mm/memcontrol.c -@@ -477,6 +477,16 @@ static void mem_cgroup_update_tree(struc - struct mem_cgroup_per_node *mz; - struct mem_cgroup_tree_per_node *mctz; - -+ if (lru_gen_enabled()) { -+ struct lruvec *lruvec = &memcg->nodeinfo[nid]->lruvec; -+ -+ /* see the comment on MEMCG_NR_GENS */ -+ if (soft_limit_excess(memcg) && lru_gen_memcg_seg(lruvec) != MEMCG_LRU_HEAD) -+ lru_gen_rotate_memcg(lruvec, MEMCG_LRU_HEAD); -+ -+ return; -+ } -+ - mctz = soft_limit_tree.rb_tree_per_node[nid]; - if (!mctz) - return; -@@ -3522,6 +3532,9 @@ unsigned long mem_cgroup_soft_limit_recl - struct mem_cgroup_tree_per_node *mctz; - unsigned long excess; - -+ if (lru_gen_enabled()) -+ return 0; -+ - if (order > 0) - return 0; - -@@ -5382,6 +5395,7 @@ static int mem_cgroup_css_online(struct - if (unlikely(mem_cgroup_is_root(memcg))) - queue_delayed_work(system_unbound_wq, &stats_flush_dwork, - 2UL*HZ); -+ lru_gen_online_memcg(memcg); - return 0; - offline_kmem: - memcg_offline_kmem(memcg); -@@ -5413,6 +5427,7 @@ static void mem_cgroup_css_offline(struc - memcg_offline_kmem(memcg); - reparent_shrinker_deferred(memcg); - wb_memcg_offline(memcg); -+ lru_gen_offline_memcg(memcg); - - drain_all_stock(memcg); - -@@ -5424,6 +5439,7 @@ static void mem_cgroup_css_released(stru - struct mem_cgroup *memcg = mem_cgroup_from_css(css); - - invalidate_reclaim_iterators(memcg); -+ lru_gen_release_memcg(memcg); - } - - static void mem_cgroup_css_free(struct cgroup_subsys_state *css) ---- a/mm/page_alloc.c -+++ b/mm/page_alloc.c -@@ -7957,6 +7957,7 @@ static void __init free_area_init_node(i - pgdat_set_deferred_range(pgdat); - - free_area_init_core(pgdat); -+ lru_gen_init_pgdat(pgdat); - } - - static void __init free_area_init_memoryless_node(int nid) ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -54,6 +54,8 @@ - #include - #include - #include -+#include -+#include - - #include - #include -@@ -134,11 +136,6 @@ struct scan_control { - /* Always discard instead of demoting to lower tier memory */ - unsigned int no_demotion:1; - --#ifdef CONFIG_LRU_GEN -- /* help kswapd make better choices among multiple memcgs */ -- unsigned long last_reclaimed; --#endif -- - /* Allocation order */ - s8 order; - -@@ -3160,6 +3157,9 @@ DEFINE_STATIC_KEY_ARRAY_FALSE(lru_gen_ca - for ((type) = 0; (type) < ANON_AND_FILE; (type)++) \ - for ((zone) = 0; (zone) < MAX_NR_ZONES; (zone)++) - -+#define get_memcg_gen(seq) ((seq) % MEMCG_NR_GENS) -+#define get_memcg_bin(bin) ((bin) % MEMCG_NR_BINS) -+ - static struct lruvec *get_lruvec(struct mem_cgroup *memcg, int nid) - { - struct pglist_data *pgdat = NODE_DATA(nid); -@@ -4443,8 +4443,7 @@ done: - if (sc->priority <= DEF_PRIORITY - 2) - wait_event_killable(lruvec->mm_state.wait, - max_seq < READ_ONCE(lrugen->max_seq)); -- -- return max_seq < READ_ONCE(lrugen->max_seq); -+ return false; - } - - VM_WARN_ON_ONCE(max_seq != READ_ONCE(lrugen->max_seq)); -@@ -4517,8 +4516,6 @@ static void lru_gen_age_node(struct pgli - - VM_WARN_ON_ONCE(!current_is_kswapd()); - -- sc->last_reclaimed = sc->nr_reclaimed; -- - /* check the order to exclude compaction-induced reclaim */ - if (!min_ttl || sc->order || sc->priority == DEF_PRIORITY) - return; -@@ -5107,8 +5104,7 @@ static bool should_run_aging(struct lruv - * 1. Defer try_to_inc_max_seq() to workqueues to reduce latency for memcg - * reclaim. - */ --static unsigned long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, -- bool can_swap) -+static long get_nr_to_scan(struct lruvec *lruvec, struct scan_control *sc, bool can_swap) - { - unsigned long nr_to_scan; - struct mem_cgroup *memcg = lruvec_memcg(lruvec); -@@ -5125,10 +5121,8 @@ static unsigned long get_nr_to_scan(stru - if (sc->priority == DEF_PRIORITY) - return nr_to_scan; - -- try_to_inc_max_seq(lruvec, max_seq, sc, can_swap, false); -- - /* skip this lruvec as it's low on cold folios */ -- return 0; -+ return try_to_inc_max_seq(lruvec, max_seq, sc, can_swap, false) ? -1 : 0; - } - - static unsigned long get_nr_to_reclaim(struct scan_control *sc) -@@ -5137,29 +5131,18 @@ static unsigned long get_nr_to_reclaim(s - if (!global_reclaim(sc)) - return -1; - -- /* discount the previous progress for kswapd */ -- if (current_is_kswapd()) -- return sc->nr_to_reclaim + sc->last_reclaimed; -- - return max(sc->nr_to_reclaim, compact_gap(sc->order)); - } - --static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) -+static bool try_to_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) - { -- struct blk_plug plug; -+ long nr_to_scan; - unsigned long scanned = 0; - unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); - -- lru_add_drain(); -- -- blk_start_plug(&plug); -- -- set_mm_walk(lruvec_pgdat(lruvec)); -- - while (true) { - int delta; - int swappiness; -- unsigned long nr_to_scan; - - if (sc->may_swap) - swappiness = get_swappiness(lruvec, sc); -@@ -5169,7 +5152,7 @@ static void lru_gen_shrink_lruvec(struct - swappiness = 0; - - nr_to_scan = get_nr_to_scan(lruvec, sc, swappiness); -- if (!nr_to_scan) -+ if (nr_to_scan <= 0) - break; - - delta = evict_folios(lruvec, sc, swappiness); -@@ -5186,10 +5169,250 @@ static void lru_gen_shrink_lruvec(struct - cond_resched(); - } - -+ /* whether try_to_inc_max_seq() was successful */ -+ return nr_to_scan < 0; -+} -+ -+static int shrink_one(struct lruvec *lruvec, struct scan_control *sc) -+{ -+ bool success; -+ unsigned long scanned = sc->nr_scanned; -+ unsigned long reclaimed = sc->nr_reclaimed; -+ int seg = lru_gen_memcg_seg(lruvec); -+ struct mem_cgroup *memcg = lruvec_memcg(lruvec); -+ struct pglist_data *pgdat = lruvec_pgdat(lruvec); -+ -+ /* see the comment on MEMCG_NR_GENS */ -+ if (!lruvec_is_sizable(lruvec, sc)) -+ return seg != MEMCG_LRU_TAIL ? MEMCG_LRU_TAIL : MEMCG_LRU_YOUNG; -+ -+ mem_cgroup_calculate_protection(NULL, memcg); -+ -+ if (mem_cgroup_below_min(memcg)) -+ return MEMCG_LRU_YOUNG; -+ -+ if (mem_cgroup_below_low(memcg)) { -+ /* see the comment on MEMCG_NR_GENS */ -+ if (seg != MEMCG_LRU_TAIL) -+ return MEMCG_LRU_TAIL; -+ -+ memcg_memory_event(memcg, MEMCG_LOW); -+ } -+ -+ success = try_to_shrink_lruvec(lruvec, sc); -+ -+ shrink_slab(sc->gfp_mask, pgdat->node_id, memcg, sc->priority); -+ -+ vmpressure(sc->gfp_mask, memcg, false, sc->nr_scanned - scanned, -+ sc->nr_reclaimed - reclaimed); -+ -+ sc->nr_reclaimed += current->reclaim_state->reclaimed_slab; -+ current->reclaim_state->reclaimed_slab = 0; -+ -+ return success ? MEMCG_LRU_YOUNG : 0; -+} -+ -+#ifdef CONFIG_MEMCG -+ -+static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc) -+{ -+ int gen; -+ int bin; -+ int first_bin; -+ struct lruvec *lruvec; -+ struct lru_gen_folio *lrugen; -+ const struct hlist_nulls_node *pos; -+ int op = 0; -+ struct mem_cgroup *memcg = NULL; -+ unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); -+ -+ bin = first_bin = prandom_u32_max(MEMCG_NR_BINS); -+restart: -+ gen = get_memcg_gen(READ_ONCE(pgdat->memcg_lru.seq)); -+ -+ rcu_read_lock(); -+ -+ hlist_nulls_for_each_entry_rcu(lrugen, pos, &pgdat->memcg_lru.fifo[gen][bin], list) { -+ if (op) -+ lru_gen_rotate_memcg(lruvec, op); -+ -+ mem_cgroup_put(memcg); -+ -+ lruvec = container_of(lrugen, struct lruvec, lrugen); -+ memcg = lruvec_memcg(lruvec); -+ -+ if (!mem_cgroup_tryget(memcg)) { -+ op = 0; -+ memcg = NULL; -+ continue; -+ } -+ -+ rcu_read_unlock(); -+ -+ op = shrink_one(lruvec, sc); -+ -+ if (sc->nr_reclaimed >= nr_to_reclaim) -+ goto success; -+ -+ rcu_read_lock(); -+ } -+ -+ rcu_read_unlock(); -+ -+ /* restart if raced with lru_gen_rotate_memcg() */ -+ if (gen != get_nulls_value(pos)) -+ goto restart; -+ -+ /* try the rest of the bins of the current generation */ -+ bin = get_memcg_bin(bin + 1); -+ if (bin != first_bin) -+ goto restart; -+success: -+ if (op) -+ lru_gen_rotate_memcg(lruvec, op); -+ -+ mem_cgroup_put(memcg); -+} -+ -+static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) -+{ -+ struct blk_plug plug; -+ -+ VM_WARN_ON_ONCE(global_reclaim(sc)); -+ -+ lru_add_drain(); -+ -+ blk_start_plug(&plug); -+ -+ set_mm_walk(lruvec_pgdat(lruvec)); -+ -+ if (try_to_shrink_lruvec(lruvec, sc)) -+ lru_gen_rotate_memcg(lruvec, MEMCG_LRU_YOUNG); -+ -+ clear_mm_walk(); -+ -+ blk_finish_plug(&plug); -+} -+ -+#else /* !CONFIG_MEMCG */ -+ -+static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc) -+{ -+ BUILD_BUG(); -+} -+ -+static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) -+{ -+ BUILD_BUG(); -+} -+ -+#endif -+ -+static void set_initial_priority(struct pglist_data *pgdat, struct scan_control *sc) -+{ -+ int priority; -+ unsigned long reclaimable; -+ struct lruvec *lruvec = mem_cgroup_lruvec(NULL, pgdat); -+ -+ if (sc->priority != DEF_PRIORITY || sc->nr_to_reclaim < MIN_LRU_BATCH) -+ return; -+ /* -+ * Determine the initial priority based on ((total / MEMCG_NR_GENS) >> -+ * priority) * reclaimed_to_scanned_ratio = nr_to_reclaim, where the -+ * estimated reclaimed_to_scanned_ratio = inactive / total. -+ */ -+ reclaimable = node_page_state(pgdat, NR_INACTIVE_FILE); -+ if (get_swappiness(lruvec, sc)) -+ reclaimable += node_page_state(pgdat, NR_INACTIVE_ANON); -+ -+ reclaimable /= MEMCG_NR_GENS; -+ -+ /* round down reclaimable and round up sc->nr_to_reclaim */ -+ priority = fls_long(reclaimable) - 1 - fls_long(sc->nr_to_reclaim - 1); -+ -+ sc->priority = clamp(priority, 0, DEF_PRIORITY); -+} -+ -+static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control *sc) -+{ -+ struct blk_plug plug; -+ unsigned long reclaimed = sc->nr_reclaimed; -+ -+ VM_WARN_ON_ONCE(!global_reclaim(sc)); -+ -+ lru_add_drain(); -+ -+ blk_start_plug(&plug); -+ -+ set_mm_walk(pgdat); -+ -+ set_initial_priority(pgdat, sc); -+ -+ if (current_is_kswapd()) -+ sc->nr_reclaimed = 0; -+ -+ if (mem_cgroup_disabled()) -+ shrink_one(&pgdat->__lruvec, sc); -+ else -+ shrink_many(pgdat, sc); -+ -+ if (current_is_kswapd()) -+ sc->nr_reclaimed += reclaimed; -+ - clear_mm_walk(); - - blk_finish_plug(&plug); -+ -+ /* kswapd should never fail */ -+ pgdat->kswapd_failures = 0; -+} -+ -+#ifdef CONFIG_MEMCG -+void lru_gen_rotate_memcg(struct lruvec *lruvec, int op) -+{ -+ int seg; -+ int old, new; -+ int bin = prandom_u32_max(MEMCG_NR_BINS); -+ struct pglist_data *pgdat = lruvec_pgdat(lruvec); -+ -+ spin_lock(&pgdat->memcg_lru.lock); -+ -+ VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); -+ -+ seg = 0; -+ new = old = lruvec->lrugen.gen; -+ -+ /* see the comment on MEMCG_NR_GENS */ -+ if (op == MEMCG_LRU_HEAD) -+ seg = MEMCG_LRU_HEAD; -+ else if (op == MEMCG_LRU_TAIL) -+ seg = MEMCG_LRU_TAIL; -+ else if (op == MEMCG_LRU_OLD) -+ new = get_memcg_gen(pgdat->memcg_lru.seq); -+ else if (op == MEMCG_LRU_YOUNG) -+ new = get_memcg_gen(pgdat->memcg_lru.seq + 1); -+ else -+ VM_WARN_ON_ONCE(true); -+ -+ hlist_nulls_del_rcu(&lruvec->lrugen.list); -+ -+ if (op == MEMCG_LRU_HEAD || op == MEMCG_LRU_OLD) -+ hlist_nulls_add_head_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[new][bin]); -+ else -+ hlist_nulls_add_tail_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[new][bin]); -+ -+ pgdat->memcg_lru.nr_memcgs[old]--; -+ pgdat->memcg_lru.nr_memcgs[new]++; -+ -+ lruvec->lrugen.gen = new; -+ WRITE_ONCE(lruvec->lrugen.seg, seg); -+ -+ if (!pgdat->memcg_lru.nr_memcgs[old] && old == get_memcg_gen(pgdat->memcg_lru.seq)) -+ WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); -+ -+ spin_unlock(&pgdat->memcg_lru.lock); - } -+#endif - - /****************************************************************************** - * state change -@@ -5647,11 +5870,11 @@ static int run_cmd(char cmd, int memcg_i - - if (!mem_cgroup_disabled()) { - rcu_read_lock(); -+ - memcg = mem_cgroup_from_id(memcg_id); --#ifdef CONFIG_MEMCG -- if (memcg && !css_tryget(&memcg->css)) -+ if (!mem_cgroup_tryget(memcg)) - memcg = NULL; --#endif -+ - rcu_read_unlock(); - - if (!memcg) -@@ -5799,6 +6022,19 @@ void lru_gen_init_lruvec(struct lruvec * - } - - #ifdef CONFIG_MEMCG -+ -+void lru_gen_init_pgdat(struct pglist_data *pgdat) -+{ -+ int i, j; -+ -+ spin_lock_init(&pgdat->memcg_lru.lock); -+ -+ for (i = 0; i < MEMCG_NR_GENS; i++) { -+ for (j = 0; j < MEMCG_NR_BINS; j++) -+ INIT_HLIST_NULLS_HEAD(&pgdat->memcg_lru.fifo[i][j], i); -+ } -+} -+ - void lru_gen_init_memcg(struct mem_cgroup *memcg) - { - INIT_LIST_HEAD(&memcg->mm_list.fifo); -@@ -5822,7 +6058,69 @@ void lru_gen_exit_memcg(struct mem_cgrou - } - } - } --#endif -+ -+void lru_gen_online_memcg(struct mem_cgroup *memcg) -+{ -+ int gen; -+ int nid; -+ int bin = prandom_u32_max(MEMCG_NR_BINS); -+ -+ for_each_node(nid) { -+ struct pglist_data *pgdat = NODE_DATA(nid); -+ struct lruvec *lruvec = get_lruvec(memcg, nid); -+ -+ spin_lock(&pgdat->memcg_lru.lock); -+ -+ VM_WARN_ON_ONCE(!hlist_nulls_unhashed(&lruvec->lrugen.list)); -+ -+ gen = get_memcg_gen(pgdat->memcg_lru.seq); -+ -+ hlist_nulls_add_tail_rcu(&lruvec->lrugen.list, &pgdat->memcg_lru.fifo[gen][bin]); -+ pgdat->memcg_lru.nr_memcgs[gen]++; -+ -+ lruvec->lrugen.gen = gen; -+ -+ spin_unlock(&pgdat->memcg_lru.lock); -+ } -+} -+ -+void lru_gen_offline_memcg(struct mem_cgroup *memcg) -+{ -+ int nid; -+ -+ for_each_node(nid) { -+ struct lruvec *lruvec = get_lruvec(memcg, nid); -+ -+ lru_gen_rotate_memcg(lruvec, MEMCG_LRU_OLD); -+ } -+} -+ -+void lru_gen_release_memcg(struct mem_cgroup *memcg) -+{ -+ int gen; -+ int nid; -+ -+ for_each_node(nid) { -+ struct pglist_data *pgdat = NODE_DATA(nid); -+ struct lruvec *lruvec = get_lruvec(memcg, nid); -+ -+ spin_lock(&pgdat->memcg_lru.lock); -+ -+ VM_WARN_ON_ONCE(hlist_nulls_unhashed(&lruvec->lrugen.list)); -+ -+ gen = lruvec->lrugen.gen; -+ -+ hlist_nulls_del_rcu(&lruvec->lrugen.list); -+ pgdat->memcg_lru.nr_memcgs[gen]--; -+ -+ if (!pgdat->memcg_lru.nr_memcgs[gen] && gen == get_memcg_gen(pgdat->memcg_lru.seq)) -+ WRITE_ONCE(pgdat->memcg_lru.seq, pgdat->memcg_lru.seq + 1); -+ -+ spin_unlock(&pgdat->memcg_lru.lock); -+ } -+} -+ -+#endif /* CONFIG_MEMCG */ - - static int __init init_lru_gen(void) - { -@@ -5849,6 +6147,10 @@ static void lru_gen_shrink_lruvec(struct - { - } - -+static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control *sc) -+{ -+} -+ - #endif /* CONFIG_LRU_GEN */ - - static void shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc) -@@ -5862,7 +6164,7 @@ static void shrink_lruvec(struct lruvec - bool proportional_reclaim; - struct blk_plug plug; - -- if (lru_gen_enabled()) { -+ if (lru_gen_enabled() && !global_reclaim(sc)) { - lru_gen_shrink_lruvec(lruvec, sc); - return; - } -@@ -6105,6 +6407,11 @@ static void shrink_node(pg_data_t *pgdat - struct lruvec *target_lruvec; - bool reclaimable = false; - -+ if (lru_gen_enabled() && global_reclaim(sc)) { -+ lru_gen_shrink_node(pgdat, sc); -+ return; -+ } -+ - target_lruvec = mem_cgroup_lruvec(sc->target_mem_cgroup, pgdat); - - again: diff --git a/target/linux/generic/backport-6.1/020-v6.3-27-mm-multi-gen-LRU-clarify-scan_control-flags.patch b/target/linux/generic/backport-6.1/020-v6.3-27-mm-multi-gen-LRU-clarify-scan_control-flags.patch deleted file mode 100644 index 89f7ed30af..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-27-mm-multi-gen-LRU-clarify-scan_control-flags.patch +++ /dev/null @@ -1,196 +0,0 @@ -From 93147736b5b3a21bea24313bfc7a696829932009 Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Wed, 21 Dec 2022 21:19:05 -0700 -Subject: [PATCH 27/29] mm: multi-gen LRU: clarify scan_control flags - -Among the flags in scan_control: -1. sc->may_swap, which indicates swap constraint due to memsw.max, is - supported as usual. -2. sc->proactive, which indicates reclaim by memory.reclaim, may not - opportunistically skip the aging path, since it is considered less - latency sensitive. -3. !(sc->gfp_mask & __GFP_IO), which indicates IO constraint, lowers - swappiness to prioritize file LRU, since clean file folios are more - likely to exist. -4. sc->may_writefolio and sc->may_unmap, which indicates opportunistic - reclaim, are rejected, since unmapped clean folios are already - prioritized. Scanning for more of them is likely futile and can - cause high reclaim latency when there is a large number of memcgs. - -The rest are handled by the existing code. - -Link: https://lkml.kernel.org/r/20221222041905.2431096-8-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Johannes Weiner -Cc: Jonathan Corbet -Cc: Michael Larabel -Cc: Michal Hocko -Cc: Mike Rapoport -Cc: Roman Gushchin -Cc: Suren Baghdasaryan -Signed-off-by: Andrew Morton ---- - mm/vmscan.c | 55 +++++++++++++++++++++++++++-------------------------- - 1 file changed, 28 insertions(+), 27 deletions(-) - ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -3185,6 +3185,9 @@ static int get_swappiness(struct lruvec - struct mem_cgroup *memcg = lruvec_memcg(lruvec); - struct pglist_data *pgdat = lruvec_pgdat(lruvec); - -+ if (!sc->may_swap) -+ return 0; -+ - if (!can_demote(pgdat->node_id, sc) && - mem_cgroup_get_nr_swap_pages(memcg) < MIN_LRU_BATCH) - return 0; -@@ -4226,7 +4229,7 @@ static void walk_mm(struct lruvec *lruve - } while (err == -EAGAIN); - } - --static struct lru_gen_mm_walk *set_mm_walk(struct pglist_data *pgdat) -+static struct lru_gen_mm_walk *set_mm_walk(struct pglist_data *pgdat, bool force_alloc) - { - struct lru_gen_mm_walk *walk = current->reclaim_state->mm_walk; - -@@ -4234,7 +4237,7 @@ static struct lru_gen_mm_walk *set_mm_wa - VM_WARN_ON_ONCE(walk); - - walk = &pgdat->mm_walk; -- } else if (!pgdat && !walk) { -+ } else if (!walk && force_alloc) { - VM_WARN_ON_ONCE(current_is_kswapd()); - - walk = kzalloc(sizeof(*walk), __GFP_HIGH | __GFP_NOMEMALLOC | __GFP_NOWARN); -@@ -4420,7 +4423,7 @@ static bool try_to_inc_max_seq(struct lr - goto done; - } - -- walk = set_mm_walk(NULL); -+ walk = set_mm_walk(NULL, true); - if (!walk) { - success = iterate_mm_list_nowalk(lruvec, max_seq); - goto done; -@@ -4489,8 +4492,6 @@ static bool lruvec_is_reclaimable(struct - struct mem_cgroup *memcg = lruvec_memcg(lruvec); - DEFINE_MIN_SEQ(lruvec); - -- VM_WARN_ON_ONCE(sc->memcg_low_reclaim); -- - /* see the comment on lru_gen_folio */ - gen = lru_gen_from_seq(min_seq[LRU_GEN_FILE]); - birth = READ_ONCE(lruvec->lrugen.timestamps[gen]); -@@ -4746,12 +4747,8 @@ static bool isolate_folio(struct lruvec - { - bool success; - -- /* unmapping inhibited */ -- if (!sc->may_unmap && folio_mapped(folio)) -- return false; -- - /* swapping inhibited */ -- if (!(sc->may_writepage && (sc->gfp_mask & __GFP_IO)) && -+ if (!(sc->gfp_mask & __GFP_IO) && - (folio_test_dirty(folio) || - (folio_test_anon(folio) && !folio_test_swapcache(folio)))) - return false; -@@ -4848,9 +4845,8 @@ static int scan_folios(struct lruvec *lr - __count_vm_events(PGSCAN_ANON + type, isolated); - - /* -- * There might not be eligible pages due to reclaim_idx, may_unmap and -- * may_writepage. Check the remaining to prevent livelock if it's not -- * making progress. -+ * There might not be eligible pages due to reclaim_idx. Check the -+ * remaining to prevent livelock if it's not making progress. - */ - return isolated || !remaining ? scanned : 0; - } -@@ -5110,8 +5106,7 @@ static long get_nr_to_scan(struct lruvec - struct mem_cgroup *memcg = lruvec_memcg(lruvec); - DEFINE_MAX_SEQ(lruvec); - -- if (mem_cgroup_below_min(memcg) || -- (mem_cgroup_below_low(memcg) && !sc->memcg_low_reclaim)) -+ if (mem_cgroup_below_min(memcg)) - return 0; - - if (!should_run_aging(lruvec, max_seq, sc, can_swap, &nr_to_scan)) -@@ -5139,17 +5134,14 @@ static bool try_to_shrink_lruvec(struct - long nr_to_scan; - unsigned long scanned = 0; - unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); -+ int swappiness = get_swappiness(lruvec, sc); -+ -+ /* clean file folios are more likely to exist */ -+ if (swappiness && !(sc->gfp_mask & __GFP_IO)) -+ swappiness = 1; - - while (true) { - int delta; -- int swappiness; -- -- if (sc->may_swap) -- swappiness = get_swappiness(lruvec, sc); -- else if (!cgroup_reclaim(sc) && get_swappiness(lruvec, sc)) -- swappiness = 1; -- else -- swappiness = 0; - - nr_to_scan = get_nr_to_scan(lruvec, sc, swappiness); - if (nr_to_scan <= 0) -@@ -5279,12 +5271,13 @@ static void lru_gen_shrink_lruvec(struct - struct blk_plug plug; - - VM_WARN_ON_ONCE(global_reclaim(sc)); -+ VM_WARN_ON_ONCE(!sc->may_writepage || !sc->may_unmap); - - lru_add_drain(); - - blk_start_plug(&plug); - -- set_mm_walk(lruvec_pgdat(lruvec)); -+ set_mm_walk(NULL, sc->proactive); - - if (try_to_shrink_lruvec(lruvec, sc)) - lru_gen_rotate_memcg(lruvec, MEMCG_LRU_YOUNG); -@@ -5340,11 +5333,19 @@ static void lru_gen_shrink_node(struct p - - VM_WARN_ON_ONCE(!global_reclaim(sc)); - -+ /* -+ * Unmapped clean folios are already prioritized. Scanning for more of -+ * them is likely futile and can cause high reclaim latency when there -+ * is a large number of memcgs. -+ */ -+ if (!sc->may_writepage || !sc->may_unmap) -+ goto done; -+ - lru_add_drain(); - - blk_start_plug(&plug); - -- set_mm_walk(pgdat); -+ set_mm_walk(NULL, sc->proactive); - - set_initial_priority(pgdat, sc); - -@@ -5362,7 +5363,7 @@ static void lru_gen_shrink_node(struct p - clear_mm_walk(); - - blk_finish_plug(&plug); -- -+done: - /* kswapd should never fail */ - pgdat->kswapd_failures = 0; - } -@@ -5934,7 +5935,7 @@ static ssize_t lru_gen_seq_write(struct - set_task_reclaim_state(current, &sc.reclaim_state); - flags = memalloc_noreclaim_save(); - blk_start_plug(&plug); -- if (!set_mm_walk(NULL)) { -+ if (!set_mm_walk(NULL, true)) { - err = -ENOMEM; - goto done; - } diff --git a/target/linux/generic/backport-6.1/020-v6.3-28-mm-multi-gen-LRU-simplify-arch_has_hw_pte_young-chec.patch b/target/linux/generic/backport-6.1/020-v6.3-28-mm-multi-gen-LRU-simplify-arch_has_hw_pte_young-chec.patch deleted file mode 100644 index 367f93363b..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-28-mm-multi-gen-LRU-simplify-arch_has_hw_pte_young-chec.patch +++ /dev/null @@ -1,34 +0,0 @@ -From cf3297e4c7a928da8b2b2f0baff2f9c69ea57952 Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Wed, 21 Dec 2022 21:19:06 -0700 -Subject: [PATCH 28/29] mm: multi-gen LRU: simplify arch_has_hw_pte_young() - check - -Scanning page tables when hardware does not set the accessed bit has -no real use cases. - -Link: https://lkml.kernel.org/r/20221222041905.2431096-9-yuzhao@google.com -Signed-off-by: Yu Zhao -Cc: Johannes Weiner -Cc: Jonathan Corbet -Cc: Michael Larabel -Cc: Michal Hocko -Cc: Mike Rapoport -Cc: Roman Gushchin -Cc: Suren Baghdasaryan -Signed-off-by: Andrew Morton ---- - mm/vmscan.c | 2 +- - 1 file changed, 1 insertion(+), 1 deletion(-) - ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -4418,7 +4418,7 @@ static bool try_to_inc_max_seq(struct lr - * handful of PTEs. Spreading the work out over a period of time usually - * is less efficient, but it avoids bursty page faults. - */ -- if (!force_scan && !(arch_has_hw_pte_young() && get_cap(LRU_GEN_MM_WALK))) { -+ if (!arch_has_hw_pte_young() || !get_cap(LRU_GEN_MM_WALK)) { - success = iterate_mm_list_nowalk(lruvec, max_seq); - goto done; - } diff --git a/target/linux/generic/backport-6.1/020-v6.3-29-mm-multi-gen-LRU-avoid-futile-retries.patch b/target/linux/generic/backport-6.1/020-v6.3-29-mm-multi-gen-LRU-avoid-futile-retries.patch deleted file mode 100644 index b9eb5f694e..0000000000 --- a/target/linux/generic/backport-6.1/020-v6.3-29-mm-multi-gen-LRU-avoid-futile-retries.patch +++ /dev/null @@ -1,88 +0,0 @@ -From cc67f962cc53f6e1dfa92eb85b7b26fe83a3c66f Mon Sep 17 00:00:00 2001 -From: Yu Zhao -Date: Mon, 13 Feb 2023 00:53:22 -0700 -Subject: [PATCH 29/29] mm: multi-gen LRU: avoid futile retries - -Recall that the per-node memcg LRU has two generations and they alternate -when the last memcg (of a given node) is moved from one to the other. -Each generation is also sharded into multiple bins to improve scalability. -A reclaimer starts with a random bin (in the old generation) and, if it -fails, it will retry, i.e., to try the rest of the bins. - -If a reclaimer fails with the last memcg, it should move this memcg to the -young generation first, which causes the generations to alternate, and -then retry. Otherwise, the retries will be futile because all other bins -are empty. - -Link: https://lkml.kernel.org/r/20230213075322.1416966-1-yuzhao@google.com -Fixes: e4dde56cd208 ("mm: multi-gen LRU: per-node lru_gen_folio lists") -Signed-off-by: Yu Zhao -Reported-by: T.J. Mercier -Signed-off-by: Andrew Morton ---- - mm/vmscan.c | 25 +++++++++++++++---------- - 1 file changed, 15 insertions(+), 10 deletions(-) - ---- a/mm/vmscan.c -+++ b/mm/vmscan.c -@@ -5208,18 +5208,20 @@ static int shrink_one(struct lruvec *lru - - static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc) - { -+ int op; - int gen; - int bin; - int first_bin; - struct lruvec *lruvec; - struct lru_gen_folio *lrugen; -+ struct mem_cgroup *memcg; - const struct hlist_nulls_node *pos; -- int op = 0; -- struct mem_cgroup *memcg = NULL; - unsigned long nr_to_reclaim = get_nr_to_reclaim(sc); - - bin = first_bin = prandom_u32_max(MEMCG_NR_BINS); - restart: -+ op = 0; -+ memcg = NULL; - gen = get_memcg_gen(READ_ONCE(pgdat->memcg_lru.seq)); - - rcu_read_lock(); -@@ -5243,14 +5245,22 @@ restart: - - op = shrink_one(lruvec, sc); - -- if (sc->nr_reclaimed >= nr_to_reclaim) -- goto success; -- - rcu_read_lock(); -+ -+ if (sc->nr_reclaimed >= nr_to_reclaim) -+ break; - } - - rcu_read_unlock(); - -+ if (op) -+ lru_gen_rotate_memcg(lruvec, op); -+ -+ mem_cgroup_put(memcg); -+ -+ if (sc->nr_reclaimed >= nr_to_reclaim) -+ return; -+ - /* restart if raced with lru_gen_rotate_memcg() */ - if (gen != get_nulls_value(pos)) - goto restart; -@@ -5259,11 +5269,6 @@ restart: - bin = get_memcg_bin(bin + 1); - if (bin != first_bin) - goto restart; --success: -- if (op) -- lru_gen_rotate_memcg(lruvec, op); -- -- mem_cgroup_put(memcg); - } - - static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc)