From 4ca3a69bcb6875c3f20802522c1b4fc56bb14608 Mon Sep 17 00:00:00 2001 From: Sasha Levin Date: Fri, 22 Feb 2013 16:32:28 -0800 Subject: [PATCH] mm/ksm.c: use new hashtable implementation Switch ksm to use the new hashtable implementation. This reduces the amount of generic unrelated code in the ksm module. Signed-off-by: Sasha Levin Acked-by: Hugh Dickins Cc: Michal Hocko Cc: Konstantin Khlebnikov Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/ksm.c | 30 ++++++++++++------------------ 1 file changed, 12 insertions(+), 18 deletions(-) diff --git a/mm/ksm.c b/mm/ksm.c index e1f1f278075f..d3842b206f8a 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -33,7 +33,7 @@ #include #include #include -#include +#include #include #include @@ -156,9 +156,8 @@ struct rmap_item { static struct rb_root root_stable_tree = RB_ROOT; static struct rb_root root_unstable_tree = RB_ROOT; -#define MM_SLOTS_HASH_SHIFT 10 -#define MM_SLOTS_HASH_HEADS (1 << MM_SLOTS_HASH_SHIFT) -static struct hlist_head mm_slots_hash[MM_SLOTS_HASH_HEADS]; +#define MM_SLOTS_HASH_BITS 10 +static DEFINE_HASHTABLE(mm_slots_hash, MM_SLOTS_HASH_BITS); static struct mm_slot ksm_mm_head = { .mm_list = LIST_HEAD_INIT(ksm_mm_head.mm_list), @@ -275,26 +274,21 @@ static inline void free_mm_slot(struct mm_slot *mm_slot) static struct mm_slot *get_mm_slot(struct mm_struct *mm) { - struct mm_slot *mm_slot; - struct hlist_head *bucket; struct hlist_node *node; + struct mm_slot *slot; + + hash_for_each_possible(mm_slots_hash, slot, node, link, (unsigned long)mm) + if (slot->mm == mm) + return slot; - bucket = &mm_slots_hash[hash_ptr(mm, MM_SLOTS_HASH_SHIFT)]; - hlist_for_each_entry(mm_slot, node, bucket, link) { - if (mm == mm_slot->mm) - return mm_slot; - } return NULL; } static void insert_to_mm_slots_hash(struct mm_struct *mm, struct mm_slot *mm_slot) { - struct hlist_head *bucket; - - bucket = &mm_slots_hash[hash_ptr(mm, MM_SLOTS_HASH_SHIFT)]; mm_slot->mm = mm; - hlist_add_head(&mm_slot->link, bucket); + hash_add(mm_slots_hash, &mm_slot->link, (unsigned long)mm); } static inline int in_stable_tree(struct rmap_item *rmap_item) @@ -647,7 +641,7 @@ static int unmerge_and_remove_all_rmap_items(void) ksm_scan.mm_slot = list_entry(mm_slot->mm_list.next, struct mm_slot, mm_list); if (ksm_test_exit(mm)) { - hlist_del(&mm_slot->link); + hash_del(&mm_slot->link); list_del(&mm_slot->mm_list); spin_unlock(&ksm_mmlist_lock); @@ -1392,7 +1386,7 @@ next_mm: * or when all VM_MERGEABLE areas have been unmapped (and * mmap_sem then protects against race with MADV_MERGEABLE). */ - hlist_del(&slot->link); + hash_del(&slot->link); list_del(&slot->mm_list); spin_unlock(&ksm_mmlist_lock); @@ -1559,7 +1553,7 @@ void __ksm_exit(struct mm_struct *mm) mm_slot = get_mm_slot(mm); if (mm_slot && ksm_scan.mm_slot != mm_slot) { if (!mm_slot->rmap_list) { - hlist_del(&mm_slot->link); + hash_del(&mm_slot->link); list_del(&mm_slot->mm_list); easy_to_free = 1; } else { -- 2.30.2