Joonsoo Kim [Thu, 17 Mar 2016 21:19:29 +0000 (14:19 -0700)]
mm/page_ref: add tracepoint to track down page reference manipulation
CMA allocation should be guaranteed to succeed by definition, but,
unfortunately, it would be failed sometimes. It is hard to track down
the problem, because it is related to page reference manipulation and we
don't have any facility to analyze it.
This patch adds tracepoints to track down page reference manipulation.
With it, we can find exact reason of failure and can fix the problem.
Following is an example of tracepoint output. (note: this example is
stale version that printing flags as the number. Recent version will
print it as human readable string.)
<...>-9018 [004] 92.678375: page_ref_set: pfn=0x17ac9 flags=0x0 count=1 mapcount=0 mapping=(nil) mt=4 val=1
<...>-9018 [004] 92.678378: kernel_stack:
=> get_page_from_freelist (
ffffffff81176659)
=> __alloc_pages_nodemask (
ffffffff81176d22)
=> alloc_pages_vma (
ffffffff811bf675)
=> handle_mm_fault (
ffffffff8119e693)
=> __do_page_fault (
ffffffff810631ea)
=> trace_do_page_fault (
ffffffff81063543)
=> do_async_page_fault (
ffffffff8105c40a)
=> async_page_fault (
ffffffff817581d8)
[snip]
<...>-9018 [004] 92.678379: page_ref_mod: pfn=0x17ac9 flags=0x40048 count=2 mapcount=1 mapping=0xffff880015a78dc1 mt=4 val=1
[snip]
...
...
<...>-9131 [001] 93.174468: test_pages_isolated: start_pfn=0x17800 end_pfn=0x17c00 fin_pfn=0x17ac9 ret=fail
[snip]
<...>-9018 [004] 93.174843: page_ref_mod_and_test: pfn=0x17ac9 flags=0x40068 count=0 mapcount=0 mapping=0xffff880015a78dc1 mt=4 val=-1 ret=1
=> release_pages (
ffffffff8117c9e4)
=> free_pages_and_swap_cache (
ffffffff811b0697)
=> tlb_flush_mmu_free (
ffffffff81199616)
=> tlb_finish_mmu (
ffffffff8119a62c)
=> exit_mmap (
ffffffff811a53f7)
=> mmput (
ffffffff81073f47)
=> do_exit (
ffffffff810794e9)
=> do_group_exit (
ffffffff81079def)
=> SyS_exit_group (
ffffffff81079e74)
=> entry_SYSCALL_64_fastpath (
ffffffff817560b6)
This output shows that problem comes from exit path. In exit path, to
improve performance, pages are not freed immediately. They are gathered
and processed by batch. During this process, migration cannot be
possible and CMA allocation is failed. This problem is hard to find
without this page reference tracepoint facility.
Enabling this feature bloat kernel text 30 KB in my configuration.
text data bss dec hex filename
12127327 2243616 1507328 15878271 f2487f vmlinux_disabled
12157208 2258880 1507328 15923416 f2f8d8 vmlinux_enabled
Note that, due to header file dependency problem between mm.h and
tracepoint.h, this feature has to open code the static key functions for
tracepoints. Proposed by Steven Rostedt in following link.
https://lkml.org/lkml/2015/12/9/699
[arnd@arndb.de: crypto/async_pq: use __free_page() instead of put_page()]
[iamjoonsoo.kim@lge.com: fix build failure for xtensa]
[akpm@linux-foundation.org: tweak Kconfig text, per Vlastimil]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Thu, 17 Mar 2016 21:19:26 +0000 (14:19 -0700)]
mm: introduce page reference manipulation functions
The success of CMA allocation largely depends on the success of
migration and key factor of it is page reference count. Until now, page
reference is manipulated by direct calling atomic functions so we cannot
follow up who and where manipulate it. Then, it is hard to find actual
reason of CMA allocation failure. CMA allocation should be guaranteed
to succeed so finding offending place is really important.
In this patch, call sites where page reference is manipulated are
converted to introduced wrapper function. This is preparation step to
add tracepoint to each page reference manipulation function. With this
facility, we can easily find reason of CMA allocation failure. There is
no functional change in this patch.
In addition, this patch also converts reference read sites. It will
help a second step that renames page._count to something else and
prevents later attempt to direct access to it (Suggested by Andrew).
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mel Gorman [Thu, 17 Mar 2016 21:19:23 +0000 (14:19 -0700)]
mm: thp: set THP defrag by default to madvise and add a stall-free defrag option
THP defrag is enabled by default to direct reclaim/compact but not wake
kswapd in the event of a THP allocation failure. The problem is that
THP allocation requests potentially enter reclaim/compaction. This
potentially incurs a severe stall that is not guaranteed to be offset by
reduced TLB misses. While there has been considerable effort to reduce
the impact of reclaim/compaction, it is still a high cost and workloads
that should fit in memory fail to do so. Specifically, a simple
anon/file streaming workload will enter direct reclaim on NUMA at least
even though the working set size is 80% of RAM. It's been years and
it's time to throw in the towel.
First, this patch defines THP defrag as follows;
madvise: A failed allocation will direct reclaim/compact if the application requests it
never: Neither reclaim/compact nor wake kswapd
defer: A failed allocation will wake kswapd/kcompactd
always: A failed allocation will direct reclaim/compact (historical behaviour)
khugepaged defrag will enter direct/reclaim but not wake kswapd.
Next it sets the default defrag option to be "madvise" to only enter
direct reclaim/compaction for applications that specifically requested
it.
Lastly, it removes a check from the page allocator slowpath that is
related to __GFP_THISNODE to allow "defer" to work. The callers that
really cares are slub/slab and they are updated accordingly. The slab
one may be surprising because it also corrects a comment as kswapd was
never woken up by that path.
This means that a THP fault will no longer stall for most applications
by default and the ideal for most users that get THP if they are
immediately available. There are still options for users that prefer a
stall at startup of a new application by either restoring historical
behaviour with "always" or pick a half-way point with "defer" where
kswapd does some of the work in the background and wakes kcompactd if
necessary. THP defrag for khugepaged remains enabled and will enter
direct/reclaim but no wakeup kswapd or kcompactd.
After this patch a THP allocation failure will quickly fallback and rely
on khugepaged to recover the situation at some time in the future. In
some cases, this will reduce THP usage but the benefit of THP is hard to
measure and not a universal win where as a stall to reclaim/compaction
is definitely measurable and can be painful.
The first test for this is using "usemem" to read a large file and write
a large anonymous mapping (to avoid the zero page) multiple times. The
total size of the mappings is 80% of RAM and the benchmark simply
measures how long it takes to complete. It uses multiple threads to see
if that is a factor. On UMA, the performance is almost identical so is
not reported but on NUMA, we see this
usemem
4.4.0 4.4.0
kcompactd-v1r1 nodefrag-v1r3
Amean System-1 102.86 ( 0.00%) 46.81 ( 54.50%)
Amean System-4 37.85 ( 0.00%) 34.02 ( 10.12%)
Amean System-7 48.12 ( 0.00%) 46.89 ( 2.56%)
Amean System-12 51.98 ( 0.00%) 56.96 ( -9.57%)
Amean System-21 80.16 ( 0.00%) 79.05 ( 1.39%)
Amean System-30 110.71 ( 0.00%) 107.17 ( 3.20%)
Amean System-48 127.98 ( 0.00%) 124.83 ( 2.46%)
Amean Elapsd-1 185.84 ( 0.00%) 105.51 ( 43.23%)
Amean Elapsd-4 26.19 ( 0.00%) 25.58 ( 2.33%)
Amean Elapsd-7 21.65 ( 0.00%) 21.62 ( 0.16%)
Amean Elapsd-12 18.58 ( 0.00%) 17.94 ( 3.43%)
Amean Elapsd-21 17.53 ( 0.00%) 16.60 ( 5.33%)
Amean Elapsd-30 17.45 ( 0.00%) 17.13 ( 1.84%)
Amean Elapsd-48 15.40 ( 0.00%) 15.27 ( 0.82%)
For a single thread, the benchmark completes 43.23% faster with this
patch applied with smaller benefits as the thread increases. Similar,
notice the large reduction in most cases in system CPU usage. The
overall CPU time is
4.4.0 4.4.0
kcompactd-v1r1 nodefrag-v1r3
User 10357.65 10438.33
System 3988.88 3543.94
Elapsed 2203.01 1634.41
Which is substantial. Now, the reclaim figures
4.4.0 4.4.0
kcompactd-v1r1nodefrag-v1r3
Minor Faults
128458477 278352931
Major Faults
2174976 225
Swap Ins
16904701 0
Swap Outs
17359627 0
Allocation stalls 43611 0
DMA allocs 0 0
DMA32 allocs
19832646 19448017
Normal allocs
614488453 580941839
Movable allocs 0 0
Direct pages scanned
24163800 0
Kswapd pages scanned 0 0
Kswapd pages reclaimed 0 0
Direct pages reclaimed
20691346 0
Compaction stalls 42263 0
Compaction success 938 0
Compaction failures 41325 0
This patch eliminates almost all swapping and direct reclaim activity.
There is still overhead but it's from NUMA balancing which does not
identify that it's pointless trying to do anything with this workload.
I also tried the thpscale benchmark which forces a corner case where
compaction can be used heavily and measures the latency of whether base
or huge pages were used
thpscale Fault Latencies
4.4.0 4.4.0
kcompactd-v1r1 nodefrag-v1r3
Amean fault-base-1 5288.84 ( 0.00%) 2817.12 ( 46.73%)
Amean fault-base-3 6365.53 ( 0.00%) 3499.11 ( 45.03%)
Amean fault-base-5 6526.19 ( 0.00%) 4363.06 ( 33.15%)
Amean fault-base-7 7142.25 ( 0.00%) 4858.08 ( 31.98%)
Amean fault-base-12 13827.64 ( 0.00%) 10292.11 ( 25.57%)
Amean fault-base-18 18235.07 ( 0.00%) 13788.84 ( 24.38%)
Amean fault-base-24 21597.80 ( 0.00%) 24388.03 (-12.92%)
Amean fault-base-30 26754.15 ( 0.00%) 19700.55 ( 26.36%)
Amean fault-base-32 26784.94 ( 0.00%) 19513.57 ( 27.15%)
Amean fault-huge-1 4223.96 ( 0.00%) 2178.57 ( 48.42%)
Amean fault-huge-3 2194.77 ( 0.00%) 2149.74 ( 2.05%)
Amean fault-huge-5 2569.60 ( 0.00%) 2346.95 ( 8.66%)
Amean fault-huge-7 3612.69 ( 0.00%) 2997.70 ( 17.02%)
Amean fault-huge-12 3301.75 ( 0.00%) 6727.02 (-103.74%)
Amean fault-huge-18 6696.47 ( 0.00%) 6685.72 ( 0.16%)
Amean fault-huge-24 8000.72 ( 0.00%) 9311.43 (-16.38%)
Amean fault-huge-30 13305.55 ( 0.00%) 9750.45 ( 26.72%)
Amean fault-huge-32 9981.71 ( 0.00%) 10316.06 ( -3.35%)
The average time to fault pages is substantially reduced in the majority
of caseds but with the obvious caveat that fewer THPs are actually used
in this adverse workload
4.4.0 4.4.0
kcompactd-v1r1 nodefrag-v1r3
Percentage huge-1 0.71 ( 0.00%) 14.04 (1865.22%)
Percentage huge-3 10.77 ( 0.00%) 33.05 (206.85%)
Percentage huge-5 60.39 ( 0.00%) 38.51 (-36.23%)
Percentage huge-7 45.97 ( 0.00%) 34.57 (-24.79%)
Percentage huge-12 68.12 ( 0.00%) 40.07 (-41.17%)
Percentage huge-18 64.93 ( 0.00%) 47.82 (-26.35%)
Percentage huge-24 62.69 ( 0.00%) 44.23 (-29.44%)
Percentage huge-30 43.49 ( 0.00%) 55.38 ( 27.34%)
Percentage huge-32 50.72 ( 0.00%) 51.90 ( 2.35%)
4.4.0 4.4.0
kcompactd-v1r1nodefrag-v1r3
Minor Faults
37429143 47564000
Major Faults 1916 1558
Swap Ins 1466 1079
Swap Outs
2936863 149626
Allocation stalls 62510 3
DMA allocs 0 0
DMA32 allocs
6566458 6401314
Normal allocs
216361697 216538171
Movable allocs 0 0
Direct pages scanned
25977580 17998
Kswapd pages scanned 0
3638931
Kswapd pages reclaimed 0 207236
Direct pages reclaimed
8833714 88
Compaction stalls 103349 5
Compaction success 270 4
Compaction failures 103079 1
Note again that while this does swap as it's an aggressive workload, the
direct relcim activity and allocation stalls is substantially reduced.
There is some kswapd activity but ftrace showed that the kswapd activity
was due to normal wakeups from 4K pages being allocated.
Compaction-related stalls and activity are almost eliminated.
I also tried the stutter benchmark. For this, I do not have figures for
NUMA but it's something that does impact UMA so I'll report what is
available
stutter
4.4.0 4.4.0
kcompactd-v1r1 nodefrag-v1r3
Min mmap 7.3571 ( 0.00%) 7.3438 ( 0.18%)
1st-qrtle mmap 7.5278 ( 0.00%) 17.9200 (-138.05%)
2nd-qrtle mmap 7.6818 ( 0.00%) 21.6055 (-181.25%)
3rd-qrtle mmap 11.0889 ( 0.00%) 21.8881 (-97.39%)
Max-90% mmap 27.8978 ( 0.00%) 22.1632 ( 20.56%)
Max-93% mmap 28.3202 ( 0.00%) 22.3044 ( 21.24%)
Max-95% mmap 28.5600 ( 0.00%) 22.4580 ( 21.37%)
Max-99% mmap 29.6032 ( 0.00%) 25.5216 ( 13.79%)
Max mmap 4109.7289 ( 0.00%) 4813.9832 (-17.14%)
Mean mmap 12.4474 ( 0.00%) 19.3027 (-55.07%)
This benchmark is trying to fault an anonymous mapping while there is a
heavy IO load -- a scenario that desktop users used to complain about
frequently. This shows a mix because the ideal case of mapping with THP
is not hit as often. However, note that 99% of the mappings complete
13.79% faster. The CPU usage here is particularly interesting
4.4.0 4.4.0
kcompactd-v1r1nodefrag-v1r3
User 67.50 0.99
System 1327.88 91.30
Elapsed 2079.00 2128.98
And once again we look at the reclaim figures
4.4.0 4.4.0
kcompactd-v1r1nodefrag-v1r3
Minor Faults
335241922 1314582827
Major Faults 715 819
Swap Ins 0 0
Swap Outs 0 0
Allocation stalls 532723 0
DMA allocs 0 0
DMA32 allocs
1822364341 1177950222
Normal allocs
1815640808 1517844854
Movable allocs 0 0
Direct pages scanned
21892772 0
Kswapd pages scanned
20015890 41879484
Kswapd pages reclaimed
19961986 41822072
Direct pages reclaimed
21892741 0
Compaction stalls
1065755 0
Compaction success 514 0
Compaction failures
1065241 0
Allocation stalls and all direct reclaim activity is eliminated as well
as compaction-related stalls.
THP gives impressive gains in some cases but only if they are quickly
available. We're not going to reach the point where they are completely
free so lets take the costs out of the fast paths finally and defer the
cost to kswapd, kcompactd and khugepaged where it belongs.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Thu, 17 Mar 2016 21:19:19 +0000 (14:19 -0700)]
mm, mempool: only set __GFP_NOMEMALLOC if there are free elements
If an oom killed thread calls mempool_alloc(), it is possible that it'll
loop forever if there are no elements on the freelist since
__GFP_NOMEMALLOC prevents it from accessing needed memory reserves in
oom conditions.
Only set __GFP_NOMEMALLOC if there are elements on the freelist. If
there are no free elements, allow allocations without the bit set so
that memory reserves can be accessed if needed.
Additionally, using mempool_alloc() with __GFP_NOMEMALLOC is not
supported since the implementation can loop forever without accessing
memory reserves when needed.
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Satoru Takeuchi [Thu, 17 Mar 2016 21:19:17 +0000 (14:19 -0700)]
mm: remove unnecessary description about a non-exist gfp flag
Since __GFP_NOACCOUNT was removed by commit
20b5c3039863 ("Revert 'gfp:
add __GFP_NOACCOUNT'"), its description is not necessary.
Signed-off-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Thu, 17 Mar 2016 21:19:14 +0000 (14:19 -0700)]
mm: scale kswapd watermarks in proportion to memory
In machines with 140G of memory and enterprise flash storage, we have
seen read and write bursts routinely exceed the kswapd watermarks and
cause thundering herds in direct reclaim. Unfortunately, the only way
to tune kswapd aggressiveness is through adjusting min_free_kbytes - the
system's emergency reserves - which is entirely unrelated to the
system's latency requirements. In order to get kswapd to maintain a
250M buffer of free memory, the emergency reserves need to be set to 1G.
That is a lot of memory wasted for no good reason.
On the other hand, it's reasonable to assume that allocation bursts and
overall allocation concurrency scale with memory capacity, so it makes
sense to make kswapd aggressiveness a function of that as well.
Change the kswapd watermark scale factor from the currently fixed 25% of
the tunable emergency reserve to a tunable 0.1% of memory.
Beyond 1G of memory, this will produce bigger watermark steps than the
current formula in default settings. Ensure that the new formula never
chooses steps smaller than that, i.e. 25% of the emergency reserve.
On a 140G machine, this raises the default watermark steps - the
distance between min and low, and low and high - from 16M to 143M.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kirill A. Shutemov [Thu, 17 Mar 2016 21:19:11 +0000 (14:19 -0700)]
mm: cleanup *pte_alloc* interfaces
There are few things about *pte_alloc*() helpers worth cleaning up:
- 'vma' argument is unused, let's drop it;
- most __pte_alloc() callers do speculative check for pmd_none(),
before taking ptl: let's introduce pte_alloc() macro which does
the check.
The only direct user of __pte_alloc left is userfaultfd, which has
different expectation about atomicity wrt pmd.
- pte_alloc_map() and pte_alloc_map_lock() are redefined using
pte_alloc().
[sudeep.holla@arm.com: fix build for arm64 hugetlbpage]
[sfr@canb.auug.org.au: fix arch/arm/mm/mmu.c some more]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Igor Redko [Thu, 17 Mar 2016 21:19:08 +0000 (14:19 -0700)]
virtio_balloon: export 'available' memory to balloon statistics
Add a new field, VIRTIO_BALLOON_S_AVAIL, to virtio_balloon memory
statistics protocol, corresponding to 'Available' in /proc/meminfo.
It indicates to the hypervisor how big the balloon can be inflated
without pushing the guest system to swap.
Signed-off-by: Igor Redko <redkoi@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Igor Redko [Thu, 17 Mar 2016 21:19:05 +0000 (14:19 -0700)]
mm/page_alloc.c: calculate 'available' memory in a separate function
Add a new field, VIRTIO_BALLOON_S_AVAIL, to virtio_balloon memory
statistics protocol, corresponding to 'Available' in /proc/meminfo.
It indicates to the hypervisor how big the balloon can be inflated
without pushing the guest system to swap. This metric would be very
useful in VM orchestration software to improve memory management of
different VMs under overcommit.
This patch (of 2):
Factor out calculation of the available memory counter into a separate
exportable function, in order to be able to use it in other parts of the
kernel.
In particular, it appears a relevant metric to report to the hypervisor
via virtio-balloon statistics interface (in a followup patch).
Signed-off-by: Igor Redko <redkoi@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yang Shi [Thu, 17 Mar 2016 21:19:02 +0000 (14:19 -0700)]
mm/Kconfig: remove redundant arch depend for memory hotplug
MEMORY_HOTPLUG already depends on ARCH_ENABLE_MEMORY_HOTPLUG which is
selected by the supported architectures, so the following arch depend is
unnecessary.
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vineet Gupta [Thu, 17 Mar 2016 21:18:59 +0000 (14:18 -0700)]
ARC, thp: remove infrastructure for handling splitting PMDs
With THP refcounting work, no need to mark PMDs splitting.
(ARC got missed under the sweeping arch change as THP support was likely
not present in orig baseline)
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Aneesh Kumar K.V [Thu, 17 Mar 2016 21:18:56 +0000 (14:18 -0700)]
mm/thp/migration: switch from flush_tlb_range to flush_pmd_tlb_range
We remove one instace of flush_tlb_range here. That was added by commit
f714f4f20e59 ("mm: numa: call MMU notifiers on THP migration"). But the
pmdp_huge_clear_flush_notify should have done the require flush for us.
Hence remove the extra flush.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kirill A. Shutemov [Thu, 17 Mar 2016 21:18:53 +0000 (14:18 -0700)]
mm, tracing: refresh __def_vmaflag_names
Get list of VMA flags up-to-date and sort it to match VM_* definition
order.
[vbabka@suse.cz: add a note above vmaflag definitions to update the names when changing]
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Ryabinin [Thu, 17 Mar 2016 21:18:50 +0000 (14:18 -0700)]
mm: deduplicate memory overcommitment code
Currently we have two copies of the same code which implements memory
overcommitment logic. Let's move it into mm/util.c and hence avoid
duplication. No functional changes here.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrey Ryabinin [Thu, 17 Mar 2016 21:18:48 +0000 (14:18 -0700)]
mm: move max_map_count bits into mm.h
max_map_count sysctl unrelated to scheduler. Move its bits from
include/linux/sched/sysctl.h to include/linux/mm.h.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kirill A. Shutemov [Thu, 17 Mar 2016 21:18:45 +0000 (14:18 -0700)]
thp, vmstats: count deferred split events
Count how many times we put a THP in split queue. Currently, it happens
on partial unmap of a THP.
Rapidly growing value can indicate that an application behaves
unfriendly wrt THP: often fault in huge page and then unmap part of it.
This leads to unnecessary memory fragmentation and the application may
require tuning.
The event also can help with debugging kernel [mis-]behaviour.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:18:42 +0000 (14:18 -0700)]
mm: workingset: make shadow node shrinker memcg aware
Workingset code was recently made memcg aware, but shadow node shrinker
is still global. As a result, one small cgroup can consume all memory
available for shadow nodes, possibly hurting other cgroups by reclaiming
their shadow nodes, even though reclaim distances stored in its shadow
nodes have no effect. To avoid this, we need to make shadow node
shrinker memcg aware.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:18:39 +0000 (14:18 -0700)]
mm: workingset: size shadow nodes lru basing on file cache size
A page is activated on refault if the refault distance stored in the
corresponding shadow entry is less than the number of active file pages.
Since active file pages can't occupy more than half memory, we assume
that the maximal effective refault distance can't be greater than half
the number of present pages and size the shadow nodes lru list
appropriately. Generally speaking, this assumption is correct, but it
can result in wasting a considerable chunk of memory on stale shadow
nodes in case the portion of file pages is small, e.g. if a workload
mostly uses anonymous memory.
To sort this out, we need to compute the size of shadow nodes lru basing
not on the maximal possible, but the current size of file cache. We
could take the size of active file lru for the maximal refault distance,
but active lru is pretty unstable - it can shrink dramatically at
runtime possibly disrupting workingset detection logic.
Instead we assume that the maximal refault distance equals half the
total number of file cache pages. This will protect us against active
file lru size fluctuations while still being correct, because size of
active lru is normally maintained lower than size of inactive lru.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:18:36 +0000 (14:18 -0700)]
radix-tree: account radix_tree_node to memory cgroup
Allocation of radix_tree_node objects can be easily triggered from
userspace, so we should account them to memory cgroup. Besides, we need
them accounted for making shadow node shrinker per memcg (see
mm/workingset.c).
A tricky thing about accounting radix_tree_node objects is that they are
mostly allocated through radix_tree_preload(), so we can't just set
SLAB_ACCOUNT for radix_tree_node_cachep - that would likely result in a
lot of unrelated cgroups using objects from each other's caches.
One way to overcome this would be making radix tree preloads per memcg,
but that would probably look cumbersome and overcomplicated.
Instead, we make radix_tree_node_alloc() first try to allocate from the
cache with __GFP_ACCOUNT, no matter if the caller has preloaded or not,
and only if it fails fall back on using per cpu preloads. This should
make most allocations accounted.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:18:33 +0000 (14:18 -0700)]
mm: memcontrol: zap memcg_kmem_online helper
As kmem accounting is now either enabled for all cgroups or disabled
system-wide, there's no point in having memcg_kmem_online() helper -
instead one can use memcg_kmem_enabled() and mem_cgroup_online(), as
shrink_slab() now does.
There are only two places left where this helper is used -
__memcg_kmem_charge() and memcg_create_kmem_cache(). The former can
only be called if memcg_kmem_enabled() returned true. Since the cgroup
it operates on is online, mem_cgroup_is_root() check will be enough.
memcg_create_kmem_cache() can't use mem_cgroup_online() helper instead
of memcg_kmem_online(), because it relies on the fact that in
memcg_offline_kmem() memcg->kmem_state is changed before
memcg_deactivate_kmem_caches() is called, but there we can just
open-code the check.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:18:30 +0000 (14:18 -0700)]
mm: vmscan: pass root_mem_cgroup instead of NULL to memcg aware shrinker
It's just convenient to implement a memcg aware shrinker when you know
that shrink_control->memcg != NULL unless memcg_kmem_enabled() returns
false.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:18:27 +0000 (14:18 -0700)]
mm: memcontrol: enable kmem accounting for all cgroups in the legacy hierarchy
Workingset code was recently made memcg aware, but shadow node shrinker
is still global. As a result, one small cgroup can consume all memory
available for shadow nodes, possibly hurting other cgroups by reclaiming
their shadow nodes, even though reclaim distances stored in its shadow
nodes have no effect. To avoid this, we need to make shadow node
shrinker memcg aware.
The actual work is done in patch 6 of the series. Patches 1 and 2
prepare memcg/shrinker infrastructure for the change. Patch 3 is just a
collateral cleanup. Patch 4 makes radix_tree_node accounted, which is
necessary for making shadow node shrinker memcg aware. Patch 5 reduces
shadow nodes overhead in case workload mostly uses anonymous pages.
This patch:
Currently, in the legacy hierarchy kmem accounting is off for all
cgroups by default and must be enabled explicitly by writing something
to memory.kmem.limit_in_bytes. Since we don't support reclaim on
hitting kmem limit, nor do we have any plans to implement it, this is
likely to be -1, just to enable kmem accounting and limit kernel memory
consumption by the memory.limit_in_bytes along with user memory.
This user API was introduced when the implementation of kmem accounting
lacked slab shrinker support and hence was useless in practice. Things
have changed since then - slab shrinkers were made memcg aware, the
accounting overhead seems to be negligible, and a failure to charge a
kmem allocation should not have critical consequences, because we only
account those kernel objects that should be safe to fail. That's why
kmem accounting is enabled by default for all cgroups in the default
hierarchy, which will eventually replace the legacy one.
The ability to enable kmem accounting for some cgroups while keeping it
disabled for others is getting difficult to maintain. E.g. to make
shadow node shrinker memcg aware (see mm/workingset.c), we need to know
the relationship between the number of shadow nodes allocated for a
cgroup and the size of its lru list. If kmem accounting is enabled for
all cgroups there is no problem, but what should we do if kmem
accounting is enabled only for half of cgroups? We've no other choice
but use global lru stats while scanning root cgroup's shadow nodes, but
that would be wrong if kmem accounting was enabled for all cgroups
(which is the case if the unified hierarchy is used), in which case we
should use lru stats of the root cgroup's lruvec.
That being said, let's enable kmem accounting for all memory cgroups by
default. If one finds it unstable or too costly, it can always be
disabled system-wide by passing cgroup.memory=nokmem to the kernel at
boot time.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Denys Vlasenko [Thu, 17 Mar 2016 21:18:24 +0000 (14:18 -0700)]
include/linux/page-flags.h: force inlining of selected page flag modifications
Sometimes gcc mysteriously doesn't inline
very small functions we expect to be inlined. See
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122
With this .config:
http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os,
the following functions get deinlined many times.
Examples of disassembly:
<SetPageUptodate> (43 copies, 141 calls):
55 push %rbp
48 89 e5 mov %rsp,%rbp
f0 80 0f 08 lock orb $0x8,(%rdi)
5d pop %rbp
c3 retq
<PagePrivate> (10 copies, 134 calls):
48 8b 07 mov (%rdi),%rax
55 push %rbp
48 89 e5 mov %rsp,%rbp
48 c1 e8 0b shr $0xb,%rax
83 e0 01 and $0x1,%eax
5d pop %rbp
c3 retq
This patch fixes this via s/inline/__always_inline/.
Code size decrease after the patch is ~7k:
text data bss dec hex filename
92125002 20826048 36417536 149368586 8e72f0a vmlinux
92118087 20826112 36417536 149361735 8e71447 vmlinux7_pageops_after
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Denys Vlasenko [Thu, 17 Mar 2016 21:18:21 +0000 (14:18 -0700)]
bufferhead: force inlining of buffer head flag operations
With both gcc 4.7.2 and 4.9.2, sometimes gcc mysteriously doesn't inline
very small functions we expect to be inlined. See
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66122
With this .config:
http://busybox.net/~vda/kernel_config_OPTIMIZE_INLINING_and_Os,
set_buffer_foo(), clear_buffer_foo() and similar functions get deinlined
about 60 times. Examples of disassembly:
<set_buffer_mapped> (14 copies, 43 calls):
55 push %rbp
48 89 e5 mov %rsp,%rbp
f0 80 0f 20 lock orb $0x20,(%rdi)
5d pop %rbp
c3 retq
<buffer_mapped> (3 copies, 34 calls):
48 8b 07 mov (%rdi),%rax
55 push %rbp
48 89 e5 mov %rsp,%rbp
48 c1 e8 05 shr $0x5,%rax
83 e0 01 and $0x1,%eax
5d pop %rbp
c3 retq
<set_buffer_new> (5 copies, 13 calls):
55 push %rbp
48 89 e5 mov %rsp,%rbp
f0 80 0f 40 lock orb $0x40,(%rdi)
5d pop %rbp
c3 retq
This patch fixes this via s/inline/__always_inline/.
This decreases vmlinux by about 3 kbytes.
text data bss dec hex filename
88200439 19905208 36421632 144527279 89d4faf vmlinux2
88197239 19905240 36421632 144524111 89d434f vmlinux
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Konstantin Khlebnikov [Thu, 17 Mar 2016 21:18:18 +0000 (14:18 -0700)]
tools/vm/page-types.c: add memory cgroup dumping and filtering
This adds two command line keys:
-c|--cgroup path|@inode Walk only pages owned by this memory cgroup
-C|--list-cgroup Show memory cgroup inodes
[vdavydov@virtuozzo.com: opt_cgroup should be uint64_t. Fix conflicts with "tools/vm/page-types.c: support swap entry"]
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Thu, 17 Mar 2016 21:18:15 +0000 (14:18 -0700)]
mm, kswapd: replace kswapd compaction with waking up kcompactd
Similarly to direct reclaim/compaction, kswapd attempts to combine
reclaim and compaction to attempt making memory allocation of given
order available.
The details differ from direct reclaim e.g. in having high watermark as
a goal. The code involved in kswapd's reclaim/compaction decisions has
evolved to be quite complex.
Testing reveals that it doesn't actually work in at least one scenario,
and closer inspection suggests that it could be greatly simplified
without compromising on the goal (make high-order page available) or
efficiency (don't reclaim too much). The simplification relieas of
doing all compaction in kcompactd, which is simply woken up when high
watermarks are reached by kswapd's reclaim.
The scenario where kswapd compaction doesn't work was found with mmtests
test stress-highalloc configured to attempt order-9 allocations without
direct reclaim, just waking up kswapd. There was no compaction attempt
from kswapd during the whole test. Some added instrumentation shows
what happens:
- balance_pgdat() sets end_zone to Normal, as it's not balanced
- reclaim is attempted on DMA zone, which sets nr_attempted to 99, but
it cannot reclaim anything, so sc.nr_reclaimed is 0
- for zones DMA32 and Normal, kswapd_shrink_zone uses testorder=0, so
it merely checks if high watermarks were reached for base pages.
This is true, so no reclaim is attempted. For DMA, testorder=0
wasn't used, as compaction_suitable() returned COMPACT_SKIPPED
- even though the pgdat_needs_compaction flag wasn't set to false, no
compaction happens due to the condition sc.nr_reclaimed >
nr_attempted being false (as 0 < 99)
- priority-- due to nr_reclaimed being 0, repeat until priority reaches
0 pgdat_balanced() is false as only the small zone DMA appears
balanced (curiously in that check, watermark appears OK and
compaction_suitable() returns COMPACT_PARTIAL, because a lower
classzone_idx is used there)
Now, even if it was decided that reclaim shouldn't be attempted on the
DMA zone, the scenario would be the same, as (sc.nr_reclaimed=0 >
nr_attempted=0) is also false. The condition really should use >= as
the comment suggests. Then there is a mismatch in the check for setting
pgdat_needs_compaction to false using low watermark, while the rest uses
high watermark, and who knows what other subtlety. Hopefully this
demonstrates that this is unsustainable.
Luckily we can simplify this a lot. The reclaim/compaction decisions
make sense for direct reclaim scenario, but in kswapd, our primary goal
is to reach high watermark in order-0 pages. Afterwards we can attempt
compaction just once. Unlike direct reclaim, we don't reclaim extra
pages (over the high watermark), the current code already disallows it
for good reasons.
After this patch, we simply wake up kcompactd to process the pgdat,
after we have either succeeded or failed to reach the high watermarks in
kswapd, which goes to sleep. We pass kswapd's order and classzone_idx,
so kcompactd can apply the same criteria to determine which zones are
worth compacting. Note that we use the classzone_idx from
wakeup_kswapd(), not balanced_classzone_idx which can include higher
zones that kswapd tried to balance too, but didn't consider them in
pgdat_balanced().
Since kswapd now cannot create high-order pages itself, we need to
adjust how it determines the zones to be balanced. The key element here
is adding a "highorder" parameter to zone_balanced, which, when set to
false, makes it consider only order-0 watermark instead of the desired
higher order (this was done previously by kswapd_shrink_zone(), but not
elsewhere). This false is passed for example in pgdat_balanced().
Importantly, wakeup_kswapd() uses true to make sure kswapd and thus
kcompactd are woken up for a high-order allocation failure.
The last thing is to decide what to do with pageblock_skip bitmap
handling. Compaction maintains a pageblock_skip bitmap to record
pageblocks where isolation recently failed. This bitmap can be reset by
three ways:
1) direct compaction is restarting after going through the full deferred cycle
2) kswapd goes to sleep, and some other direct compaction has previously
finished scanning the whole zone and set zone->compact_blockskip_flush.
Note that a successful direct compaction clears this flag.
3) compaction was invoked manually via trigger in /proc
The case 2) is somewhat fuzzy to begin with, but after introducing
kcompactd we should update it. The check for direct compaction in 1),
and to set the flush flag in 2) use current_is_kswapd(), which doesn't
work for kcompactd. Thus, this patch adds bool direct_compaction to
compact_control to use in 2). For the case 1) we remove the check
completely - unlike the former kswapd compaction, kcompactd does use the
deferred compaction functionality, so flushing tied to restarting from
deferred compaction makes sense here.
Note that when kswapd goes to sleep, kcompactd is woken up, so it will
see the flushed pageblock_skip bits. This is different from when the
former kswapd compaction observed the bits and I believe it makes more
sense. Kcompactd can afford to be more thorough than a direct
compaction trying to limit allocation latency, or kswapd whose primary
goal is to reclaim.
For testing, I used stress-highalloc configured to do order-9
allocations with GFP_NOWAIT|__GFP_HIGH|__GFP_COMP, so they relied just
on kswapd/kcompactd reclaim/compaction (the interfering kernel builds in
phases 1 and 2 work as usual):
stress-highalloc
4.5-rc1+before 4.5-rc1+after
-nodirect -nodirect
Success 1 Min 1.00 ( 0.00%) 5.00 (-66.67%)
Success 1 Mean 1.40 ( 0.00%) 6.20 (-55.00%)
Success 1 Max 2.00 ( 0.00%) 7.00 (-16.67%)
Success 2 Min 1.00 ( 0.00%) 5.00 (-66.67%)
Success 2 Mean 1.80 ( 0.00%) 6.40 (-52.38%)
Success 2 Max 3.00 ( 0.00%) 7.00 (-16.67%)
Success 3 Min 34.00 ( 0.00%) 62.00 ( 1.59%)
Success 3 Mean 41.80 ( 0.00%) 63.80 ( 1.24%)
Success 3 Max 53.00 ( 0.00%) 65.00 ( 2.99%)
User 3166.67 3181.09
System 1153.37 1158.25
Elapsed 1768.53 1799.37
4.5-rc1+before 4.5-rc1+after
-nodirect -nodirect
Direct pages scanned 32938 32797
Kswapd pages scanned
2183166 2202613
Kswapd pages reclaimed
2152359 2143524
Direct pages reclaimed 32735 32545
Percentage direct scans 1% 1%
THP fault alloc 579 612
THP collapse alloc 304 316
THP splits 0 0
THP fault fallback 793 778
THP collapse fail 11 16
Compaction stalls 1013 1007
Compaction success 92 67
Compaction failures 920 939
Page migrate success 238457 721374
Page migrate failure 23021 23469
Compaction pages isolated 504695
1479924
Compaction migrate scanned 661390
8812554
Compaction free scanned
13476658 84327916
Compaction cost 262 838
After this patch we see improvements in allocation success rate
(especially for phase 3) along with increased compaction activity. The
compaction stalls (direct compaction) in the interfering kernel builds
(probably THP's) also decreased somewhat thanks to kcompactd activity,
yet THP alloc successes improved a bit.
Note that elapsed and user time isn't so useful for this benchmark,
because of the background interference being unpredictable. It's just
to quickly spot some major unexpected differences. System time is
somewhat more useful and that didn't increase.
Also (after adjusting mmtests' ftrace monitor):
Time kswapd awake
2547781 2269241
Time kcompactd awake 0 119253
Time direct compacting 939937 557649
Time kswapd compacting 0 0
Time kcompactd compacting 0 119099
The decrease of overal time spent compacting appears to not match the
increased compaction stats. I suspect the tasks get rescheduled and
since the ftrace monitor doesn't see that, the reported time is wall
time, not CPU time. But arguably direct compactors care about overall
latency anyway, whether busy compacting or waiting for CPU doesn't
matter. And that latency seems to almost halved.
It's also interesting how much time kswapd spent awake just going
through all the priorities and failing to even try compacting, over and
over.
We can also configure stress-highalloc to perform both direct
reclaim/compaction and wakeup kswapd/kcompactd, by using
GFP_KERNEL|__GFP_HIGH|__GFP_COMP:
stress-highalloc
4.5-rc1+before 4.5-rc1+after
-direct -direct
Success 1 Min 4.00 ( 0.00%) 9.00 (-50.00%)
Success 1 Mean 8.00 ( 0.00%) 10.00 (-19.05%)
Success 1 Max 12.00 ( 0.00%) 11.00 ( 15.38%)
Success 2 Min 4.00 ( 0.00%) 9.00 (-50.00%)
Success 2 Mean 8.20 ( 0.00%) 10.00 (-16.28%)
Success 2 Max 13.00 ( 0.00%) 11.00 ( 8.33%)
Success 3 Min 75.00 ( 0.00%) 74.00 ( 1.33%)
Success 3 Mean 75.60 ( 0.00%) 75.20 ( 0.53%)
Success 3 Max 77.00 ( 0.00%) 76.00 ( 0.00%)
User 3344.73 3246.04
System 1194.24 1172.29
Elapsed 1838.04 1836.76
4.5-rc1+before 4.5-rc1+after
-direct -direct
Direct pages scanned 125146 120966
Kswapd pages scanned
2119757 2135012
Kswapd pages reclaimed
2073183 2108388
Direct pages reclaimed 124909 120577
Percentage direct scans 5% 5%
THP fault alloc 599 652
THP collapse alloc 323 354
THP splits 0 0
THP fault fallback 806 793
THP collapse fail 17 16
Compaction stalls 2457 2025
Compaction success 906 518
Compaction failures 1551 1507
Page migrate success
2031423 2360608
Page migrate failure 32845 40852
Compaction pages isolated
4129761 4802025
Compaction migrate scanned
11996712 21750613
Compaction free scanned
214970969 344372001
Compaction cost 2271 2694
In this scenario, this patch doesn't change the overall success rate as
direct compaction already tries all it can. There's however significant
reduction in direct compaction stalls (that is, the number of
allocations that went into direct compaction). The number of successes
(i.e. direct compaction stalls that ended up with successful
allocation) is reduced by the same number. This means the offload to
kcompactd is working as expected, and direct compaction is reduced
either due to detecting contention, or compaction deferred by kcompactd.
In the previous version of this patchset there was some apparent
reduction of success rate, but the changes in this version (such as
using sync compaction only), new baseline kernel, and/or averaging
results from 5 executions (my bet), made this go away.
Ftrace-based stats seem to roughly agree:
Time kswapd awake
2532984 2326824
Time kcompactd awake 0 257916
Time direct compacting 864839 735130
Time kswapd compacting 0 0
Time kcompactd compacting 0 257585
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Thu, 17 Mar 2016 21:18:12 +0000 (14:18 -0700)]
mm, memory hotplug: small cleanup in online_pages()
We can reuse the nid we've determined instead of repeated pfn_to_nid()
usages. Also zone_to_nid() should be a bit cheaper in general than
pfn_to_nid().
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Thu, 17 Mar 2016 21:18:08 +0000 (14:18 -0700)]
mm, compaction: introduce kcompactd
Memory compaction can be currently performed in several contexts:
- kswapd balancing a zone after a high-order allocation failure
- direct compaction to satisfy a high-order allocation, including THP
page fault attemps
- khugepaged trying to collapse a hugepage
- manually from /proc
The purpose of compaction is two-fold. The obvious purpose is to
satisfy a (pending or future) high-order allocation, and is easy to
evaluate. The other purpose is to keep overal memory fragmentation low
and help the anti-fragmentation mechanism. The success wrt the latter
purpose is more
The current situation wrt the purposes has a few drawbacks:
- compaction is invoked only when a high-order page or hugepage is not
available (or manually). This might be too late for the purposes of
keeping memory fragmentation low.
- direct compaction increases latency of allocations. Again, it would
be better if compaction was performed asynchronously to keep
fragmentation low, before the allocation itself comes.
- (a special case of the previous) the cost of compaction during THP
page faults can easily offset the benefits of THP.
- kswapd compaction appears to be complex, fragile and not working in
some scenarios. It could also end up compacting for a high-order
allocation request when it should be reclaiming memory for a later
order-0 request.
To improve the situation, we should be able to benefit from an
equivalent of kswapd, but for compaction - i.e. a background thread
which responds to fragmentation and the need for high-order allocations
(including hugepages) somewhat proactively.
One possibility is to extend the responsibilities of kswapd, which could
however complicate its design too much. It should be better to let
kswapd handle reclaim, as order-0 allocations are often more critical
than high-order ones.
Another possibility is to extend khugepaged, but this kthread is a
single instance and tied to THP configs.
This patch goes with the option of a new set of per-node kthreads called
kcompactd, and lays the foundations, without introducing any new
tunables. The lifecycle mimics kswapd kthreads, including the memory
hotplug hooks.
For compaction, kcompactd uses the standard compaction_suitable() and
ompact_finished() criteria and the deferred compaction functionality.
Unlike direct compaction, it uses only sync compaction, as there's no
allocation latency to minimize.
This patch doesn't yet add a call to wakeup_kcompactd. The kswapd
compact/reclaim loop for high-order pages will be replaced by waking up
kcompactd in the next patch with the description of what's wrong with
the old approach.
Waking up of the kcompactd threads is also tied to kswapd activity and
follows these rules:
- we don't want to affect any fastpaths, so wake up kcompactd only from
the slowpath, as it's done for kswapd
- if kswapd is doing reclaim, it's more important than compaction, so
don't invoke kcompactd until kswapd goes to sleep
- the target order used for kswapd is passed to kcompactd
Future possible future uses for kcompactd include the ability to wake up
kcompactd on demand in special situations, such as when hugepages are
not available (currently not done due to __GFP_NO_KSWAPD) or when a
fragmentation event (i.e. __rmqueue_fallback()) occurs. It's also
possible to perform periodic compaction with kcompactd.
[arnd@arndb.de: fix build errors with kcompactd]
[paul.gortmaker@windriver.com: don't use modular references for non modular code]
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Thu, 17 Mar 2016 21:18:05 +0000 (14:18 -0700)]
mm, kswapd: remove bogus check of balance_classzone_idx
During work on kcompactd integration I have spotted a confusing check of
balance_classzone_idx, which I believe is bogus.
The balanced_classzone_idx is filled by balance_pgdat() as the highest
zone it attempted to balance. This was introduced by commit
dc83edd941f4
("mm: kswapd: use the classzone idx that kswapd was using for
sleeping_prematurely()").
The intention is that (as expressed in today's function names), the
value used for kswapd_shrink_zone() calls in balance_pgdat() is the same
as for the decisions in kswapd_try_to_sleep().
An unwanted side-effect of that commit was breaking the checks in
kswapd() whether there was another kswapd_wakeup with a tighter (=lower)
classzone_idx. Commits
215ddd6664ce ("mm: vmscan: only read
new_classzone_idx from pgdat when reclaiming successfully") and
d2ebd0f6b895 ("kswapd: avoid unnecessary rebalance after an unsuccessful
balancing") tried to fixed, but apparently introduced a bogus check that
this patch removes.
Consider zone indexes X < Y < Z, where:
- Z is the value used for the first kswapd wakeup.
- Y is returned as balanced_classzone_idx, which means zones with index higher
than Y (including Z) were found to be unreclaimable.
- X is the value used for the second kswapd wakeup
The new wakeup with value X means that kswapd is now supposed to balance
harder all zones with index <= X. But instead, due to Y < Z, it will go
sleep and won't read the new value X. This is subtly wrong.
The effect of this patch is that kswapd will react better in some
situations, where e.g. the first wakeup is for ZONE_DMA32, the second is
for ZONE_DMA, and due to unreclaimable ZONE_NORMAL. Before this patch,
kswapd would go sleep instead of reclaiming ZONE_DMA harder. I expect
these situations are very rare, and more value is in better
maintainability due to the removal of confusing and bogus check.
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Thu, 17 Mar 2016 21:18:02 +0000 (14:18 -0700)]
tile: query dynamic DEBUG_PAGEALLOC setting
We can disable debug_pagealloc processing even if the code is compiled
with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query
whether it is enabled or not in runtime.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Takashi Iwai <tiwai@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Thu, 17 Mar 2016 21:17:59 +0000 (14:17 -0700)]
powerpc: query dynamic DEBUG_PAGEALLOC setting
We can disable debug_pagealloc processing even if the code is compiled
with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query
whether it is enabled or not in runtime.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Thu, 17 Mar 2016 21:17:56 +0000 (14:17 -0700)]
sound: query dynamic DEBUG_PAGEALLOC setting
We can disable debug_pagealloc processing even if the code is compiled
with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query
whether it is enabled or not in runtime.
[akpm@linux-foundation.org: export _debug_pagealloc_enabled to modules]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Thu, 17 Mar 2016 21:17:53 +0000 (14:17 -0700)]
mm/slub: query dynamic DEBUG_PAGEALLOC setting
We can disable debug_pagealloc processing even if the code is compiled
with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query
whether it is enabled or not in runtime.
[akpm@linux-foundation.org: clean up code, per Christian]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Takashi Iwai <tiwai@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Thu, 17 Mar 2016 21:17:49 +0000 (14:17 -0700)]
mm/vmalloc: query dynamic DEBUG_PAGEALLOC setting
As CONFIG_DEBUG_PAGEALLOC can be enabled/disabled via kernel parameters
we can optimize some cases by checking the enablement state.
This is follow-up work for Christian's Optimize CONFIG_DEBUG_PAGEALLOC:
https://lkml.org/lkml/2016/1/27/194
Remaining work is to make sparc to be aware of this but it looks not
easy for me so I skip that in this series.
This patch (of 5):
We can disable debug_pagealloc processing even if the code is complied
with CONFIG_DEBUG_PAGEALLOC. This patch changes the code to query
whether it is enabled or not in runtime.
[akpm@linux-foundation.org: update comment, per David. Adjust comment to use 80 cols]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Takashi Iwai <tiwai@suse.com>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Naoya Horiguchi [Thu, 17 Mar 2016 21:17:47 +0000 (14:17 -0700)]
tools/vm/page-types.c: support swap entry
/proc/pid/pagemap (pte_to_pagemap_entry() internally) already reports
about swap entry, so let's make the in-kernel utility aware of it.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Naoya Horiguchi [Thu, 17 Mar 2016 21:17:44 +0000 (14:17 -0700)]
/proc/kpageflags: return KPF_SLAB for slab tail pages
Currently /proc/kpageflags returns just KPF_COMPOUND_TAIL for slab tail
pages, which is inconvenient when grasping how slab pages are
distributed (userspace always needs to check which kind of tail pages by
itself). This patch sets KPF_SLAB for such pages.
With this patch:
$ grep Slab /proc/meminfo ; tools/vm/page-types -b slab
Slab: 64880 kB
flags page-count MB symbolic-flags long-symbolic-flags
0x0000000000000080 16220 63 _______S__________________________________ slab
total 16220 63
16220 pages equals to 64880 kB, so returned result is consistent with the
global counter.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Naoya Horiguchi [Thu, 17 Mar 2016 21:17:41 +0000 (14:17 -0700)]
/proc/kpageflags: return KPF_BUDDY for "tail" buddy pages
Currently /proc/kpageflags returns nothing for "tail" buddy pages, which
is inconvenient when grasping how free pages are distributed. This
patch sets KPF_BUDDY for such pages.
With this patch:
$ grep MemFree /proc/meminfo ; tools/vm/page-types -b buddy
MemFree:
3134992 kB
flags page-count MB symbolic-flags long-symbolic-flags
0x0000000000000400 779272 3044 __________B_______________________________ buddy
0x0000000000000c00 4385 17 __________BM______________________________ buddy,mmap
total 783657 3061
783657 pages is
3134628 kB (roughly consistent with the global counter,)
so it's OK.
[akpm@linux-foundation.org: update comment, per Naoya]
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:17:38 +0000 (14:17 -0700)]
mm: memcontrol: report kernel stack usage in cgroup2 memory.stat
Show how much memory is allocated to kernel stacks.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:17:35 +0000 (14:17 -0700)]
mm: memcontrol: report slab usage in cgroup2 memory.stat
Show how much memory is used for storing reclaimable and unreclaimable
in-kernel data structures allocated from slab caches.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:17:32 +0000 (14:17 -0700)]
mm: memcontrol: make tree_{stat,events} fetch all stats
Currently, tree_{stat,events} helpers can only get one stat index at a
time, so when there are a lot of stats to be reported one has to call it
over and over again (see memory_stat_show). This is neither effective,
nor does it look good. Instead, let's make these helpers take a
snapshot of all available counters.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vladimir Davydov [Thu, 17 Mar 2016 21:17:29 +0000 (14:17 -0700)]
mm: memcontrol: do not bypass slab charge if memcg is offline
Slab pages are charged in two steps. First, an appropriate per memcg
cache is selected (see memcg_kmem_get_cache) basing on the current
context, then the new slab page is charged to the memory cgroup which
the selected cache was created for (see memcg_charge_slab ->
__memcg_kmem_charge_memcg). It is OK to bypass kmemcg charge at step 1,
but if step 1 succeeded and we successfully allocated a new slab page,
step 2 must be performed, otherwise we would get a per memcg kmem cache
which contains a slab that does not hold a reference to the memory
cgroup owning the cache. Since per memcg kmem caches are destroyed on
memcg css free, this could result in freeing a cache while there are
still active objects in it.
However, currently we will bypass slab page charge if the memory cgroup
owning the cache is offline (see __memcg_kmem_charge_memcg). This is
very unlikely to occur in practice, because for this to happen a process
must be migrated to a different cgroup and the old cgroup must be
removed while the process is in kmalloc somewhere between steps 1 and 2
(e.g. trying to allocate a new page). Nevertheless, it's still better
to eliminate such a possibility.
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Thu, 17 Mar 2016 21:17:26 +0000 (14:17 -0700)]
mm: oom_kill: don't ignore oom score on exiting tasks
When the OOM killer scans tasks and encounters a PF_EXITING one, it
force-selects that task regardless of the score. The problem is that if
that task got stuck waiting for some state the allocation site is
holding, the OOM reaper can not move on to the next best victim.
Frankly, I don't even know why we check for exiting tasks in the OOM
killer. We've tried direct reclaim at least 15 times by the time we
decide the system is OOM, there was plenty of time to exit and free
memory; and a task might exit voluntarily right after we issue a kill.
This is testing pure noise. Remove it.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Argangeli <andrea@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joshua Hunt [Thu, 17 Mar 2016 21:17:23 +0000 (14:17 -0700)]
watchdog: don't run proc_watchdog_update if new value is same as old
While working on a script to restore all sysctl params before a series of
tests I found that writing any value into the
/proc/sys/kernel/{nmi_watchdog,soft_watchdog,watchdog,watchdog_thresh}
causes them to call proc_watchdog_update().
NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter.
NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter.
NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter.
NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter.
There doesn't appear to be a reason for doing this work every time a write
occurs, so only do it when the values change.
Signed-off-by: Josh Hunt <johunt@akamai.com>
Acked-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Ulrich Obergfell <uobergfe@redhat.com>
Cc: <stable@vger.kernel.org> [4.1.x+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Aaro Koskinen [Thu, 17 Mar 2016 21:17:20 +0000 (14:17 -0700)]
drivers/firmware/broadcom/bcm47xx_nvram.c: fix incorrect __ioread32_copy
Commit
1f330c327900 ("drivers/firmware/broadcom/bcm47xx_nvram.c: use
__ioread32_copy() instead of open-coding") switched to use a generic
copy function, but failed to notice that the header pointer is updated
between the two copies, resulting in bogus data being copied in the
latter one. Fix by keeping the old header pointer.
The patch fixes totally broken networking on WRT54GL router (both LAN and
WLAN interfaces fail to probe).
Fixes: 1f330c327900 ("drivers/firmware/broadcom/bcm47xx_nvram.c: use __ioread32_copy() instead of open-coding")
Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Rafal Milecki <zajec5@gmail.com>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: <stable@vger.kernel.org> [4.4.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Luis R. Rodriguez [Thu, 17 Mar 2016 21:17:16 +0000 (14:17 -0700)]
ia64: define ioremap_uc()
All architectures now need ioremap_uc(), ia64 seems defines this already
through its ioremap_nocache() and it already ensures it *only* uses UC.
This is needed since v4.3 to complete an allyesconfig compile on ia64,
there were others archs that needed this, and this one seems to have
fallen through the cracks.
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: <stable@vger.kernel.org> [4.3+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Thu, 17 Mar 2016 01:37:20 +0000 (18:37 -0700)]
Merge tag 'fbdev-4.6' of git://git./linux/kernel/git/tomba/linux
Pull fbdev updates from Tomi Valkeinen:
- Miscallaneous small fixes to various fbdev drivers
- Remove fb_rotate, which was never used
- pmag fb improvements
* tag 'fbdev-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tomba/linux: (21 commits)
xen kconfig: don't "select INPUT_XEN_KBDDEV_FRONTEND"
video: fbdev: sis: remove unused variable
drivers/video: make fbdev/sunxvr2500.c explicitly non-modular
drivers/video: make fbdev/sunxvr1000.c explicitly non-modular
drivers/video: make fbdev/sunxvr500.c explicitly non-modular
video: exynos: fix modular build
fbdev: da8xx-fb: fix videomodes of lcd panels
fbdev: kill fb_rotate
video: fbdev: bt431: Correct cursor format control macro
video: fbdev: pmag-ba-fb: Optimize Bt455 colormap addressing
video: fbdev: pmag-ba-fb: Fix and rework Bt455 colormap handling
video: fbdev: bt455: Remove unneeded colormap helpers for cursor support
video: fbdev: pmag-aa-fb: Report video timings
video: fbdev: pmag-aa-fb: Enable building as a module
video: fbdev: pmag-aa-fb: Adapt to current APIs
video: fbdev: pmag-ba-fb: Fix the lower margin size
fbdev: sh_mobile_lcdc: Use ARCH_RENESAS
fbdev: n411: check return value
fbdev: exynos: fix IS_ERR_VALUE usage
video: Use bool instead int pointer for get_opt_bool() argument
...
Linus Torvalds [Thu, 17 Mar 2016 01:27:32 +0000 (18:27 -0700)]
Merge tag 'media/v4.6-1' of git://git./linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:
- Added support for some new video formats
- mn88473 DVB frontend driver got promoted from staging
- several improvements at the VSP1 driver
- several cleanups and improvements at the Media Controller
- added Media Controller support to snd-usb-audio. Currently, enabled
only for au0828-based V4L2/DVB boards
- Several improvements at nuvoton-cir: it now supports wake up codes
- Add media controller support to em28xx and saa7134 drivers
- coda driver now accepts NXP distributed firmware files
- Some legacy SoC camera drivers will be moving to staging, as they're
outdated and nobody so far is willing to fix and convert them to use
the current media framework
- As usual, lots of cleanups, improvements and new board additions.
* tag 'media/v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (381 commits)
media: au0828 disable tuner to demod link in au0828_media_device_register()
[media] touptek: cast char types on %x printk
[media] touptek: don't DMA at the stack
[media] mceusb: use %*ph for small buffer dumps
[media] v4l: exynos4-is: Drop unneeded check when setting up fimc-lite links
[media] v4l: vsp1: Check if an entity is a subdev with the right function
[media] hide unused functions for !MEDIA_CONTROLLER
[media] em28xx: fix Terratec Grabby AC97 codec detection
[media] media: add prefixes to interface types
[media] media: rc: nuvoton: switch attribute wakeup_data to text
[media] v4l2-ioctl: fix YUV422P pixel format description
[media] media: fix null pointer dereference in v4l_vb2q_enable_media_source()
[media] v4l2-mc.h: fix yet more compiler errors
[media] staging/media: add missing TODO files
[media] media.h: always start with 1 for the audio entities
[media] sound/usb: Use meaninful names for goto labels
[media] v4l2-mc.h: fix compiler warnings
[media] media: au0828 audio mixer isn't connected to decoder
[media] sound/usb: Use Media Controller API to share media resources
[media] dw2102: add support for TeVii S662
...
Linus Torvalds [Thu, 17 Mar 2016 00:45:56 +0000 (17:45 -0700)]
Merge tag 'libnvdimm-for-4.6' of git://git./linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updates from Dan Williams:
- Asynchronous address range scrub:
Given the capacities of next generation persistent memory devices a
scrub operation to find all poison may take 10s of seconds. We
want this scrub work to be done asynchronously with the rest of
system initialization, so we move it out of line from the NFIT
probing, i.e. acpi_nfit_add().
- Clear poison:
ACPI 6.1 introduces the ability to send "clear error" commands to
the ACPI0012:00 device representing the root of an "nvdimm bus".
Similar to relocating a bad block on a disk, this support clears
media errors in response to a write.
- Persistent memory resource tracking:
A persistent memory range may be designated as simply "reserved" by
platform firmware in the efi/e820 memory map. Later when the NFIT
driver loads it discovers that the range is "Persistent Memory".
The NFIT bus driver inserts a resource to advertise that
"persistent" attribute in the system resource tree for /proc/iomem
and kernel-internal usages.
- Miscellaneous cleanups and fixes:
Workaround section misaligned pmem ranges when allocating a struct
page memmap, fix handling of the read-only case in the ioctl path,
and clean up block device major number allocation.
* tag 'libnvdimm-for-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (26 commits)
libnvdimm, pmem: clear poison on write
libnvdimm, pmem: fix kmap_atomic() leak in error path
nvdimm/btt: don't allocate unused major device number
nvdimm/blk: don't allocate unused major device number
pmem: don't allocate unused major device number
ACPI: Change NFIT driver to insert new resource
resource: Export insert_resource and remove_resource
resource: Add remove_resource interface
resource: Change __request_region to inherit from immediate parent
libnvdimm, pmem: fix ia64 build, use PHYS_PFN
nfit, libnvdimm: clear poison command support
libnvdimm, pfn: 'resource'-address and 'size' attributes for pfn devices
libnvdimm, pmem: adjust for section collisions with 'System RAM'
libnvdimm, pmem: fix 'pfn' support for section-misaligned namespaces
libnvdimm: Fix security issue with DSM IOCTL.
libnvdimm: Clean-up access mode check.
tools/testing/nvdimm: expand ars unit testing
nfit: disable userspace initiated ars during scrub
nfit: scrub and register regions in a workqueue
nfit, libnvdimm: async region scrub workqueue
...
Linus Torvalds [Thu, 17 Mar 2016 00:26:37 +0000 (17:26 -0700)]
Merge tag 'dm-4.6-changes' of git://git./linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- Most attention this cycle went to optimizing blk-mq request-based DM
(dm-mq) that is used exclussively by DM multipath:
- A stable fix for dm-mq that eliminates excessive context
switching offers the biggest performance improvement (for both
IOPs and throughput).
- But more work is needed, during the next cycle, to reduce
spinlock contention in DM multipath on large NUMA systems.
- A stable fix for a NULL pointer seen when DM stats is enabled on a DM
multipath device that must requeue an IO due to path failure.
- A stable fix for DM snapshot to disallow the COW and origin devices
from being identical. This amounts to graceful failure in the face
of userspace error because these devices shouldn't ever be identical.
- Stable fixes for DM cache and DM thin provisioning to address crashes
seen if/when their respective metadata device experiences failures
that cause the transition to 'fail_io' mode.
- The DM cache 'mq' policy is now an alias for the 'smq' policy. The
'smq' policy proved to be consistently better than 'mq'. As such
'mq', with all its complex user-facing tunables, has been eliminated.
- Improve DM thin provisioning to consistently return -ENOSPC once the
thin-pool's data volume is out of space.
- Improve DM core to properly handle error propagation if
bio_integrity_clone() fails in clone_bio().
- Other small cleanups and improvements to DM core.
* tag 'dm-4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (41 commits)
dm: fix rq_end_stats() NULL pointer in dm_requeue_original_request()
dm thin: consistently return -ENOSPC if pool has run out of data space
dm cache: bump the target version
dm cache: make sure every metadata function checks fail_io
dm: add missing newline between DM_DEBUG_BLOCK_STACK_TRACING and DM_BUFIO
dm cache policy smq: clarify that mq registration failure was for 'mq'
dm: return error if bio_integrity_clone() fails in clone_bio()
dm thin metadata: don't issue prefetches if a transaction abort has failed
dm snapshot: disallow the COW and origin devices from being identical
dm cache: make the 'mq' policy an alias for 'smq'
dm: drop unnecessary assignment of md->queue
dm: reorder 'struct mapped_device' members to fix alignment and holes
dm: remove dummy definition of 'struct dm_table'
dm: add 'dm_numa_node' module parameter
dm thin metadata: remove needless newline from subtree_dec() DMERR message
dm mpath: cleanup reinstate_path() et al based on code review
dm mpath: remove __pgpath_busy forward declaration, rename to pgpath_busy
dm mpath: switch from 'unsigned' to 'bool' for flags where appropriate
dm round robin: use percpu 'repeat_count' and 'current_path'
dm path selector: remove 'repeat_count' return from .select_path hook
...
Linus Torvalds [Thu, 17 Mar 2016 00:16:22 +0000 (17:16 -0700)]
Merge tag 'scsi-misc' of git://git./linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This pull includes driver updates from the usual suspects (stex, hpsa,
ncr5380, scsi_dh, qla2xxx, be2iscsi, hisi_sas, cxlflash, aacraid,
mp3sas, megaraid_sas, ibmvscsi, ufs) plus an assortment of
miscellaneous fixes.
The major user visible change of this pull is that we've moved from
monotonically increasing host number to an ida allocated one (meaning
the numbers get re-used) because someone managed to wrap the count in
an iscsi system. We don't believe there will be any adverse
consequences of this"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (230 commits)
MAINTAINERS: use new email address for James Bottomley
mpt3sas: Remove unnecessary synchronize_irq() before free_irq()
sg: fix dxferp in from_to case
cxlflash: Increase cmd_per_lun for better throughput
cxlflash: Fix to avoid unnecessary scan with internal LUNs
cxlflash: Reorder user context initialization
cxlflash: Simplify attach path error cleanup
cxlflash: Split out context initialization
cxlflash: Unmap problem state area before detaching master context
cxlflash: Simplify PCI registration
scsi: storvsc: fix SRB_STATUS_ABORTED handling
be2iscsi: set the boot_kset pointer to NULL in case of failure
sd: Fix discard granularity when LBPRZ=1
be2iscsi: Remove unnecessary synchronize_irq() before free_irq()
scsi_sysfs: call 'device_add' after attaching device handler
scsi_dh_emc: update 'access_state' field
scsi_dh_rdac: update 'access_state' field
scsi_dh_alua: update 'access_state' field
scsi_dh_alua: use common definitions for ALUA state
scsi: Add 'access_state' and 'preferred_path' attribute
...
Linus Torvalds [Thu, 17 Mar 2016 00:10:17 +0000 (17:10 -0700)]
Merge branch 'stable/for-linus-4.6' of git://git./linux/kernel/git/konrad/ibft
Pull iscsi_ibft update from Konrad Rzeszutek Wilk:
"A simple patch that had been rattling around in SuSE repo"
* 'stable/for-linus-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/ibft:
iscsi_ibft: Add prefix-len attr and display netmask
Linus Torvalds [Wed, 16 Mar 2016 21:45:55 +0000 (14:45 -0700)]
Merge tag 'pci-v4.6-changes' of git://git./linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
"PCI changes for v4.6:
Enumeration:
- Disable IO/MEM decoding for devices with non-compliant BARs (Bjorn Helgaas)
- Mark Broadwell-EP Home Agent & PCU as having non-compliant BARs (Bjorn Helgaas
Resource management:
- Mark shadow copy of VGA ROM as IORESOURCE_PCI_FIXED (Bjorn Helgaas)
- Don't assign or reassign immutable resources (Bjorn Helgaas)
- Don't enable/disable ROM BAR if we're using a RAM shadow copy (Bjorn Helgaas)
- Set ROM shadow location in arch code, not in PCI core (Bjorn Helgaas)
- Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs (Bjorn Helgaas)
- ia64: Use ioremap() instead of open-coded equivalent (Bjorn Helgaas)
- ia64: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
- MIPS: Keep CPU physical (not virtual) addresses in shadow ROM resource (Bjorn Helgaas)
- Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY (Bjorn Helgaas)
- Don't leak memory if sysfs_create_bin_file() fails (Bjorn Helgaas)
- rcar: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
- designware: Remove PCI_PROBE_ONLY handling (Lorenzo Pieralisi)
Virtualization:
- Wait for up to 1000ms after FLR reset (Alex Williamson)
- Support SR-IOV on any function type (Kelly Zytaruk)
- Add ACS quirk for all Cavium devices (Manish Jaggi)
AER:
- Rename pci_ops_aer to aer_inj_pci_ops (Bjorn Helgaas)
- Restore pci_ops pointer while calling original pci_ops (David Daney)
- Fix aer_inject error codes (Jean Delvare)
- Use dev_warn() in aer_inject (Jean Delvare)
- Log actual error causes in aer_inject (Jean Delvare)
- Log aer_inject error injections (Jean Delvare)
VPD:
- Prevent VPD access for buggy devices (Babu Moger)
- Move pci_read_vpd() and pci_write_vpd() close to other VPD code (Bjorn Helgaas)
- Move pci_vpd_release() from header file to pci/access.c (Bjorn Helgaas)
- Remove struct pci_vpd_ops.release function pointer (Bjorn Helgaas)
- Rename VPD symbols to remove unnecessary "pci22" (Bjorn Helgaas)
- Fold struct pci_vpd_pci22 into struct pci_vpd (Bjorn Helgaas)
- Sleep rather than busy-wait for VPD access completion (Bjorn Helgaas)
- Update VPD definitions (Hannes Reinecke)
- Allow access to VPD attributes with size 0 (Hannes Reinecke)
- Determine actual VPD size on first access (Hannes Reinecke)
Generic host bridge driver:
- Move structure definitions to separate header file (David Daney)
- Add pci_host_common_probe(), based on gen_pci_probe() (David Daney)
- Expose pci_host_common_probe() for use by other drivers (David Daney)
Altera host bridge driver:
- Fix altera_pcie_link_is_up() (Ley Foon Tan)
Cavium ThunderX host bridge driver:
- Add PCIe host driver for ThunderX processors (David Daney)
- Add driver for ThunderX-pass{1,2} on-chip devices (David Daney)
Freescale i.MX6 host bridge driver:
- Add DT bindings to configure PHY Tx driver settings (Justin Waters)
- Move imx6_pcie_reset_phy() near other PHY handling functions (Lucas Stach)
- Move PHY reset into imx6_pcie_establish_link() (Lucas Stach)
- Remove broken Gen2 workaround (Lucas Stach)
- Move link up check into imx6_pcie_wait_for_link() (Lucas Stach)
Freescale Layerscape host bridge driver:
- Add "fsl,ls2085a-pcie" compatible ID (Yang Shi)
Intel VMD host bridge driver:
- Attach VMD resources to parent domain's resource tree (Jon Derrick)
- Set bus resource start to 0 (Keith Busch)
Microsoft Hyper-V host bridge driver:
- Add fwnode_handle to x86 pci_sysdata (Jake Oshins)
- Look up IRQ domain by fwnode_handle (Jake Oshins)
- Add paravirtual PCI front-end for Microsoft Hyper-V VMs (Jake Oshins)
NVIDIA Tegra host bridge driver:
- Add pci_ops.{add,remove}_bus() callbacks (Thierry Reding)
- Implement ->{add,remove}_bus() callbacks (Thierry Reding)
- Remove unused struct tegra_pcie.num_ports field (Thierry Reding)
- Track bus -> CPU mapping (Thierry Reding)
- Remove misleading PHYS_OFFSET (Thierry Reding)
Renesas R-Car host bridge driver:
- Depend on ARCH_RENESAS, not ARCH_SHMOBILE (Simon Horman)
Synopsys DesignWare host bridge driver:
- ARC: Add PCI support (Joao Pinto)
- Add generic dw_pcie_wait_for_link() (Joao Pinto)
- Add default link up check if sub-driver doesn't override (Joao Pinto)
- Add driver for prototyping kits based on ARC SDP (Joao Pinto)
TI Keystone host bridge driver:
- Defer probing if devm_phy_get() returns -EPROBE_DEFER (Shawn Lin)
Xilinx AXI host bridge driver:
- Use of_pci_get_host_bridge_resources() to parse DT (Bharat Kumar Gogada)
- Remove dependency on ARM-specific struct hw_pci (Bharat Kumar Gogada)
- Don't call pci_fixup_irqs() on Microblaze (Bharat Kumar Gogada)
- Update Zynq binding with Microblaze node (Bharat Kumar Gogada)
- microblaze: Support generic Xilinx AXI PCIe Host Bridge IP driver (Bharat Kumar Gogada)
Xilinx NWL host bridge driver:
- Add support for Xilinx NWL PCIe Host Controller (Bharat Kumar Gogada)
Miscellaneous:
- Check device_attach() return value always (Bjorn Helgaas)
- Move pci_set_flags() from asm-generic/pci-bridge.h to linux/pci.h (Bjorn Helgaas)
- Remove includes of empty asm-generic/pci-bridge.h (Bjorn Helgaas)
- ARM64: Remove generated include of asm-generic/pci-bridge.h (Bjorn Helgaas)
- Remove empty asm-generic/pci-bridge.h (Bjorn Helgaas)
- Remove includes of asm/pci-bridge.h (Bjorn Helgaas)
- Consolidate PCI DMA constants and interfaces in linux/pci-dma-compat.h (Bjorn Helgaas)
- unicore32: Remove unused HAVE_ARCH_PCI_SET_DMA_MASK definition (Bjorn Helgaas)
- Cleanup pci/pcie/Kconfig whitespace (Andreas Ziegler)
- Include pci/hotplug Kconfig directly from pci/Kconfig (Bjorn Helgaas)
- Include pci/pcie/Kconfig directly from pci/Kconfig (Bogicevic Sasa)
- frv: Remove stray pci_{alloc,free}_consistent() declaration (Christoph Hellwig)
- Move pci_dma_* helpers to common code (Christoph Hellwig)
- Add PCI_CLASS_SERIAL_USB_DEVICE definition (Heikki Krogerus)
- Add QEMU top-level IDs for (sub)vendor & device (Robin H. Johnson)
- Fix broken URL for Dell biosdevname (Naga Venkata Sai Indubhaskar Jupudi)"
* tag 'pci-v4.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (94 commits)
PCI: Add PCI_CLASS_SERIAL_USB_DEVICE definition
PCI: designware: Add driver for prototyping kits based on ARC SDP
PCI: designware: Add default link up check if sub-driver doesn't override
PCI: designware: Add generic dw_pcie_wait_for_link()
PCI: Cleanup pci/pcie/Kconfig whitespace
PCI: Simplify pci_create_attr() control flow
PCI: Don't leak memory if sysfs_create_bin_file() fails
PCI: Simplify sysfs ROM cleanup
PCI: Remove unused IORESOURCE_ROM_COPY and IORESOURCE_ROM_BIOS_COPY
MIPS: Loongson 3: Keep CPU physical (not virtual) addresses in shadow ROM resource
MIPS: Loongson 3: Use temporary struct resource * to avoid repetition
ia64/PCI: Keep CPU physical (not virtual) addresses in shadow ROM resource
ia64/PCI: Use ioremap() instead of open-coded equivalent
ia64/PCI: Use temporary struct resource * to avoid repetition
PCI: Clean up pci_map_rom() whitespace
PCI: Remove arch-specific IORESOURCE_ROM_SHADOW size from sysfs
PCI: thunder: Add driver for ThunderX-pass{1,2} on-chip devices
PCI: thunder: Add PCIe host driver for ThunderX processors
PCI: generic: Expose pci_host_common_probe() for use by other drivers
PCI: generic: Add pci_host_common_probe(), based on gen_pci_probe()
...
Linus Torvalds [Wed, 16 Mar 2016 21:10:53 +0000 (14:10 -0700)]
Merge tag 'pm+acpi-4.6-rc1-1' of git://git./linux/kernel/git/rafael/linux-pm
Pull power management and ACPI updates from Rafael Wysocki:
"This time the majority of changes go into cpufreq and they are
significant.
First off, the way CPU frequency updates are triggered is different
now. Instead of having to set up and manage a deferrable timer for
each CPU in the system to evaluate and possibly change its frequency
periodically, cpufreq governors set up callbacks to be invoked by the
scheduler on a regular basis (basically on utilization updates). The
"old" governors, "ondemand" and "conservative", still do all of their
work in process context (although that is triggered by the scheduler
now), but intel_pstate does it all in the callback invoked by the
scheduler with no need for any additional asynchronous processing.
Of course, this eliminates the overhead related to the management of
all those timers, but also it allows the cpufreq governor code to be
simplified quite a bit. On top of that, the common code and data
structures used by the "ondemand" and "conservative" governors are
cleaned up and made more straightforward and some long-standing and
quite annoying problems are addressed. In particular, the handling of
governor sysfs attributes is modified and the related locking becomes
more fine grained which allows some concurrency problems to be avoided
(particularly deadlocks with the core cpufreq code).
In principle, the new mechanism for triggering frequency updates
allows utilization information to be passed from the scheduler to
cpufreq. Although the current code doesn't make use of it, in the
works is a new cpufreq governor that will make decisions based on the
scheduler's utilization data. That should allow the scheduler and
cpufreq to work more closely together in the long run.
In addition to the core and governor changes, cpufreq drivers are
updated too. Fixes and optimizations go into intel_pstate, the
cpufreq-dt driver is updated on top of some modification in the
Operating Performance Points (OPP) framework and there are fixes and
other updates in the powernv cpufreq driver.
Apart from the cpufreq updates there is some new ACPICA material,
including a fix for a problem introduced by previous ACPICA updates,
and some less significant changes in the ACPI code, like CPPC code
optimizations, ACPI processor driver cleanups and support for loading
ACPI tables from initrd.
Also updated are the generic power domains framework, the Intel RAPL
power capping driver and the turbostat utility and we have a bunch of
traditional assorted fixes and cleanups.
Specifics:
- Redesign of cpufreq governors and the intel_pstate driver to make
them use callbacks invoked by the scheduler to trigger CPU
frequency evaluation instead of using per-CPU deferrable timers for
that purpose (Rafael Wysocki).
- Reorganization and cleanup of cpufreq governor code to make it more
straightforward and fix some concurrency problems in it (Rafael
Wysocki, Viresh Kumar).
- Cleanup and improvements of locking in the cpufreq core (Viresh
Kumar).
- Assorted cleanups in the cpufreq core (Rafael Wysocki, Viresh
Kumar, Eric Biggers).
- intel_pstate driver updates including fixes, optimizations and a
modification to make it enable enable hardware-coordinated P-state
selection (HWP) by default if supported by the processor (Philippe
Longepe, Srinivas Pandruvada, Rafael Wysocki, Viresh Kumar, Felipe
Franciosi).
- Operating Performance Points (OPP) framework updates to improve its
handling of voltage regulators and device clocks and updates of the
cpufreq-dt driver on top of that (Viresh Kumar, Jon Hunter).
- Updates of the powernv cpufreq driver to fix initialization and
cleanup problems in it and correct its worker thread handling with
respect to CPU offline, new powernv_throttle tracepoint (Shilpasri
Bhat).
- ACPI cpufreq driver optimization and cleanup (Rafael Wysocki).
- ACPICA updates including one fix for a regression introduced by
previos changes in the ACPICA code (Bob Moore, Lv Zheng, David Box,
Colin Ian King).
- Support for installing ACPI tables from initrd (Lv Zheng).
- Optimizations of the ACPI CPPC code (Prashanth Prakash, Ashwin
Chaugule).
- Support for _HID(ACPI0010) devices (ACPI processor containers) and
ACPI processor driver cleanups (Sudeep Holla).
- Support for ACPI-based enumeration of the AMBA bus (Graeme Gregory,
Aleksey Makarov).
- Modification of the ACPI PCI IRQ management code to make it treat
255 in the Interrupt Line register as "not connected" on x86 (as
per the specification) and avoid attempts to use that value as a
valid interrupt vector (Chen Fan).
- ACPI APEI fixes related to resource leaks (Josh Hunt).
- Removal of modularity from a few ACPI drivers (BGRT, GHES,
intel_pmic_crc) that cannot be built as modules in practice (Paul
Gortmaker).
- PNP framework update to make it treat ACPI_RESOURCE_TYPE_SERIAL_BUS
as a valid resource type (Harb Abdulhamid).
- New device ID (future AMD I2C controller) in the ACPI driver for
AMD SoCs (APD) and in the designware I2C driver (Xiangliang Yu).
- Assorted ACPI cleanups (Colin Ian King, Kaiyen Chang, Oleg Drokin).
- cpuidle menu governor optimization to avoid a square root
computation in it (Rasmus Villemoes).
- Fix for potential use-after-free in the generic device properties
framework (Heikki Krogerus).
- Updates of the generic power domains (genpd) framework including
support for multiple power states of a domain, fixes and debugfs
output improvements (Axel Haslam, Jon Hunter, Laurent Pinchart,
Geert Uytterhoeven).
- Intel RAPL power capping driver updates to reduce IPI overhead in
it (Jacob Pan).
- System suspend/hibernation code cleanups (Eric Biggers, Saurabh
Sengar).
- Year 2038 fix for the process freezer (Abhilash Jindal).
- turbostat utility updates including new features (decoding of more
registers and CPUID fields, sub-second intervals support, GFX MHz
and RC6 printout, --out command line option), fixes (syscall jitter
detection and workaround, reductioin of the number of syscalls
made, fixes related to Xeon x200 processors, compiler warning
fixes) and cleanups (Len Brown, Hubert Chrzaniuk, Chen Yu)"
* tag 'pm+acpi-4.6-rc1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (182 commits)
tools/power turbostat: bugfix: TDP MSRs print bits fixing
tools/power turbostat: correct output for MSR_NHM_SNB_PKG_CST_CFG_CTL dump
tools/power turbostat: call __cpuid() instead of __get_cpuid()
tools/power turbostat: indicate SMX and SGX support
tools/power turbostat: detect and work around syscall jitter
tools/power turbostat: show GFX%rc6
tools/power turbostat: show GFXMHz
tools/power turbostat: show IRQs per CPU
tools/power turbostat: make fewer systems calls
tools/power turbostat: fix compiler warnings
tools/power turbostat: add --out option for saving output in a file
tools/power turbostat: re-name "%Busy" field to "Busy%"
tools/power turbostat: Intel Xeon x200: fix turbo-ratio decoding
tools/power turbostat: Intel Xeon x200: fix erroneous bclk value
tools/power turbostat: allow sub-sec intervals
ACPI / APEI: ERST: Fixed leaked resources in erst_init
ACPI / APEI: Fix leaked resources
intel_pstate: Do not skip samples partially
intel_pstate: Remove freq calculation from intel_pstate_calc_busy()
intel_pstate: Move intel_pstate_calc_busy() into get_target_pstate_use_performance()
...
Linus Torvalds [Wed, 16 Mar 2016 18:51:08 +0000 (11:51 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge first patch-bomb from Andrew Morton:
- some misc things
- ofs2 updates
- about half of MM
- checkpatch updates
- autofs4 update
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits)
autofs4: fix string.h include in auto_dev-ioctl.h
autofs4: use pr_xxx() macros directly for logging
autofs4: change log print macros to not insert newline
autofs4: make autofs log prints consistent
autofs4: fix some white space errors
autofs4: fix invalid ioctl return in autofs4_root_ioctl_unlocked()
autofs4: fix coding style line length in autofs4_wait()
autofs4: fix coding style problem in autofs4_get_set_timeout()
autofs4: coding style fixes
autofs: show pipe inode in mount options
kallsyms: add support for relative offsets in kallsyms address table
kallsyms: don't overload absolute symbol type for percpu symbols
x86: kallsyms: disable absolute percpu symbols on !SMP
checkpatch: fix another left brace warning
checkpatch: improve UNSPECIFIED_INT test for bare signed/unsigned uses
checkpatch: warn on bare unsigned or signed declarations without int
checkpatch: exclude asm volatile from complex macro check
mm: memcontrol: drop unnecessary lru locking from mem_cgroup_migrate()
mm: migrate: consolidate mem_cgroup_migrate() calls
mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous
...
Linus Torvalds [Wed, 16 Mar 2016 17:53:26 +0000 (10:53 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/geert/linux-m68k
Pull m68k updates from Geert Uytterhoeven.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
m68k: Fix misspellings in comments.
m68k: Use conventional function parameters for do_sigreturn
zorro: Use kobj_to_dev()
Linus Torvalds [Wed, 16 Mar 2016 17:47:45 +0000 (10:47 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
- Add the CPU id for the new z13s machine
- Add a s390 specific XOR template for RAID-5 checksumming based on the
XC instruction. Remove all other alternatives, XC is always faster
- The merge of our four different stack tracers into a single one
- Tidy up the code related to page tables, several large inline
functions are now out-of-line. Bloat-o-meter reports ~11K text size
reduction
- A binary interface for the priviledged CLP instruction to retrieve
the hardware view of the installed PCI functions
- Improvements for the dasd format code
- Bug fixes and cleanups
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (31 commits)
s390/pci: enforce fmb page boundary rule
s390: fix floating pointer register corruption (again)
s390/cpumf: add missing lpp magic initialization
s390: Fix misspellings in comments
s390/mm: split arch/s390/mm/pgtable.c
s390/mm: uninline pmdp_xxx functions from pgtable.h
s390/mm: uninline ptep_xxx functions from pgtable.h
s390/pci: add ioctl interface for CLP
s390: Use pr_warn instead of pr_warning
s390/dasd: remove casts to dasd_*_private
s390/dasd: Refactor dasd format functions
s390/dasd: Simplify code in format logic
s390/dasd: Improve dasd format code
s390/percpu: remove this_cpu_cmpxchg_double_4
s390/cpumf: Improve guest detection heuristics
s390/fault: merge report_user_fault implementations
s390/dis: use correct escape sequence for '%' character
s390/kvm: simplify set_guest_storage_key
s390/oprofile: add z13/z13s model numbers
s390: add z13s model number to z13 elf platform
...
Linus Torvalds [Wed, 16 Mar 2016 17:09:30 +0000 (10:09 -0700)]
Merge branch 'for-linus' of git://git./linux/kernel/git/egtvedt/linux-avr32
Pull AVR32 updates from Hans-Christian Egtvedt.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/egtvedt/linux-avr32:
avr32: fix asm operand constraint in cmpxchg()
avr32: wire up copy_file_range syscall
Linus Torvalds [Wed, 16 Mar 2016 16:55:35 +0000 (09:55 -0700)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"One of the largest releases for KVM... Hardly any generic
changes, but lots of architecture-specific updates.
ARM:
- VHE support so that we can run the kernel at EL2 on ARMv8.1 systems
- PMU support for guests
- 32bit world switch rewritten in C
- various optimizations to the vgic save/restore code.
PPC:
- enabled KVM-VFIO integration ("VFIO device")
- optimizations to speed up IPIs between vcpus
- in-kernel handling of IOMMU hypercalls
- support for dynamic DMA windows (DDW).
s390:
- provide the floating point registers via sync regs;
- separated instruction vs. data accesses
- dirty log improvements for huge guests
- bugfixes and documentation improvements.
x86:
- Hyper-V VMBus hypercall userspace exit
- alternative implementation of lowest-priority interrupts using
vector hashing (for better VT-d posted interrupt support)
- fixed guest debugging with nested virtualizations
- improved interrupt tracking in the in-kernel IOAPIC
- generic infrastructure for tracking writes to guest
memory - currently its only use is to speedup the legacy shadow
paging (pre-EPT) case, but in the future it will be used for
virtual GPUs as well
- much cleanup (LAPIC, kvmclock, MMU, PIT), including ubsan fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (217 commits)
KVM: x86: remove eager_fpu field of struct kvm_vcpu_arch
KVM: x86: disable MPX if host did not enable MPX XSAVE features
arm64: KVM: vgic-v3: Only wipe LRs on vcpu exit
arm64: KVM: vgic-v3: Reset LRs at boot time
arm64: KVM: vgic-v3: Do not save an LR known to be empty
arm64: KVM: vgic-v3: Save maintenance interrupt state only if required
arm64: KVM: vgic-v3: Avoid accessing ICH registers
KVM: arm/arm64: vgic-v2: Make GICD_SGIR quicker to hit
KVM: arm/arm64: vgic-v2: Only wipe LRs on vcpu exit
KVM: arm/arm64: vgic-v2: Reset LRs at boot time
KVM: arm/arm64: vgic-v2: Do not save an LR known to be empty
KVM: arm/arm64: vgic-v2: Move GICH_ELRSR saving to its own function
KVM: arm/arm64: vgic-v2: Save maintenance interrupt state only if required
KVM: arm/arm64: vgic-v2: Avoid accessing GICH registers
KVM: s390: allocate only one DMA page per VM
KVM: s390: enable STFLE interpretation only if enabled for the guest
KVM: s390: wake up when the VCPU cpu timer expires
KVM: s390: step the VCPU timer while in enabled wait
KVM: s390: protect VCPU cpu timer with a seqcount
KVM: s390: step VCPU cpu timer during kvm_run ioctl
...
Linus Torvalds [Wed, 16 Mar 2016 15:36:55 +0000 (08:36 -0700)]
Merge tag 'edac_for_4.6' of git://git./linux/kernel/git/bp/bp
Pull EDAC updates from Borislav Petkov:
- Altera: L2 cache and On-Chip RAM support (Thor Thayer).
- EDAC: Workqueue handling cleanups (Borislav Petkov).
- Xgene: Register bus error handling (Loc Ho).
- Misc small fixes.
* tag 'edac_for_4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp:
ARM: socfpga: Enable OCRAM ECC on startup
ARM: socfpga: Enable L2 cache ECC on startup
ARM: dts: Add Altera L2 Cache and OCRAM EDAC entries
EDAC, altera: Add Altera L2 cache and OCRAM support
EDAC: Use edac_debugfs_remove_recursive() in edac_debugfs_exit()
EDAC, mpc85xx: Silence unused variable warning
EDAC: Cleanup/sync workqueue functions
EDAC: Kill workqueue setup/teardown functions
EDAC: Balance workqueue setup and teardown
arm64: Update the APM X-Gene EDAC node with the RB register resource
EDAC, xgene: Add missing SoC register bus error handling
Documentation, EDAC: Update xgene binding for missing register bus
EDAC, amd64_edac: Shift wrapping issue in f1x_get_norm_dct_addr()
Linus Torvalds [Wed, 16 Mar 2016 05:04:53 +0000 (22:04 -0700)]
Merge tag 'leds_for_4.6' of git://git./linux/kernel/git/j.anaszewski/linux-leds
Pull LED updates from Jacek Anaszewski:
"LED core improvements:
- Fix misleading comment after workqueue removal from drivers
- Avoid error message when a USB LED device is unplugged
- Add helpers for calling brightness_set(_blocking)
LED triggers:
- Simplify led_trigger_store by using sysfs_streq()
LED class drivers improvements:
- Improve wording and formatting in a comment: lp3944
- Fix return value check in create_gpio_led(): leds-gpio
- Use GPIOF_OUT_INIT_LOW instead of hardcoded zero: leds-gpio
- Use devm_led_classdev_register(): leds-lm3533, leds-lm3533,
leds-lp8788, leds-wm831x-status, leds-s3c24xx, leds-s3c24xx,
leds-max8997.
New LED class driver:
- Add driver for the ISSI IS31FL32xx family of LED controllers.
Device Tree documentation:
- of: Add vendor prefixes for Integrated Silicon Solutions Inc.
(issi) and Si-En Technology (si-en).
- DT: Add common bindings for Si-En Technology SN3216/18 and
IS31FL32xx family of LED controllers, since they seem to be the
same hardware, just rebranded"
* tag 'leds_for_4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
leds: triggers: simplify led_trigger_store
leds: max8997: Use devm_led_classdev_register
leds: da903x: Use devm_led_classdev_register
leds: s3c24xx: Use devm_led_classdev_register
leds: wm831x-status: Use devm_led_classdev_register
leds: lp8788: Use devm_led_classdev_register
leds: 88pm860x: Use devm_led_classdev_register
leds: Add SN3218 and SN3216 support to the IS31FL32XX driver
of: Add vendor prefix for Si-En Technology
leds: Add driver for the ISSI IS31FL32xx family of LED controllers
DT: leds: Add binding for the ISSI IS31FL32xx family of LED controllers
DT: Add vendor prefix for Integrated Silicon Solutions Inc.
leds: lm3533: Use devm_led_classdev_register
leds: gpio: Use GPIOF_OUT_INIT_LOW instead of hardcoded zero
leds: core: add helpers for calling brightness_set(_blocking)
leds: leds-gpio: Fix return value check in create_gpio_led()
leds: lp3944: improve wording and formatting in a comment
leds: core: avoid error message when a USB LED device is unplugged
leds: core: fix misleading comment after workqueue removal from drivers
Linus Torvalds [Wed, 16 Mar 2016 04:58:58 +0000 (21:58 -0700)]
Merge tag 'rtc-4.6' of git://git./linux/kernel/git/abelloni/linux
Pull RTC updates from Alexandre Belloni:
"Core:
- New sysfs interface to set and read clock offset
- Drivers can now be both I2C and SPI (see pcf2127 and ds3232)
New drivers:
- Alphascale ASM9260
- Epson RX6110SA
- Maxim max20024 and max77620 (in max77686)
- Microchip PIC32
- NXP pcf2129 (in pcf2127)
Subsystem wide cleanups:
- remove IRQF_EARLY_RESUME when unecessary
Drivers:
- ds1307: clock output, temperature sensor and wakeup-source support
- ds1685: actually spin forever in poweroff error path
- ds3232: many cleanups
- ds3234: merged in ds3232
- hym8563: fix invalid year calculation
- max77686: many cleanups
- max77802 merged in max77686
- pcf2123: cleanups and offset support
- pcf85063: cleanups
- pcf8523: propely handle oscillator stop bit
- rv3029: many cleanups, trickle charger and temperature sensor support
- rv8803: convert spin_lock to mutex_lock
- rx8025: many fixes
- vr41xx: restore alarm_irq_enable"
* tag 'rtc-4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (86 commits)
rtc: pcf2127: add pcf2129 device id
rtc: pcf2127: add support for spi interface
rtc: pcf2127: convert to use regmap
rtc: rv3029: Add thermometer hwmon support
rtc: rv3029: Add update_bits helper for eeprom access
rtc: ds1685: actually spin forever in poweroff error path
rtc: hym8563: fix invalid year calculation
rtc: ds3232: use rtc->ops_lock to protect alarm operations
rtc: ds3232: fix issue when irq is shared several devices
rtc: ds3232: remove unused UIE code
rtc: ds3232: add register access error checks
rtc: ds3232: fix read on /dev/rtc after RTC_AIE_ON
rtc: merge ds3232 and ds3234
rtc: ds3232: convert to use regmap
rtc: pxa: fix Kconfig indentation
rtc: rv3029: Add device tree property for trickle charger
rtc: rv3029: Add functions for EEPROM access
rtc: rv3029: Add i2c register update-bits helper
rtc: rv3029: Add missing register definitions
rtc: rv3029: Add "rv3029" I2C device id
...
Linus Torvalds [Wed, 16 Mar 2016 04:44:47 +0000 (21:44 -0700)]
Merge tag 'hwmon-for-linus-v4.6' of git://git./linux/kernel/git/groeck/linux-staging
Pull hwmon updates from Guenter Roeck:
- New drivers for NSA320 and LTC2990
- Added support for ADM1278 to adm1275 driver
- Added support for ncpXXxh103 to ntc_thermistor driver
- Renamed vexpress hwmon implementation
- Minor cleanups and improvements
* tag 'hwmon-for-linus-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: Create an NSA320 hardware monitoring driver
hwmon: Define binding for the nsa320-hwmon driver
hwmon: (adm1275) Add support for ADM1278
hwmon: (ntc_thermistor) Add support for ncpXXxh103
Doc: hwmon: Fix typo "montoring" in hwmon
ARM: dts: vfxxx: Add iio_hwmon node for ADC temperature channel
ARM: dts: Change iio_hwmon nodes to use hypen in node names
hwmon: (iio_hwmon) Allow the driver to accept hypen in device tree node names
hwmon: Add LTC2990 sensor driver
hwmon: (vexpress) rename vexpress hwmon implementation
Linus Torvalds [Wed, 16 Mar 2016 04:34:35 +0000 (21:34 -0700)]
Merge tag 'regulator-v4.6' of git://git./linux/kernel/git/broonie/regulator
Pull regulator updates from Mark Brown:
"This has been an extremely quiet release for the regulator API, aside
from bugfixes and small enhancements the only thing that really stands
out are the new drivers for Action Semiconductors ACT8945A, HiSilicon
HI665x, and the Maxim MAX20024 and MAX77620"
* tag 'regulator-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (46 commits)
regulator: pwm: Add support to have multiple instance of pwm regulator
regulator: pwm: Fix calculation of voltage-to-duty cycle
regulator: of: Use of_property_read_u32() for reading min/max
regulator: pv88060: fix incorrect clear of event register
regulator: pv88090: fix incorrect clear of event register
regulator: max77620: Add support to configure active-discharge
regulator: core: Add support for active-discharge configuration
regulator: helper: Add helper to configure active-discharge using regmap
regulator: core: Add support for active-discharge configuration
regulator: DT: Add DT property for active-discharge configuration
regulator: act8865: Specify fixed voltage of 3.3V for ACT8600's REG9
regulator: act8865: Rename platform_data field to init_data
regulator: act8865: Remove "static" from local variable
ASoC: cs4271: add regulator consumer support
regulator: max77620: Remove duplicate module alias
regulator: max77620: Eliminate duplicate code
regulator: max77620: Remove unused fields
regulator: core: fix crash in error path of regulator_register
regulator: core: Request GPIO before creating sysfs entries
regulator: gpio: don't print error on EPROBE_DEFER
...
Linus Torvalds [Wed, 16 Mar 2016 04:22:26 +0000 (21:22 -0700)]
Merge tag 'regmap-v4.6' of git://git./linux/kernel/git/broonie/regmap
Pull regmap updates from Mark Brown:
"This has been a very busy release for regmap, not just in cleaning up
the mess we got ourselves into with the endianness handling but also
in other areas too:
- Fixes for the endianness handling so that we now explicitly default
to little endian (the code used to do this by accident). This
fixes handling of explictly specified endianness on big endian
systems.
- Optimisation of the implementation of register striding.
- A refectoring of the _update_bits() code to reduce duplication.
- Fixes and enhancements for the interrupt implementation which make
it easier to use in a wider range of systems"
* tag 'regmap-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap: (28 commits)
regmap: irq: add devm apis for regmap_{add,del}_irq_chip
regmap: replace regmap_write_bits()
regmap: irq: Enable irq retriggering for nested irqs
regmap: add regmap_fields_force_xxx() macros
regmap: add regmap_field_force_xxx() macros
regmap: merge regmap_fields_update_bits() into macro
regmap: merge regmap_fields_write() into macro
regmap: add regmap_fields_update_bits_base()
regmap: merge regmap_field_update_bits() into macro
regmap: merge regmap_field_write() into macro
regmap: add regmap_field_update_bits_base()
regmap: merge regmap_update_bits_check_async() into macro
regmap: merge regmap_update_bits_check() into macro
regmap: merge regmap_update_bits_async() into macro
regmap: merge regmap_update_bits() into macro
regmap: add regmap_update_bits_base()
regcache: flat: Introduce register strider order
regcache: Introduce the index parsing API by stride order
regmap: core: Introduce register stride order
regmap: irq: add devm apis for regmap_{add,del}_irq_chip
...
Linus Torvalds [Wed, 16 Mar 2016 04:07:33 +0000 (21:07 -0700)]
Merge tag 'spi-v4.6' of git://git./linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown:
"Not the biggest set of changes for SPI but a bit of a pickup in
activity on the core:
- Support for memory mapped read from flash devices via a SPI
controller.
- The beginnings of a message rewriting framework in the core which
should in time allow us to support transforming messages to work
around the limits of controllers or optimise the performance for
controllers transparently to calling drivers.
- Updates to the PXA2xx, the main functional change being to improve
the ACPI support.
- A new driver for the Analog Devices AXI SPI engine"
* tag 'spi-v4.6' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (66 commits)
spi: Add gfp parameter to kernel-doc to fix build warning
spi: Fix htmldocs build error due struct spi_replaced_transfers
spi: rockchip: covert rsd_nsecs to u32 type
spi: rockchip: header file cleanup
spi: xilinx: Add devicetree binding for spi-xilinx
spi: respect the maximum segment size of DMA device
spi: rockchip: check requesting dma channel with EPROBE_DEFER
spi: rockchip: migrate to dmaengine_terminate_async
spi: rockchip: check return value of dmaengine_prep_slave_sg
spi: core: Fix deadlock when sending messages
spi/rockchip: fix endian mode for 16-bit transfers
spi/rockchip: Make sure spi clk is on in rockchip_spi_set_cs
spi: pxa2xx: Use newer more explicit DMAengine terminate API
spi: pxa2xx: Add support for Intel Broxton B-Step
spi: lp-8841: return correct error code from probe
spi: imx: drop bogus tests for rx/tx bufs in DMA transfer
spi: imx: set MX51_ECSPI_CTRL_SMC bit in setup function
spi: imx: make some register defines simpler
spi: imx: remove unnecessary bit clearing in mx51_ecspi_config
spi: imx: add support for all SPI word width for DMA
...
Linus Torvalds [Wed, 16 Mar 2016 03:23:13 +0000 (20:23 -0700)]
Merge tag 'pinctrl-v4.6-1' of git://git./linux/kernel/git/linusw/linux-pinctrl
Pull pin control updates from Linus Walleij:
"An almost purely driver related set of changes with no major changes
to the framework, only one patch adding an unlocked version of the
pinctrl_find_gpio_range_from_pin() library call.
New drivers:
- ST Microelectronics STM32 MCU support: this is a non-MMU low-end
platform for IoT things (etc).
- Microchip PIC32 MCU support: same story as for STM32.
New subdrivers:
- Allwinner SunXi H3 R_PIO controller support.
- Qualcomm IPQ4019 support.
- MediaTek MT2701 and MT7623.
- Allwinner A64
Non-critical fixes:
- gpio_disable_free() for the Vybrid.
- pinctrl single: use a separate lockdep class.
Misc:
- Substantial cleanups and rewrites for the Super-H PFC driver and
subdrivers.
- Various fixes and cleanups, especially Paul Gortmakers work to make
nonmodular drivers nonmodular"
* tag 'pinctrl-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (75 commits)
pinctrl: single: Use a separate lockdep class
drivers: pinctrl: add driver for Allwinner A64 SoC
pinctrl: Broadcom Northstar2 pinctrl device tree bindings
pinctrl: amlogic: Make driver independent from two-domain configuration
pinctrl: amlogic: Separate some pin functions for Meson8 / Meson8b
pinctrl: at91: use __maybe_unused to hide pm functions
pinctrl: sh-pfc: core: don't open code of_device_get_match_data()
pinctrl: uniphier: rename CONFIG options and file names
pinctrl: sunxi: make A80 explicitly non-modular
pinctrl: stm32: make explicitly non-modular
pinctrl: sh-pfc: make explicitly non-modular
pinctrl: meson: make explicitly non-modular
pinctrl: pinctrl-mt6397 driver explicitly non-modular
pinctrl: sunxi: does not need module.h
pinctrl: pxa2xx: export symbols
pinctrl: sunxi: Change mux setting on PI irq pins
pinctrl: sunxi: Remove non existing irq's
pinctrl: imx: attach iomuxc device to gpr syscon
pinctrl-bcm2835: Fix cut-and-paste error in "pull" parsing
pinctrl: lpc1850-scu: document nxp,gpio-pin-interrupt
...
Ian Kent [Tue, 15 Mar 2016 21:58:47 +0000 (14:58 -0700)]
autofs4: fix string.h include in auto_dev-ioctl.h
Since including linux/string.h will now do the right thing remove the
conditional check.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ian Kent [Tue, 15 Mar 2016 21:58:45 +0000 (14:58 -0700)]
autofs4: use pr_xxx() macros directly for logging
Use the standard pr_xxx() log macros directly for log prints instead of
the AUTOFS_XXX() macros.
Signed-off-by: Ian Kent <ikent@redhat.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ian Kent [Tue, 15 Mar 2016 21:58:42 +0000 (14:58 -0700)]
autofs4: change log print macros to not insert newline
Common kernel coding practice is to include the newline of log prints
within the log text rather than hidden away in a macro.
To avoid introducing inconsistencies as changes are made change the log
macros to not include the newline.
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ian Kent [Tue, 15 Mar 2016 21:58:39 +0000 (14:58 -0700)]
autofs4: make autofs log prints consistent
Use the pr_*() print in AUTOFS_*() macros instead of printks and include
the module name in log message macros. Also use the AUTOFS_*() macros
everywhere instead of raw printks.
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ian Kent [Tue, 15 Mar 2016 21:58:36 +0000 (14:58 -0700)]
autofs4: fix some white space errors
Fix some white space format errors.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ian Kent [Tue, 15 Mar 2016 21:58:33 +0000 (14:58 -0700)]
autofs4: fix invalid ioctl return in autofs4_root_ioctl_unlocked()
The return from an ioctl if an invalid ioctl is passed in should be
EINVAL not ENOSYS.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ian Kent [Tue, 15 Mar 2016 21:58:30 +0000 (14:58 -0700)]
autofs4: fix coding style line length in autofs4_wait()
The need for this is questionable but checkpatch.pl complains about the
line length and it's a straightfoward change.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ian Kent [Tue, 15 Mar 2016 21:58:28 +0000 (14:58 -0700)]
autofs4: fix coding style problem in autofs4_get_set_timeout()
Refactor autofs4_get_set_timeout() to eliminate coding style error.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ian Kent [Tue, 15 Mar 2016 21:58:25 +0000 (14:58 -0700)]
autofs4: coding style fixes
Try and make the coding style completely consistent throughtout the
autofs module and inline with kernel coding style recommendations.
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Stanislav Kinsburskiy [Tue, 15 Mar 2016 21:58:22 +0000 (14:58 -0700)]
autofs: show pipe inode in mount options
This is required for CRIU (Checkpoint Restart In Userspace) to migrate a
mount point when write end in user space is closed.
Below is a brief description of the problem.
To migrate a non-catatonic autofs mount point, one has to restore the
control pipe between kernel and autofs master process.
One of the autofs masters is systemd, which closes pipe write end after
passing it to the kernel with mount call.
To be able to restore the systemd control pipe one has to know which
read pipe end in systemd corresponds to the write pipe end in the
kernel. The pipe "fd" in mount options is not enough because it was
closed and probably replaced by some other descriptor.
Thus, some other attribute is required to be able to find the read pipe
end. The best attribute to use to find the correct pipe end is inode
number becuase it's unique for the whole system and can't be reused
while the autofs mount exists.
This attribute can also be used to recognize a situation where an autofs
mount has no master (no process with specified "pgrp" or no file
descriptor with "pipe_ino", specified in autofs mount options).
Signed-off-by: Stanislav Kinsburskiy <skinsbursky@virtuozzo.com>
Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ard Biesheuvel [Tue, 15 Mar 2016 21:58:19 +0000 (14:58 -0700)]
kallsyms: add support for relative offsets in kallsyms address table
Similar to how relative extables are implemented, it is possible to emit
the kallsyms table in such a way that it contains offsets relative to
some anchor point in the kernel image rather than absolute addresses.
On 64-bit architectures, it cuts the size of the kallsyms address table
in half, since offsets between kernel symbols can typically be expressed
in 32 bits. This saves several hundreds of kilobytes of permanent
.rodata on average. In addition, the kallsyms address table is no
longer subject to dynamic relocation when CONFIG_RELOCATABLE is in
effect, so the relocation work done after decompression now doesn't have
to do relocation updates for all these values. This saves up to 24
bytes (i.e., the size of a ELF64 RELA relocation table entry) per value,
which easily adds up to a couple of megabytes of uncompressed __init
data on ppc64 or arm64. Even if these relocation entries typically
compress well, the combined size reduction of 2.8 MB uncompressed for a
ppc64_defconfig build (of which 2.4 MB is __init data) results in a ~500
KB space saving in the compressed image.
Since it is useful for some architectures (like x86) to retain the
ability to emit absolute values as well, this patch also adds support
for capturing both absolute and relative values when
KALLSYMS_ABSOLUTE_PERCPU is in effect, by emitting absolute per-cpu
addresses as positive 32-bit values, and addresses relative to the
lowest encountered relative symbol as negative values, which are
subtracted from the runtime address of this base symbol to produce the
actual address.
Support for the above is enabled by default for all architectures except
IA-64 and Tile-GX, whose symbols are too far apart to capture in this
manner.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ard Biesheuvel [Tue, 15 Mar 2016 21:58:15 +0000 (14:58 -0700)]
kallsyms: don't overload absolute symbol type for percpu symbols
Commit
c6bda7c988a5 ("kallsyms: fix percpu vars on x86-64 with
relocation") overloaded the 'A' (absolute) symbol type to signify that a
symbol is not subject to dynamic relocation. However, the original A
type does not imply that at all, and depending on the version of the
toolchain, many A type symbols are emitted that are in fact relative to
the kernel text, i.e., if the kernel is relocated at runtime, these
symbols should be updated as well.
For instance, on sparc32, the following symbols are emitted as absolute
(kindly provided by Guenter Roeck):
f035a420 A _etext
f03d9000 A _sdata
f03de8c4 A jiffies
f03f8860 A _edata
f03fc000 A __init_begin
f041bdc8 A __init_text_end
f0423000 A __bss_start
f0423000 A __init_end
f044457d A __bss_stop
f044457d A _end
On x86_64, similar behavior can be observed:
ffffffff81a00000 A __end_rodata_hpage_align
ffffffff81b19000 A __vvar_page
ffffffff81d3d000 A _end
Even if only a couple of them pass the symbol range check that results
in them to be taken into account for the final kallsyms symbol table, it
is obvious that 'A' does not mean the symbol does not need to be updated
at relocation time, and overloading its meaning to signify that is
perhaps not a good idea.
So instead, add a new percpu_absolute member to struct sym_entry, and
when --absolute-percpu is in effect, use it to record symbols whose
addresses should be emitted as final values rather than values that
still require relocation at runtime. That way, we can drop the check
against the 'A' type.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Marek <mmarek@suse.cz>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ard Biesheuvel [Tue, 15 Mar 2016 21:58:12 +0000 (14:58 -0700)]
x86: kallsyms: disable absolute percpu symbols on !SMP
scripts/kallsyms.c has a special --absolute-percpu command line option
which deals with the zero based per cpu offsets that are used when
building for SMP on x86_64. This means that the option should only be
passed in that case, so add a Kconfig symbol with the correct predicate,
and use that instead.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Kees Cook <keescook@chromium.org>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Geyslan G. Bem [Tue, 15 Mar 2016 21:58:09 +0000 (14:58 -0700)]
checkpatch: fix another left brace warning
This patch escapes a regex that uses left brace.
Using checkpatch.pl with Perl 5.22.0 generates the warning: "Unescaped
left brace in regex is deprecated, passed through in regex;"
Comment from regcomp.c in Perl source: "Currently we don't warn when the
lbrace is at the start of a construct. This catches it in the middle of
a literal string, or when it's the first thing after something like
"\b"."
This works as a complement to
4e5d56bd ("checkpatch: fix left brace
warning").
Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Joe Perches <joe@perches.com>
Suggested-by: Peter Senna Tschudin <peter.senna@gmail.com>
Cc: Eddie Kovsky <ewk@edkovsky.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Tue, 15 Mar 2016 21:58:06 +0000 (14:58 -0700)]
checkpatch: improve UNSPECIFIED_INT test for bare signed/unsigned uses
Improve the test to allow casts to (unsigned) or (signed) to be found
and fixed if desired.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Tue, 15 Mar 2016 21:58:03 +0000 (14:58 -0700)]
checkpatch: warn on bare unsigned or signed declarations without int
Kernel style prefers "unsigned int <foo>" over "unsigned <foo>" and
"signed int <foo>" over "signed <foo>".
Emit a warning for these simple signed/unsigned <foo> declarations. Fix
it too if desired.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Tue, 15 Mar 2016 21:58:01 +0000 (14:58 -0700)]
checkpatch: exclude asm volatile from complex macro check
asm volatile and all its variants like __asm__ __volatile__ ("<foo>")
are reported as errors with "Macros with with complex values should be
enclosed in parentheses".
Make an exception for these asm volatile macro definitions by converting
the "asm volatile" to "asm_volatile" so it appears as a single function
call and the error isn't reported.
Signed-off-by: Joe Perches <joe@perches.com>
Reported-by: Jeff Merkey <linux.mdb@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 15 Mar 2016 21:57:58 +0000 (14:57 -0700)]
mm: memcontrol: drop unnecessary lru locking from mem_cgroup_migrate()
Migration accounting in the memory controller used to have to handle
both oldpage and newpage being on the LRU already; fuse's page cache
replacement used to pass a recycled newpage that had been uncharged but
not freed and removed from the LRU, and the memcg migration code used to
uncharge oldpage to "pass on" the existing charge to newpage.
Nowadays, pages are no longer uncharged when truncated from the page
cache, but rather only at free time, so if a LRU page is recycled in
page cache replacement it'll also still be charged. And we bail out of
the charge transfer altogether in that case. Tell commit_charge() that
we know newpage is not on the LRU, to avoid taking the zone->lru_lock
unnecessarily from the migration path.
But also, oldpage is no longer uncharged inside migration. We only use
oldpage for its page->mem_cgroup and page size, so we don't care about
its LRU state anymore either. Remove any mention from the kernel doc.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Hugh Dickins <hughd@google.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 15 Mar 2016 21:57:54 +0000 (14:57 -0700)]
mm: migrate: consolidate mem_cgroup_migrate() calls
Rather than scattering mem_cgroup_migrate() calls all over the place,
have a single call from a safe place where every migration operation
eventually ends up in - migrate_page_copy().
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Hugh Dickins <hughd@google.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mateusz Guzik <mguzik@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Tue, 15 Mar 2016 21:57:51 +0000 (14:57 -0700)]
mm/compaction: speed up pageblock_pfn_to_page() when zone is contiguous
There is a performance drop report due to hugepage allocation and in
there half of cpu time are spent on pageblock_pfn_to_page() in
compaction [1].
In that workload, compaction is triggered to make hugepage but most of
pageblocks are un-available for compaction due to pageblock type and
skip bit so compaction usually fails. Most costly operations in this
case is to find valid pageblock while scanning whole zone range. To
check if pageblock is valid to compact, valid pfn within pageblock is
required and we can obtain it by calling pageblock_pfn_to_page(). This
function checks whether pageblock is in a single zone and return valid
pfn if possible. Problem is that we need to check it every time before
scanning pageblock even if we re-visit it and this turns out to be very
expensive in this workload.
Although we have no way to skip this pageblock check in the system where
hole exists at arbitrary position, we can use cached value for zone
continuity and just do pfn_to_page() in the system where hole doesn't
exist. This optimization considerably speeds up in above workload.
Before vs After
Max: 1096 MB/s vs 1325 MB/s
Min: 635 MB/s 1015 MB/s
Avg: 899 MB/s 1194 MB/s
Avg is improved by roughly 30% [2].
[1]: http://www.spinics.net/lists/linux-mm/msg97378.html
[2]: https://lkml.org/lkml/2015/12/9/23
[akpm@linux-foundation.org: don't forget to restore zone->contiguous on error path, per Vlastimil]
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reported-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Tested-by: Aaron Lu <aaron.lu@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Tue, 15 Mar 2016 21:57:48 +0000 (14:57 -0700)]
mm/compaction: pass only pageblock aligned range to pageblock_pfn_to_page
pageblock_pfn_to_page() is used to check there is valid pfn and all
pages in the pageblock is in a single zone. If there is a hole in the
pageblock, passing arbitrary position to pageblock_pfn_to_page() could
cause to skip whole pageblock scanning, instead of just skipping the
hole page. For deterministic behaviour, it's better to always pass
pageblock aligned range to pageblock_pfn_to_page(). It will also help
further optimization on pageblock_pfn_to_page() in the following patch.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joonsoo Kim [Tue, 15 Mar 2016 21:57:45 +0000 (14:57 -0700)]
mm/compaction: fix invalid free_pfn and compact_cached_free_pfn
free_pfn and compact_cached_free_pfn are the pointer that remember
restart position of freepage scanner. When they are reset or invalid,
we set them to zone_end_pfn because freepage scanner works in reverse
direction. But, because zone range is defined as [zone_start_pfn,
zone_end_pfn), zone_end_pfn is invalid to access. Therefore, we should
not store it to free_pfn and compact_cached_free_pfn. Instead, we need
to store zone_end_pfn - 1 to them. There is one more thing we should
consider. Freepage scanner scan reversely by pageblock unit. If
free_pfn and compact_cached_free_pfn are set to middle of pageblock, it
regards that sitiation as that it already scans front part of pageblock
so we lose opportunity to scan there. To fix-up, this patch do
round_down() to guarantee that reset position will be pageblock aligned.
Note that thanks to the current pageblock_pfn_to_page() implementation,
actual access to zone_end_pfn doesn't happen until now. But, following
patch will change pageblock_pfn_to_page() so this patch is needed from
now on.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alexander Kuleshov [Tue, 15 Mar 2016 21:57:42 +0000 (14:57 -0700)]
mm/memblock.c: remove unnecessary memblock_type variable
We define struct memblock_type *type in the memblock_add_region() and
memblock_reserve_region() functions only for passing it to the
memlock_add_range() and memblock_reserve_range() functions. Let's
remove these variables and will pass a type directly.
Signed-off-by: Alexander Kuleshov <kuleshovmail@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christian Borntraeger [Tue, 15 Mar 2016 21:57:39 +0000 (14:57 -0700)]
x86: also use debug_pagealloc_enabled() for free_init_pages
we want to couple all debugging features with debug_pagealloc_enabled()
and not with the config option CONFIG_DEBUG_PAGEALLOC.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Suggested-by: David Rientjes <rientjes@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Laura Abbott <labbott@fedoraproject.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christian Borntraeger [Tue, 15 Mar 2016 21:57:36 +0000 (14:57 -0700)]
s390: query dynamic DEBUG_PAGEALLOC setting
We can use debug_pagealloc_enabled() to check if we can map the identity
mapping with 1MB/2GB pages as well as to print the current setting in
dump_stack.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Laura Abbott <labbott@fedoraproject.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Christian Borntraeger [Tue, 15 Mar 2016 21:57:33 +0000 (14:57 -0700)]
x86: query dynamic DEBUG_PAGEALLOC setting
We can use debug_pagealloc_enabled() to check if we can map the identity
mapping with 2MB pages. We can also add the state into the dump_stack
output.
The patch does not touch the code for the 1GB pages, which ignored
CONFIG_DEBUG_PAGEALLOC. Do we need to fence this as well?
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Laura Abbott <labbott@fedoraproject.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kirill A. Shutemov [Tue, 15 Mar 2016 21:57:30 +0000 (14:57 -0700)]
thp: cleanup split_huge_page()
After one of bugfixes to freeze_page(), we don't have freezed pages in
rmap, therefore mapcount of all subpages of freezed THP is zero. And we
have assert for that.
Let's drop code which deal with non-zero mapcount of subpages.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Matthew Wilcox [Tue, 15 Mar 2016 21:57:28 +0000 (14:57 -0700)]
mm: use linear_page_index() in do_fault()
do_fault() assumes that PAGE_SIZE is the same as PAGE_CACHE_SIZE. Use
linear_page_index() to calculate pgoff in the correct units.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 15 Mar 2016 21:57:25 +0000 (14:57 -0700)]
mm: remove unnecessary uses of lock_page_memcg()
There are several users that nest lock_page_memcg() inside lock_page()
to prevent page->mem_cgroup from changing. But the page lock prevents
pages from moving between cgroups, so that is unnecessary overhead.
Remove lock_page_memcg() in contexts with locked contexts and fix the
debug code in the page stat functions to be okay with the page lock.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 15 Mar 2016 21:57:22 +0000 (14:57 -0700)]
mm: simplify lock_page_memcg()
Now that migration doesn't clear page->mem_cgroup of live pages anymore,
it's safe to make lock_page_memcg() and the memcg stat functions take
pages, and spare the callers from memcg objects.
[akpm@linux-foundation.org: fix warnings]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 15 Mar 2016 21:57:19 +0000 (14:57 -0700)]
mm: migrate: do not touch page->mem_cgroup of live pages
Changing a page's memcg association complicates dealing with the page,
so we want to limit this as much as possible. Page migration e.g. does
not have to do that. Just like page cache replacement, it can forcibly
charge a replacement page, and then uncharge the old page when it gets
freed. Temporarily overcharging the cgroup by a single page is not an
issue in practice, and charging is so cheap nowadays that this is much
preferrable to the headache of messing with live pages.
The only place that still changes the page->mem_cgroup binding of live
pages is when pages move along with a task to another cgroup. But that
path isolates the page from the LRU, takes the page lock, and the move
lock (lock_page_memcg()). That means page->mem_cgroup is always stable
in callers that have the page isolated from the LRU or locked. Lighter
unlocked paths, like writeback accounting, can use lock_page_memcg().
[akpm@linux-foundation.org: fix build]
[vdavydov@virtuozzo.com: fix lockdep splat]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 15 Mar 2016 21:57:16 +0000 (14:57 -0700)]
mm: workingset: per-cgroup cache thrash detection
Cache thrash detection (see
a528910e12ec "mm: thrash detection-based
file cache sizing" for details) currently only works on the system
level, not inside cgroups. Worse, as the refaults are compared to the
global number of active cache, cgroups might wrongfully get all their
refaults activated when their pages are hotter than those of others.
Move the refault machinery from the zone to the lruvec, and then tag
eviction entries with the memcg ID. This makes the thrash detection
work correctly inside cgroups.
[sergey.senozhatsky@gmail.com: do not return from workingset_activation() with locked rcu and page]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 15 Mar 2016 21:57:13 +0000 (14:57 -0700)]
mm: workingset: eviction buckets for bigmem/lowbit machines
For per-cgroup thrash detection, we need to store the memcg ID inside
the radix tree cookie as well. However, on 32 bit that doesn't leave
enough bits for the eviction timestamp to cover the necessary range of
recently evicted pages. The radix tree entry would look like this:
[ RADIX_TREE_EXCEPTIONAL(2) | ZONEID(2) | MEMCGID(16) | EVICTION(12) ]
12 bits means 4096 pages, means 16M worth of recently evicted pages.
But refaults are actionable up to distances covering half of memory. To
not miss refaults, we have to stretch out the range at the cost of how
precisely we can tell when a page was evicted. This way we can shave
off lower bits from the eviction timestamp until the necessary range is
covered. E.g. grouping evictions into 1M buckets (256 pages) will
stretch the longest representable refault distance to 4G.
This patch implements eviction buckets that are automatically sized
according to the available bits and the necessary refault range, in
preparation for per-cgroup thrash detection.
The maximum actionable distance is currently half of memory, but to
support memory hotplug of up to 200% of boot-time memory, we size the
buckets to cover double the distance. Beyond that, thrashing won't be
detectable anymore.
During boot, the kernel will print out the exact parameters, like so:
[ 0.113929] workingset: timestamp_bits=12 max_order=18 bucket_order=6
In this example, there are 12 radix entry bits available for the
eviction timestamp, to cover a maximum distance of 2^18 pages (this is a
1G machine). Consequently, evictions must be grouped into buckets of
2^6 pages, or 256K.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Johannes Weiner [Tue, 15 Mar 2016 21:57:10 +0000 (14:57 -0700)]
mm: workingset: separate shadow unpacking and refault calculation
Per-cgroup thrash detection will need to derive a live memcg from the
eviction cookie, and doing that inside unpack_shadow() will get nasty
with the reference handling spread over two functions.
In preparation, make unpack_shadow() clearly about extracting static
data, and let workingset_refault() do all the higher-level handling.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / openwrt / staging / blogic.git / log