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383 Commits

Author SHA1 Message Date
Sultan Alsawaf
e471ef806d mm: Move slab shrinkers into a dedicated thread called kshrinkd
Slab shrinkers are unique in that they have no bearing on direct reclaim
throttling and reclaim statistics, meaning that they can be completely
decoupled from the kswapd and direct reclaim paths, making them faster.
Further justification for this is that shrinkers may be slow and aren't
guaranteed to free any memory, which means that they can waste kswapd
and direct reclaim time without producing results. Running the same
shrinker concurrently can also produce unwanted lock contention inside
the shrinker itself.

An empirical test of checking how long kswapd and kshrinkd ran on a
memory constrained system showed that kshrinkd ran for about 10% of the
duration that kswapd ran, which indicates significant savings.

Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
2022-11-28 11:08:54 +02:00
pwnrazr
a8ea33e97f Revert "Revert "[SQUASH] mm: revert recent changes to kswpad""
This reverts commit 4df043fc41bbb86de9a0d36c3f1989884ad49edb.
2022-10-07 12:15:36 +03:00
John Galt
ff0a272a32 kswapd: move to 8 threads 2022-07-18 06:35:09 +00:00
John Galt
d94b916d8a Revert "mm: Move slab shrinkers into a dedicated thread called kshrinkd"
This reverts commit 849afca4f00697606c4c16c788305a7591518282.
2022-07-18 06:34:56 +00:00
XeonDead
f128cc392c kswapd_threads: 4 and run on small cluster
Change-Id: Ied0019d908dfa04f794cb3ceeaa1f01193076456
2022-07-18 06:32:50 +00:00
Buddy Lumpkin
5950d42926 vmscan: Support multiple kswapd threads per node
Page replacement is handled in the Linux Kernel in one of two ways:

1) Asynchronously via kswapd
2) Synchronously, via direct reclaim

At page allocation time the allocating task is immediately given a page
from the zone free list allowing it to go right back to work doing
whatever it was doing; Probably directly or indirectly executing business
logic.

Just prior to satisfying the allocation, free pages is checked to see if
it has reached the zone low watermark and if so, kswapd is awakened.
Kswapd will start scanning pages looking for inactive pages to evict to
make room for new page allocations. The work of kswapd allows tasks to
continue allocating memory from their respective zone free list without
incurring any delay.

When the demand for free pages exceeds the rate that kswapd tasks can
supply them, page allocation works differently. Once the allocating task
finds that the number of free pages is at or below the zone min watermark,
the task will no longer pull pages from the free list. Instead, the task
will run the same CPU-bound routines as kswapd to satisfy its own
allocation by scanning and evicting pages. This is called a direct reclaim.

The time spent performing a direct reclaim can be substantial, often
taking tens to hundreds of milliseconds for small order0 allocations to
half a second or more for order9 huge-page allocations. In fact, kswapd is
not actually required on a linux system. It exists for the sole purpose of
optimizing performance by preventing direct reclaims.

When memory shortfall is sufficient to trigger direct reclaims, they can
occur in any task that is running on the system. A single aggressive
memory allocating task can set the stage for collateral damage to occur in
small tasks that rarely allocate additional memory. Consider the impact of
injecting an additional 100ms of latency when nscd allocates memory to
facilitate caching of a DNS query.

The presence of direct reclaims 10 years ago was a fairly reliable
indicator that too much was being asked of a Linux system. Kswapd was
likely wasting time scanning pages that were ineligible for eviction.
Adding RAM or reducing the working set size would usually make the problem
go away. Since then hardware has evolved to bring a new struggle for
kswapd. Storage speeds have increased by orders of magnitude while CPU
clock speeds stayed the same or even slowed down in exchange for more
cores per package. This presents a throughput problem for a single
threaded kswapd that will get worse with each generation of new hardware.

Test Details

NOTE: The tests below were run with shadow entries disabled. See the
associated patch and cover letter for details

The tests below were designed with the assumption that a kswapd bottleneck
is best demonstrated using filesystem reads. This way, the inactive list
will be full of clean pages, simplifying the analysis and allowing kswapd
to achieve the highest possible steal rate. Maximum steal rates for kswapd
are likely to be the same or lower for any other mix of page types on the
system.

Tests were run on a 2U Oracle X7-2L with 52 Intel Xeon Skylake 2GHz cores,
756GB of RAM and 8 x 3.6 TB NVMe Solid State Disk drives. Each drive has
an XFS file system mounted separately as /d0 through /d7. SSD drives
require multiple concurrent streams to show their potential, so I created
eleven 250GB zero-filled files on each drive so that I could test with
parallel reads.

The test script runs in multiple stages. At each stage, the number of dd
tasks run concurrently is increased by 2. I did not include all of the
test output for brevity.

During each stage dd tasks are launched to read from each drive in a round
robin fashion until the specified number of tasks for the stage has been
reached. Then iostat, vmstat and top are started in the background with 10
second intervals. After five minutes, all of the dd tasks are killed and
the iostat, vmstat and top output is parsed in order to report the
following:

CPU consumption
- sy - aggregate kernel mode CPU consumption from vmstat output. The value
       doesn't tend to fluctuate much so I just grab the highest value.
       Each sample is averaged over 10 seconds
- dd_cpu - for all of the dd tasks averaged across the top samples since
           there is a lot of variation.

Throughput
- in Kbytes
- Command is iostat -x -d 10 -g total

This first test performs reads using O_DIRECT in order to show the maximum
throughput that can be obtained using these drives. It also demonstrates
how rapidly throughput scales as the number of dd tasks are increased.

The dd command for this test looks like this:

Command Used: dd iflag=direct if=/d${i}/$n of=/dev/null bs=4M

Test #1: Direct IO
dd sy dd_cpu throughput
6  0  2.33   14726026.40
10 1  2.95   19954974.80
16 1  2.63   24419689.30
22 1  2.63   25430303.20
28 1  2.91   26026513.20
34 1  2.53   26178618.00
40 1  2.18   26239229.20
46 1  1.91   26250550.40
52 1  1.69   26251845.60
58 1  1.54   26253205.60
64 1  1.43   26253780.80
70 1  1.31   26254154.80
76 1  1.21   26253660.80
82 1  1.12   26254214.80
88 1  1.07   26253770.00
90 1  1.04   26252406.40

Throughput was close to peak with only 22 dd tasks. Very little system CPU
was consumed as expected as the drives DMA directly into the user address
space when using direct IO.

In this next test, the iflag=direct option is removed and we only run the
test until the pgscan_kswapd from /proc/vmstat starts to increment. At
that point metrics are parsed and reported and the pagecache contents are
dropped prior to the next test. Lather, rinse, repeat.

Test #2: standard file system IO, no page replacement
dd sy dd_cpu throughput
6  2  28.78  5134316.40
10 3  31.40  8051218.40
16 5  34.73  11438106.80
22 7  33.65  14140596.40
28 8  31.24  16393455.20
34 10 29.88  18219463.60
40 11 28.33  19644159.60
46 11 25.05  20802497.60
52 13 26.92  22092370.00
58 13 23.29  22884881.20
64 14 23.12  23452248.80
70 15 22.40  23916468.00
76 16 22.06  24328737.20
82 17 20.97  24718693.20
88 16 18.57  25149404.40
90 16 18.31  25245565.60

Each read has to pause after the buffer in kernel space is populated while
those pages are added to the pagecache and copied into the user address
space. For this reason, more parallel streams are required to achieve peak
throughput. The copy operation consumes substantially more CPU than direct
IO as expected.

The next test measures throughput after kswapd starts running. This is the
same test only we wait for kswapd to wake up before we start collecting
metrics. The script actually keeps track of a few things that were not
mentioned earlier. It tracks direct reclaims and page scans by watching
the metrics in /proc/vmstat. CPU consumption for kswapd is tracked the
same way it is tracked for dd.

Since the test is 100% reads, you can assume that the page steal rate for
kswapd and direct reclaims is almost identical to the scan rate.

Test #3: 1 kswapd thread per node
dd sy dd_cpu kswapd0 kswapd1 throughput  dr    pgscan_kswapd pgscan_direct
10 4  26.07  28.56   27.03   7355924.40  0     459316976     0
16 7  34.94  69.33   69.66   10867895.20 0     872661643     0
22 10 36.03  93.99   99.33   13130613.60 489   1037654473    11268334
28 10 30.34  95.90   98.60   14601509.60 671   1182591373    15429142
34 14 34.77  97.50   99.23   16468012.00 10850 1069005644    249839515
40 17 36.32  91.49   97.11   17335987.60 18903 975417728     434467710
46 19 38.40  90.54   91.61   17705394.40 25369 855737040     582427973
52 22 40.88  83.97   83.70   17607680.40 31250 709532935     724282458
58 25 40.89  82.19   80.14   17976905.60 35060 657796473     804117540
64 28 41.77  73.49   75.20   18001910.00 39073 561813658     895289337
70 33 45.51  63.78   64.39   17061897.20 44523 379465571     1020726436
76 36 46.95  57.96   60.32   16964459.60 47717 291299464     1093172384
82 39 47.16  55.43   56.16   16949956.00 49479 247071062     1134163008
88 42 47.41  53.75   47.62   16930911.20 51521 195449924     1180442208
90 43 47.18  51.40   50.59   16864428.00 51618 190758156     1183203901

In the previous test where kswapd was not involved, the system-wide kernel
mode CPU consumption with 90 dd tasks was 16%. In this test CPU consumption
with 90 tasks is at 43%. With 52 cores, and two kswapd tasks (one per NUMA
node), kswapd can only be responsible for a little over 4% of the increase.
The rest is likely caused by 51,618 direct reclaims that scanned 1.2
billion pages over the five minute time period of the test.

Same test, more kswapd tasks:

Test #4: 4 kswapd threads per node
dd sy dd_cpu kswapd0 kswapd1 throughput  dr    pgscan_kswapd pgscan_direct
10 5  27.09  16.65   14.17   7842605.60  0     459105291     0
16 10 37.12  26.02   24.85   11352920.40 15    920527796     358515
22 11 36.94  37.13   35.82   13771869.60 0     1132169011     0
28 13 35.23  48.43   46.86   16089746.00 0     1312902070     0
34 15 33.37  53.02   55.69   18314856.40 0     1476169080     0
40 19 35.90  69.60   64.41   19836126.80 0     1629999149     0
46 22 36.82  88.55   57.20   20740216.40 0     1708478106     0
52 24 34.38  93.76   68.34   21758352.00 0     1794055559     0
58 24 30.51  79.20   82.33   22735594.00 0     1872794397     0
64 26 30.21  97.12   76.73   23302203.60 176   1916593721     4206821
70 33 32.92  92.91   92.87   23776588.00 3575  1817685086     85574159
76 37 31.62  91.20   89.83   24308196.80 4752  1812262569     113981763
82 29 25.53  93.23   92.33   24802791.20 306   2032093122     7350704
88 43 37.12  76.18   77.01   25145694.40 20310 1253204719     487048202
90 42 38.56  73.90   74.57   22516787.60 22774 1193637495     545463615

By increasing the number of kswapd threads, throughput increased by ~50%
while kernel mode CPU utilization decreased or stayed the same, likely due
to a decrease in the number of parallel tasks at any given time doing page
replacement.

Change-Id: I966d4a9c33bad188b3409f7ceea1df205a63c3bd
Signed-off-by: Buddy Lumpkin <buddy.lumpkin@oracle.com>
Patch-mainline: linux-mm @ Mon,  2 Apr 2018 09:24:22
Link: https://lore.kernel.org/lkml/1522661062-39745-1-git-send-email-buddy.lumpkin@oracle.com
[charante@codeaurora.org]: Changes done to ensure QGKI compliance.
Signed-off-by: Charan Teja Kalla <charante@codeaurora.org>
2022-07-18 06:32:42 +00:00
Minchan Kim
add1061e0e FROMLIST: BACKPORT: mm: fix is_pinnable_page against on cma page
Pages on CMA area could have MIGRATE_ISOLATE as well as MIGRATE_CMA
so current is_pinnable_page could miss CMA pages which has MIGRATE_
ISOLATE. It ends up pinning CMA pages as longterm at pin_user_pages
APIs so CMA allocation keep failed until the pin is released.

     CPU 0                                   CPU 1 - Task B

cma_alloc
alloc_contig_range
                                        pin_user_pages_fast(FOLL_LONGTERM)
change pageblock as MIGRATE_ISOLATE
                                        internal_get_user_pages_fast
                                        lockless_pages_from_mm
                                        gup_pte_range
                                        try_grab_folio
                                        is_pinnable_page
                                          return true;
                                        So, pinned the page successfully.
page migration failure with pinned page
                                        ..
                                        .. After 30 sec
                                        unpin_user_page(page)

CMA allocation succeeded after 30 sec.

The CMA allocation path protects the migration type change race
using zone->lock but what GUP path need to know is just whether the
page is on CMA area or not rather than exact migration type.
Thus, we don't need zone->lock but just checks migration type in
either of (MIGRATE_ISOLATE and MIGRATE_CMA).

Adding the MIGRATE_ISOLATE check in is_pinnable_page could cause
rejecting of pinning pages on MIGRATE_ISOLATE pageblocks even
though it's neither CMA nor movable zone if the page is temporarily
unmovable. However, such a migration failure by unexpected temporal
refcount holding is general issue, not only come from MIGRATE_ISOLATE
and the MIGRATE_ISOLATE is also transient state like other temporal
elevated refcount problem.

Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>

Conflicts:
        include/linux/mm.h

1. There is no is_pinnable_page in 5.10

Link: https://lore.kernel.org/all/20220524171525.976723-1-minchan@kernel.org/
Bug: 231227007
Signed-off-by: Minchan Kim <minchan@google.com>
Change-Id: I5cdd2b8eefdd7e89658abd21c32aa84876ad7782
Signed-off-by: Juhyung Park <qkrwngud825@gmail.com>
2022-06-27 14:33:01 +00:00
Yu Zhao
6cad7185c8 FROMLIST: mm: multi-gen LRU: thrashing prevention
Add /sys/kernel/mm/lru_gen/min_ttl_ms for thrashing prevention, as
requested by many desktop users [1].

When set to value N, it prevents the working set of N milliseconds
from getting evicted. The OOM killer is triggered if this working set
cannot be kept in memory. Based on the average human detectable lag
(~100ms), N=1000 usually eliminates intolerable lags due to thrashing.
Larger values like N=3000 make lags less noticeable at the risk of
premature OOM kills.

Compared with the size-based approach, e.g., [2], this time-based
approach has the following advantages:
1. It is easier to configure because it is agnostic to applications
   and memory sizes.
2. It is more reliable because it is directly wired to the OOM killer.

[1] https://lore.kernel.org/lkml/Ydza%2FzXKY9ATRoh6@google.com/
[2] https://lore.kernel.org/lkml/20211130201652.2218636d@mail.inbox.lv/

Link: https://lore.kernel.org/r/20220309021230.721028-12-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I482d33f3beaf7723d2f3eeaaa5b4f12bcb9b48a1
2022-06-27 14:32:38 +00:00
Yu Zhao
54d9c5f519 FROMLIST: mm: multi-gen LRU: kill switch
Add /sys/kernel/mm/lru_gen/enabled as a kill switch. Components that
can be disabled include:
  0x0001: the multi-gen LRU core
  0x0002: walking page table, when arch_has_hw_pte_young() returns
          true
  0x0004: clearing the accessed bit in non-leaf PMD entries, when
          CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG=y
  [yYnN]: apply to all the components above
E.g.,
  echo y >/sys/kernel/mm/lru_gen/enabled
  cat /sys/kernel/mm/lru_gen/enabled
  0x0007
  echo 5 >/sys/kernel/mm/lru_gen/enabled
  cat /sys/kernel/mm/lru_gen/enabled
  0x0005

NB: the page table walks happen on the scale of seconds under heavy
memory pressure, in which case the mmap_lock contention is a lesser
concern, compared with the LRU lock contention and the I/O congestion.
So far the only well-known case of the mmap_lock contention happens on
Android, due to Scudo [1] which allocates several thousand VMAs for
merely a few hundred MBs. The SPF and the Maple Tree also have
provided their own assessments [2][3]. However, if walking page tables
does worsen the mmap_lock contention, the kill switch can be used to
disable it. In this case the multi-gen LRU will suffer a minor
performance degradation, as shown previously.

Clearing the accessed bit in non-leaf PMD entries can also be
disabled, since this behavior was not tested on x86 varieties other
than Intel and AMD.

[1] https://source.android.com/devices/tech/debug/scudo
[2] https://lore.kernel.org/lkml/20220128131006.67712-1-michel@lespinasse.org/
[3] https://lore.kernel.org/lkml/20220202024137.2516438-1-Liam.Howlett@oracle.com/

Link: https://lore.kernel.org/r/20220309021230.721028-11-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I71801d9470a2588cad8bfd14fbcfafc7b010aa03
2022-06-27 14:32:38 +00:00
Yu Zhao
c0367061af FROMLIST: mm: multi-gen LRU: support page table walks
To further exploit spatial locality, the aging prefers to walk page
tables to search for young PTEs and promote hot pages. A kill switch
will be added in the next patch to disable this behavior. When
disabled, the aging relies on the rmap only.

NB: this behavior has nothing similar with the page table scanning in
the 2.4 kernel [1], which searches page tables for old PTEs, adds cold
pages to swapcache and unmaps them.

To avoid confusion, the term "iteration" specifically means the
traversal of an entire mm_struct list; the term "walk" will be applied
to page tables and the rmap, as usual.

An mm_struct list is maintained for each memcg, and an mm_struct
follows its owner task to the new memcg when this task is migrated.
Given an lruvec, the aging iterates lruvec_memcg()->mm_list and calls
walk_page_range() with each mm_struct on this list to promote hot
pages before it increments max_seq.

When multiple page table walkers iterate the same list, each of them
gets a unique mm_struct; therefore they can run concurrently. Page
table walkers ignore any misplaced pages, e.g., if an mm_struct was
migrated, pages it left in the previous memcg will not be promoted
when its current memcg is under reclaim. Similarly, page table walkers
will not promote pages from nodes other than the one under reclaim.

This patch uses the following optimizations when walking page tables:
1. It tracks the usage of mm_struct's between context switches so that
   page table walkers can skip processes that have been sleeping since
   the last iteration.
2. It uses generational Bloom filters to record populated branches so
   that page table walkers can reduce their search space based on the
   query results, e.g., to skip page tables containing mostly holes or
   misplaced pages.
3. It takes advantage of the accessed bit in non-leaf PMD entries when
   CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG=y.
4. It does not zigzag between a PGD table and the same PMD table
   spanning multiple VMAs. IOW, it finishes all the VMAs within the
   range of the same PMD table before it returns to a PGD table. This
   improves the cache performance for workloads that have large
   numbers of tiny VMAs [2], especially when CONFIG_PGTABLE_LEVELS=5.

Server benchmark results:
  Single workload:
    fio (buffered I/O): no change

  Single workload:
    memcached (anon): +[5.5, 7.5]%
                         Ops/sec      KB/sec
      patch1-7:          1014393.57   39455.42
      patch1-8:          1078507.59   41949.15

  Configurations:
    no change

Client benchmark results:
  kswapd profiles:
    patch1-7
      45.54%  lzo1x_1_do_compress (real work)
       9.56%  page_vma_mapped_walk
       6.70%  _raw_spin_unlock_irq
       2.78%  ptep_clear_flush
       2.47%  do_raw_spin_lock
       2.22%  __zram_bvec_write
       1.87%  lru_gen_look_around
       1.78%  memmove
       1.77%  obj_malloc
       1.44%  free_unref_page_list

    patch1-8
      47.02%  lzo1x_1_do_compress (real work)
       6.73%  page_vma_mapped_walk
       6.14%  _raw_spin_unlock_irq
       3.39%  walk_pte_range
       2.63%  ptep_clear_flush
       2.29%  __zram_bvec_write
       2.10%  do_raw_spin_lock
       1.81%  memmove
       1.73%  obj_malloc
       1.53%  free_unref_page_list

  Configurations:
    no change

[1] https://lwn.net/Articles/23732/
[2] https://source.android.com/devices/tech/debug/scudo

Link: https://lore.kernel.org/r/20220309021230.721028-9-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I5a3c97cf8ebf8d65d5f9528cd979a637c190053e
2022-06-27 14:32:38 +00:00
Yu Zhao
09a2a70211 FROMLIST: mm: multi-gen LRU: exploit locality in rmap
Searching the rmap for PTEs mapping each page on an LRU list (to test
and clear the accessed bit) can be expensive because pages from
different VMAs (PA space) are not cache friendly to the rmap (VA
space). For workloads mostly using mapped pages, the rmap has a high
CPU cost in the reclaim path.

This patch exploits spatial locality to reduce the trips into the
rmap. When shrink_page_list() walks the rmap and finds a young PTE, a
new function lru_gen_look_around() scans at most BITS_PER_LONG-1
adjacent PTEs. On finding another young PTE, it clears the accessed
bit and updates the gen counter of the page mapped by this PTE to
(max_seq%MAX_NR_GENS)+1.

Server benchmark results:
  Single workload:
    fio (buffered I/O): no change

  Single workload:
    memcached (anon): +[4, 6]%
                         Ops/sec      KB/sec
      patch1-6:          964656.80    37520.88
      patch1-7:          1014393.57   39455.42

  Configurations:
    no change

Client benchmark results:
  kswapd profiles:
    patch1-6
      36.13%  lzo1x_1_do_compress (real work)
      19.16%  page_vma_mapped_walk
       6.55%  _raw_spin_unlock_irq
       4.02%  do_raw_spin_lock
       2.32%  anon_vma_interval_tree_iter_first
       2.11%  ptep_clear_flush
       1.76%  __zram_bvec_write
       1.64%  folio_referenced_one
       1.40%  memmove
       1.35%  obj_malloc

    patch1-7
      45.54%  lzo1x_1_do_compress (real work)
       9.56%  page_vma_mapped_walk
       6.70%  _raw_spin_unlock_irq
       2.78%  ptep_clear_flush
       2.47%  do_raw_spin_lock
       2.22%  __zram_bvec_write
       1.87%  lru_gen_look_around
       1.78%  memmove
       1.77%  obj_malloc
       1.44%  free_unref_page_list

  Configurations:
    no change

Link: https://lore.kernel.org/r/20220309021230.721028-8-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I9a290343840f3cf925c891c8e360c7cdc24ffb9c
2022-06-27 14:32:38 +00:00
Yu Zhao
42440bf2f0 FROMLIST: mm: multi-gen LRU: minimal implementation
To avoid confusion, the terms "promotion" and "demotion" will be
applied to the multi-gen LRU, as a new convention; the terms
"activation" and "deactivation" will be applied to the active/inactive
LRU, as usual.

The aging produces young generations. Given an lruvec, it increments
max_seq when max_seq-min_seq+1 approaches MIN_NR_GENS. The aging
promotes hot pages to the youngest generation when it finds them
accessed through page tables; the demotion of cold pages happens
consequently when it increments max_seq. The aging has the complexity
O(nr_hot_pages), since it is only interested in hot pages. Promotion
in the aging path does not require any LRU list operations, only the
updates of the gen counter and lrugen->nr_pages[]; demotion, unless as
the result of the increment of max_seq, requires LRU list operations,
e.g., lru_deactivate_fn().

The eviction consumes old generations. Given an lruvec, it increments
min_seq when the lists indexed by min_seq%MAX_NR_GENS become empty. A
feedback loop modeled after the PID controller monitors refaults over
anon and file types and decides which type to evict when both types
are available from the same generation.

Each generation is divided into multiple tiers. Tiers represent
different ranges of numbers of accesses through file descriptors. A
page accessed N times through file descriptors is in tier
order_base_2(N). Tiers do not have dedicated lrugen->lists[], only
bits in page->flags. In contrast to moving across generations, which
requires the LRU lock, moving across tiers only involves operations on
page->flags. The feedback loop also monitors refaults over all tiers
and decides when to protect pages in which tiers (N>1), using the
first tier (N=0,1) as a baseline. The first tier contains single-use
unmapped clean pages, which are most likely the best choices. The
eviction moves a page to the next generation, i.e., min_seq+1, if the
feedback loop decides so. This approach has the following advantages:
1. It removes the cost of activation in the buffered access path by
   inferring whether pages accessed multiple times through file
   descriptors are statistically hot and thus worth protecting in the
   eviction path.
2. It takes pages accessed through page tables into account and avoids
   overprotecting pages accessed multiple times through file
   descriptors. (Pages accessed through page tables are in the first
   tier, since N=0.)
3. More tiers provide better protection for pages accessed more than
   twice through file descriptors, when under heavy buffered I/O
   workloads.

Server benchmark results:
  Single workload:
    fio (buffered I/O): +[38, 40]%
                         IOPS         BW
      5.18-ed4643521e6a: 2547k        9989MiB/s
      patch1-6:          3540k        13.5GiB/s

  Single workload:
    memcached (anon): +[103, 107]%
                         Ops/sec      KB/sec
      5.18-ed4643521e6a: 469048.66    18243.91
      patch1-6:          964656.80    37520.88

  Configurations:
    CPU: two Xeon 6154
    Mem: total 256G

    Node 1 was only used as a ram disk to reduce the variance in the
    results.

    patch drivers/block/brd.c <<EOF
    99,100c99,100
    < 	gfp_flags = GFP_NOIO | __GFP_ZERO | __GFP_HIGHMEM;
    < 	page = alloc_page(gfp_flags);
    ---
    > 	gfp_flags = GFP_NOIO | __GFP_ZERO | __GFP_HIGHMEM | __GFP_THISNODE;
    > 	page = alloc_pages_node(1, gfp_flags, 0);
    EOF

    cat >>/etc/systemd/system.conf <<EOF
    CPUAffinity=numa
    NUMAPolicy=bind
    NUMAMask=0
    EOF

    cat >>/etc/memcached.conf <<EOF
    -m 184320
    -s /var/run/memcached/memcached.sock
    -a 0766
    -t 36
    -B binary
    EOF

    cat fio.sh
    modprobe brd rd_nr=1 rd_size=113246208
    swapoff -a
    mkfs.ext4 /dev/ram0
    mount -t ext4 /dev/ram0 /mnt

    mkdir /sys/fs/cgroup/user.slice/test
    echo 38654705664 >/sys/fs/cgroup/user.slice/test/memory.max
    echo $$ >/sys/fs/cgroup/user.slice/test/cgroup.procs
    fio -name=mglru --numjobs=72 --directory=/mnt --size=1408m \
      --buffered=1 --ioengine=io_uring --iodepth=128 \
      --iodepth_batch_submit=32 --iodepth_batch_complete=32 \
      --rw=randread --random_distribution=random --norandommap \
      --time_based --ramp_time=10m --runtime=5m --group_reporting

    cat memcached.sh
    modprobe brd rd_nr=1 rd_size=113246208
    swapoff -a
    mkswap /dev/ram0
    swapon /dev/ram0

    memtier_benchmark -S /var/run/memcached/memcached.sock \
      -P memcache_binary -n allkeys --key-minimum=1 \
      --key-maximum=65000000 --key-pattern=P:P -c 1 -t 36 \
      --ratio 1:0 --pipeline 8 -d 2000

    memtier_benchmark -S /var/run/memcached/memcached.sock \
      -P memcache_binary -n allkeys --key-minimum=1 \
      --key-maximum=65000000 --key-pattern=R:R -c 1 -t 36 \
      --ratio 0:1 --pipeline 8 --randomize --distinct-client-seed

Client benchmark results:
  kswapd profiles:
    5.18-ed4643521e6a
      39.56%  page_vma_mapped_walk
      19.32%  lzo1x_1_do_compress (real work)
       7.18%  do_raw_spin_lock
       4.23%  _raw_spin_unlock_irq
       2.26%  vma_interval_tree_subtree_search
       2.12%  vma_interval_tree_iter_next
       2.11%  folio_referenced_one
       1.90%  anon_vma_interval_tree_iter_first
       1.47%  ptep_clear_flush
       0.97%  __anon_vma_interval_tree_subtree_search

    patch1-6
      36.13%  lzo1x_1_do_compress (real work)
      19.16%  page_vma_mapped_walk
       6.55%  _raw_spin_unlock_irq
       4.02%  do_raw_spin_lock
       2.32%  anon_vma_interval_tree_iter_first
       2.11%  ptep_clear_flush
       1.76%  __zram_bvec_write
       1.64%  folio_referenced_one
       1.40%  memmove
       1.35%  obj_malloc

  Configurations:
    CPU: single Snapdragon 7c
    Mem: total 4G

    Chrome OS MemoryPressure [1]

[1] https://chromium.googlesource.com/chromiumos/platform/tast-tests/

Link: https://lore.kernel.org/r/20220309021230.721028-7-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I3fe4850006d7984cd9f4fd46134b826609dc2f86
2022-06-27 14:32:38 +00:00
Yu Zhao
25b12afce0 FROMLIST: mm: multi-gen LRU: groundwork
Evictable pages are divided into multiple generations for each lruvec.
The youngest generation number is stored in lrugen->max_seq for both
anon and file types as they are aged on an equal footing. The oldest
generation numbers are stored in lrugen->min_seq[] separately for anon
and file types as clean file pages can be evicted regardless of swap
constraints. These three variables are monotonically increasing.

Generation numbers are truncated into order_base_2(MAX_NR_GENS+1) bits
in order to fit into the gen counter in page->flags. Each truncated
generation number is an index to lrugen->lists[]. The sliding window
technique is used to track at least MIN_NR_GENS and at most
MAX_NR_GENS generations. The gen counter stores a value within [1,
MAX_NR_GENS] while a page is on one of lrugen->lists[]. Otherwise it
stores 0.

There are two conceptually independent procedures: "the aging", which
produces young generations, and "the eviction", which consumes old
generations. They form a closed-loop system, i.e., "the page reclaim".
Both procedures can be invoked from userspace for the purposes of
working set estimation and proactive reclaim. These features are
required to optimize job scheduling (bin packing) in data centers. The
variable size of the sliding window is designed for such use cases
[1][2].

To avoid confusion, the terms "hot" and "cold" will be applied to the
multi-gen LRU, as a new convention; the terms "active" and "inactive"
will be applied to the active/inactive LRU, as usual.

The protection of hot pages and the selection of cold pages are based
on page access channels and patterns. There are two access channels:
one through page tables and the other through file descriptors. The
protection of the former channel is by design stronger because:
1. The uncertainty in determining the access patterns of the former
   channel is higher due to the approximation of the accessed bit.
2. The cost of evicting the former channel is higher due to the TLB
   flushes required and the likelihood of encountering the dirty bit.
3. The penalty of underprotecting the former channel is higher because
   applications usually do not prepare themselves for major page
   faults like they do for blocked I/O. E.g., GUI applications
   commonly use dedicated I/O threads to avoid blocking the rendering
   threads.
There are also two access patterns: one with temporal locality and the
other without. For the reasons listed above, the former channel is
assumed to follow the former pattern unless VM_SEQ_READ or
VM_RAND_READ is present; the latter channel is assumed to follow the
latter pattern unless outlying refaults have been observed [3][4].

The next patch will address the "outlying refaults". Three macros,
i.e., LRU_REFS_WIDTH, LRU_REFS_PGOFF and LRU_REFS_MASK, used later are
added in this patch to make the entire patchset less diffy.

A page is added to the youngest generation on faulting. The aging
needs to check the accessed bit at least twice before handing this
page over to the eviction. The first check takes care of the accessed
bit set on the initial fault; the second check makes sure this page
has not been used since then. This protocol, AKA second chance,
requires a minimum of two generations, hence MIN_NR_GENS.

[1] https://dl.acm.org/doi/10.1145/3297858.3304053
[2] https://dl.acm.org/doi/10.1145/3503222.3507731
[3] https://lwn.net/Articles/495543/
[4] https://lwn.net/Articles/815342/

Link: https://lore.kernel.org/r/20220309021230.721028-6-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I333ec6a1d2abfa60d93d6adc190ed3eefe441512
2022-06-27 14:32:38 +00:00
Yu Zhao
f5ff961bff BACKPORT: mm: use self-explanatory macros rather than "2"
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Link: http://lkml.kernel.org/r/20200831175042.3527153-2-yuzhao@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit ed0173733dd468883198c3136284394320b8fad6)
Bug: 228114874
Change-Id: Ifbc0e8976a29d914ade5a84a8a1fff069cb2d3bb
2022-06-27 14:32:37 +00:00
kondors1995
0cca5fb93e Revert "Merge branch 'dev/mglru' into dev/12-2"
This reverts commit e3d1ce4d09, reversing
changes made to d3cf1f4d72.
2022-05-17 08:16:01 +00:00
Yu Zhao
75a895db11 FROMLIST: mm: multi-gen LRU: thrashing prevention
Add /sys/kernel/mm/lru_gen/min_ttl_ms for thrashing prevention, as
requested by many desktop users [1].

When set to value N, it prevents the working set of N milliseconds
from getting evicted. The OOM killer is triggered if this working set
cannot be kept in memory. Based on the average human detectable lag
(~100ms), N=1000 usually eliminates intolerable lags due to thrashing.
Larger values like N=3000 make lags less noticeable at the risk of
premature OOM kills.

Compared with the size-based approach, e.g., [2], this time-based
approach has the following advantages:
1. It is easier to configure because it is agnostic to applications
   and memory sizes.
2. It is more reliable because it is directly wired to the OOM killer.

[1] https://lore.kernel.org/lkml/Ydza%2FzXKY9ATRoh6@google.com/
[2] https://lore.kernel.org/lkml/20211130201652.2218636d@mail.inbox.lv/

Link: https://lore.kernel.org/r/20220309021230.721028-12-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I482d33f3beaf7723d2f3eeaaa5b4f12bcb9b48a1
2022-05-03 11:10:22 +00:00
Yu Zhao
db2f982ebb FROMLIST: mm: multi-gen LRU: kill switch
Add /sys/kernel/mm/lru_gen/enabled as a kill switch. Components that
can be disabled include:
  0x0001: the multi-gen LRU core
  0x0002: walking page table, when arch_has_hw_pte_young() returns
          true
  0x0004: clearing the accessed bit in non-leaf PMD entries, when
          CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG=y
  [yYnN]: apply to all the components above
E.g.,
  echo y >/sys/kernel/mm/lru_gen/enabled
  cat /sys/kernel/mm/lru_gen/enabled
  0x0007
  echo 5 >/sys/kernel/mm/lru_gen/enabled
  cat /sys/kernel/mm/lru_gen/enabled
  0x0005

NB: the page table walks happen on the scale of seconds under heavy
memory pressure, in which case the mmap_lock contention is a lesser
concern, compared with the LRU lock contention and the I/O congestion.
So far the only well-known case of the mmap_lock contention happens on
Android, due to Scudo [1] which allocates several thousand VMAs for
merely a few hundred MBs. The SPF and the Maple Tree also have
provided their own assessments [2][3]. However, if walking page tables
does worsen the mmap_lock contention, the kill switch can be used to
disable it. In this case the multi-gen LRU will suffer a minor
performance degradation, as shown previously.

Clearing the accessed bit in non-leaf PMD entries can also be
disabled, since this behavior was not tested on x86 varieties other
than Intel and AMD.

[1] https://source.android.com/devices/tech/debug/scudo
[2] https://lore.kernel.org/lkml/20220128131006.67712-1-michel@lespinasse.org/
[3] https://lore.kernel.org/lkml/20220202024137.2516438-1-Liam.Howlett@oracle.com/

Link: https://lore.kernel.org/r/20220309021230.721028-11-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I71801d9470a2588cad8bfd14fbcfafc7b010aa03
2022-05-03 11:10:21 +00:00
Yu Zhao
1e84d38423 FROMLIST: mm: multi-gen LRU: support page table walks
To further exploit spatial locality, the aging prefers to walk page
tables to search for young PTEs and promote hot pages. A kill switch
will be added in the next patch to disable this behavior. When
disabled, the aging relies on the rmap only.

NB: this behavior has nothing similar with the page table scanning in
the 2.4 kernel [1], which searches page tables for old PTEs, adds cold
pages to swapcache and unmaps them.

To avoid confusion, the term "iteration" specifically means the
traversal of an entire mm_struct list; the term "walk" will be applied
to page tables and the rmap, as usual.

An mm_struct list is maintained for each memcg, and an mm_struct
follows its owner task to the new memcg when this task is migrated.
Given an lruvec, the aging iterates lruvec_memcg()->mm_list and calls
walk_page_range() with each mm_struct on this list to promote hot
pages before it increments max_seq.

When multiple page table walkers iterate the same list, each of them
gets a unique mm_struct; therefore they can run concurrently. Page
table walkers ignore any misplaced pages, e.g., if an mm_struct was
migrated, pages it left in the previous memcg will not be promoted
when its current memcg is under reclaim. Similarly, page table walkers
will not promote pages from nodes other than the one under reclaim.

This patch uses the following optimizations when walking page tables:
1. It tracks the usage of mm_struct's between context switches so that
   page table walkers can skip processes that have been sleeping since
   the last iteration.
2. It uses generational Bloom filters to record populated branches so
   that page table walkers can reduce their search space based on the
   query results, e.g., to skip page tables containing mostly holes or
   misplaced pages.
3. It takes advantage of the accessed bit in non-leaf PMD entries when
   CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG=y.
4. It does not zigzag between a PGD table and the same PMD table
   spanning multiple VMAs. IOW, it finishes all the VMAs within the
   range of the same PMD table before it returns to a PGD table. This
   improves the cache performance for workloads that have large
   numbers of tiny VMAs [2], especially when CONFIG_PGTABLE_LEVELS=5.

Server benchmark results:
  Single workload:
    fio (buffered I/O): no change

  Single workload:
    memcached (anon): +[5.5, 7.5]%
                         Ops/sec      KB/sec
      patch1-7:          1014393.57   39455.42
      patch1-8:          1078507.59   41949.15

  Configurations:
    no change

Client benchmark results:
  kswapd profiles:
    patch1-7
      45.54%  lzo1x_1_do_compress (real work)
       9.56%  page_vma_mapped_walk
       6.70%  _raw_spin_unlock_irq
       2.78%  ptep_clear_flush
       2.47%  do_raw_spin_lock
       2.22%  __zram_bvec_write
       1.87%  lru_gen_look_around
       1.78%  memmove
       1.77%  obj_malloc
       1.44%  free_unref_page_list

    patch1-8
      47.02%  lzo1x_1_do_compress (real work)
       6.73%  page_vma_mapped_walk
       6.14%  _raw_spin_unlock_irq
       3.39%  walk_pte_range
       2.63%  ptep_clear_flush
       2.29%  __zram_bvec_write
       2.10%  do_raw_spin_lock
       1.81%  memmove
       1.73%  obj_malloc
       1.53%  free_unref_page_list

  Configurations:
    no change

[1] https://lwn.net/Articles/23732/
[2] https://source.android.com/devices/tech/debug/scudo

Link: https://lore.kernel.org/r/20220309021230.721028-9-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I5a3c97cf8ebf8d65d5f9528cd979a637c190053e
2022-05-03 11:10:21 +00:00
Yu Zhao
1bb75d617f FROMLIST: mm: multi-gen LRU: exploit locality in rmap
Searching the rmap for PTEs mapping each page on an LRU list (to test
and clear the accessed bit) can be expensive because pages from
different VMAs (PA space) are not cache friendly to the rmap (VA
space). For workloads mostly using mapped pages, the rmap has a high
CPU cost in the reclaim path.

This patch exploits spatial locality to reduce the trips into the
rmap. When shrink_page_list() walks the rmap and finds a young PTE, a
new function lru_gen_look_around() scans at most BITS_PER_LONG-1
adjacent PTEs. On finding another young PTE, it clears the accessed
bit and updates the gen counter of the page mapped by this PTE to
(max_seq%MAX_NR_GENS)+1.

Server benchmark results:
  Single workload:
    fio (buffered I/O): no change

  Single workload:
    memcached (anon): +[4, 6]%
                         Ops/sec      KB/sec
      patch1-6:          964656.80    37520.88
      patch1-7:          1014393.57   39455.42

  Configurations:
    no change

Client benchmark results:
  kswapd profiles:
    patch1-6
      36.13%  lzo1x_1_do_compress (real work)
      19.16%  page_vma_mapped_walk
       6.55%  _raw_spin_unlock_irq
       4.02%  do_raw_spin_lock
       2.32%  anon_vma_interval_tree_iter_first
       2.11%  ptep_clear_flush
       1.76%  __zram_bvec_write
       1.64%  folio_referenced_one
       1.40%  memmove
       1.35%  obj_malloc

    patch1-7
      45.54%  lzo1x_1_do_compress (real work)
       9.56%  page_vma_mapped_walk
       6.70%  _raw_spin_unlock_irq
       2.78%  ptep_clear_flush
       2.47%  do_raw_spin_lock
       2.22%  __zram_bvec_write
       1.87%  lru_gen_look_around
       1.78%  memmove
       1.77%  obj_malloc
       1.44%  free_unref_page_list

  Configurations:
    no change

Link: https://lore.kernel.org/r/20220309021230.721028-8-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I9a290343840f3cf925c891c8e360c7cdc24ffb9c
2022-05-03 11:10:21 +00:00
Yu Zhao
ed95143ac2 FROMLIST: mm: multi-gen LRU: minimal implementation
To avoid confusion, the terms "promotion" and "demotion" will be
applied to the multi-gen LRU, as a new convention; the terms
"activation" and "deactivation" will be applied to the active/inactive
LRU, as usual.

The aging produces young generations. Given an lruvec, it increments
max_seq when max_seq-min_seq+1 approaches MIN_NR_GENS. The aging
promotes hot pages to the youngest generation when it finds them
accessed through page tables; the demotion of cold pages happens
consequently when it increments max_seq. The aging has the complexity
O(nr_hot_pages), since it is only interested in hot pages. Promotion
in the aging path does not require any LRU list operations, only the
updates of the gen counter and lrugen->nr_pages[]; demotion, unless as
the result of the increment of max_seq, requires LRU list operations,
e.g., lru_deactivate_fn().

The eviction consumes old generations. Given an lruvec, it increments
min_seq when the lists indexed by min_seq%MAX_NR_GENS become empty. A
feedback loop modeled after the PID controller monitors refaults over
anon and file types and decides which type to evict when both types
are available from the same generation.

Each generation is divided into multiple tiers. Tiers represent
different ranges of numbers of accesses through file descriptors. A
page accessed N times through file descriptors is in tier
order_base_2(N). Tiers do not have dedicated lrugen->lists[], only
bits in page->flags. In contrast to moving across generations, which
requires the LRU lock, moving across tiers only involves operations on
page->flags. The feedback loop also monitors refaults over all tiers
and decides when to protect pages in which tiers (N>1), using the
first tier (N=0,1) as a baseline. The first tier contains single-use
unmapped clean pages, which are most likely the best choices. The
eviction moves a page to the next generation, i.e., min_seq+1, if the
feedback loop decides so. This approach has the following advantages:
1. It removes the cost of activation in the buffered access path by
   inferring whether pages accessed multiple times through file
   descriptors are statistically hot and thus worth protecting in the
   eviction path.
2. It takes pages accessed through page tables into account and avoids
   overprotecting pages accessed multiple times through file
   descriptors. (Pages accessed through page tables are in the first
   tier, since N=0.)
3. More tiers provide better protection for pages accessed more than
   twice through file descriptors, when under heavy buffered I/O
   workloads.

Server benchmark results:
  Single workload:
    fio (buffered I/O): +[38, 40]%
                         IOPS         BW
      5.18-ed4643521e6a: 2547k        9989MiB/s
      patch1-6:          3540k        13.5GiB/s

  Single workload:
    memcached (anon): +[103, 107]%
                         Ops/sec      KB/sec
      5.18-ed4643521e6a: 469048.66    18243.91
      patch1-6:          964656.80    37520.88

  Configurations:
    CPU: two Xeon 6154
    Mem: total 256G

    Node 1 was only used as a ram disk to reduce the variance in the
    results.

    patch drivers/block/brd.c <<EOF
    99,100c99,100
    < 	gfp_flags = GFP_NOIO | __GFP_ZERO | __GFP_HIGHMEM;
    < 	page = alloc_page(gfp_flags);
    ---
    > 	gfp_flags = GFP_NOIO | __GFP_ZERO | __GFP_HIGHMEM | __GFP_THISNODE;
    > 	page = alloc_pages_node(1, gfp_flags, 0);
    EOF

    cat >>/etc/systemd/system.conf <<EOF
    CPUAffinity=numa
    NUMAPolicy=bind
    NUMAMask=0
    EOF

    cat >>/etc/memcached.conf <<EOF
    -m 184320
    -s /var/run/memcached/memcached.sock
    -a 0766
    -t 36
    -B binary
    EOF

    cat fio.sh
    modprobe brd rd_nr=1 rd_size=113246208
    swapoff -a
    mkfs.ext4 /dev/ram0
    mount -t ext4 /dev/ram0 /mnt

    mkdir /sys/fs/cgroup/user.slice/test
    echo 38654705664 >/sys/fs/cgroup/user.slice/test/memory.max
    echo $$ >/sys/fs/cgroup/user.slice/test/cgroup.procs
    fio -name=mglru --numjobs=72 --directory=/mnt --size=1408m \
      --buffered=1 --ioengine=io_uring --iodepth=128 \
      --iodepth_batch_submit=32 --iodepth_batch_complete=32 \
      --rw=randread --random_distribution=random --norandommap \
      --time_based --ramp_time=10m --runtime=5m --group_reporting

    cat memcached.sh
    modprobe brd rd_nr=1 rd_size=113246208
    swapoff -a
    mkswap /dev/ram0
    swapon /dev/ram0

    memtier_benchmark -S /var/run/memcached/memcached.sock \
      -P memcache_binary -n allkeys --key-minimum=1 \
      --key-maximum=65000000 --key-pattern=P:P -c 1 -t 36 \
      --ratio 1:0 --pipeline 8 -d 2000

    memtier_benchmark -S /var/run/memcached/memcached.sock \
      -P memcache_binary -n allkeys --key-minimum=1 \
      --key-maximum=65000000 --key-pattern=R:R -c 1 -t 36 \
      --ratio 0:1 --pipeline 8 --randomize --distinct-client-seed

Client benchmark results:
  kswapd profiles:
    5.18-ed4643521e6a
      39.56%  page_vma_mapped_walk
      19.32%  lzo1x_1_do_compress (real work)
       7.18%  do_raw_spin_lock
       4.23%  _raw_spin_unlock_irq
       2.26%  vma_interval_tree_subtree_search
       2.12%  vma_interval_tree_iter_next
       2.11%  folio_referenced_one
       1.90%  anon_vma_interval_tree_iter_first
       1.47%  ptep_clear_flush
       0.97%  __anon_vma_interval_tree_subtree_search

    patch1-6
      36.13%  lzo1x_1_do_compress (real work)
      19.16%  page_vma_mapped_walk
       6.55%  _raw_spin_unlock_irq
       4.02%  do_raw_spin_lock
       2.32%  anon_vma_interval_tree_iter_first
       2.11%  ptep_clear_flush
       1.76%  __zram_bvec_write
       1.64%  folio_referenced_one
       1.40%  memmove
       1.35%  obj_malloc

  Configurations:
    CPU: single Snapdragon 7c
    Mem: total 4G

    Chrome OS MemoryPressure [1]

[1] https://chromium.googlesource.com/chromiumos/platform/tast-tests/

Link: https://lore.kernel.org/r/20220309021230.721028-7-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I3fe4850006d7984cd9f4fd46134b826609dc2f86
2022-05-03 11:10:21 +00:00
Yu Zhao
8d5d59536c FROMLIST: mm: multi-gen LRU: groundwork
Evictable pages are divided into multiple generations for each lruvec.
The youngest generation number is stored in lrugen->max_seq for both
anon and file types as they are aged on an equal footing. The oldest
generation numbers are stored in lrugen->min_seq[] separately for anon
and file types as clean file pages can be evicted regardless of swap
constraints. These three variables are monotonically increasing.

Generation numbers are truncated into order_base_2(MAX_NR_GENS+1) bits
in order to fit into the gen counter in page->flags. Each truncated
generation number is an index to lrugen->lists[]. The sliding window
technique is used to track at least MIN_NR_GENS and at most
MAX_NR_GENS generations. The gen counter stores a value within [1,
MAX_NR_GENS] while a page is on one of lrugen->lists[]. Otherwise it
stores 0.

There are two conceptually independent procedures: "the aging", which
produces young generations, and "the eviction", which consumes old
generations. They form a closed-loop system, i.e., "the page reclaim".
Both procedures can be invoked from userspace for the purposes of
working set estimation and proactive reclaim. These features are
required to optimize job scheduling (bin packing) in data centers. The
variable size of the sliding window is designed for such use cases
[1][2].

To avoid confusion, the terms "hot" and "cold" will be applied to the
multi-gen LRU, as a new convention; the terms "active" and "inactive"
will be applied to the active/inactive LRU, as usual.

The protection of hot pages and the selection of cold pages are based
on page access channels and patterns. There are two access channels:
one through page tables and the other through file descriptors. The
protection of the former channel is by design stronger because:
1. The uncertainty in determining the access patterns of the former
   channel is higher due to the approximation of the accessed bit.
2. The cost of evicting the former channel is higher due to the TLB
   flushes required and the likelihood of encountering the dirty bit.
3. The penalty of underprotecting the former channel is higher because
   applications usually do not prepare themselves for major page
   faults like they do for blocked I/O. E.g., GUI applications
   commonly use dedicated I/O threads to avoid blocking the rendering
   threads.
There are also two access patterns: one with temporal locality and the
other without. For the reasons listed above, the former channel is
assumed to follow the former pattern unless VM_SEQ_READ or
VM_RAND_READ is present; the latter channel is assumed to follow the
latter pattern unless outlying refaults have been observed [3][4].

The next patch will address the "outlying refaults". Three macros,
i.e., LRU_REFS_WIDTH, LRU_REFS_PGOFF and LRU_REFS_MASK, used later are
added in this patch to make the entire patchset less diffy.

A page is added to the youngest generation on faulting. The aging
needs to check the accessed bit at least twice before handing this
page over to the eviction. The first check takes care of the accessed
bit set on the initial fault; the second check makes sure this page
has not been used since then. This protocol, AKA second chance,
requires a minimum of two generations, hence MIN_NR_GENS.

[1] https://dl.acm.org/doi/10.1145/3297858.3304053
[2] https://dl.acm.org/doi/10.1145/3503222.3507731
[3] https://lwn.net/Articles/495543/
[4] https://lwn.net/Articles/815342/

Link: https://lore.kernel.org/r/20220309021230.721028-6-yuzhao@google.com/
Signed-off-by: Yu Zhao <yuzhao@google.com>
Acked-by: Brian Geffon <bgeffon@google.com>
Acked-by: Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Acked-by: Oleksandr Natalenko <oleksandr@natalenko.name>
Acked-by: Steven Barrett <steven@liquorix.net>
Acked-by: Suleiman Souhlal <suleiman@google.com>
Tested-by: Daniel Byrne <djbyrne@mtu.edu>
Tested-by: Donald Carr <d@chaos-reins.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Tested-by: Konstantin Kharlamov <Hi-Angel@yandex.ru>
Tested-by: Shuang Zhai <szhai2@cs.rochester.edu>
Tested-by: Sofia Trinh <sofia.trinh@edi.works>
Tested-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Bug: 228114874
Change-Id: I333ec6a1d2abfa60d93d6adc190ed3eefe441512
2022-05-03 11:10:21 +00:00
Yu Zhao
8936f4eefb BACKPORT: mm: use self-explanatory macros rather than "2"
Signed-off-by: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Link: http://lkml.kernel.org/r/20200831175042.3527153-2-yuzhao@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit ed0173733dd468883198c3136284394320b8fad6)
Bug: 228114874
Change-Id: Ifbc0e8976a29d914ade5a84a8a1fff069cb2d3bb
2022-05-03 11:10:19 +00:00
kondors1995
b20e114357 Merge branch 'android-4.14-stable' of https://android.googlesource.com/kernel/common into 12.1 2022-04-22 14:26:32 +00:00
Greg Kroah-Hartman
b296bf0cb0 Merge 4.14.276 into android-4.14-stable
Changes in 4.14.276
	USB: serial: pl2303: add IBM device IDs
	USB: serial: simple: add Nokia phone driver
	netdevice: add the case if dev is NULL
	virtio_console: break out of buf poll on remove
	ethernet: sun: Free the coherent when failing in probing
	spi: Fix invalid sgs value
	spi: Fix erroneous sgs value with min_t()
	af_key: add __GFP_ZERO flag for compose_sadb_supported in function pfkey_register
	fuse: fix pipe buffer lifetime for direct_io
	tpm: fix reference counting for struct tpm_chip
	block: Add a helper to validate the block size
	virtio-blk: Use blk_validate_block_size() to validate block size
	USB: usb-storage: Fix use of bitfields for hardware data in ene_ub6250.c
	coresight: Fix TRCCONFIGR.QE sysfs interface
	iio: inkern: apply consumer scale on IIO_VAL_INT cases
	iio: inkern: apply consumer scale when no channel scale is available
	iio: inkern: make a best effort on offset calculation
	clk: uniphier: Fix fixed-rate initialization
	ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
	Documentation: add link to stable release candidate tree
	Documentation: update stable tree link
	SUNRPC: avoid race between mod_timer() and del_timer_sync()
	NFSD: prevent underflow in nfssvc_decode_writeargs()
	pinctrl: samsung: drop pin banks references on error paths
	can: ems_usb: ems_usb_start_xmit(): fix double dev_kfree_skb() in error path
	jffs2: fix use-after-free in jffs2_clear_xattr_subsystem
	jffs2: fix memory leak in jffs2_do_mount_fs
	jffs2: fix memory leak in jffs2_scan_medium
	mm/pages_alloc.c: don't create ZONE_MOVABLE beyond the end of a node
	mempolicy: mbind_range() set_policy() after vma_merge()
	scsi: libsas: Fix sas_ata_qc_issue() handling of NCQ NON DATA commands
	qed: display VF trust config
	qed: validate and restrict untrusted VFs vlan promisc mode
	Revert "Input: clear BTN_RIGHT/MIDDLE on buttonpads"
	ALSA: cs4236: fix an incorrect NULL check on list iterator
	drbd: fix potential silent data corruption
	ACPI: properties: Consistently return -ENOENT if there are no more references
	drivers: hamradio: 6pack: fix UAF bug caused by mod_timer()
	video: fbdev: sm712fb: Fix crash in smtcfb_read()
	video: fbdev: atari: Atari 2 bpp (STe) palette bugfix
	ARM: dts: at91: sama5d2: Fix PMERRLOC resource size
	ARM: dts: exynos: fix UART3 pins configuration in Exynos5250
	ARM: dts: exynos: add missing HDMI supplies on SMDK5250
	ARM: dts: exynos: add missing HDMI supplies on SMDK5420
	carl9170: fix missing bit-wise or operator for tx_params
	thermal: int340x: Increase bitmap size
	lib/raid6/test: fix multiple definition linking error
	DEC: Limit PMAX memory probing to R3k systems
	media: davinci: vpif: fix unbalanced runtime PM get
	brcmfmac: firmware: Allocate space for default boardrev in nvram
	brcmfmac: pcie: Replace brcmf_pcie_copy_mem_todev with memcpy_toio
	PCI: pciehp: Clear cmd_busy bit in polling mode
	crypto: authenc - Fix sleep in atomic context in decrypt_tail
	crypto: mxs-dcp - Fix scatterlist processing
	spi: tegra114: Add missing IRQ check in tegra_spi_probe
	selftests/x86: Add validity check and allow field splitting
	spi: pxa2xx-pci: Balance reference count for PCI DMA device
	hwmon: (pmbus) Add mutex to regulator ops
	hwmon: (sch56xx-common) Replace WDOG_ACTIVE with WDOG_HW_RUNNING
	PM: hibernate: fix __setup handler error handling
	PM: suspend: fix return value of __setup handler
	hwrng: atmel - disable trng on failure path
	crypto: vmx - add missing dependencies
	ACPI: APEI: fix return value of __setup handlers
	crypto: ccp - ccp_dmaengine_unregister release dma channels
	hwmon: (pmbus) Add Vin unit off handling
	clocksource: acpi_pm: fix return value of __setup handler
	sched/debug: Remove mpol_get/put and task_lock/unlock from sched_show_numa
	perf/core: Fix address filter parser for multiple filters
	perf/x86/intel/pt: Fix address filter config for 32-bit kernel
	media: coda: Fix missing put_device() call in coda_get_vdoa_data
	video: fbdev: smscufx: Fix null-ptr-deref in ufx_usb_probe()
	video: fbdev: fbcvt.c: fix printing in fb_cvt_print_name()
	ARM: dts: qcom: ipq4019: fix sleep clock
	soc: ti: wkup_m3_ipc: Fix IRQ check in wkup_m3_ipc_probe
	media: usb: go7007: s2250-board: fix leak in probe()
	ASoC: ti: davinci-i2s: Add check for clk_enable()
	ALSA: spi: Add check for clk_enable()
	arm64: dts: ns2: Fix spi-cpol and spi-cpha property
	arm64: dts: broadcom: Fix sata nodename
	printk: fix return value of printk.devkmsg __setup handler
	ASoC: mxs-saif: Handle errors for clk_enable
	ASoC: atmel_ssc_dai: Handle errors for clk_enable
	memory: emif: Add check for setup_interrupts
	memory: emif: check the pointer temp in get_device_details()
	ALSA: firewire-lib: fix uninitialized flag for AV/C deferred transaction
	media: stk1160: If start stream fails, return buffers with VB2_BUF_STATE_QUEUED
	ASoC: atmel: Add missing of_node_put() in at91sam9g20ek_audio_probe
	ASoC: wm8350: Handle error for wm8350_register_irq
	ASoC: fsi: Add check for clk_enable
	video: fbdev: omapfb: Add missing of_node_put() in dvic_probe_of
	ASoC: dmaengine: do not use a NULL prepare_slave_config() callback
	ASoC: mxs: Fix error handling in mxs_sgtl5000_probe
	ASoC: imx-es8328: Fix error return code in imx_es8328_probe()
	ASoC: msm8916-wcd-digital: Fix missing clk_disable_unprepare() in msm8916_wcd_digital_probe
	mtd: onenand: Check for error irq
	drm/edid: Don't clear formats if using deep color
	ath9k_htc: fix uninit value bugs
	power: reset: gemini-poweroff: Fix IRQ check in gemini_poweroff_probe
	ray_cs: Check ioremap return value
	power: supply: ab8500: Fix memory leak in ab8500_fg_sysfs_init
	HID: i2c-hid: fix GET/SET_REPORT for unnumbered reports
	iwlwifi: Fix -EIO error code that is never returned
	dm crypt: fix get_key_size compiler warning if !CONFIG_KEYS
	scsi: pm8001: Fix command initialization in pm80XX_send_read_log()
	scsi: pm8001: Fix command initialization in pm8001_chip_ssp_tm_req()
	scsi: pm8001: Fix payload initialization in pm80xx_set_thermal_config()
	scsi: pm8001: Fix abort all task initialization
	TOMOYO: fix __setup handlers return values
	ext2: correct max file size computing
	drm/tegra: Fix reference leak in tegra_dsi_ganged_probe
	power: supply: bq24190_charger: Fix bq24190_vbus_is_enabled() wrong false return
	KVM: x86: Fix emulation in writing cr8
	KVM: x86/emulator: Defer not-present segment check in __load_segment_descriptor()
	i2c: xiic: Make bus names unique
	power: supply: wm8350-power: Handle error for wm8350_register_irq
	power: supply: wm8350-power: Add missing free in free_charger_irq
	PCI: Reduce warnings on possible RW1C corruption
	powerpc/sysdev: fix incorrect use to determine if list is empty
	mfd: mc13xxx: Add check for mc13xxx_irq_request
	vxcan: enable local echo for sent CAN frames
	MIPS: RB532: fix return value of __setup handler
	mtd: rawnand: atmel: fix refcount issue in atmel_nand_controller_init
	USB: storage: ums-realtek: fix error code in rts51x_read_mem()
	af_netlink: Fix shift out of bounds in group mask calculation
	i2c: mux: demux-pinctrl: do not deactivate a master that is not active
	tcp: ensure PMTU updates are processed during fastopen
	mfd: asic3: Add missing iounmap() on error asic3_mfd_probe
	mxser: fix xmit_buf leak in activate when LSR == 0xff
	pwm: lpc18xx-sct: Initialize driver data and hardware before pwmchip_add()
	staging:iio:adc:ad7280a: Fix handing of device address bit reversing.
	serial: 8250_mid: Balance reference count for PCI DMA device
	serial: 8250: Fix race condition in RTS-after-send handling
	iio: adc: Add check for devm_request_threaded_irq
	clk: qcom: clk-rcg2: Update the frac table for pixel clock
	remoteproc: qcom_wcnss: Add missing of_node_put() in wcnss_alloc_memory_region
	clk: loongson1: Terminate clk_div_table with sentinel element
	clk: clps711x: Terminate clk_div_table with sentinel element
	clk: tegra: tegra124-emc: Fix missing put_device() call in emc_ensure_emc_driver
	NFS: remove unneeded check in decode_devicenotify_args()
	pinctrl: mediatek: Fix missing of_node_put() in mtk_pctrl_init
	pinctrl: nomadik: Add missing of_node_put() in nmk_pinctrl_probe
	pinctrl/rockchip: Add missing of_node_put() in rockchip_pinctrl_probe
	tty: hvc: fix return value of __setup handler
	kgdboc: fix return value of __setup handler
	kgdbts: fix return value of __setup handler
	jfs: fix divide error in dbNextAG
	netfilter: nf_conntrack_tcp: preserve liberal flag in tcp options
	xen: fix is_xen_pmu()
	net: phy: broadcom: Fix brcm_fet_config_init()
	qlcnic: dcb: default to returning -EOPNOTSUPP
	net/x25: Fix null-ptr-deref caused by x25_disconnect
	NFSv4/pNFS: Fix another issue with a list iterator pointing to the head
	lib/test: use after free in register_test_dev_kmod()
	selinux: use correct type for context length
	loop: use sysfs_emit() in the sysfs xxx show()
	Fix incorrect type in assignment of ipv6 port for audit
	irqchip/nvic: Release nvic_base upon failure
	ACPICA: Avoid walking the ACPI Namespace if it is not there
	ACPI/APEI: Limit printable size of BERT table data
	PM: core: keep irq flags in device_pm_check_callbacks()
	spi: tegra20: Use of_device_get_match_data()
	ext4: don't BUG if someone dirty pages without asking ext4 first
	ntfs: add sanity check on allocation size
	video: fbdev: nvidiafb: Use strscpy() to prevent buffer overflow
	video: fbdev: w100fb: Reset global state
	video: fbdev: cirrusfb: check pixclock to avoid divide by zero
	video: fbdev: omapfb: acx565akm: replace snprintf with sysfs_emit
	ARM: dts: qcom: fix gic_irq_domain_translate warnings for msm8960
	ARM: dts: bcm2837: Add the missing L1/L2 cache information
	video: fbdev: omapfb: panel-dsi-cm: Use sysfs_emit() instead of snprintf()
	video: fbdev: omapfb: panel-tpo-td043mtea1: Use sysfs_emit() instead of snprintf()
	ASoC: soc-core: skip zero num_dai component in searching dai name
	media: cx88-mpeg: clear interrupt status register before streaming video
	ARM: tegra: tamonten: Fix I2C3 pad setting
	ARM: mmp: Fix failure to remove sram device
	video: fbdev: sm712fb: Fix crash in smtcfb_write()
	media: hdpvr: initialize dev->worker at hdpvr_register_videodev
	mmc: host: Return an error when ->enable_sdio_irq() ops is missing
	powerpc/lib/sstep: Fix 'sthcx' instruction
	powerpc/lib/sstep: Fix build errors with newer binutils
	scsi: qla2xxx: Fix warning for missing error code
	scsi: qla2xxx: Suppress a kernel complaint in qla_create_qpair()
	KVM: Prevent module exit until all VMs are freed
	ubifs: rename_whiteout: Fix double free for whiteout_ui->data
	ubifs: Add missing iput if do_tmpfile() failed in rename whiteout
	ubifs: setflags: Make dirtied_ino_d 8 bytes aligned
	ubifs: rename_whiteout: correct old_dir size computing
	can: mcba_usb: mcba_usb_start_xmit(): fix double dev_kfree_skb in error path
	can: mcba_usb: properly check endpoint type
	gfs2: Make sure FITRIM minlen is rounded up to fs block size
	pinctrl: pinconf-generic: Print arguments for bias-pull-*
	ubi: Fix race condition between ctrl_cdev_ioctl and ubi_cdev_ioctl
	ACPI: CPPC: Avoid out of bounds access when parsing _CPC data
	mm/mmap: return 1 from stack_guard_gap __setup() handler
	mm/memcontrol: return 1 from cgroup.memory __setup() handler
	ubi: fastmap: Return error code if memory allocation fails in add_aeb()
	ASoC: topology: Allow TLV control to be either read or write
	ARM: dts: spear1340: Update serial node properties
	ARM: dts: spear13xx: Update SPI dma properties
	openvswitch: Fixed nd target mask field in the flow dump.
	KVM: x86: Forbid VMM to set SYNIC/STIMER MSRs when SynIC wasn't activated
	ubifs: Rectify space amount budget for mkdir/tmpfile operations
	rtc: wm8350: Handle error for wm8350_register_irq
	ARM: 9187/1: JIVE: fix return value of __setup handler
	KVM: x86/svm: Clear reserved bits written to PerfEvtSeln MSRs
	ath5k: fix OOB in ath5k_eeprom_read_pcal_info_5111
	ptp: replace snprintf with sysfs_emit
	powerpc: dts: t104xrdb: fix phy type for FMAN 4/5
	scsi: mvsas: Replace snprintf() with sysfs_emit()
	scsi: bfa: Replace snprintf() with sysfs_emit()
	power: supply: axp20x_battery: properly report current when discharging
	powerpc: Set crashkernel offset to mid of RMA region
	PCI: aardvark: Fix support for MSI interrupts
	iommu/arm-smmu-v3: fix event handling soft lockup
	dm ioctl: prevent potential spectre v1 gadget
	scsi: pm8001: Fix pm8001_mpi_task_abort_resp()
	scsi: aha152x: Fix aha152x_setup() __setup handler return value
	net/smc: correct settings of RMB window update limit
	macvtap: advertise link netns via netlink
	bnxt_en: Eliminate unintended link toggle during FW reset
	MIPS: fix fortify panic when copying asm exception handlers
	scsi: libfc: Fix use after free in fc_exch_abts_resp()
	usb: dwc3: omap: fix "unbalanced disables for smps10_out1" on omap5evm
	xtensa: fix DTC warning unit_address_format
	Bluetooth: Fix use after free in hci_send_acl
	init/main.c: return 1 from handled __setup() functions
	w1: w1_therm: fixes w1_seq for ds28ea00 sensors
	SUNRPC/call_alloc: async tasks mustn't block waiting for memory
	NFS: swap IO handling is slightly different for O_DIRECT IO
	NFS: swap-out must always use STABLE writes.
	serial: samsung_tty: do not unlock port->lock for uart_write_wakeup()
	virtio_console: eliminate anonymous module_init & module_exit
	jfs: prevent NULL deref in diFree
	parisc: Fix CPU affinity for Lasi, WAX and Dino chips
	ipv6: add missing tx timestamping on IPPROTO_RAW
	net: add missing SOF_TIMESTAMPING_OPT_ID support
	mm: fix race between MADV_FREE reclaim and blkdev direct IO read
	drm/amdgpu: fix off by one in amdgpu_gfx_kiq_acquire()
	scsi: zorro7xx: Fix a resource leak in zorro7xx_remove_one()
	net: stmmac: Fix unset max_speed difference between DT and non-DT platforms
	drm/imx: Fix memory leak in imx_pd_connector_get_modes
	drbd: Fix five use after free bugs in get_initial_state
	Revert "mmc: sdhci-xenon: fix annoying 1.8V regulator warning"
	mmmremap.c: avoid pointless invalidate_range_start/end on mremap(old_size=0)
	mm/mempolicy: fix mpol_new leak in shared_policy_replace
	x86/pm: Save the MSR validity status at context setup
	x86/speculation: Restore speculation related MSRs during S3 resume
	btrfs: fix qgroup reserve overflow the qgroup limit
	arm64: patch_text: Fixup last cpu should be master
	perf: qcom_l2_pmu: fix an incorrect NULL check on list iterator
	tools build: Use $(shell ) instead of `` to get embedded libperl's ccopts
	dmaengine: Revert "dmaengine: shdma: Fix runtime PM imbalance on error"
	mm: don't skip swap entry even if zap_details specified
	arm64: module: remove (NOLOAD) from linker script
	mm/sparsemem: fix 'mem_section' will never be NULL gcc 12 warning
	cgroup: Use open-time credentials for process migraton perm checks
	cgroup: Allocate cgroup_file_ctx for kernfs_open_file->priv
	cgroup: Use open-time cgroup namespace for process migration perm checks
	xfrm: policy: match with both mark and mask on user interfaces
	memory: atmel-ebi: Fix missing of_node_put in atmel_ebi_probe
	veth: Ensure eth header is in skb's linear part
	gpiolib: acpi: use correct format characters
	mlxsw: i2c: Fix initialization error flow
	net: ethernet: stmmac: fix altr_tse_pcs function when using a fixed-link
	nfc: nci: add flush_workqueue to prevent uaf
	cifs: potential buffer overflow in handling symlinks
	drm/amd: Add USBC connector ID
	drm/amdkfd: Check for potential null return of kmalloc_array()
	Drivers: hv: vmbus: Prevent load re-ordering when reading ring buffer
	scsi: target: tcmu: Fix possible page UAF
	scsi: ibmvscsis: Increase INITIAL_SRP_LIMIT to 1024
	net: micrel: fix KS8851_MLL Kconfig
	ata: libata-core: Disable READ LOG DMA EXT for Samsung 840 EVOs
	gpu: ipu-v3: Fix dev_dbg frequency output
	scsi: mvsas: Add PCI ID of RocketRaid 2640
	drivers: net: slip: fix NPD bug in sl_tx_timeout()
	mm, page_alloc: fix build_zonerefs_node()
	mm: kmemleak: take a full lowmem check in kmemleak_*_phys()
	gcc-plugins: latent_entropy: use /dev/urandom
	ALSA: pcm: Test for "silence" field in struct "pcm_format_data"
	ARM: davinci: da850-evm: Avoid NULL pointer dereference
	smp: Fix offline cpu check in flush_smp_call_function_queue()
	i2c: pasemi: Wait for write xfers to finish
	Linux 4.14.276

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: I45d8292ce654c0236758030a89b4618cf3a3d87b
2022-04-21 14:08:46 +02:00
Waiman Long
45ac758ee0 mm/sparsemem: fix 'mem_section' will never be NULL gcc 12 warning
commit a431dbbc540532b7465eae4fc8b56a85a9fc7d17 upstream.

The gcc 12 compiler reports a "'mem_section' will never be NULL" warning
on the following code:

    static inline struct mem_section *__nr_to_section(unsigned long nr)
    {
    #ifdef CONFIG_SPARSEMEM_EXTREME
        if (!mem_section)
                return NULL;
    #endif
        if (!mem_section[SECTION_NR_TO_ROOT(nr)])
                return NULL;
       :

It happens with CONFIG_SPARSEMEM_EXTREME off.  The mem_section definition
is

    #ifdef CONFIG_SPARSEMEM_EXTREME
    extern struct mem_section **mem_section;
    #else
    extern struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT];
    #endif

In the !CONFIG_SPARSEMEM_EXTREME case, mem_section is a static
2-dimensional array and so the check "!mem_section[SECTION_NR_TO_ROOT(nr)]"
doesn't make sense.

Fix this warning by moving the "!mem_section[SECTION_NR_TO_ROOT(nr)]"
check up inside the CONFIG_SPARSEMEM_EXTREME block and adding an
explicit NR_SECTION_ROOTS check to make sure that there is no
out-of-bound array access.

Link: https://lkml.kernel.org/r/20220331180246.2746210-1-longman@redhat.com
Fixes: 3e347261a8 ("sparsemem extreme implementation")
Signed-off-by: Waiman Long <longman@redhat.com>
Reported-by: Justin Forbes <jforbes@redhat.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Rafael Aquini <aquini@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-20 09:08:30 +02:00
Wei Yang
77606b9dee mm: fix some typos in mm directory
No functional change.

Link: http://lkml.kernel.org/r/20190118235123.27843-1-richard.weiyang@gmail.com
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Park Ju Hyung <qkrwngud825@gmail.com>
Signed-off-by: Alex Winkowski <dereference23@outlook.com>
2022-04-11 08:52:34 +00:00
Sultan Alsawaf
0ee45bc186 mm: Move slab shrinkers into a dedicated thread called kshrinkd
Slab shrinkers are unique in that they have no bearing on direct reclaim
throttling and reclaim statistics, meaning that they can be completely
decoupled from the kswapd and direct reclaim paths, making them faster.
Further justification for this is that shrinkers may be slow and aren't
guaranteed to free any memory, which means that they can waste kswapd
and direct reclaim time without producing results. Running the same
shrinker concurrently can also produce unwanted lock contention inside
the shrinker itself.

An empirical test of checking how long kswapd and kshrinkd ran on a
memory constrained system showed that kshrinkd ran for about 10% of the
duration that kswapd ran, which indicates significant savings.

Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
2021-10-20 22:10:43 +00:00
Sultan Alsawaf
b06293b21b mm: Don't stop kswapd on a per-node basis when there are no waiters
The page allocator wakes all kswapds in an allocation context's allowed
nodemask in the slow path, so it doesn't make sense to have the kswapd-
waiter count per each NUMA node. Instead, it should be a global counter
to stop all kswapds when there are no failed allocation requests.

Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
2021-04-26 10:04:49 +00:00
Sultan Alsawaf
dbcceea7c6 mm: Stop kswapd early when nothing's waiting for it to free pages
Keeping kswapd running when all the failed allocations that invoked it
are satisfied incurs a high overhead due to unnecessary page eviction
and writeback, as well as spurious VM pressure events to various
registered shrinkers. When kswapd doesn't need to work to make an
allocation succeed anymore, stop it prematurely to save resources.

Signed-off-by: Sultan Alsawaf <sultan@kerneltoast.com>
2021-04-26 10:04:49 +00:00
Srinivasarao P
8241b06f7c Merge android-4.14.159 (f960b38) into msm-4.14
* refs/heads/tmp-f960b38:
  Linux 4.14.159
  of: unittest: fix memory leak in attach_node_and_children
  raid5: need to set STRIPE_HANDLE for batch head
  gpiolib: acpi: Add Terra Pad 1061 to the run_edge_events_on_boot_blacklist
  kernel/module.c: wakeup processes in module_wq on module unload
  gfs2: fix glock reference problem in gfs2_trans_remove_revoke
  net/mlx5e: Fix SFF 8472 eeprom length
  sunrpc: fix crash when cache_head become valid before update
  workqueue: Fix missing kfree(rescuer) in destroy_workqueue()
  blk-mq: make sure that line break can be printed
  mfd: rk808: Fix RK818 ID template
  ext4: fix a bug in ext4_wait_for_tail_page_commit
  mm/shmem.c: cast the type of unmap_start to u64
  firmware: qcom: scm: Ensure 'a0' status code is treated as signed
  ext4: work around deleting a file with i_nlink == 0 safely
  powerpc: Fix vDSO clock_getres()
  powerpc: Avoid clang warnings around setjmp and longjmp
  ath10k: fix fw crash by moving chip reset after napi disabled
  media: vimc: fix component match compare
  mlxsw: spectrum_router: Refresh nexthop neighbour when it becomes dead
  power: supply: cpcap-battery: Fix signed counter sample register
  x86/MCE/AMD: Carve out the MC4_MISC thresholding quirk
  x86/MCE/AMD: Turn off MC4_MISC thresholding on all family 0x15 models
  e100: Fix passing zero to 'PTR_ERR' warning in e100_load_ucode_wait
  drbd: Change drbd_request_detach_interruptible's return type to int
  scsi: lpfc: Correct code setting non existent bits in sli4 ABORT WQE
  scsi: lpfc: Cap NPIV vports to 256
  omap: pdata-quirks: remove openpandora quirks for mmc3 and wl1251
  phy: renesas: rcar-gen3-usb2: Fix sysfs interface of "role"
  iio: adis16480: Add debugfs_reg_access entry
  xhci: make sure interrupts are restored to correct state
  xhci: Fix memory leak in xhci_add_in_port()
  scsi: qla2xxx: Fix message indicating vectors used by driver
  scsi: qla2xxx: Always check the qla2x00_wait_for_hba_online() return value
  scsi: qla2xxx: Fix qla24xx_process_bidir_cmd()
  scsi: qla2xxx: Fix session lookup in qlt_abort_work()
  scsi: qla2xxx: Fix DMA unmap leak
  scsi: zfcp: trace channel log even for FCP command responses
  block: fix single range discard merge
  reiserfs: fix extended attributes on the root directory
  ext4: Fix credit estimate for final inode freeing
  quota: fix livelock in dquot_writeback_dquots
  ext2: check err when partial != NULL
  quota: Check that quota is not dirty before release
  video/hdmi: Fix AVI bar unpack
  powerpc/xive: Skip ioremap() of ESB pages for LSI interrupts
  powerpc: Allow flush_icache_range to work across ranges >4GB
  powerpc/xive: Prevent page fault issues in the machine crash handler
  powerpc: Allow 64bit VDSO __kernel_sync_dicache to work across ranges >4GB
  ppdev: fix PPGETTIME/PPSETTIME ioctls
  ARM: dts: omap3-tao3530: Fix incorrect MMC card detection GPIO polarity
  mmc: host: omap_hsmmc: add code for special init of wl1251 to get rid of pandora_wl1251_init_card
  pinctrl: samsung: Fix device node refcount leaks in S3C64xx wakeup controller init
  pinctrl: samsung: Fix device node refcount leaks in init code
  pinctrl: samsung: Fix device node refcount leaks in S3C24xx wakeup controller init
  pinctrl: samsung: Add of_node_put() before return in error path
  ACPI: PM: Avoid attaching ACPI PM domain to certain devices
  ACPI: bus: Fix NULL pointer check in acpi_bus_get_private_data()
  ACPI: OSL: only free map once in osl.c
  cpufreq: powernv: fix stack bloat and hard limit on number of CPUs
  PM / devfreq: Lock devfreq in trans_stat_show
  intel_th: pci: Add Tiger Lake CPU support
  intel_th: pci: Add Ice Lake CPU support
  intel_th: Fix a double put_device() in error path
  cpuidle: Do not unset the driver if it is there already
  media: cec.h: CEC_OP_REC_FLAG_ values were swapped
  media: radio: wl1273: fix interrupt masking on release
  media: bdisp: fix memleak on release
  s390/mm: properly clear _PAGE_NOEXEC bit when it is not supported
  ar5523: check NULL before memcpy() in ar5523_cmd()
  cgroup: pids: use atomic64_t for pids->limit
  blk-mq: avoid sysfs buffer overflow with too many CPU cores
  ASoC: Jack: Fix NULL pointer dereference in snd_soc_jack_report
  workqueue: Fix pwq ref leak in rescuer_thread()
  workqueue: Fix spurious sanity check failures in destroy_workqueue()
  dm zoned: reduce overhead of backing device checks
  hwrng: omap - Fix RNG wait loop timeout
  watchdog: aspeed: Fix clock behaviour for ast2600
  md/raid0: Fix an error message in raid0_make_request()
  ALSA: hda - Fix pending unsol events at shutdown
  ovl: relax WARN_ON() on rename to self
  lib: raid6: fix awk build warnings
  rtlwifi: rtl8192de: Fix missing enable interrupt flag
  rtlwifi: rtl8192de: Fix missing callback that tests for hw release of buffer
  rtlwifi: rtl8192de: Fix missing code to retrieve RX buffer address
  btrfs: record all roots for rename exchange on a subvol
  Btrfs: send, skip backreference walking for extents with many references
  btrfs: Remove btrfs_bio::flags member
  Btrfs: fix negative subv_writers counter and data space leak after buffered write
  btrfs: use refcount_inc_not_zero in kill_all_nodes
  btrfs: check page->mapping when loading free space cache
  usb: dwc3: ep0: Clear started flag on completion
  virtio-balloon: fix managed page counts when migrating pages between zones
  mtd: spear_smi: Fix Write Burst mode
  tpm: add check after commands attribs tab allocation
  usb: mon: Fix a deadlock in usbmon between mmap and read
  usb: core: urb: fix URB structure initialization function
  USB: adutux: fix interface sanity check
  USB: serial: io_edgeport: fix epic endpoint lookup
  USB: idmouse: fix interface sanity checks
  USB: atm: ueagle-atm: add missing endpoint check
  iio: humidity: hdc100x: fix IIO_HUMIDITYRELATIVE channel reporting
  ARM: dts: pandora-common: define wl1251 as child node of mmc3
  xhci: handle some XHCI_TRUST_TX_LENGTH quirks cases as default behaviour.
  xhci: Increase STS_HALT timeout in xhci_suspend()
  usb: xhci: only set D3hot for pci device
  staging: gigaset: add endpoint-type sanity check
  staging: gigaset: fix illegal free on probe errors
  staging: gigaset: fix general protection fault on probe
  staging: rtl8712: fix interface sanity check
  staging: rtl8188eu: fix interface sanity check
  usb: Allow USB device to be warm reset in suspended state
  USB: documentation: flags on usb-storage versus UAS
  USB: uas: heed CAPACITY_HEURISTICS
  USB: uas: honor flag to avoid CAPACITY16
  media: venus: remove invalid compat_ioctl32 handler
  scsi: qla2xxx: Fix driver unload hang
  usb: gadget: pch_udc: fix use after free
  usb: gadget: configfs: Fix missing spin_lock_init()
  appletalk: Set error code if register_snap_client failed
  appletalk: Fix potential NULL pointer dereference in unregister_snap_client
  KVM: x86: fix out-of-bounds write in KVM_GET_EMULATED_CPUID (CVE-2019-19332)
  ASoC: rsnd: fixup MIX kctrl registration
  binder: Handle start==NULL in binder_update_page_range()
  thermal: Fix deadlock in thermal thermal_zone_device_check
  iomap: Fix pipe page leakage during splicing
  RDMA/qib: Validate ->show()/store() callbacks before calling them
  spi: atmel: Fix CS high support
  crypto: user - fix memory leak in crypto_report
  crypto: ecdh - fix big endian bug in ECC library
  crypto: ccp - fix uninitialized list head
  crypto: af_alg - cast ki_complete ternary op to int
  crypto: crypto4xx - fix double-free in crypto4xx_destroy_sdr
  KVM: x86: fix presentation of TSX feature in ARCH_CAPABILITIES
  KVM: x86: do not modify masked bits of shared MSRs
  KVM: arm/arm64: vgic: Don't rely on the wrong pending table
  drm/i810: Prevent underflow in ioctl
  jbd2: Fix possible overflow in jbd2_log_space_left()
  kernfs: fix ino wrap-around detection
  can: slcan: Fix use-after-free Read in slcan_open
  tty: vt: keyboard: reject invalid keycodes
  CIFS: Fix SMB2 oplock break processing
  CIFS: Fix NULL-pointer dereference in smb2_push_mandatory_locks
  x86/PCI: Avoid AMD FCH XHCI USB PME# from D0 defect
  Input: Fix memory leak in psxpad_spi_probe
  coresight: etm4x: Fix input validation for sysfs.
  Input: goodix - add upside-down quirk for Teclast X89 tablet
  Input: synaptics-rmi4 - don't increment rmiaddr for SMBus transfers
  Input: synaptics-rmi4 - re-enable IRQs in f34v7_do_reflash
  Input: synaptics - switch another X1 Carbon 6 to RMI/SMbus
  ALSA: hda - Add mute led support for HP ProBook 645 G4
  ALSA: pcm: oss: Avoid potential buffer overflows
  ALSA: hda/realtek - Dell headphone has noise on unmute for ALC236
  fuse: verify attributes
  fuse: verify nlink
  sched/fair: Scale bandwidth quota and period without losing quota/period ratio precision
  tcp: exit if nothing to retransmit on RTO timeout
  net: aquantia: fix RSS table and key sizes
  media: vimc: fix start stream when link is disabled
  ARM: dts: sunxi: Fix PMU compatible strings
  usb: mtu3: fix dbginfo in qmu_tx_zlp_error_handler
  mlx4: Use snprintf instead of complicated strcpy
  IB/hfi1: Close VNIC sdma_progress sleep window
  IB/hfi1: Ignore LNI errors before DC8051 transitions to Polling state
  mlxsw: spectrum_router: Relax GRE decap matching check
  firmware: qcom: scm: fix compilation error when disabled
  media: stkwebcam: Bugfix for wrong return values
  tty: Don't block on IO when ldisc change is pending
  nfsd: Return EPERM, not EACCES, in some SETATTR cases
  MIPS: OCTEON: cvmx_pko_mem_debug8: use oldest forward compatible definition
  clk: renesas: r8a77995: Correct parent clock of DU
  powerpc/math-emu: Update macros from GCC
  pstore/ram: Avoid NULL deref in ftrace merging failure path
  net/mlx4_core: Fix return codes of unsupported operations
  dlm: fix invalid cluster name warning
  ARM: dts: realview: Fix some more duplicate regulator nodes
  clk: sunxi-ng: h3/h5: Fix CSI_MCLK parent
  ARM: dts: pxa: clean up USB controller nodes
  mtd: fix mtd_oobavail() incoherent returned value
  kbuild: fix single target build for external module
  modpost: skip ELF local symbols during section mismatch check
  tcp: fix SNMP TCP timeout under-estimation
  tcp: fix SNMP under-estimation on failed retransmission
  tcp: fix off-by-one bug on aborting window-probing socket
  ARM: dts: realview-pbx: Fix duplicate regulator nodes
  ARM: dts: mmp2: fix the gpio interrupt cell number
  net/x25: fix null_x25_address handling
  net/x25: fix called/calling length calculation in x25_parse_address_block
  arm64: dts: meson-gxl-khadas-vim: fix GPIO lines names
  arm64: dts: meson-gxbb-odroidc2: fix GPIO lines names
  arm64: dts: meson-gxbb-nanopi-k2: fix GPIO lines names
  arm64: dts: meson-gxl-libretech-cc: fix GPIO lines names
  ARM: OMAP1/2: fix SoC name printing
  ASoC: au8540: use 64-bit arithmetic instead of 32-bit
  nfsd: fix a warning in __cld_pipe_upcall()
  ARM: debug: enable UART1 for socfpga Cyclone5
  dlm: NULL check before kmem_cache_destroy is not needed
  ARM: dts: sun8i: v3s: Change pinctrl nodes to avoid warning
  ARM: dts: sun5i: a10s: Fix HDMI output DTC warning
  ASoC: rsnd: tidyup registering method for rsnd_kctrl_new()
  lockd: fix decoding of TEST results
  i2c: imx: don't print error message on probe defer
  serial: imx: fix error handling in console_setup
  altera-stapl: check for a null key before strcasecmp'ing it
  dma-mapping: fix return type of dma_set_max_seg_size()
  sparc: Correct ctx->saw_frame_pointer logic.
  f2fs: fix to allow node segment for GC by ioctl path
  ARM: dts: rockchip: Assign the proper GPIO clocks for rv1108
  ARM: dts: rockchip: Fix the PMU interrupt number for rv1108
  f2fs: change segment to section in f2fs_ioc_gc_range
  f2fs: fix count of seg_freed to make sec_freed correct
  ACPI: fix acpi_find_child_device() invocation in acpi_preset_companion()
  usb: dwc3: don't log probe deferrals; but do log other error codes
  usb: dwc3: debugfs: Properly print/set link state for HS
  dmaengine: dw-dmac: implement dma protection control setting
  dmaengine: coh901318: Remove unused variable
  dmaengine: coh901318: Fix a double-lock bug
  media: cec: report Vendor ID after initialization
  media: pulse8-cec: return 0 when invalidating the logical address
  ARM: dts: exynos: Use Samsung SoC specific compatible for DWC2 module
  rtc: dt-binding: abx80x: fix resistance scale
  rtc: max8997: Fix the returned value in case of error in 'max8997_rtc_read_alarm()'
  math-emu/soft-fp.h: (_FP_ROUND_ZERO) cast 0 to void to fix warning
  net/smc: use after free fix in smc_wr_tx_put_slot()
  MIPS: OCTEON: octeon-platform: fix typing
  iomap: sub-block dio needs to zeroout beyond EOF
  net-next/hinic:fix a bug in set mac address
  regulator: Fix return value of _set_load() stub
  clk: rockchip: fix ID of 8ch clock of I2S1 for rk3328
  clk: rockchip: fix I2S1 clock gate register for rk3328
  mm/vmstat.c: fix NUMA statistics updates
  Staging: iio: adt7316: Fix i2c data reading, set the data field
  pinctrl: qcom: ssbi-gpio: fix gpio-hog related boot issues
  crypto: bcm - fix normal/non key hash algorithm failure
  crypto: ecc - check for invalid values in the key verification test
  scsi: zfcp: drop default switch case which might paper over missing case
  net: dsa: mv88e6xxx: Work around mv886e6161 SERDES missing MII_PHYSID2
  MIPS: SiByte: Enable ZONE_DMA32 for LittleSur
  dlm: fix missing idr_destroy for recover_idr
  ARM: dts: rockchip: Fix rk3288-rock2 vcc_flash name
  clk: rockchip: fix rk3188 sclk_mac_lbtest parameter ordering
  clk: rockchip: fix rk3188 sclk_smc gate data
  i40e: don't restart nway if autoneg not supported
  rtc: s3c-rtc: Avoid using broken ALMYEAR register
  net: ethernet: ti: cpts: correct debug for expired txq skb
  extcon: max8997: Fix lack of path setting in USB device mode
  dlm: fix possible call to kfree() for non-initialized pointer
  clk: sunxi-ng: a64: Fix gate bit of DSI DPHY
  net/mlx5: Release resource on error flow
  ARM: 8813/1: Make aligned 2-byte getuser()/putuser() atomic on ARMv6+
  iwlwifi: mvm: Send non offchannel traffic via AP sta
  iwlwifi: mvm: synchronize TID queue removal
  cxgb4vf: fix memleak in mac_hlist initialization
  serial: core: Allow processing sysrq at port unlock time
  i2c: core: fix use after free in of_i2c_notify
  net: ep93xx_eth: fix mismatch of request_mem_region in remove
  rsxx: add missed destroy_workqueue calls in remove
  ALSA: pcm: Fix stream lock usage in snd_pcm_period_elapsed()
  sched/core: Avoid spurious lock dependencies
  Input: cyttsp4_core - fix use after free bug
  xfrm: release device reference for invalid state
  NFC: nxp-nci: Fix NULL pointer dereference after I2C communication error
  audit_get_nd(): don't unlock parent too early
  exportfs_decode_fh(): negative pinned may become positive without the parent locked
  iwlwifi: pcie: don't consider IV len in A-MSDU
  RDMA/hns: Correct the value of HNS_ROCE_HEM_CHUNK_LEN
  autofs: fix a leak in autofs_expire_indirect()
  serial: ifx6x60: add missed pm_runtime_disable
  serial: serial_core: Perform NULL checks for break_ctl ops
  serial: pl011: Fix DMA ->flush_buffer()
  tty: serial: msm_serial: Fix flow control
  tty: serial: fsl_lpuart: use the sg count from dma_map_sg
  usb: gadget: u_serial: add missing port entry locking
  arm64: tegra: Fix 'active-low' warning for Jetson TX1 regulator
  rsi: release skb if rsi_prepare_beacon fails
  ANDROID: staging: android: ion: Fix build when CONFIG_ION_SYSTEM_HEAP=n
  ANDROID: staging: android: ion: Expose total heap and pool sizes via sysfs
  UPSTREAM: include/linux/slab.h: fix sparse warning in kmalloc_type()
  UPSTREAM: mm, slab: shorten kmalloc cache names for large sizes
  UPSTREAM: mm, proc: add KReclaimable to /proc/meminfo
  BACKPORT: mm: rename and change semantics of nr_indirectly_reclaimable_bytes
  UPSTREAM: dcache: allocate external names from reclaimable kmalloc caches
  BACKPORT: mm, slab/slub: introduce kmalloc-reclaimable caches
  UPSTREAM: mm, slab: combine kmalloc_caches and kmalloc_dma_caches
  ANDROID: kbuild: disable SCS by default in allmodconfig
  ANDROID: arm64: cuttlefish_defconfig: enable LTO, CFI, and SCS
  BACKPORT: FROMLIST: arm64: implement Shadow Call Stack
  FROMLIST: arm64: disable SCS for hypervisor code
  BACKPORT: FROMLIST: arm64: vdso: disable Shadow Call Stack
  FROMLIST: arm64: preserve x18 when CPU is suspended
  FROMLIST: arm64: reserve x18 from general allocation with SCS
  FROMLIST: arm64: disable function graph tracing with SCS
  FROMLIST: scs: add support for stack usage debugging
  FROMLIST: scs: add accounting
  FROMLIST: add support for Clang's Shadow Call Stack (SCS)
  FROMLIST: arm64: kernel: avoid x18 in __cpu_soft_restart
  FROMLIST: arm64: kvm: stop treating register x18 as caller save
  FROMLIST: arm64/lib: copy_page: avoid x18 register in assembler code
  FROMLIST: arm64: mm: avoid x18 in idmap_kpti_install_ng_mappings
  ANDROID: use non-canonical CFI jump tables
  ANDROID: arm64: add __nocfi to __apply_alternatives
  ANDROID: arm64: add __pa_function
  ANDROID: arm64: allow ThinLTO to be selected
  ANDROID: soc/tegra: disable ARCH_TEGRA_210_SOC with LTO
  FROMLIST: arm64: fix alternatives with LLVM's integrated assembler
  ANDROID: irqchip/gic-v3: rename gic_of_init to work around a ThinLTO+CFI bug
  ANDROID: kbuild: limit LTO inlining
  ANDROID: kbuild: merge module sections with LTO
  ANDROID: init: ensure initcall ordering with LTO
  Revert "ANDROID: HACK: init: ensure initcall ordering with LTO"
  ANDROID: add support for ThinLTO
  ANDROID: Switch to LLD
  ANDROID: clang: update to 10.0.1
  ANDROID: arm64: add atomic_ll_sc.o to obj-y if using lld
  ANDROID: enable ARM64_ERRATUM_843419 by default with LTO_CLANG
  ANDROID: kbuild: allow lld to be used with CONFIG_LTO_CLANG
  ANDROID: Makefile: set -Qunused-arguments sooner
  BACKPORT: FROMLIST: Makefile: lld: tell clang to use lld
  BACKPORT: FROMLIST: Makefile: lld: set -O2 linker flag when linking with LLD
  ANDROID: scripts/Kbuild: add ld-name support for ld.lld
  UPSTREAM: bpf: permit multiple bpf attachments for a single perf event
  UPSTREAM: bpf: use the same condition in perf event set/free bpf handler
  UPSTREAM: bpf: multi program support for cgroup+bpf
  BACKPORT: serdev: make synchronous write return bytes written
  UPSTREAM: gnss: serial: fix synchronous write timeout
  UPSTREAM: gnss: fix potential error pointer dereference
  BACKPORT: gnss: add receiver type support
  UPSTREAM: dt-bindings: add generic gnss binding
  UPSTREAM: gnss: add generic serial driver
  ANDROID: cuttlefish_defconfig: Enable CONFIG_SERIAL_DEV_BUS
  ANDROID: cuttlefish_defconfig: Enable CONFIG_GNSS
  BACKPORT: gnss: add GNSS receiver subsystem
  UPSTREAM: arm64: Validate tagged addresses in access_ok() called from kernel threads
  BACKPORT: ARM: 8905/1: Emit __gnu_mcount_nc when using Clang 10.0.0 or newer
  fs/lock: skip lock owner pid translation in case we are in init_pid_ns
  f2fs: stop GC when the victim becomes fully valid
  f2fs: expose main_blkaddr in sysfs
  f2fs: choose hardlimit when softlimit is larger than hardlimit in f2fs_statfs_project()
  f2fs: Fix deadlock in f2fs_gc() context during atomic files handling
  f2fs: show f2fs instance in printk_ratelimited
  f2fs: fix potential overflow
  f2fs: fix to update dir's i_pino during cross_rename
  f2fs: support aligned pinned file
  f2fs: avoid kernel panic on corruption test
  f2fs: fix wrong description in document
  f2fs: cache global IPU bio
  f2fs: fix to avoid memory leakage in f2fs_listxattr
  f2fs: check total_segments from devices in raw_super
  f2fs: update multi-dev metadata in resize_fs
  f2fs: mark recovery flag correctly in read_raw_super_block()
  f2fs: fix to update time in lazytime mode
  vfs: don't allow writes to swap files
  mm: set S_SWAPFILE on blockdev swap devices

Conflicts:
	drivers/Makefile
	drivers/staging/android/ion/ion.c
	drivers/staging/android/ion/ion.h
	drivers/staging/android/ion/ion_page_pool.c
	drivers/usb/dwc3/core.c
	drivers/usb/dwc3/debugfs.c
	drivers/usb/dwc3/ep0.c
	fs/f2fs/data.c
	include/linux/mmzone.h
	mm/vmstat.c

Discarded below patches, as usb patches not applicable and block patch
causing stability issues:
	usb: dwc3: ep0: Clear started flag on completion
	usb: dwc3: don't log probe deferrals; but do log other error codes
	block: fix single range discard merge

Fixed build errors in below files:
	drivers/gpu/msm/kgsl_pool.c
	drivers/staging/android/ion/ion_page_pool.c
	kernel/taskstats.c

Fixed bootup issue in:
	arch/arm64/mm/proc.s

Change-Id: I0a16824c251c14c63af78f9cfd9ede5e82c427fc
Signed-off-by: Srinivasarao P <spathi@codeaurora.org>
Signed-off-by: Blagovest Kolenichev <bkolenichev@codeaurora.org>
2020-04-17 17:47:52 +05:30
Vlastimil Babka
7ca01d96f4 BACKPORT: mm: rename and change semantics of nr_indirectly_reclaimable_bytes
The vmstat counter NR_INDIRECTLY_RECLAIMABLE_BYTES was introduced by
commit eb59254608bc ("mm: introduce NR_INDIRECTLY_RECLAIMABLE_BYTES") with
the goal of accounting objects that can be reclaimed, but cannot be
allocated via a SLAB_RECLAIM_ACCOUNT cache.  This is now possible via
kmalloc() with __GFP_RECLAIMABLE flag, and the dcache external names user
is converted.

The counter is however still useful for accounting direct page allocations
(i.e.  not slab) with a shrinker, such as the ION page pool.  So keep it,
and:

- change granularity to pages to be more like other counters; sub-page
  allocations should be able to use kmalloc
- rename the counter to NR_KERNEL_MISC_RECLAIMABLE
- expose the counter again in vmstat as "nr_kernel_misc_reclaimable"; we can
  again remove the check for not printing "hidden" counters

Link: http://lkml.kernel.org/r/20180731090649.16028-5-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Christoph Lameter <cl@linux.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

(cherry picked from commit b29940c1abd7a4c3abeb926df0a5ec84d6902d47)

Conflicts:
        drivers/staging/android/ion/ion_page_pool.c

(1. NR_INDIRECTLY_RECLAIMABLE_BYTES accounting is absent, ignore it since
this patch replaces it anyway.)

Bug: 138148041
Test: verify KReclaimable accounting after ION allocation+deallocation
Change-Id: I6196eaa1e72f16dbde7a2894dc42435e75ae156c
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
2019-12-16 23:32:33 +00:00
Sami Tolvanen
ad751f33a5 FROMLIST: scs: add accounting
This change adds accounting for the memory allocated for shadow stacks.

Bug: 145210207
Change-Id: I51157fe0b23b4cb28bb33c86a5dfe3ac911296a4
(am from https://lore.kernel.org/patchwork/patch/1149055/)
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
2019-12-13 07:14:20 -08:00
Blagovest Kolenichev
070370f0ae Merge android-4.14.108 (4344de2) into msm-4.14
* refs/heads/tmp-4344de2:
  Linux 4.14.108
  s390/setup: fix boot crash for machine without EDAT-1
  KVM: nVMX: Ignore limit checks on VMX instructions using flat segments
  KVM: nVMX: Apply addr size mask to effective address for VMX instructions
  KVM: nVMX: Sign extend displacements of VMX instr's mem operands
  KVM: x86/mmu: Do not cache MMIO accesses while memslots are in flux
  KVM: x86/mmu: Detect MMIO generation wrap in any address space
  KVM: Call kvm_arch_memslots_updated() before updating memslots
  drm/radeon/evergreen_cs: fix missing break in switch statement
  media: imx: csi: Stop upstream before disabling IDMA channel
  media: imx: csi: Disable CSI immediately after last EOF
  media: vimc: Add vimc-streamer for stream control
  media: uvcvideo: Avoid NULL pointer dereference at the end of streaming
  media: imx: prpencvf: Stop upstream before disabling IDMA channel
  rcu: Do RCU GP kthread self-wakeup from softirq and interrupt
  tpm: Unify the send callback behaviour
  tpm/tpm_crb: Avoid unaligned reads in crb_recv()
  md: Fix failed allocation of md_register_thread
  perf intel-pt: Fix divide by zero when TSC is not available
  perf intel-pt: Fix overlap calculation for padding
  perf auxtrace: Define auxtrace record alignment
  perf intel-pt: Fix CYC timestamp calculation after OVF
  x86/unwind/orc: Fix ORC unwind table alignment
  bcache: never writeback a discard operation
  PM / wakeup: Rework wakeup source timer cancellation
  NFSv4.1: Reinitialise sequence results before retransmitting a request
  nfsd: fix wrong check in write_v4_end_grace()
  nfsd: fix memory corruption caused by readdir
  NFS: Don't recoalesce on error in nfs_pageio_complete_mirror()
  NFS: Fix an I/O request leakage in nfs_do_recoalesce
  NFS: Fix I/O request leakages
  cpcap-charger: generate events for userspace
  dm integrity: limit the rate of error messages
  dm: fix to_sector() for 32bit
  arm64: KVM: Fix architecturally invalid reset value for FPEXC32_EL2
  arm64: debug: Ensure debug handlers check triggering exception level
  arm64: Fix HCR.TGE status for NMI contexts
  ARM: s3c24xx: Fix boolean expressions in osiris_dvs_notify
  powerpc/traps: Fix the message printed when stack overflows
  powerpc/traps: fix recoverability of machine check handling on book3s/32
  powerpc/hugetlb: Don't do runtime allocation of 16G pages in LPAR configuration
  powerpc/ptrace: Simplify vr_get/set() to avoid GCC warning
  powerpc: Fix 32-bit KVM-PR lockup and host crash with MacOS guest
  powerpc/83xx: Also save/restore SPRG4-7 during suspend
  powerpc/powernv: Make opal log only readable by root
  powerpc/wii: properly disable use of BATs when requested.
  powerpc/32: Clear on-stack exception marker upon exception return
  security/selinux: fix SECURITY_LSM_NATIVE_LABELS on reused superblock
  jbd2: fix compile warning when using JBUFFER_TRACE
  jbd2: clear dirty flag when revoking a buffer from an older transaction
  serial: 8250_pci: Have ACCES cards that use the four port Pericom PI7C9X7954 chip use the pci_pericom_setup()
  serial: 8250_pci: Fix number of ports for ACCES serial cards
  serial: 8250_of: assume reg-shift of 2 for mrvl,mmp-uart
  serial: uartps: Fix stuck ISR if RX disabled with non-empty FIFO
  drm/i915: Relax mmap VMA check
  crypto: arm64/aes-neonbs - fix returning final keystream block
  i2c: tegra: fix maximum transfer size
  parport_pc: fix find_superio io compare code, should use equal test.
  intel_th: Don't reference unassigned outputs
  device property: Fix the length used in PROPERTY_ENTRY_STRING()
  kernel/sysctl.c: add missing range check in do_proc_dointvec_minmax_conv
  mm/vmalloc: fix size check for remap_vmalloc_range_partial()
  mm: hwpoison: fix thp split handing in soft_offline_in_use_page()
  nfit: acpi_nfit_ctl(): Check out_obj->type in the right place
  usb: chipidea: tegra: Fix missed ci_hdrc_remove_device()
  clk: ingenic: Fix doc of ingenic_cgu_div_info
  clk: ingenic: Fix round_rate misbehaving with non-integer dividers
  clk: clk-twl6040: Fix imprecise external abort for pdmclk
  clk: uniphier: Fix update register for CPU-gear
  ext2: Fix underflow in ext2_max_size()
  cxl: Wrap iterations over afu slices inside 'afu_list_lock'
  IB/hfi1: Close race condition on user context disable and close
  ext4: fix crash during online resizing
  ext4: add mask of ext4 flags to swap
  cpufreq: pxa2xx: remove incorrect __init annotation
  cpufreq: tegra124: add missing of_node_put()
  x86/kprobes: Prohibit probing on optprobe template code
  irqchip/gic-v3-its: Avoid parsing _indirect_ twice for Device table
  libertas_tf: don't set URB_ZERO_PACKET on IN USB transfer
  crypto: pcbc - remove bogus memcpy()s with src == dest
  Btrfs: fix corruption reading shared and compressed extents after hole punching
  btrfs: ensure that a DUP or RAID1 block group has exactly two stripes
  Btrfs: setup a nofs context for memory allocation at __btrfs_set_acl
  m68k: Add -ffreestanding to CFLAGS
  splice: don't merge into linked buffers
  fs/devpts: always delete dcache dentry-s in dput()
  scsi: target/iscsi: Avoid iscsit_release_commands_from_conn() deadlock
  scsi: sd: Optimal I/O size should be a multiple of physical block size
  scsi: aacraid: Fix performance issue on logical drives
  scsi: virtio_scsi: don't send sc payload with tmfs
  s390/virtio: handle find on invalid queue gracefully
  s390/setup: fix early warning messages
  clocksource/drivers/exynos_mct: Clear timer interrupt when shutdown
  clocksource/drivers/exynos_mct: Move one-shot check from tick clear to ISR
  regulator: s2mpa01: Fix step values for some LDOs
  regulator: max77620: Initialize values for DT properties
  regulator: s2mps11: Fix steps for buck7, buck8 and LDO35
  spi: pxa2xx: Setup maximum supported DMA transfer length
  spi: ti-qspi: Fix mmap read when more than one CS in use
  mmc: sdhci-esdhc-imx: fix HS400 timing issue
  ACPI / device_sysfs: Avoid OF modalias creation for removed device
  xen: fix dom0 boot on huge systems
  tracing: Do not free iter->trace in fail path of tracing_open_pipe()
  tracing: Use strncpy instead of memcpy for string keys in hist triggers
  CIFS: Fix read after write for files with read caching
  CIFS: Do not reset lease state to NONE on lease break
  crypto: arm64/aes-ccm - fix bugs in non-NEON fallback routine
  crypto: arm64/aes-ccm - fix logical bug in AAD MAC handling
  crypto: testmgr - skip crc32c context test for ahash algorithms
  crypto: hash - set CRYPTO_TFM_NEED_KEY if ->setkey() fails
  crypto: arm64/crct10dif - revert to C code for short inputs
  crypto: arm/crct10dif - revert to C code for short inputs
  fix cgroup_do_mount() handling of failure exits
  libnvdimm: Fix altmap reservation size calculation
  libnvdimm/pmem: Honor force_raw for legacy pmem regions
  libnvdimm, pfn: Fix over-trim in trim_pfn_device()
  libnvdimm/label: Clear 'updating' flag after label-set update
  stm class: Prevent division by zero
  media: videobuf2-v4l2: drop WARN_ON in vb2_warn_zero_bytesused()
  tmpfs: fix uninitialized return value in shmem_link
  net: set static variable an initial value in atl2_probe()
  nfp: bpf: fix ALU32 high bits clearance bug
  nfp: bpf: fix code-gen bug on BPF_ALU | BPF_XOR | BPF_K
  net: thunderx: make CFG_DONE message to run through generic send-ack sequence
  mac80211_hwsim: propagate genlmsg_reply return code
  phonet: fix building with clang
  ARCv2: support manual regfile save on interrupts
  ARC: uacces: remove lp_start, lp_end from clobber list
  ARCv2: lib: memcpy: fix doing prefetchw outside of buffer
  ixgbe: fix older devices that do not support IXGBE_MRQC_L3L4TXSWEN
  tmpfs: fix link accounting when a tmpfile is linked in
  net: marvell: mvneta: fix DMA debug warning
  arm64: Relax GIC version check during early boot
  qed: Fix iWARP syn packet mac address validation.
  ASoC: topology: free created components in tplg load error
  mailbox: bcm-flexrm-mailbox: Fix FlexRM ring flush timeout issue
  net: mv643xx_eth: disable clk on error path in mv643xx_eth_shared_probe()
  qmi_wwan: apply SET_DTR quirk to Sierra WP7607
  pinctrl: meson: meson8b: fix the sdxc_a data 1..3 pins
  net: systemport: Fix reception of BPDUs
  scsi: libiscsi: Fix race between iscsi_xmit_task and iscsi_complete_task
  keys: Fix dependency loop between construction record and auth key
  assoc_array: Fix shortcut creation
  af_key: unconditionally clone on broadcast
  ARM: 8824/1: fix a migrating irq bug when hotplug cpu
  esp: Skip TX bytes accounting when sending from a request socket
  clk: sunxi: A31: Fix wrong AHB gate number
  clk: sunxi-ng: v3s: Fix TCON reset de-assert bit
  Input: st-keyscan - fix potential zalloc NULL dereference
  auxdisplay: ht16k33: fix potential user-after-free on module unload
  i2c: bcm2835: Clear current buffer pointers and counts after a transfer
  i2c: cadence: Fix the hold bit setting
  net: hns: Fix object reference leaks in hns_dsaf_roce_reset()
  mm: page_alloc: fix ref bias in page_frag_alloc() for 1-byte allocs
  Revert "mm: use early_pfn_to_nid in page_ext_init"
  mm/gup: fix gup_pmd_range() for dax
  NFS: Don't use page_file_mapping after removing the page
  floppy: check_events callback should not return a negative number
  ipvs: fix dependency on nf_defrag_ipv6
  mac80211: Fix Tx aggregation session tear down with ITXQs
  Input: matrix_keypad - use flush_delayed_work()
  Input: ps2-gpio - flush TX work when closing port
  Input: cap11xx - switch to using set_brightness_blocking()
  ARM: OMAP2+: fix lack of timer interrupts on CPU1 after hotplug
  KVM: arm/arm64: Reset the VCPU without preemption and vcpu state loaded
  ASoC: rsnd: fixup rsnd_ssi_master_clk_start() user count check
  ASoC: dapm: fix out-of-bounds accesses to DAPM lookup tables
  ARM: OMAP2+: Variable "reg" in function omap4_dsi_mux_pads() could be uninitialized
  Input: pwm-vibra - stop regulator after disabling pwm, not before
  Input: pwm-vibra - prevent unbalanced regulator
  s390/dasd: fix using offset into zero size array error
  gpu: ipu-v3: Fix CSI offsets for imx53
  drm/imx: imx-ldb: add missing of_node_puts
  gpu: ipu-v3: Fix i.MX51 CSI control registers offset
  drm/imx: ignore plane updates on disabled crtcs
  crypto: rockchip - update new iv to device in multiple operations
  crypto: rockchip - fix scatterlist nents error
  crypto: ahash - fix another early termination in hash walk
  crypto: caam - fixed handling of sg list
  stm class: Fix an endless loop in channel allocation
  iio: adc: exynos-adc: Fix NULL pointer exception on unbind
  ASoC: fsl_esai: fix register setting issue in RIGHT_J mode
  9p/net: fix memory leak in p9_client_create
  9p: use inode->i_lock to protect i_size_write() under 32-bit
  FROMLIST: psi: introduce psi monitor
  FROMLIST: refactor header includes to allow kthread.h inclusion in psi_types.h
  FROMLIST: psi: track changed states
  FROMLIST: psi: split update_stats into parts
  FROMLIST: psi: rename psi fields in preparation for psi trigger addition
  FROMLIST: psi: make psi_enable static
  FROMLIST: psi: introduce state_mask to represent stalled psi states
  ANDROID: cuttlefish_defconfig: Enable CONFIG_INPUT_MOUSEDEV
  ANDROID: cuttlefish_defconfig: Enable CONFIG_PSI
  BACKPORT: kernel: cgroup: add poll file operation
  BACKPORT: fs: kernfs: add poll file operation
  UPSTREAM: psi: avoid divide-by-zero crash inside virtual machines
  UPSTREAM: psi: clarify the Kconfig text for the default-disable option
  UPSTREAM: psi: fix aggregation idle shut-off
  UPSTREAM: psi: fix reference to kernel commandline enable
  UPSTREAM: psi: make disabling/enabling easier for vendor kernels
  UPSTREAM: kernel/sched/psi.c: simplify cgroup_move_task()
  BACKPORT: psi: cgroup support
  UPSTREAM: psi: pressure stall information for CPU, memory, and IO
  UPSTREAM: sched: introduce this_rq_lock_irq()
  UPSTREAM: sched: sched.h: make rq locking and clock functions available in stats.h
  UPSTREAM: sched: loadavg: make calc_load_n() public
  BACKPORT: sched: loadavg: consolidate LOAD_INT, LOAD_FRAC, CALC_LOAD
  UPSTREAM: delayacct: track delays from thrashing cache pages
  UPSTREAM: mm: workingset: tell cache transitions from workingset thrashing
  sched/fair: fix energy compute when a cluster is only a cpu core in multi-cluster system

Conflicts:
	arch/arm/kernel/irq.c
	drivers/scsi/sd.c
	include/linux/sched.h
	include/uapi/linux/taskstats.h
	kernel/sched/Makefile
	sound/soc/soc-dapm.c

Change-Id: I12ebb57a34da9101ee19458d7e1f96ecc769c39a
Signed-off-by: Blagovest Kolenichev <bkolenichev@codeaurora.org>
2019-05-15 07:44:57 -07:00
Johannes Weiner
1d54f31271 UPSTREAM: mm: workingset: tell cache transitions from workingset thrashing
Refaults happen during transitions between workingsets as well as in-place
thrashing.  Knowing the difference between the two has a range of
applications, including measuring the impact of memory shortage on the
system performance, as well as the ability to smarter balance pressure
between the filesystem cache and the swap-backed workingset.

During workingset transitions, inactive cache refaults and pushes out
established active cache.  When that active cache isn't stale, however,
and also ends up refaulting, that's bonafide thrashing.

Introduce a new page flag that tells on eviction whether the page has been
active or not in its lifetime.  This bit is then stored in the shadow
entry, to classify refaults as transitioning or thrashing.

How many page->flags does this leave us with on 32-bit?

	20 bits are always page flags

	21 if you have an MMU

	23 with the zone bits for DMA, Normal, HighMem, Movable

	29 with the sparsemem section bits

	30 if PAE is enabled

	31 with this patch.

So on 32-bit PAE, that leaves 1 bit for distinguishing two NUMA nodes.  If
that's not enough, the system can switch to discontigmem and re-gain the 6
or 7 sparsemem section bits.

Link: http://lkml.kernel.org/r/20180828172258.3185-3-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Daniel Drake <drake@endlessm.com>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Johannes Weiner <jweiner@fb.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Enderborg <peter.enderborg@sony.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

(cherry picked from commit 8508cf3ffad4defa202b303e5b6379efc4cd9054)

Bug: 127712811
Test: lmkd in PSI mode
Change-Id: I71df060dce5590a3c654f9a0e8e54deeb74b64c2
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
2019-03-21 16:19:55 -07:00
Vijayanand Jitta
1f1ecb4423 mm: introduce NR_UNRECLAIMABLE_PAGES
Introduce NR_UNRECLAIMABLE_PAGES memory counter which accounts
the pages that cannot be reclaimed under memory pressure.

Change-Id: I9afe50537b0d3c2e7ffc07916b23cce4329e3679
Signed-off-by: Vijayanand Jitta <vjitta@codeaurora.org>
2019-03-19 22:50:10 -07:00
Roman Gushchin
c605894c84 mm: introduce NR_INDIRECTLY_RECLAIMABLE_BYTES
commit eb59254608bc1d42c4c6afdcdce9c0d3ce02b318 upstream.

Patch series "indirectly reclaimable memory", v2.

This patchset introduces the concept of indirectly reclaimable memory
and applies it to fix the issue of when a big number of dentries with
external names can significantly affect the MemAvailable value.

This patch (of 3):

Introduce a concept of indirectly reclaimable memory and adds the
corresponding memory counter and /proc/vmstat item.

Indirectly reclaimable memory is any sort of memory, used by the kernel
(except of reclaimable slabs), which is actually reclaimable, i.e.  will
be released under memory pressure.

The counter is in bytes, as it's not always possible to count such
objects in pages.  The name contains BYTES by analogy to
NR_KERNEL_STACK_KB.

Link: http://lkml.kernel.org/r/20180305133743.12746-2-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-18 09:16:25 +02:00
Liam Mark
b21c7a67e8 Revert "lowmemorykiller: fix cma accounting"
This reverts commit 263316a189 ("lowmemorykiller: fix cma accounting")
Re-introducing __GFP_CMA so revert this change and correct the logic to
simply check for MIGRATE_MOVABLE and __GFP_CMA.

Change-Id: Ifae86190f6db38de973c31958afac7ac7845ee73
Signed-off-by: Liam Mark <lmark@codeaurora.org>
2018-08-09 09:22:38 -07:00
Liam Mark
79360d60fe mm: add cma pcp list
Add a cma pcp list in order to increase cma memory utilization.

Increased cma memory utilization will improve overall memory
utilization because free cma pages are ignored when memory reclaim
is done with gfp mask GFP_KERNEL.

Since most memory reclaim is done by kswapd, which uses a gfp mask
of GFP_KERNEL, by increasing cma memory utilization we are therefore
ensuring that less aggressive memory reclaim takes place.

Increased cma memory utilization will improve performance,
for example it will increase app concurrency.

Change-Id: I809589a25c6abca51f1c963f118adfc78e955cf9
Signed-off-by: Liam Mark <lmark@codeaurora.org>
[vinmenon@codeaurora.org: fix !CONFIG_CMA compile time issues]
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
2018-08-06 09:49:48 -07:00
Heesub Shin
d29bd29a58 cma: redirect page allocation to CMA
CMA pages are designed to be used as fallback for movable allocations
and cannot be used for non-movable allocations. If CMA pages are
utilized poorly, non-movable allocations may end up getting starved if
all regular movable pages are allocated and the only pages left are
CMA. Always using CMA pages first creates unacceptable performance
problems. As a midway alternative, use CMA pages for certain
userspace allocations. The userspace pages can be migrated or dropped
quickly which giving decent utilization.

Change-Id: I6165dda01b705309eebabc6dfa67146b7a95c174
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Heesub Shin <heesub.shin@samsung.com
[lauraa@codeaurora.org: Missing CONFIG_CMA guards, add commit text]
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
[lmark@codeaurora.org: resolve conflicts relating to
 MIGRATE_HIGHATOMIC and some other trivial merge conflicts.]
Signed-off-by: Liam Mark <lmark@codeaurora.org>
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
2018-08-06 09:47:26 -07:00
Liam Mark
8df57cb4fa android/lowmemorykiller: Selectively count free CMA pages
In certain memory configurations there can be a large number of
CMA pages which are not suitable to satisfy certain memory
requests.

This large number of unsuitable pages can cause the
lowmemorykiller to not kill any tasks because the
lowmemorykiller counts all free pages.
In order to ensure the lowmemorykiller properly evaluates the
free memory only count the free CMA pages if they are suitable
for satisfying the memory request.

Change-Id: I7f06d53e2d8cfe7439e5561fe6e5209ce73b1c90
Signed-off-by: Liam Mark <lmark@codeaurora.org>
Signed-off-by: Vinayak Menon <vinmenon@codeaurora.org>
2018-07-03 18:24:32 -07:00
Roman Gushchin
fd82bbcb2b mm: introduce NR_INDIRECTLY_RECLAIMABLE_BYTES
Patch series "indirectly reclaimable memory", v2.

This patchset introduces the concept of indirectly reclaimable memory
and applies it to fix the issue of when a big number of dentries with
external names can significantly affect the MemAvailable value.

This patch (of 3):

Introduce a concept of indirectly reclaimable memory and adds the
corresponding memory counter and /proc/vmstat item.

Indirectly reclaimable memory is any sort of memory, used by the kernel
(except of reclaimable slabs), which is actually reclaimable, i.e.  will
be released under memory pressure.

The counter is in bytes, as it's not always possible to count such
objects in pages.  The name contains BYTES by analogy to
NR_KERNEL_STACK_KB.

Link: http://lkml.kernel.org/r/20180305133743.12746-2-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Git-Commit: eb59254608bc1d42c4c6afdcdce9c0d3ce02b318
Git-Repo: git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
Change-Id: I6ea0d449210973c92f57f3b7f5173e1ec85c81f8
Signed-off-by: Vijayanand Jitta <vjitta@codeaurora.org>
2018-05-13 20:01:21 +05:30
Kirill A. Shutemov
4afaf6ea65 mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y
commit 83e3c48729d9ebb7af5a31a504f3fd6aff0348c4 upstream.

Size of the mem_section[] array depends on the size of the physical address space.

In preparation for boot-time switching between paging modes on x86-64
we need to make the allocation of mem_section[] dynamic, because otherwise
we waste a lot of RAM: with CONFIG_NODE_SHIFT=10, mem_section[] size is 32kB
for 4-level paging and 2MB for 5-level paging mode.

The patch allocates the array on the first call to sparse_memory_present_with_active_regions().

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@suse.de>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170929140821.37654-2-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-25 14:26:15 +01:00
Pavel Tatashin
5a77c92fa1 mm/page_alloc.c: broken deferred calculation
commit d135e5750205a21a212a19dbb05aeb339e2cbea7 upstream.

In reset_deferred_meminit() we determine number of pages that must not
be deferred.  We initialize pages for at least 2G of memory, but also
pages for reserved memory in this node.

The reserved memory is determined in this function:
memblock_reserved_memory_within(), which operates over physical
addresses, and returns size in bytes.  However, reset_deferred_meminit()
assumes that that this function operates with pfns, and returns page
count.

The result is that in the best case machine boots slower than expected
due to initializing more pages than needed in single thread, and in the
worst case panics because fewer than needed pages are initialized early.

Link: http://lkml.kernel.org/r/20171021011707.15191-1-pasha.tatashin@oracle.com
Fixes: 864b9a393d ("mm: consider memblock reservations for deferred memory initialization sizing")
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-24 08:37:05 +01:00
Greg Kroah-Hartman
b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
YASUAKI ISHIMATSU
1dd2bfc868 mm/memory_hotplug: change pfn_to_section_nr/section_nr_to_pfn macro to inline function
pfn_to_section_nr() and section_nr_to_pfn() are defined as macro.
pfn_to_section_nr() has no issue even if it is defined as macro.  But
section_nr_to_pfn() has overflow issue if sec is defined as int.

section_nr_to_pfn() just shifts sec by PFN_SECTION_SHIFT.  If sec is
defined as unsigned long, section_nr_to_pfn() returns pfn as 64 bit value.
But if sec is defined as int, section_nr_to_pfn() returns pfn as 32 bit
value.

__remove_section() calculates start_pfn using section_nr_to_pfn() and
scn_nr defined as int.  So if hot-removed memory address is over 16TB,
overflow issue occurs and section_nr_to_pfn() does not calculate correct
pfn.

To make callers use proper arg, the patch changes the macros to inline
functions.

Fixes: 815121d2b5 ("memory_hotplug: clear zone when removing the memory")
Link: http://lkml.kernel.org/r/e643a387-e573-6bbf-d418-c60c8ee3d15e@gmail.com
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Xishi Qiu <qiuxishi@huawei.com>
Cc: Reza Arbab <arbab@linux.vnet.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03 17:54:25 -07:00
Kemi Wang
1d90ca897c mm: update NUMA counter threshold size
There is significant overhead in cache bouncing caused by zone counters
(NUMA associated counters) update in parallel in multi-threaded page
allocation (suggested by Dave Hansen).

This patch updates NUMA counter threshold to a fixed size of MAX_U16 - 2,
as a small threshold greatly increases the update frequency of the global
counter from local per cpu counter(suggested by Ying Huang).

The rationality is that these statistics counters don't affect the
kernel's decision, unlike other VM counters, so it's not a problem to use
a large threshold.

With this patchset, we see 31.3% drop of CPU cycles(537-->369) for per
single page allocation and reclaim on Jesper's page_bench03 benchmark.

Benchmark provided by Jesper D Brouer(increase loop times to 10000000):
https://github.com/netoptimizer/prototype-kernel/tree/master/kernel/mm/
bench

 Threshold   CPU cycles    Throughput(88 threads)
     32          799         241760478
     64          640         301628829
     125         537         358906028 <==> system by default (base)
     256         468         412397590
     512         428         450550704
     4096        399         482520943
     20000       394         489009617
     30000       395         488017817
     65533       369(-31.3%) 521661345(+45.3%) <==> with this patchset
     N/A         342(-36.3%) 562900157(+56.8%) <==> disable zone_statistics

Link: http://lkml.kernel.org/r/1503568801-21305-3-git-send-email-kemi.wang@intel.com
Signed-off-by: Kemi Wang <kemi.wang@intel.com>
Reported-by: Jesper Dangaard Brouer <brouer@redhat.com>
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Suggested-by: Ying Huang <ying.huang@intel.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 18:26:47 -07:00
Kemi Wang
3a321d2a3d mm: change the call sites of numa statistics items
Patch series "Separate NUMA statistics from zone statistics", v2.

Each page allocation updates a set of per-zone statistics with a call to
zone_statistics().  As discussed in 2017 MM summit, these are a
substantial source of overhead in the page allocator and are very rarely
consumed.  This significant overhead in cache bouncing caused by zone
counters (NUMA associated counters) update in parallel in multi-threaded
page allocation (pointed out by Dave Hansen).

A link to the MM summit slides:
  http://people.netfilter.org/hawk/presentations/MM-summit2017/MM-summit2017-JesperBrouer.pdf

To mitigate this overhead, this patchset separates NUMA statistics from
zone statistics framework, and update NUMA counter threshold to a fixed
size of MAX_U16 - 2, as a small threshold greatly increases the update
frequency of the global counter from local per cpu counter (suggested by
Ying Huang).  The rationality is that these statistics counters don't
need to be read often, unlike other VM counters, so it's not a problem
to use a large threshold and make readers more expensive.

With this patchset, we see 31.3% drop of CPU cycles(537-->369, see
below) for per single page allocation and reclaim on Jesper's
page_bench03 benchmark.  Meanwhile, this patchset keeps the same style
of virtual memory statistics with little end-user-visible effects (only
move the numa stats to show behind zone page stats, see the first patch
for details).

I did an experiment of single page allocation and reclaim concurrently
using Jesper's page_bench03 benchmark on a 2-Socket Broadwell-based
server (88 processors with 126G memory) with different size of threshold
of pcp counter.

Benchmark provided by Jesper D Brouer(increase loop times to 10000000):
  https://github.com/netoptimizer/prototype-kernel/tree/master/kernel/mm/bench

   Threshold   CPU cycles    Throughput(88 threads)
      32        799         241760478
      64        640         301628829
      125       537         358906028 <==> system by default
      256       468         412397590
      512       428         450550704
      4096      399         482520943
      20000     394         489009617
      30000     395         488017817
      65533     369(-31.3%) 521661345(+45.3%) <==> with this patchset
      N/A       342(-36.3%) 562900157(+56.8%) <==> disable zone_statistics

This patch (of 3):

In this patch, NUMA statistics is separated from zone statistics
framework, all the call sites of NUMA stats are changed to use
numa-stats-specific functions, it does not have any functionality change
except that the number of NUMA stats is shown behind zone page stats
when users *read* the zone info.

E.g. cat /proc/zoneinfo
    ***Base***                           ***With this patch***
nr_free_pages 3976                         nr_free_pages 3976
nr_zone_inactive_anon 0                    nr_zone_inactive_anon 0
nr_zone_active_anon 0                      nr_zone_active_anon 0
nr_zone_inactive_file 0                    nr_zone_inactive_file 0
nr_zone_active_file 0                      nr_zone_active_file 0
nr_zone_unevictable 0                      nr_zone_unevictable 0
nr_zone_write_pending 0                    nr_zone_write_pending 0
nr_mlock     0                             nr_mlock     0
nr_page_table_pages 0                      nr_page_table_pages 0
nr_kernel_stack 0                          nr_kernel_stack 0
nr_bounce    0                             nr_bounce    0
nr_zspages   0                             nr_zspages   0
numa_hit 0                                *nr_free_cma  0*
numa_miss 0                                numa_hit     0
numa_foreign 0                             numa_miss    0
numa_interleave 0                          numa_foreign 0
numa_local   0                             numa_interleave 0
numa_other   0                             numa_local   0
*nr_free_cma 0*                            numa_other 0
    ...                                        ...
vm stats threshold: 10                     vm stats threshold: 10
    ...                                        ...

The next patch updates the numa stats counter size and threshold.

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/1503568801-21305-2-git-send-email-kemi.wang@intel.com
Signed-off-by: Kemi Wang <kemi.wang@intel.com>
Reported-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Ying Huang <ying.huang@intel.com>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-08 18:26:47 -07:00
Michal Hocko
b93e0f329e mm, memory_hotplug: get rid of zonelists_mutex
zonelists_mutex was introduced by commit 4eaf3f6439 ("mem-hotplug: fix
potential race while building zonelist for new populated zone") to
protect zonelist building from races.  This is no longer needed though
because both memory online and offline are fully serialized.  New users
have grown since then.

Notably setup_per_zone_wmarks wants to prevent from races between memory
hotplug, khugepaged setup and manual min_free_kbytes update via sysctl
(see cfd3da1e49 ("mm: Serialize access to min_free_kbytes").  Let's
add a private lock for that purpose.  This will not prevent from seeing
halfway through memory hotplug operation but that shouldn't be a big
deal becuse memory hotplug will update watermarks explicitly so we will
eventually get a full picture.  The lock just makes sure we won't race
when updating watermarks leading to weird results.

Also __build_all_zonelists manipulates global data so add a private lock
for it as well.  This doesn't seem to be necessary today but it is more
robust to have a lock there.

While we are at it make sure we document that memory online/offline
depends on a full serialization either via mem_hotplug_begin() or
device_lock.

Link: http://lkml.kernel.org/r/20170721143915.14161-9-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Haicheng Li <haicheng.li@linux.intel.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:26 -07:00
Michal Hocko
72675e131e mm, memory_hotplug: drop zone from build_all_zonelists
build_all_zonelists gets a zone parameter to initialize zone's pagesets.
There is only a single user which gives a non-NULL zone parameter and
that one doesn't really need the rest of the build_all_zonelists (see
commit 6dcd73d701 ("memory-hotplug: allocate zone's pcp before
onlining pages")).

Therefore remove setup_zone_pageset from build_all_zonelists and call it
from its only user directly.  This will also remove a pointless zonlists
rebuilding which is always good.

Link: http://lkml.kernel.org/r/20170721143915.14161-5-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:25 -07:00
Michal Hocko
c9bff3eebc mm, page_alloc: rip out ZONELIST_ORDER_ZONE
Patch series "cleanup zonelists initialization", v1.

This is aimed at cleaning up the zonelists initialization code we have
but the primary motivation was bug report [2] which got resolved but the
usage of stop_machine is just too ugly to live.  Most patches are
straightforward but 3 of them need a special consideration.

Patch 1 removes zone ordered zonelists completely.  I am CCing linux-api
because this is a user visible change.  As I argue in the patch
description I do not think we have a strong usecase for it these days.
I have kept sysctl in place and warn into the log if somebody tries to
configure zone lists ordering.  If somebody has a real usecase for it we
can revert this patch but I do not expect anybody will actually notice
runtime differences.  This patch is not strictly needed for the rest but
it made patch 6 easier to implement.

Patch 7 removes stop_machine from build_all_zonelists without adding any
special synchronization between iterators and updater which I _believe_
is acceptable as explained in the changelog.  I hope I am not missing
anything.

Patch 8 then removes zonelists_mutex which is kind of ugly as well and
not really needed AFAICS but a care should be taken when double checking
my thinking.

This patch (of 9):

Supporting zone ordered zonelists costs us just a lot of code while the
usefulness is arguable if existent at all.  Mel has already made node
ordering default on 64b systems.  32b systems are still using
ZONELIST_ORDER_ZONE because it is considered better to fallback to a
different NUMA node rather than consume precious lowmem zones.

This argument is, however, weaken by the fact that the memory reclaim
has been reworked to be node rather than zone oriented.  This means that
lowmem requests have to skip over all highmem pages on LRUs already and
so zone ordering doesn't save the reclaim time much.  So the only
advantage of the zone ordering is under a light memory pressure when
highmem requests do not ever hit into lowmem zones and the lowmem
pressure doesn't need to reclaim.

Considering that 32b NUMA systems are rather suboptimal already and it
is generally advisable to use 64b kernel on such a HW I believe we
should rather care about the code maintainability and just get rid of
ZONELIST_ORDER_ZONE altogether.  Keep systcl in place and warn if
somebody tries to set zone ordering either from kernel command line or
the sysctl.

[mhocko@suse.com: reading vm.numa_zonelist_order will never terminate]
Link: http://lkml.kernel.org/r/20170721143915.14161-2-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Shaohua Li <shaohua.li@intel.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Cc: <linux-api@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-06 17:27:25 -07:00