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android / kernel / common / 3e591c63b13772a1de0ffed995b482166d27ed71
commit3e591c63b13772a1de0ffed995b482166d27ed71[log] [tgz]
authorMartin Liu <liumartin@google.com>Wed Apr 20 16:47:57 2022 +0800
committerMartin Liu <liumartin@google.com>Wed Apr 27 03:05:53 2022 +0000
tree27d6b42c028813f4cae89c1cf4fa5822ca418889
parentc56ecad17200341be24bc07af6cf3623bba4f83b [diff]
ANDROID: cma: allow to use CMA in swap-in path

Now, we allow to use CMA pages for certain user space
allocations. One of them is anonymous page fault case.
To align the use case, we should also allow to use CMA
pages in swap-in cases. This could help mitigate OOM
on swap-in cases showing plenty of free CMA left.

logd.klogd invoked oom-killer: gfp_mask=0x1100cca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=-1000
CPU: 0 PID: 433 Comm: logd.klogd Tainted: G        W  OE     5.10.100-android13-0 #1

Call trace:
 dump_backtrace.cfi_jt+0x0/0x8
 show_stack+0x1c/0x2c
 dump_stack_lvl+0xc0/0x13c
 dump_header+0x54/0x238
 oom_kill_process+0xb0/0x158
 out_of_memory+0x17c/0x328
 __alloc_pages_slowpath+0x5c4/0x8d0
 __alloc_pages_nodemask+0x1bc/0x2e0
 __read_swap_cache_async+0xdc/0x370
 swap_vma_readahead+0x3b4/0x488
 swapin_readahead+0x3c/0x54
 do_swap_page+0x1e0/0xaa0
 handle_pte_fault+0x128/0x1e0
 handle_mm_fault+0x308/0x590
 do_page_fault+0x33c/0x478
 do_translation_fault+0x58/0x11c
 do_mem_abort+0x68/0x144
 el0_da+0x24/0x34
 el0_sync_handler+0xc4/0xec
 el0_sync+0x1c0/0x200
Mem-Info:
active_anon:0 inactive_anon:3222 isolated_anon:62
 active_file:232 inactive_file:428 isolated_file:0
 unevictable:37232 dirty:3 writeback:40
 slab_reclaimable:19943 slab_unreclaimable:281193
 mapped:37126 shmem:2815 pagetables:8981 bounce:0
 free:126007 free_pcp:223 free_cma:123062
Node 0 active_anon:16kB inactive_anon:13160kB active_file:292kB inactive_file:2000kB unevictable:148928kB isolated(anon):0kB isolated(file):0kB mapped:148308kB dirty:12kB writeback:164kB shmem:11260kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 0kB writeback_tmp:0kB kernel_stack:20528kB shadow_call_stack:5200kB all_unreclaimable? no
DMA32 free:14128kB min:7572kB low:22636kB high:37700kB reserved_highatomic:4096KB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:1913856kB managed:1553276kB mlocked:0kB pagetables:1292kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:2520kB
lowmem_reserve[]: 0 0 0
Normal free:489888kB min:19808kB low:59220kB high:98632kB reserved_highatomic:36864KB active_anon:20kB inactive_anon:12168kB active_file:0kB inactive_file:1640kB unevictable:148928kB writepending:180kB present:4194304kB managed:4063392kB mlocked:148928kB pagetables:34632kB bounce:0kB free_pcp:1928kB local_pcp:0kB free_cma:489752kB
lowmem_reserve[]: 0 0 0
DMA32: 166*4kB (UME) 163*8kB (UMECH) 592*16kB (UMCH) 5*32kB (UC) 2*64kB (C) 2*128kB (C) 2*256kB (C) 1*512kB (C) 1*1024kB (C) 0*2048kB 0*4096kB = 14032kB
Normal: 969*4kB (C) 77*8kB (C) 40*16kB (C) 17*32kB (C) 5*64kB (C) 1*128kB (C) 2*256kB (C) 1*512kB (C) 0*1024kB 0*2048kB 118*4096kB (C) = 490476kB
40220 total pagecache pages
30 pages in swap cache
Swap cache stats: add 2634625, delete 2635304, find 160621/2963954
Free swap  = 1473788kB
Total swap = 2097148kB

Bug: 229822798
Signed-off-by: Martin Liu <liumartin@google.com>
Change-Id: Ia0bb6f72e52f77f26062e1769bfd92e831f07cab
1 file changed
tree: 27d6b42c028813f4cae89c1cf4fa5822ca418889
  1. android/
  2. arch/
  3. block/
  4. certs/
  5. crypto/
  6. Documentation/
  7. drivers/
  8. fs/
  9. include/
  10. init/
  11. ipc/
  12. kernel/
  13. lib/
  14. LICENSES/
  15. mm/
  16. net/
  17. samples/
  18. scripts/
  19. security/
  20. sound/
  21. tools/
  22. usr/
  23. virt/
  24. .clang-format
  25. .cocciconfig
  26. .get_maintainer.ignore
  27. .gitattributes
  28. .gitignore
  29. .mailmap
  30. BUILD.bazel
  31. build.config.aarch64
  32. build.config.allmodconfig
  33. build.config.allmodconfig.aarch64
  34. build.config.allmodconfig.arm
  35. build.config.allmodconfig.x86_64
  36. build.config.amlogic
  37. build.config.arm
  38. build.config.common
  39. build.config.constants
  40. build.config.db845c
  41. build.config.gki
  42. build.config.gki-debug.aarch64
  43. build.config.gki-debug.x86_64
  44. build.config.gki.aarch64
  45. build.config.gki.aarch64.fips140
  46. build.config.gki.x86_64
  47. build.config.gki_kasan
  48. build.config.gki_kasan.aarch64
  49. build.config.gki_kasan.x86_64
  50. build.config.gki_kprobes
  51. build.config.gki_kprobes.aarch64
  52. build.config.gki_kprobes.x86_64
  53. build.config.hikey960
  54. build.config.khwasan
  55. build.config.rockpi4
  56. build.config.x86_64
  57. COPYING
  58. CREDITS
  59. Kbuild
  60. Kconfig
  61. MAINTAINERS
  62. Makefile
  63. OWNERS
  64. README
  65. README.md
README.md

How do I submit patches to Android Common Kernels

  1. BEST: Make all of your changes to upstream Linux. If appropriate, backport to the stable releases. These patches will be merged automatically in the corresponding common kernels. If the patch is already in upstream Linux, post a backport of the patch that conforms to the patch requirements below.

    • Do not send patches upstream that contain only symbol exports. To be considered for upstream Linux, additions of EXPORT_SYMBOL_GPL() require an in-tree modular driver that uses the symbol -- so include the new driver or changes to an existing driver in the same patchset as the export.
    • When sending patches upstream, the commit message must contain a clear case for why the patch is needed and beneficial to the community. Enabling out-of-tree drivers or functionality is not not a persuasive case.

  2. LESS GOOD: Develop your patches out-of-tree (from an upstream Linux point-of-view). Unless these are fixing an Android-specific bug, these are very unlikely to be accepted unless they have been coordinated with kernel-team@android.com. If you want to proceed, post a patch that conforms to the patch requirements below.

Common Kernel patch requirements

  • All patches must conform to the Linux kernel coding standards and pass script/checkpatch.pl
  • Patches shall not break gki_defconfig or allmodconfig builds for arm, arm64, x86, x86_64 architectures (see https://source.android.com/setup/build/building-kernels)
  • If the patch is not merged from an upstream branch, the subject must be tagged with the type of patch: UPSTREAM:, BACKPORT:, FROMGIT:, FROMLIST:, or ANDROID:.
  • All patches must have a Change-Id: tag (see https://gerrit-review.googlesource.com/Documentation/user-changeid.html)
  • If an Android bug has been assigned, there must be a Bug: tag.
  • All patches must have a Signed-off-by: tag by the author and the submitter

Additional requirements are listed below based on patch type

Requirements for backports from mainline Linux: UPSTREAM:, BACKPORT:

  • If the patch is a cherry-pick from Linux mainline with no changes at all
    • tag the patch subject with UPSTREAM:.
    • add upstream commit information with a (cherry picked from commit ...) line
    • Example:
      • if the upstream commit message is
        important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>
  • then Joe Smith would upload the patch for the common kernel as
        UPSTREAM: important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>

        Bug: 135791357
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        (cherry picked from commit c31e73121f4c1ec41143423ac6ce3ce6dafdcec1)
        Signed-off-by: Joe Smith <joe.smith@foo.org>
  • If the patch requires any changes from the upstream version, tag the patch with BACKPORT: instead of UPSTREAM:.
    • use the same tags as UPSTREAM:
    • add comments about the changes under the (cherry picked from commit ...) line
    • Example:
        BACKPORT: important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>

        Bug: 135791357
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        (cherry picked from commit c31e73121f4c1ec41143423ac6ce3ce6dafdcec1)
        [joe: Resolved minor conflict in drivers/foo/bar.c ]
        Signed-off-by: Joe Smith <joe.smith@foo.org>

Requirements for other backports: FROMGIT:, FROMLIST:,

  • If the patch has been merged into an upstream maintainer tree, but has not yet been merged into Linux mainline
    • tag the patch subject with FROMGIT:
    • add info on where the patch came from as (cherry picked from commit <sha1> <repo> <branch>). This must be a stable maintainer branch (not rebased, so don't use linux-next for example).
    • if changes were required, use BACKPORT: FROMGIT:
    • Example:
      • if the commit message in the maintainer tree is
        important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>
  • then Joe Smith would upload the patch for the common kernel as
        FROMGIT: important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>

        Bug: 135791357
        (cherry picked from commit 878a2fd9de10b03d11d2f622250285c7e63deace
         https://git.kernel.org/pub/scm/linux/kernel/git/foo/bar.git test-branch)
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        Signed-off-by: Joe Smith <joe.smith@foo.org>
  • If the patch has been submitted to LKML, but not accepted into any maintainer tree
    • tag the patch subject with FROMLIST:
    • add a Link: tag with a link to the submittal on lore.kernel.org
    • add a Bug: tag with the Android bug (required for patches not accepted into a maintainer tree)
    • if changes were required, use BACKPORT: FROMLIST:
    • Example:
        FROMLIST: important patch from upstream

        This is the detailed description of the important patch

        Signed-off-by: Fred Jones <fred.jones@foo.org>

        Bug: 135791357
        Link: https://lore.kernel.org/lkml/20190619171517.GA17557@someone.com/
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        Signed-off-by: Joe Smith <joe.smith@foo.org>

Requirements for Android-specific patches: ANDROID:

  • If the patch is fixing a bug to Android-specific code
    • tag the patch subject with ANDROID:
    • add a Fixes: tag that cites the patch with the bug
    • Example:
        ANDROID: fix android-specific bug in foobar.c

        This is the detailed description of the important fix

        Fixes: 1234abcd2468 ("foobar: add cool feature")
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        Signed-off-by: Joe Smith <joe.smith@foo.org>
  • If the patch is a new feature
    • tag the patch subject with ANDROID:
    • add a Bug: tag with the Android bug (required for android-specific features)