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android / kernel / common / 1c8aebe4c072bf18409cc78fc84407e24a437302
commit1c8aebe4c072bf18409cc78fc84407e24a437302[log] [tgz]
authorHeesub Shin <[email protected]>Mon Feb 12 12:39:40 2024 -0800
committerCarlos Llamas <[email protected]>Fri Apr 26 03:46:17 2024 +0000
tree5115e721011cdb94e21e04eca481cde0c65bc1b7
parent9ea0eb4f48031efa9040aab65fb2ad70b1f301ee [diff]
ANDROID: 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.

Additionally, add a fall-backs for failed CMA allocations in rmqueue()
and __rmqueue_pcplist() (the latter addition being driven by a report
by the kernel test robot); these fallbacks were dealt with differently
in the original version of the patch as the rmqueue() call chain has
changed).

[ACK6.6 port notes]
    Add a command line option, 'restrict_cma_fallback` and redirect page
    allocation to CMA only if this option is specified.  If the option is
    not specified, there should be no change in behavior. When the option
    is specified, only allocations tagged with __GFP_CMA are redirected
    (as in ACK 6.1). We considered adding a vendor hook, but couldn't
    find a good place for the hook. We only need to initialize the flag
    once - unlike normal vendor hooks which operate on other variables
    in the context of the hook. But the vendor hook can't be too early
    in the boot since the trace infrastructure is not yet initialized.

Bug: 330201547
Change-Id: Iad46f0405b416e29ae788f82b79c9953513a9c9d
Link: https://lore.kernel.org/lkml/[email protected]/
Reported-by: kernel test robot <[email protected]>
Signed-off-by: Kyungmin Park <[email protected]>
Signed-off-by: Heesub Shin <[email protected]>
Signed-off-by: Vinayak Menon <[email protected]>
[[email protected]: Place in bugfixes; remove cma_alloc zone flag]
Signed-off-by: Chris Goldsworthy <[email protected]>
[[email protected]: Resolve merge conflicts to account for new mm
features]
Signed-off-by: Isaac J. Manjarres <[email protected]>
[Port to ACK6.6 with input from Chris Goldsworthy and Patrick Daly]
Signed-off-by: Sukadev Bhattiprolu <[email protected]>
6 files changed
tree: 5115e721011cdb94e21e04eca481cde0c65bc1b7
  1. android/
  2. arch/
  3. block/
  4. certs/
  5. crypto/
  6. Documentation/
  7. drivers/
  8. fs/
  9. include/
  10. init/
  11. io_uring/
  12. ipc/
  13. kernel/
  14. lib/
  15. LICENSES/
  16. mm/
  17. net/
  18. rust/
  19. samples/
  20. scripts/
  21. security/
  22. sound/
  23. tools/
  24. usr/
  25. virt/
  26. .clang-format
  27. .cocciconfig
  28. .get_maintainer.ignore
  29. .gitattributes
  30. .gitignore
  31. .mailmap
  32. .rustfmt.toml
  33. abi.bzl
  34. BUILD.bazel
  35. build.config.aarch64
  36. build.config.allmodconfig
  37. build.config.allmodconfig.aarch64
  38. build.config.allmodconfig.arm
  39. build.config.allmodconfig.x86_64
  40. build.config.amlogic
  41. build.config.arm
  42. build.config.common
  43. build.config.constants
  44. build.config.crashdump
  45. build.config.crashdump.aarch64
  46. build.config.crashdump.x86_64
  47. build.config.db845c
  48. build.config.gki
  49. build.config.gki.aarch64
  50. build.config.gki.riscv64
  51. build.config.gki.x86_64
  52. build.config.gki_kasan
  53. build.config.gki_kasan.aarch64
  54. build.config.gki_kasan.x86_64
  55. build.config.gki_kprobes
  56. build.config.gki_kprobes.aarch64
  57. build.config.gki_kprobes.x86_64
  58. build.config.khwasan
  59. build.config.kunit.aarch64
  60. build.config.kunit.riscv64
  61. build.config.kunit.x86_64
  62. build.config.microdroid
  63. build.config.microdroid.aarch64
  64. build.config.microdroid.x86_64
  65. build.config.riscv64
  66. build.config.rockpi4
  67. build.config.x86_64
  68. COPYING
  69. CREDITS
  70. Kbuild
  71. Kconfig
  72. Kconfig.ext
  73. MAINTAINERS
  74. Makefile
  75. modules.bzl
  76. OWNERS
  77. README
  78. 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 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 [email protected]. 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 scripts/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 <[email protected]>
  • 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 <[email protected]>

        Bug: 135791357
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        (cherry picked from commit c31e73121f4c1ec41143423ac6ce3ce6dafdcec1)
        Signed-off-by: Joe Smith <[email protected]>
  • 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 <[email protected]>

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

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 <[email protected]>
  • 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 <[email protected]>

        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 <[email protected]>
  • 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 <[email protected]>

        Bug: 135791357
        Link: https://lore.kernel.org/lkml/[email protected]/
        Change-Id: I4caaaa566ea080fa148c5e768bb1a0b6f7201c01
        Signed-off-by: Joe Smith <[email protected]>

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 <[email protected]>
  • 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)