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review.shift-gmbh.com / SHIFTPHONES / kernel / shift / mainline / d8b946254effbe36780f0b855da509a07470b8d2
commitd8b946254effbe36780f0b855da509a07470b8d2[log] [tgz]
authorBart Van Assche <bvanassche@acm.org>Tue Aug 03 09:15:12 2021 -0700
committerBart Van Assche <bvanassche@google.com>Thu Aug 05 12:21:53 2021 -0700
treebda10a2b096fcf8f0ace84d1984e3983a19cfdc8
parent8914725a582861666a2a298efbcb5ae7613a47b7 [diff]
FROMGIT: blk-mq: Introduce the BLK_MQ_F_NO_SCHED_BY_DEFAULT flag

elevator_get_default() uses the following algorithm to select an I/O
scheduler from inside add_disk():
- In case of a single hardware queue or sharing hardware queues across
  multiple request queues (BLK_MQ_F_TAG_HCTX_SHARED), use mq-deadline.
- Otherwise, use 'none'.

This is a good choice for most but not for all block drivers. Make it
possible to override the selection of mq-deadline with a new flag,
namely BLK_MQ_F_NO_SCHED_BY_DEFAULT.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Bug: 194450129
(cherry picked from commit 90b7198001f23ea37d3b46dc631bdaa2357a20b1 git://git.kernel.dk/linux-block/ for-5.15/block)
Change-Id: I4fb658957c193f350e74bdb5876c20a8f628fcb1
Signed-off-by: Bart Van Assche <bvanassche@google.com>
2 files changed
tree: bda10a2b096fcf8f0ace84d1984e3983a19cfdc8
  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.config.aarch64
  31. build.config.allmodconfig
  32. build.config.allmodconfig.aarch64
  33. build.config.allmodconfig.arm
  34. build.config.allmodconfig.x86_64
  35. build.config.amlogic
  36. build.config.arm
  37. build.config.common
  38. build.config.db845c
  39. build.config.gki
  40. build.config.gki-debug.aarch64
  41. build.config.gki-debug.x86_64
  42. build.config.gki.aarch64
  43. build.config.gki.aarch64.fips140
  44. build.config.gki.x86_64
  45. build.config.gki_kasan
  46. build.config.gki_kasan.aarch64
  47. build.config.gki_kasan.x86_64
  48. build.config.gki_kprobes
  49. build.config.gki_kprobes.aarch64
  50. build.config.gki_kprobes.x86_64
  51. build.config.hikey960
  52. build.config.khwasan
  53. build.config.x86_64
  54. COPYING
  55. CREDITS
  56. Kbuild
  57. Kconfig
  58. MAINTAINERS
  59. Makefile
  60. OWNERS
  61. README
  62. 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)