[PATCH v6 00/14] Enable lock context analysis for the block layer core

[Bart Van Assche <bvanassche@acm.org>]

Hi Jens,

Recently the following patch series has been merged: [PATCH v5 00/36]
Compiler-Based Context- and Locking-Analysis
(https://lore.kernel.org/lkml/20251219154418.3592607-1-elver@google.com/). That
patch series drops support for verifying lock context annotations with sparse
and introduces support for verifying lock context annotations with Clang. The
support in Clang for lock context annotation and verification is better than
that in sparse. As an example, __cond_acquires() and __guarded_by() are
supported by Clang but not by sparse. Hence this patch series that enables lock
context analysis for the block layer core.

Note: although the Linux kernel documentation specifies 22 as minimal
version for Clang for context analysis support, this patch series requires
Clang 23 because it annotates function pointers. As one can see here, a patch
has been queued that fixes the kernel documentation:
https://lore.kernel.org/all/177926568868.711.3058599932884307249.tip-bot2@tip-bot2/

Please consider this patch series for the next merge window.

Thanks,

Bart.

Changes compared to v5:
 - Made the description of patch "block/cgroup: Inline
   blkg_conf_{open,close}_bdev_frozen()" more clear.
 - Combined two error paths in ioc_qos_write().
 - Folded iocg_lock() and iocg_unlock() into their callers. Removed the token
   context lock "ioc_lock".
 - Introduced macros in the debugfs code that capture expressions with
   pointer casts.
 - Added two patches: "block/blk-iocost: Combine two error paths in
   ioc_qos_write()" and "block/blk-iocost: Split ioc_rqos_throttle()".

Changes compared to v4:
 - Rebased and retested on top of Jens' latest for-next branch.

Changes compared to v3:
 - Replaced the "block/bdev: Annotate the blk_holder_ops callback invocations"
   patch with a patch that adds __releases() annotations to the function
   pointers in struct blk_holder_ops.
 - Dropped the blk-zoned patch since a better patch from Christoph has
   been merged.

Changes compared to v2:
 - Retained the block layer core patches and left out the block driver patches.
 - Inlined blkg_conf_open_bdev_frozen() and blkg_conf_close_bdev_frozen().
 - In blkg_conf_open_bdev(), added a return statement if the
   WARN_ON_ONCE() statement triggers.
 - Replaced the "block/ioctl: Add lock context annotations" patch with a
   __release() annotation.
 - Replaced the blk-zoned patch with a patch from Christoph.

Changes compared to v1:
 - Rebased this patch series on top of Jens' for-next branch.
 - Included two patches that split blkg_conf_prep() and blkg_conf_exit().
 - Modified how patches are split. Split the block layer core patch into
   multiple patches and moved the CONTEXT_ANALYSIS := y assignments into the
   block driver patches.
 - Made the new source code comments easier to comprehend.
 - Introduced macros in the mq-deadline and Kyber I/O schedulers to make the
   __acquires() expressions easier to read.
 - Removed the changes from this series that are not block layer changes.

Bart Van Assche (14):
  block: Annotate the queue limits functions
  block/bdev: Annotate the blk_holder_ops callback functions
  block/cgroup: Split blkg_conf_prep()
  block/cgroup: Split blkg_conf_exit()
  block/cgroup: Improve lock context annotations
  block/blk-iocost: Combine two error paths in ioc_qos_write()
  block/cgroup: Inline blkg_conf_{open,close}_bdev_frozen()
  block/crypto: Annotate the crypto functions
  block/blk-iocost: Split ioc_rqos_throttle()
  block/blk-iocost: Inline iocg_lock() and iocg_unlock()
  block/blk-mq-debugfs: Improve lock context annotations
  block/Kyber: Make the lock context annotations compatible with Clang
  block/mq-deadline: Make the lock context annotations compatible with
    Clang
  block: Enable lock context analysis

 block/Makefile             |   2 +
 block/bfq-cgroup.c         |  11 +-
 block/blk-cgroup.c         |  98 +++---------
 block/blk-cgroup.h         |  13 +-
 block/blk-crypto-profile.c |   2 +
 block/blk-iocost.c         | 302 ++++++++++++++++++++-----------------
 block/blk-iolatency.c      |  19 ++-
 block/blk-mq-debugfs.c     |  24 ++-
 block/blk-throttle.c       |  34 +++--
 block/blk.h                |   4 +
 block/kyber-iosched.c      |   7 +-
 block/mq-deadline.c        |  12 +-
 include/linux/blkdev.h     |  21 ++-
 13 files changed, 291 insertions(+), 258 deletions(-)