Re: [PATCH 00/17] Support for read-write lock deadlock detection

From: Yuyang Du
Date: Mon May 13 2019 - 05:19:19 EST


Sorry, forgot to mention the patchset is based on my previous small
improvements:

[PATCH v2 00/23] locking/lockdep: Small improvements
(https://lkml.org/lkml/2019/5/6/106).

On Mon, 13 May 2019 at 17:13, Yuyang Du <duyuyang@xxxxxxxxx> wrote:
>
> Hi Peter and Ingo,
>
> Historically, the read-write locks (recursive-read locks included) are not
> well supported in lockdep. This patchset attempts to solve this problem
> sound and complete.
>
> The bulk of the algorithm is in patch #10, which is actually not complex at
> all. Hopefully, it simply works.
>
> Now that we have read-write locks suppported, we have all the 262 cases
> passed, though I have to flip some cases which, I think, are wrong.
>
> P.S. To Boqun, I haven't got time to read your patchset except that I did
> carefully read your design doc and learnt from it a lot. It is helpful.
> Please give this patchset at least a look.
>
> Thanks,
> Yuyang
>
> --
>
> Yuyang Du (17):
> locking/lockdep: Add lock type enum to explicitly specify read or
> write locks
> locking/lockdep: Add read-write type for dependency
> locking/lockdep: Add helper functions to operate on the searched path
> locking/lockdep: Update direct dependency's read-write type if it
> exists
> locking/lockdep: Rename deadlock check functions
> locking/lockdep: Adjust BFS algorithm to support multiple matches
> locking/lockdep: Introduce mark_lock_unaccessed()
> locking/lockdep: Introduce chain_hlocks_type for held lock's
> read-write type
> locking/lockdep: Hash held lock's read-write type into chain key
> locking/lockdep: Support read-write lock's deadlock detection
> locking/lockdep: Adjust lockdep selftest cases
> locking/lockdep: Remove useless lock type assignment
> locking/lockdep: Add nest lock type
> locking/lockdep: Support recursive read locks
> locking/lockdep: Adjust selftest case for recursive read lock
> locking/lockdep: Add more lockdep selftest cases
> locking/lockdep: Remove irq-safe to irq-unsafe read check
>
> include/linux/lockdep.h | 40 +-
> kernel/locking/lockdep.c | 454 +++++++++++----
> kernel/locking/lockdep_internals.h | 4 +
> lib/locking-selftest.c | 1099 +++++++++++++++++++++++++++++++++++-
> 4 files changed, 1464 insertions(+), 133 deletions(-)
>
> --
> 1.8.3.1
>