locking/locktorture: Fix false positive circular locking splat in ww_mutex test
authorWaiman Long <longman@redhat.com>
Thu, 18 Mar 2021 17:28:11 +0000 (13:28 -0400)
committerIngo Molnar <mingo@kernel.org>
Fri, 19 Mar 2021 11:13:09 +0000 (12:13 +0100)
commit2ea55bbba23e9d36996299664d618393c8602646
treefb0fbeefffcfe8eda7c27e77fa5bc2d91d77030f
parent01438749e36bfe53ea25c91568019be775a9782e
locking/locktorture: Fix false positive circular locking splat in ww_mutex test

In order to avoid false positive circular locking lockdep splat
when runnng the ww_mutex torture test, we need to make sure that
the ww_mutexes have the same lock class as the acquire_ctx. This
means the ww_mutexes must have the same lockdep key as the
acquire_ctx. Unfortunately the current DEFINE_WW_MUTEX() macro fails
to do that. As a result, we add an init method for the ww_mutex test
to do explicit ww_mutex_init()'s of the ww_mutexes to avoid the false
positive warning.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210318172814.4400-3-longman@redhat.com
kernel/locking/locktorture.c