Files
linux/kernel
Yuyang Du ccaa280d15 locking/lockdep: Fix lock used or unused stats error
[ Upstream commit 68d41d8c94 ]

The stats variable nr_unused_locks is incremented every time a new lock
class is register and decremented when the lock is first used in
__lock_acquire(). And after all, it is shown and checked in lockdep_stats.

However, under configurations that either CONFIG_TRACE_IRQFLAGS or
CONFIG_PROVE_LOCKING is not defined:

The commit:

  0918065151 ("locking/lockdep: Consolidate lock usage bit initialization")

missed marking the LOCK_USED flag at IRQ usage initialization because
as mark_usage() is not called. And the commit:

  886532aee3 ("locking/lockdep: Move mark_lock() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING")

further made mark_lock() not defined such that the LOCK_USED cannot be
marked at all when the lock is first acquired.

As a result, we fix this by not showing and checking the stats under such
configurations for lockdep_stats.

Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: arnd@arndb.de
Cc: frederic@kernel.org
Link: https://lkml.kernel.org/r/20190709101522.9117-1-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-08-04 09:33:42 +02:00
..
2019-08-04 09:33:19 +02:00
2017-09-02 07:07:53 +02:00
2016-01-22 18:04:28 -05:00
2016-04-04 09:46:47 -04:00
2019-05-31 06:48:20 -07:00
2015-04-12 21:03:31 +02:00
2019-01-13 10:03:51 +01:00
2015-11-23 09:44:58 +01:00
2018-08-03 07:55:12 +02:00
2016-02-16 13:04:58 -05:00
2015-01-17 10:02:23 +13:00
2016-03-01 20:36:56 +01:00
2018-08-03 07:55:24 +02:00
2018-05-09 09:50:20 +02:00
2016-09-22 20:00:36 -05:00