diff options
| author | Waiman Long <longman@redhat.com> | 2018-10-19 03:45:18 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-10-19 07:53:18 +0200 |
| commit | 01a14bda11add9dcd4a59200f13834d634559935 (patch) | |
| tree | c7fc12f5c710502f98bdb917d3eaf9da0943b000 | |
| parent | locking/lockdep: Fix debug_locks off performance problem (diff) | |
| download | linux-01a14bda11add9dcd4a59200f13834d634559935.tar.xz linux-01a14bda11add9dcd4a59200f13834d634559935.zip | |
locking/lockdep: Make global debug_locks* variables read-mostly
Make the frequently used lockdep global variable debug_locks read-mostly.
As debug_locks_silent is sometime used together with debug_locks,
it is also made read-mostly so that they can be close together.
With false cacheline sharing, cacheline contention problem can happen
depending on what get put into the same cacheline as debug_locks.
Signed-off-by: Waiman Long <longman@redhat.com>
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>
Link: http://lkml.kernel.org/r/1539913518-15598-2-git-send-email-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | include/linux/debug_locks.h | 4 | ||||
| -rw-r--r-- | lib/debug_locks.c | 4 |
2 files changed, 4 insertions, 4 deletions
diff --git a/include/linux/debug_locks.h b/include/linux/debug_locks.h index 120225e9a366..257ab3c92cb8 100644 --- a/include/linux/debug_locks.h +++ b/include/linux/debug_locks.h @@ -8,8 +8,8 @@ struct task_struct; -extern int debug_locks; -extern int debug_locks_silent; +extern int debug_locks __read_mostly; +extern int debug_locks_silent __read_mostly; static inline int __debug_locks_off(void) diff --git a/lib/debug_locks.c b/lib/debug_locks.c index 124fdf238b3d..ce51749cc145 100644 --- a/lib/debug_locks.c +++ b/lib/debug_locks.c @@ -21,7 +21,7 @@ * that would just muddy the log. So we report the first one and * shut up after that. */ -int debug_locks = 1; +int debug_locks __read_mostly = 1; EXPORT_SYMBOL_GPL(debug_locks); /* @@ -29,7 +29,7 @@ EXPORT_SYMBOL_GPL(debug_locks); * 'silent failure': nothing is printed to the console when * a locking bug is detected. */ -int debug_locks_silent; +int debug_locks_silent __read_mostly; EXPORT_SYMBOL_GPL(debug_locks_silent); /* |