mirror of https://gitee.com/openkylin/linux.git
6428671bae
A while back Viro posted a number of 'interesting' mutex_is_locked() users on IRC, one of those was RCU. RCU seems to use mutex_is_locked() to avoid doing mutex_trylock(), the regular load before modify pattern. While the use isn't wrong per se, its curious in that its needed at all, mutex_trylock() should be good enough on its own to avoid the pointless cacheline bounces. So fix those and remove the mutex_is_locked() (ab)use from RCU. Reported-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Paul McKenney <paulmck@linux.vnet.ibm.com> Acked-by: Davidlohr Bueso <dave@stgolabs.net> 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: Waiman Long <Waiman.Long@hpe.com> Link: http://lkml.kernel.org/r/20160601185815.GW3190@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org> |
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| .. | ||
| Makefile | ||
| rcu.h | ||
| rcuperf.c | ||
| rcutorture.c | ||
| srcu.c | ||
| sync.c | ||
| tiny.c | ||
| tiny_plugin.h | ||
| tree.c | ||
| tree.h | ||
| tree_plugin.h | ||
| tree_trace.c | ||
| update.c | ||