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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-24 13:13:57 +08:00
linux-next/arch/powerpc
Peter Zijlstra 6428671bae locking/mutex: Optimize mutex_trylock() fast-path
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>
2016-06-08 15:17:01 +02:00
..
boot Merge branch 'for-4.7-dw' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata 2016-05-23 18:19:21 -07:00
configs powerpc updates for 4.6 2016-03-19 15:38:41 -07:00
crypto powerpc updates for 4.6 2016-03-19 15:38:41 -07:00
include locking/mutex: Optimize mutex_trylock() fast-path 2016-06-08 15:17:01 +02:00
kernel vdso: make arch_setup_additional_pages wait for mmap_sem for write killable 2016-05-23 17:04:14 -07:00
kvm powerpc updates for 4.7 2016-05-20 10:12:41 -07:00
lib powerpc/sstep: Fix emulation fall-through 2016-05-11 21:54:08 +10:00
math-emu powerpc: Correct emulated mtfsf instruction 2014-04-07 10:33:11 +10:00
mm powerpc updates for 4.7 2016-05-20 10:12:41 -07:00
net net: filter: make JITs zero A for SKF_AD_ALU_XOR_X 2016-01-06 00:43:52 -05:00
oprofile powerpc: Fix misspellings in comments. 2016-03-01 19:27:20 +11:00
perf Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-05-25 17:05:40 -07:00
platforms powerpc updates for 4.7 2016-05-20 10:12:41 -07:00
scripts powerpc/ftrace: Add Kconfig & Make glue for mprofile-kernel 2016-03-07 14:53:56 +11:00
sysdev DAX error handling for 4.7 2016-05-26 19:34:26 -07:00
xmon powerpc/xmon: Fix SPR read/write commands and add command to dump SPRs 2016-05-11 21:54:07 +10:00
Kconfig printk/nmi: generic solution for safe printk in NMI 2016-05-20 17:58:30 -07:00
Kconfig.debug powerpc/mm: Always use STRICT_MM_TYPECHECKS 2016-05-01 18:32:14 +10:00
Makefile Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next 2016-03-14 20:05:14 +11:00
relocs_check.sh powerpc: Convert relocs_check to a shell script using grep 2015-03-23 14:47:39 +11:00