2 Commits

Author	SHA1	Message	Date
Ingo Molnar	88f182dd77	x86: Apply the asm_volatile_goto() compiler quirk ... Apply the asm_volatile_goto() compiler quirk to the new rmwcc.h file as well, introduced in: c2daa3bed5 sched, x86: Provide a per-cpu preempt_count implementation Reported-and-tested-by: Fengguang Wu <fengguang.wu@intel.com> Reported-by: Oleg Nesterov <oleg@redhat.com> Reported-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Suggested-by: Jakub Jelinek <jakub@redhat.com> Reviewed-by: Richard Henderson <rth@twiddle.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>	2013-10-11 07:41:43 +02:00
Peter Zijlstra	0c44c2d0f4	x86: Use asm goto to implement better modify_and_test() functions ... Linus suggested using asm goto to get rid of the typical SETcc + TEST instruction pair -- which also clobbers an extra register -- for our typical modify_and_test() functions. Because asm goto doesn't allow output fields it has to include an unconditinal memory clobber when it changes a memory variable to force a reload. Luckily all atomic ops already imply a compiler barrier to go along with their memory barrier semantics. Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/n/tip-0mtn9siwbeo1d33bap1422se@git.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>	2013-09-25 13:53:08 +02:00