Commit-ID: c0dc373a780f4ec63e45a573b9551763abd8cd1a Gitweb: https://git.kernel.org/tip/c0dc373a780f4ec63e45a573b9551763abd8cd1a Author: Waiman Long <long...@redhat.com> AuthorDate: Tue, 17 Jul 2018 16:16:00 -0400 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Wed, 25 Jul 2018 11:22:20 +0200
locking/pvqspinlock/x86: Use LOCK_PREFIX in __pv_queued_spin_unlock() assembly code The LOCK_PREFIX macro should be used in the __raw_callee_save___pv_queued_spin_unlock() assembly code, so that the lock prefix can be patched out on UP systems. Signed-off-by: Waiman Long <long...@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Cc: Joe Mario <jma...@redhat.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Thomas Gleixner <t...@linutronix.de> Cc: Will Deacon <will.dea...@arm.com> Link: http://lkml.kernel.org/r/1531858560-21547-1-git-send-email-long...@redhat.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/include/asm/qspinlock_paravirt.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/include/asm/qspinlock_paravirt.h b/arch/x86/include/asm/qspinlock_paravirt.h index 9ef5ee03d2d7..159622ee0674 100644 --- a/arch/x86/include/asm/qspinlock_paravirt.h +++ b/arch/x86/include/asm/qspinlock_paravirt.h @@ -43,7 +43,7 @@ asm (".pushsection .text;" "push %rdx;" "mov $0x1,%eax;" "xor %edx,%edx;" - "lock cmpxchg %dl,(%rdi);" + LOCK_PREFIX "cmpxchg %dl,(%rdi);" "cmp $0x1,%al;" "jne .slowpath;" "pop %rdx;"
