Commit-ID: c0dc373a780f4ec63e45a573b9551763abd8cd1a Gitweb: https://git.kernel.org/tip/c0dc373a780f4ec63e45a573b9551763abd8cd1a Author: Waiman Long <[email protected]> AuthorDate: Tue, 17 Jul 2018 16:16:00 -0400 Committer: Ingo Molnar <[email protected]> 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 <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Cc: Joe Mario <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Will Deacon <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- 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;"
