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Diffstat (limited to 'arch/x86/include/asm/qspinlock_paravirt.h')
-rw-r--r--arch/x86/include/asm/qspinlock_paravirt.h13
1 files changed, 7 insertions, 6 deletions
diff --git a/arch/x86/include/asm/qspinlock_paravirt.h b/arch/x86/include/asm/qspinlock_paravirt.h
index 42b17cf10b10..0a985784be9b 100644
--- a/arch/x86/include/asm/qspinlock_paravirt.h
+++ b/arch/x86/include/asm/qspinlock_paravirt.h
@@ -4,6 +4,8 @@
#include <asm/ibt.h>
+void __lockfunc __pv_queued_spin_unlock_slowpath(struct qspinlock *lock, u8 locked);
+
/*
* For x86-64, PV_CALLEE_SAVE_REGS_THUNK() saves and restores 8 64-bit
* registers. For i386, however, only 1 32-bit register needs to be saved
@@ -23,9 +25,9 @@ __PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath, ".spinlock.text");
*
* void __lockfunc __pv_queued_spin_unlock(struct qspinlock *lock)
* {
- * u8 lockval = cmpxchg(&lock->locked, _Q_LOCKED_VAL, 0);
+ * u8 lockval = _Q_LOCKED_VAL;
*
- * if (likely(lockval == _Q_LOCKED_VAL))
+ * if (try_cmpxchg(&lock->locked, &lockval, 0))
* return;
* pv_queued_spin_unlock_slowpath(lock, lockval);
* }
@@ -38,10 +40,9 @@ __PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath, ".spinlock.text");
#define PV_UNLOCK_ASM \
FRAME_BEGIN \
"push %rdx\n\t" \
- "mov $0x1,%eax\n\t" \
+ "mov $" __stringify(_Q_LOCKED_VAL) ",%eax\n\t" \
"xor %edx,%edx\n\t" \
LOCK_PREFIX "cmpxchg %dl,(%rdi)\n\t" \
- "cmp $0x1,%al\n\t" \
"jne .slowpath\n\t" \
"pop %rdx\n\t" \
FRAME_END \
@@ -54,8 +55,8 @@ __PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath, ".spinlock.text");
"pop %rdx\n\t" \
FRAME_END
-DEFINE_PARAVIRT_ASM(__raw_callee_save___pv_queued_spin_unlock,
- PV_UNLOCK_ASM, .spinlock.text);
+DEFINE_ASM_FUNC(__raw_callee_save___pv_queued_spin_unlock,
+ PV_UNLOCK_ASM, .spinlock.text);
#else /* CONFIG_64BIT */