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Diffstat (limited to 'arch/x86/include/asm/qspinlock_paravirt.h')
-rw-r--r--arch/x86/include/asm/qspinlock_paravirt.h64
1 files changed, 31 insertions, 33 deletions
diff --git a/arch/x86/include/asm/qspinlock_paravirt.h b/arch/x86/include/asm/qspinlock_paravirt.h
index 159622ee0674..0a985784be9b 100644
--- a/arch/x86/include/asm/qspinlock_paravirt.h
+++ b/arch/x86/include/asm/qspinlock_paravirt.h
@@ -2,6 +2,10 @@
#ifndef __ASM_QSPINLOCK_PARAVIRT_H
#define __ASM_QSPINLOCK_PARAVIRT_H
+#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
@@ -10,21 +14,20 @@
*/
#ifdef CONFIG_64BIT
-PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath);
+__PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath, ".spinlock.text");
#define __pv_queued_spin_unlock __pv_queued_spin_unlock
-#define PV_UNLOCK "__raw_callee_save___pv_queued_spin_unlock"
-#define PV_UNLOCK_SLOWPATH "__raw_callee_save___pv_queued_spin_unlock_slowpath"
/*
* Optimized assembly version of __raw_callee_save___pv_queued_spin_unlock
* which combines the registers saving trunk and the body of the following
- * C code:
+ * C code. Note that it puts the code in the .spinlock.text section which
+ * is equivalent to adding __lockfunc in the C code:
*
- * void __pv_queued_spin_unlock(struct qspinlock *lock)
+ * 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);
* }
@@ -34,36 +37,31 @@ PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock_slowpath);
* rsi = lockval (second argument)
* rdx = internal variable (set to 0)
*/
-asm (".pushsection .text;"
- ".globl " PV_UNLOCK ";"
- ".type " PV_UNLOCK ", @function;"
- ".align 4,0x90;"
- PV_UNLOCK ": "
- FRAME_BEGIN
- "push %rdx;"
- "mov $0x1,%eax;"
- "xor %edx,%edx;"
- LOCK_PREFIX "cmpxchg %dl,(%rdi);"
- "cmp $0x1,%al;"
- "jne .slowpath;"
- "pop %rdx;"
+#define PV_UNLOCK_ASM \
+ FRAME_BEGIN \
+ "push %rdx\n\t" \
+ "mov $" __stringify(_Q_LOCKED_VAL) ",%eax\n\t" \
+ "xor %edx,%edx\n\t" \
+ LOCK_PREFIX "cmpxchg %dl,(%rdi)\n\t" \
+ "jne .slowpath\n\t" \
+ "pop %rdx\n\t" \
+ FRAME_END \
+ ASM_RET \
+ ".slowpath:\n\t" \
+ "push %rsi\n\t" \
+ "movzbl %al,%esi\n\t" \
+ "call __raw_callee_save___pv_queued_spin_unlock_slowpath\n\t" \
+ "pop %rsi\n\t" \
+ "pop %rdx\n\t" \
FRAME_END
- "ret;"
- ".slowpath: "
- "push %rsi;"
- "movzbl %al,%esi;"
- "call " PV_UNLOCK_SLOWPATH ";"
- "pop %rsi;"
- "pop %rdx;"
- FRAME_END
- "ret;"
- ".size " PV_UNLOCK ", .-" PV_UNLOCK ";"
- ".popsection");
+
+DEFINE_ASM_FUNC(__raw_callee_save___pv_queued_spin_unlock,
+ PV_UNLOCK_ASM, .spinlock.text);
#else /* CONFIG_64BIT */
-extern void __pv_queued_spin_unlock(struct qspinlock *lock);
-PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock);
+extern void __lockfunc __pv_queued_spin_unlock(struct qspinlock *lock);
+__PV_CALLEE_SAVE_REGS_THUNK(__pv_queued_spin_unlock, ".spinlock.text");
#endif /* CONFIG_64BIT */
#endif