X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-x86_64%2Fspinlock.h;h=88bf981e73cf45c084c66d6d60c25e066fa53340;hb=refs%2Fheads%2Fvserver;hp=fe484a699cc3609cca9d1c592e17624bd7bd22a8;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git

diff --git a/include/asm-x86_64/spinlock.h b/include/asm-x86_64/spinlock.h
index fe484a699..88bf981e7 100644
--- a/include/asm-x86_64/spinlock.h
+++ b/include/asm-x86_64/spinlock.h
@@ -4,7 +4,7 @@
 #include <asm/atomic.h>
 #include <asm/rwlock.h>
 #include <asm/page.h>
-#include <linux/config.h>
+#include <asm/processor.h>
 
 /*
  * Your basic SMP spinlocks, allowing only a single CPU anywhere
@@ -17,39 +17,59 @@
  * (the type definitions are in asm/spinlock_types.h)
  */
 
-#define __raw_spin_is_locked(x) \
-		(*(volatile signed int *)(&(x)->slock) <= 0)
-
-#define __raw_spin_lock_string \
-	"\n1:\t" \
-	"lock ; decl %0\n\t" \
-	"js 2f\n" \
-	LOCK_SECTION_START("") \
-	"2:\t" \
-	"rep;nop\n\t" \
-	"cmpl $0,%0\n\t" \
-	"jle 2b\n\t" \
-	"jmp 1b\n" \
-	LOCK_SECTION_END
-
-#define __raw_spin_unlock_string \
-	"movl $1,%0" \
-		:"=m" (lock->slock) : : "memory"
+static inline int __raw_spin_is_locked(raw_spinlock_t *lock)
+{
+	return *(volatile signed int *)(&(lock)->slock) <= 0;
+}
 
 static inline void __raw_spin_lock(raw_spinlock_t *lock)
 {
-	__asm__ __volatile__(
-		__raw_spin_lock_string
-		:"=m" (lock->slock) : : "memory");
+	asm volatile(
+		"\n1:\t"
+		LOCK_PREFIX " ; decl %0\n\t"
+		"jns 2f\n"
+		"3:\n"
+		"rep;nop\n\t"
+		"cmpl $0,%0\n\t"
+		"jle 3b\n\t"
+		"jmp 1b\n"
+		"2:\t" : "=m" (lock->slock) : : "memory");
 }
 
-#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
+/*
+ * Same as __raw_spin_lock, but reenable interrupts during spinning.
+ */
+#ifndef CONFIG_PROVE_LOCKING
+static inline void __raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long flags)
+{
+	asm volatile(
+		"\n1:\t"
+		LOCK_PREFIX " ; decl %0\n\t"
+		"jns 5f\n"
+		"testl $0x200, %1\n\t"	/* interrupts were disabled? */
+		"jz 4f\n\t"
+	        "sti\n"
+		"3:\t"
+		"rep;nop\n\t"
+		"cmpl $0, %0\n\t"
+		"jle 3b\n\t"
+		"cli\n\t"
+		"jmp 1b\n"
+		"4:\t"
+		"rep;nop\n\t"
+		"cmpl $0, %0\n\t"
+		"jg 1b\n\t"
+		"jmp 4b\n"
+		"5:\n\t"
+		: "+m" (lock->slock) : "r" ((unsigned)flags) : "memory");
+}
+#endif
 
 static inline int __raw_spin_trylock(raw_spinlock_t *lock)
 {
 	int oldval;
 
-	__asm__ __volatile__(
+	asm volatile(
 		"xchgl %0,%1"
 		:"=q" (oldval), "=m" (lock->slock)
 		:"0" (0) : "memory");
@@ -59,13 +79,14 @@ static inline int __raw_spin_trylock(raw_spinlock_t *lock)
 
 static inline void __raw_spin_unlock(raw_spinlock_t *lock)
 {
-	__asm__ __volatile__(
-		__raw_spin_unlock_string
-	);
+	asm volatile("movl $1,%0" :"=m" (lock->slock) :: "memory");
 }
 
-#define __raw_spin_unlock_wait(lock) \
-	do { while (__raw_spin_is_locked(lock)) cpu_relax(); } while (0)
+static inline void __raw_spin_unlock_wait(raw_spinlock_t *lock)
+{
+	while (__raw_spin_is_locked(lock))
+		cpu_relax();
+}
 
 /*
  * Read-write spinlocks, allowing multiple readers
@@ -79,26 +100,34 @@ static inline void __raw_spin_unlock(raw_spinlock_t *lock)
  *
  * On x86, we implement read-write locks as a 32-bit counter
  * with the high bit (sign) being the "contended" bit.
- *
- * The inline assembly is non-obvious. Think about it.
- *
- * Changed to use the same technique as rw semaphores.  See
- * semaphore.h for details.  -ben
- *
- * the helpers are in arch/i386/kernel/semaphore.c
  */
 
-#define __raw_read_can_lock(x)		((int)(x)->lock > 0)
-#define __raw_write_can_lock(x)		((x)->lock == RW_LOCK_BIAS)
+static inline int __raw_read_can_lock(raw_rwlock_t *lock)
+{
+	return (int)(lock)->lock > 0;
+}
+
+static inline int __raw_write_can_lock(raw_rwlock_t *lock)
+{
+	return (lock)->lock == RW_LOCK_BIAS;
+}
 
 static inline void __raw_read_lock(raw_rwlock_t *rw)
 {
-	__build_read_lock(rw, "__read_lock_failed");
+	asm volatile(LOCK_PREFIX "subl $1,(%0)\n\t"
+		     "jns 1f\n"
+		     "call __read_lock_failed\n"
+		     "1:\n"
+		     ::"D" (rw), "i" (RW_LOCK_BIAS) : "memory");
 }
 
 static inline void __raw_write_lock(raw_rwlock_t *rw)
 {
-	__build_write_lock(rw, "__write_lock_failed");
+	asm volatile(LOCK_PREFIX "subl %1,(%0)\n\t"
+		     "jz 1f\n"
+		     "\tcall __write_lock_failed\n\t"
+		     "1:\n"
+		     ::"D" (rw), "i" (RW_LOCK_BIAS) : "memory");
 }
 
 static inline int __raw_read_trylock(raw_rwlock_t *lock)
@@ -122,13 +151,17 @@ static inline int __raw_write_trylock(raw_rwlock_t *lock)
 
 static inline void __raw_read_unlock(raw_rwlock_t *rw)
 {
-	asm volatile("lock ; incl %0" :"=m" (rw->lock) : : "memory");
+	asm volatile(LOCK_PREFIX " ; incl %0" :"=m" (rw->lock) : : "memory");
 }
 
 static inline void __raw_write_unlock(raw_rwlock_t *rw)
 {
-	asm volatile("lock ; addl $" RW_LOCK_BIAS_STR ",%0"
+	asm volatile(LOCK_PREFIX " ; addl $" RW_LOCK_BIAS_STR ",%0"
 				: "=m" (rw->lock) : : "memory");
 }
 
+#define _raw_spin_relax(lock)	cpu_relax()
+#define _raw_read_relax(lock)	cpu_relax()
+#define _raw_write_relax(lock)	cpu_relax()
+
 #endif /* __ASM_SPINLOCK_H */