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Diffstat (limited to 'include/asm-x86/rwsem.h')
-rw-r--r--include/asm-x86/rwsem.h169
1 files changed, 86 insertions, 83 deletions
diff --git a/include/asm-x86/rwsem.h b/include/asm-x86/rwsem.h
index 520a379f4b8..750f2a3542b 100644
--- a/include/asm-x86/rwsem.h
+++ b/include/asm-x86/rwsem.h
@@ -56,14 +56,16 @@ extern asmregparm struct rw_semaphore *
/*
* the semaphore definition
*/
-struct rw_semaphore {
- signed long count;
+
#define RWSEM_UNLOCKED_VALUE 0x00000000
#define RWSEM_ACTIVE_BIAS 0x00000001
#define RWSEM_ACTIVE_MASK 0x0000ffff
#define RWSEM_WAITING_BIAS (-0x00010000)
#define RWSEM_ACTIVE_READ_BIAS RWSEM_ACTIVE_BIAS
#define RWSEM_ACTIVE_WRITE_BIAS (RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS)
+
+struct rw_semaphore {
+ signed long count;
spinlock_t wait_lock;
struct list_head wait_list;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
@@ -78,11 +80,13 @@ struct rw_semaphore {
#endif
-#define __RWSEM_INITIALIZER(name) \
-{ RWSEM_UNLOCKED_VALUE, __SPIN_LOCK_UNLOCKED((name).wait_lock), \
- LIST_HEAD_INIT((name).wait_list) __RWSEM_DEP_MAP_INIT(name) }
+#define __RWSEM_INITIALIZER(name) \
+{ \
+ RWSEM_UNLOCKED_VALUE, __SPIN_LOCK_UNLOCKED((name).wait_lock), \
+ LIST_HEAD_INIT((name).wait_list) __RWSEM_DEP_MAP_INIT(name) \
+}
-#define DECLARE_RWSEM(name) \
+#define DECLARE_RWSEM(name) \
struct rw_semaphore name = __RWSEM_INITIALIZER(name)
extern void __init_rwsem(struct rw_semaphore *sem, const char *name,
@@ -100,16 +104,16 @@ do { \
*/
static inline void __down_read(struct rw_semaphore *sem)
{
- __asm__ __volatile__(
- "# beginning down_read\n\t"
-LOCK_PREFIX " incl (%%eax)\n\t" /* adds 0x00000001, returns the old value */
- " jns 1f\n"
- " call call_rwsem_down_read_failed\n"
- "1:\n\t"
- "# ending down_read\n\t"
- : "+m" (sem->count)
- : "a" (sem)
- : "memory", "cc");
+ asm volatile("# beginning down_read\n\t"
+ LOCK_PREFIX " incl (%%eax)\n\t"
+ /* adds 0x00000001, returns the old value */
+ " jns 1f\n"
+ " call call_rwsem_down_read_failed\n"
+ "1:\n\t"
+ "# ending down_read\n\t"
+ : "+m" (sem->count)
+ : "a" (sem)
+ : "memory", "cc");
}
/*
@@ -118,21 +122,20 @@ LOCK_PREFIX " incl (%%eax)\n\t" /* adds 0x00000001, returns the old value
static inline int __down_read_trylock(struct rw_semaphore *sem)
{
__s32 result, tmp;
- __asm__ __volatile__(
- "# beginning __down_read_trylock\n\t"
- " movl %0,%1\n\t"
- "1:\n\t"
- " movl %1,%2\n\t"
- " addl %3,%2\n\t"
- " jle 2f\n\t"
-LOCK_PREFIX " cmpxchgl %2,%0\n\t"
- " jnz 1b\n\t"
- "2:\n\t"
- "# ending __down_read_trylock\n\t"
- : "+m" (sem->count), "=&a" (result), "=&r" (tmp)
- : "i" (RWSEM_ACTIVE_READ_BIAS)
- : "memory", "cc");
- return result>=0 ? 1 : 0;
+ asm volatile("# beginning __down_read_trylock\n\t"
+ " movl %0,%1\n\t"
+ "1:\n\t"
+ " movl %1,%2\n\t"
+ " addl %3,%2\n\t"
+ " jle 2f\n\t"
+ LOCK_PREFIX " cmpxchgl %2,%0\n\t"
+ " jnz 1b\n\t"
+ "2:\n\t"
+ "# ending __down_read_trylock\n\t"
+ : "+m" (sem->count), "=&a" (result), "=&r" (tmp)
+ : "i" (RWSEM_ACTIVE_READ_BIAS)
+ : "memory", "cc");
+ return result >= 0 ? 1 : 0;
}
/*
@@ -143,17 +146,18 @@ static inline void __down_write_nested(struct rw_semaphore *sem, int subclass)
int tmp;
tmp = RWSEM_ACTIVE_WRITE_BIAS;
- __asm__ __volatile__(
- "# beginning down_write\n\t"
-LOCK_PREFIX " xadd %%edx,(%%eax)\n\t" /* subtract 0x0000ffff, returns the old value */
- " testl %%edx,%%edx\n\t" /* was the count 0 before? */
- " jz 1f\n"
- " call call_rwsem_down_write_failed\n"
- "1:\n"
- "# ending down_write"
- : "+m" (sem->count), "=d" (tmp)
- : "a" (sem), "1" (tmp)
- : "memory", "cc");
+ asm volatile("# beginning down_write\n\t"
+ LOCK_PREFIX " xadd %%edx,(%%eax)\n\t"
+ /* subtract 0x0000ffff, returns the old value */
+ " testl %%edx,%%edx\n\t"
+ /* was the count 0 before? */
+ " jz 1f\n"
+ " call call_rwsem_down_write_failed\n"
+ "1:\n"
+ "# ending down_write"
+ : "+m" (sem->count), "=d" (tmp)
+ : "a" (sem), "1" (tmp)
+ : "memory", "cc");
}
static inline void __down_write(struct rw_semaphore *sem)
@@ -167,7 +171,7 @@ static inline void __down_write(struct rw_semaphore *sem)
static inline int __down_write_trylock(struct rw_semaphore *sem)
{
signed long ret = cmpxchg(&sem->count,
- RWSEM_UNLOCKED_VALUE,
+ RWSEM_UNLOCKED_VALUE,
RWSEM_ACTIVE_WRITE_BIAS);
if (ret == RWSEM_UNLOCKED_VALUE)
return 1;
@@ -180,16 +184,16 @@ static inline int __down_write_trylock(struct rw_semaphore *sem)
static inline void __up_read(struct rw_semaphore *sem)
{
__s32 tmp = -RWSEM_ACTIVE_READ_BIAS;
- __asm__ __volatile__(
- "# beginning __up_read\n\t"
-LOCK_PREFIX " xadd %%edx,(%%eax)\n\t" /* subtracts 1, returns the old value */
- " jns 1f\n\t"
- " call call_rwsem_wake\n"
- "1:\n"
- "# ending __up_read\n"
- : "+m" (sem->count), "=d" (tmp)
- : "a" (sem), "1" (tmp)
- : "memory", "cc");
+ asm volatile("# beginning __up_read\n\t"
+ LOCK_PREFIX " xadd %%edx,(%%eax)\n\t"
+ /* subtracts 1, returns the old value */
+ " jns 1f\n\t"
+ " call call_rwsem_wake\n"
+ "1:\n"
+ "# ending __up_read\n"
+ : "+m" (sem->count), "=d" (tmp)
+ : "a" (sem), "1" (tmp)
+ : "memory", "cc");
}
/*
@@ -197,17 +201,18 @@ LOCK_PREFIX " xadd %%edx,(%%eax)\n\t" /* subtracts 1, returns the old valu
*/
static inline void __up_write(struct rw_semaphore *sem)
{
- __asm__ __volatile__(
- "# beginning __up_write\n\t"
- " movl %2,%%edx\n\t"
-LOCK_PREFIX " xaddl %%edx,(%%eax)\n\t" /* tries to transition 0xffff0001 -> 0x00000000 */
- " jz 1f\n"
- " call call_rwsem_wake\n"
- "1:\n\t"
- "# ending __up_write\n"
- : "+m" (sem->count)
- : "a" (sem), "i" (-RWSEM_ACTIVE_WRITE_BIAS)
- : "memory", "cc", "edx");
+ asm volatile("# beginning __up_write\n\t"
+ " movl %2,%%edx\n\t"
+ LOCK_PREFIX " xaddl %%edx,(%%eax)\n\t"
+ /* tries to transition
+ 0xffff0001 -> 0x00000000 */
+ " jz 1f\n"
+ " call call_rwsem_wake\n"
+ "1:\n\t"
+ "# ending __up_write\n"
+ : "+m" (sem->count)
+ : "a" (sem), "i" (-RWSEM_ACTIVE_WRITE_BIAS)
+ : "memory", "cc", "edx");
}
/*
@@ -215,16 +220,16 @@ LOCK_PREFIX " xaddl %%edx,(%%eax)\n\t" /* tries to transition 0xffff0001 ->
*/
static inline void __downgrade_write(struct rw_semaphore *sem)
{
- __asm__ __volatile__(
- "# beginning __downgrade_write\n\t"
-LOCK_PREFIX " addl %2,(%%eax)\n\t" /* transitions 0xZZZZ0001 -> 0xYYYY0001 */
- " jns 1f\n\t"
- " call call_rwsem_downgrade_wake\n"
- "1:\n\t"
- "# ending __downgrade_write\n"
- : "+m" (sem->count)
- : "a" (sem), "i" (-RWSEM_WAITING_BIAS)
- : "memory", "cc");
+ asm volatile("# beginning __downgrade_write\n\t"
+ LOCK_PREFIX " addl %2,(%%eax)\n\t"
+ /* transitions 0xZZZZ0001 -> 0xYYYY0001 */
+ " jns 1f\n\t"
+ " call call_rwsem_downgrade_wake\n"
+ "1:\n\t"
+ "# ending __downgrade_write\n"
+ : "+m" (sem->count)
+ : "a" (sem), "i" (-RWSEM_WAITING_BIAS)
+ : "memory", "cc");
}
/*
@@ -232,10 +237,9 @@ LOCK_PREFIX " addl %2,(%%eax)\n\t" /* transitions 0xZZZZ0001 -> 0xYYYY0001
*/
static inline void rwsem_atomic_add(int delta, struct rw_semaphore *sem)
{
- __asm__ __volatile__(
-LOCK_PREFIX "addl %1,%0"
- : "+m" (sem->count)
- : "ir" (delta));
+ asm volatile(LOCK_PREFIX "addl %1,%0"
+ : "+m" (sem->count)
+ : "ir" (delta));
}
/*
@@ -245,12 +249,11 @@ static inline int rwsem_atomic_update(int delta, struct rw_semaphore *sem)
{
int tmp = delta;
- __asm__ __volatile__(
-LOCK_PREFIX "xadd %0,%1"
- : "+r" (tmp), "+m" (sem->count)
- : : "memory");
+ asm volatile(LOCK_PREFIX "xadd %0,%1"
+ : "+r" (tmp), "+m" (sem->count)
+ : : "memory");
- return tmp+delta;
+ return tmp + delta;
}
static inline int rwsem_is_locked(struct rw_semaphore *sem)
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-18 15:09:40 +0000