diff options
Diffstat (limited to 'arch/x86/include/asm/rwsem.h')
| -rw-r--r-- | arch/x86/include/asm/rwsem.h | 84 |
1 files changed, 50 insertions, 34 deletions
diff --git a/arch/x86/include/asm/rwsem.h b/arch/x86/include/asm/rwsem.h index 4d38d85a16ad..4c25cf6caefa 100644 --- a/arch/x86/include/asm/rwsem.h +++ b/arch/x86/include/asm/rwsem.h @@ -61,18 +61,33 @@ /* * lock for reading */ +#define ____down_read(sem, slow_path) \ +({ \ + struct rw_semaphore* ret; \ + asm volatile("# beginning down_read\n\t" \ + LOCK_PREFIX _ASM_INC "(%[sem])\n\t" \ + /* adds 0x00000001 */ \ + " jns 1f\n" \ + " call " slow_path "\n" \ + "1:\n\t" \ + "# ending down_read\n\t" \ + : "+m" (sem->count), "=a" (ret), \ + ASM_CALL_CONSTRAINT \ + : [sem] "a" (sem) \ + : "memory", "cc"); \ + ret; \ +}) + static inline void __down_read(struct rw_semaphore *sem) { - asm volatile("# beginning down_read\n\t" - LOCK_PREFIX _ASM_INC "(%1)\n\t" - /* adds 0x00000001 */ - " 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"); + ____down_read(sem, "call_rwsem_down_read_failed"); +} + +static inline int __down_read_killable(struct rw_semaphore *sem) +{ + if (IS_ERR(____down_read(sem, "call_rwsem_down_read_failed_killable"))) + return -EINTR; + return 0; } /* @@ -82,17 +97,18 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem) { long result, tmp; asm volatile("# beginning __down_read_trylock\n\t" - " mov %0,%1\n\t" + " mov %[count],%[result]\n\t" "1:\n\t" - " mov %1,%2\n\t" - " add %3,%2\n\t" + " mov %[result],%[tmp]\n\t" + " add %[inc],%[tmp]\n\t" " jle 2f\n\t" - LOCK_PREFIX " cmpxchg %2,%0\n\t" + LOCK_PREFIX " cmpxchg %[tmp],%[count]\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) + : [count] "+m" (sem->count), [result] "=&a" (result), + [tmp] "=&r" (tmp) + : [inc] "i" (RWSEM_ACTIVE_READ_BIAS) : "memory", "cc"); return result >= 0; } @@ -106,7 +122,7 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem) struct rw_semaphore* ret; \ \ asm volatile("# beginning down_write\n\t" \ - LOCK_PREFIX " xadd %1,(%4)\n\t" \ + LOCK_PREFIX " xadd %[tmp],(%[sem])\n\t" \ /* adds 0xffff0001, returns the old value */ \ " test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t" \ /* was the active mask 0 before? */\ @@ -114,9 +130,9 @@ static inline bool __down_read_trylock(struct rw_semaphore *sem) " call " slow_path "\n" \ "1:\n" \ "# ending down_write" \ - : "+m" (sem->count), "=d" (tmp), \ + : "+m" (sem->count), [tmp] "=d" (tmp), \ "=a" (ret), ASM_CALL_CONSTRAINT \ - : "a" (sem), "1" (RWSEM_ACTIVE_WRITE_BIAS) \ + : [sem] "a" (sem), "[tmp]" (RWSEM_ACTIVE_WRITE_BIAS) \ : "memory", "cc"); \ ret; \ }) @@ -142,21 +158,21 @@ static inline bool __down_write_trylock(struct rw_semaphore *sem) bool result; long tmp0, tmp1; asm volatile("# beginning __down_write_trylock\n\t" - " mov %0,%1\n\t" + " mov %[count],%[tmp0]\n\t" "1:\n\t" " test " __ASM_SEL(%w1,%k1) "," __ASM_SEL(%w1,%k1) "\n\t" /* was the active mask 0 before? */ " jnz 2f\n\t" - " mov %1,%2\n\t" - " add %4,%2\n\t" - LOCK_PREFIX " cmpxchg %2,%0\n\t" + " mov %[tmp0],%[tmp1]\n\t" + " add %[inc],%[tmp1]\n\t" + LOCK_PREFIX " cmpxchg %[tmp1],%[count]\n\t" " jnz 1b\n\t" "2:\n\t" CC_SET(e) "# ending __down_write_trylock\n\t" - : "+m" (sem->count), "=&a" (tmp0), "=&r" (tmp1), - CC_OUT(e) (result) - : "er" (RWSEM_ACTIVE_WRITE_BIAS) + : [count] "+m" (sem->count), [tmp0] "=&a" (tmp0), + [tmp1] "=&r" (tmp1), CC_OUT(e) (result) + : [inc] "er" (RWSEM_ACTIVE_WRITE_BIAS) : "memory"); return result; } @@ -168,14 +184,14 @@ static inline void __up_read(struct rw_semaphore *sem) { long tmp; asm volatile("# beginning __up_read\n\t" - LOCK_PREFIX " xadd %1,(%2)\n\t" + LOCK_PREFIX " xadd %[tmp],(%[sem])\n\t" /* subtracts 1, returns the old value */ " jns 1f\n\t" " call call_rwsem_wake\n" /* expects old value in %edx */ "1:\n" "# ending __up_read\n" - : "+m" (sem->count), "=d" (tmp) - : "a" (sem), "1" (-RWSEM_ACTIVE_READ_BIAS) + : "+m" (sem->count), [tmp] "=d" (tmp) + : [sem] "a" (sem), "[tmp]" (-RWSEM_ACTIVE_READ_BIAS) : "memory", "cc"); } @@ -186,14 +202,14 @@ static inline void __up_write(struct rw_semaphore *sem) { long tmp; asm volatile("# beginning __up_write\n\t" - LOCK_PREFIX " xadd %1,(%2)\n\t" + LOCK_PREFIX " xadd %[tmp],(%[sem])\n\t" /* subtracts 0xffff0001, returns the old value */ " jns 1f\n\t" " call call_rwsem_wake\n" /* expects old value in %edx */ "1:\n\t" "# ending __up_write\n" - : "+m" (sem->count), "=d" (tmp) - : "a" (sem), "1" (-RWSEM_ACTIVE_WRITE_BIAS) + : "+m" (sem->count), [tmp] "=d" (tmp) + : [sem] "a" (sem), "[tmp]" (-RWSEM_ACTIVE_WRITE_BIAS) : "memory", "cc"); } @@ -203,7 +219,7 @@ static inline void __up_write(struct rw_semaphore *sem) static inline void __downgrade_write(struct rw_semaphore *sem) { asm volatile("# beginning __downgrade_write\n\t" - LOCK_PREFIX _ASM_ADD "%2,(%1)\n\t" + LOCK_PREFIX _ASM_ADD "%[inc],(%[sem])\n\t" /* * transitions 0xZZZZ0001 -> 0xYYYY0001 (i386) * 0xZZZZZZZZ00000001 -> 0xYYYYYYYY00000001 (x86_64) @@ -213,7 +229,7 @@ static inline void __downgrade_write(struct rw_semaphore *sem) "1:\n\t" "# ending __downgrade_write\n" : "+m" (sem->count) - : "a" (sem), "er" (-RWSEM_WAITING_BIAS) + : [sem] "a" (sem), [inc] "er" (-RWSEM_WAITING_BIAS) : "memory", "cc"); } |