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-rw-r--r--arch/i386/lib/semaphore.S63
-rw-r--r--include/asm-i386/rwsem.h62
2 files changed, 75 insertions, 50 deletions
diff --git a/arch/i386/lib/semaphore.S b/arch/i386/lib/semaphore.S
index e16ff16..01f80b5 100644
--- a/arch/i386/lib/semaphore.S
+++ b/arch/i386/lib/semaphore.S
@@ -152,3 +152,66 @@ ENTRY(__read_lock_failed)
END(__read_lock_failed)
#endif
+
+/* Fix up special calling conventions */
+ENTRY(call_rwsem_down_read_failed)
+ CFI_STARTPROC
+ push %ecx
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET ecx,0
+ push %edx
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET edx,0
+ call rwsem_down_read_failed
+ pop %edx
+ CFI_ADJUST_CFA_OFFSET -4
+ pop %ecx
+ CFI_ADJUST_CFA_OFFSET -4
+ ret
+ CFI_ENDPROC
+ END(call_rwsem_down_read_failed)
+
+ENTRY(call_rwsem_down_write_failed)
+ CFI_STARTPROC
+ push %ecx
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET ecx,0
+ calll rwsem_down_write_failed
+ pop %ecx
+ CFI_ADJUST_CFA_OFFSET -4
+ ret
+ CFI_ENDPROC
+ END(call_rwsem_down_write_failed)
+
+ENTRY(call_rwsem_wake)
+ CFI_STARTPROC
+ decw %dx /* do nothing if still outstanding active readers */
+ jnz 1f
+ push %ecx
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET ecx,0
+ call rwsem_wake
+ pop %ecx
+ CFI_ADJUST_CFA_OFFSET -4
+1: ret
+ CFI_ENDPROC
+ END(call_rwsem_wake)
+
+/* Fix up special calling conventions */
+ENTRY(call_rwsem_downgrade_wake)
+ CFI_STARTPROC
+ push %ecx
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET ecx,0
+ push %edx
+ CFI_ADJUST_CFA_OFFSET 4
+ CFI_REL_OFFSET edx,0
+ call rwsem_downgrade_wake
+ pop %edx
+ CFI_ADJUST_CFA_OFFSET -4
+ pop %ecx
+ CFI_ADJUST_CFA_OFFSET -4
+ ret
+ CFI_ENDPROC
+ END(call_rwsem_downgrade_wake)
+
diff --git a/include/asm-i386/rwsem.h b/include/asm-i386/rwsem.h
index 43113f5..bc598d6 100644
--- a/include/asm-i386/rwsem.h
+++ b/include/asm-i386/rwsem.h
@@ -99,17 +99,9 @@ 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 */
- " js 2f\n\t" /* jump if we weren't granted the lock */
+ " jns 1f\n"
+ " call call_rwsem_down_read_failed\n"
"1:\n\t"
- LOCK_SECTION_START("")
- "2:\n\t"
- " pushl %%ecx\n\t"
- " pushl %%edx\n\t"
- " call rwsem_down_read_failed\n\t"
- " popl %%edx\n\t"
- " popl %%ecx\n\t"
- " jmp 1b\n"
- LOCK_SECTION_END
"# ending down_read\n\t"
: "+m" (sem->count)
: "a" (sem)
@@ -151,15 +143,9 @@ static inline void __down_write_nested(struct rw_semaphore *sem, int subclass)
"# 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? */
- " jnz 2f\n\t" /* jump if we weren't granted the lock */
- "1:\n\t"
- LOCK_SECTION_START("")
- "2:\n\t"
- " pushl %%ecx\n\t"
- " call rwsem_down_write_failed\n\t"
- " popl %%ecx\n\t"
- " jmp 1b\n"
- LOCK_SECTION_END
+ " jz 1f\n"
+ " call call_rwsem_down_write_failed\n"
+ "1:\n"
"# ending down_write"
: "+m" (sem->count), "=d" (tmp)
: "a" (sem), "1" (tmp)
@@ -193,17 +179,9 @@ static inline void __up_read(struct rw_semaphore *sem)
__asm__ __volatile__(
"# beginning __up_read\n\t"
LOCK_PREFIX " xadd %%edx,(%%eax)\n\t" /* subtracts 1, returns the old value */
- " js 2f\n\t" /* jump if the lock is being waited upon */
- "1:\n\t"
- LOCK_SECTION_START("")
- "2:\n\t"
- " decw %%dx\n\t" /* do nothing if still outstanding active readers */
- " jnz 1b\n\t"
- " pushl %%ecx\n\t"
- " call rwsem_wake\n\t"
- " popl %%ecx\n\t"
- " jmp 1b\n"
- LOCK_SECTION_END
+ " jns 1f\n\t"
+ " call call_rwsem_wake\n"
+ "1:\n"
"# ending __up_read\n"
: "+m" (sem->count), "=d" (tmp)
: "a" (sem), "1" (tmp)
@@ -219,17 +197,9 @@ static inline void __up_write(struct rw_semaphore *sem)
"# beginning __up_write\n\t"
" movl %2,%%edx\n\t"
LOCK_PREFIX " xaddl %%edx,(%%eax)\n\t" /* tries to transition 0xffff0001 -> 0x00000000 */
- " jnz 2f\n\t" /* jump if the lock is being waited upon */
+ " jz 1f\n"
+ " call call_rwsem_wake\n"
"1:\n\t"
- LOCK_SECTION_START("")
- "2:\n\t"
- " decw %%dx\n\t" /* did the active count reduce to 0? */
- " jnz 1b\n\t" /* jump back if not */
- " pushl %%ecx\n\t"
- " call rwsem_wake\n\t"
- " popl %%ecx\n\t"
- " jmp 1b\n"
- LOCK_SECTION_END
"# ending __up_write\n"
: "+m" (sem->count)
: "a" (sem), "i" (-RWSEM_ACTIVE_WRITE_BIAS)
@@ -244,17 +214,9 @@ 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 */
- " js 2f\n\t" /* jump if the lock is being waited upon */
+ " jns 1f\n\t"
+ " call call_rwsem_downgrade_wake\n"
"1:\n\t"
- LOCK_SECTION_START("")
- "2:\n\t"
- " pushl %%ecx\n\t"
- " pushl %%edx\n\t"
- " call rwsem_downgrade_wake\n\t"
- " popl %%edx\n\t"
- " popl %%ecx\n\t"
- " jmp 1b\n"
- LOCK_SECTION_END
"# ending __downgrade_write\n"
: "+m" (sem->count)
: "a" (sem), "i" (-RWSEM_WAITING_BIAS)
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