[ARM] 3311/1: clean up include/asm-arm/mutex.h
Patch from Nicolas Pitre
Since:
if (unlikely(__res || __ex_flag))
produces worse code on ARM than:
if (unlikely(__res | __ex_flag))
I therefore made it more explicit:
__res |= __ex_flag;
if (unlikely(__res != 0))
so it is not seen as a typo again.
Also made everything static inline rather than macros for better readability
(both produce the same code after all).
And finally added missing \t from multi-line assembly code.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/include/asm-arm/mutex.h b/include/asm-arm/mutex.h
index 6caa59f..cb29d84 100644
--- a/include/asm-arm/mutex.h
+++ b/include/asm-arm/mutex.h
@@ -23,72 +23,71 @@
* simply bail out immediately through the slow path where the lock will be
* reattempted until it succeeds.
*/
-#define __mutex_fastpath_lock(count, fail_fn) \
-do { \
- int __ex_flag, __res; \
- \
- typecheck(atomic_t *, count); \
- typecheck_fn(fastcall void (*)(atomic_t *), fail_fn); \
- \
- __asm__ ( \
- "ldrex %0, [%2] \n" \
- "sub %0, %0, #1 \n" \
- "strex %1, %0, [%2] \n" \
- \
- : "=&r" (__res), "=&r" (__ex_flag) \
- : "r" (&(count)->counter) \
- : "cc","memory" ); \
- \
- if (unlikely(__res || __ex_flag)) \
- fail_fn(count); \
-} while (0)
+static inline void
+__mutex_fastpath_lock(atomic_t *count, fastcall void (*fail_fn)(atomic_t *))
+{
+ int __ex_flag, __res;
-#define __mutex_fastpath_lock_retval(count, fail_fn) \
-({ \
- int __ex_flag, __res; \
- \
- typecheck(atomic_t *, count); \
- typecheck_fn(fastcall int (*)(atomic_t *), fail_fn); \
- \
- __asm__ ( \
- "ldrex %0, [%2] \n" \
- "sub %0, %0, #1 \n" \
- "strex %1, %0, [%2] \n" \
- \
- : "=&r" (__res), "=&r" (__ex_flag) \
- : "r" (&(count)->counter) \
- : "cc","memory" ); \
- \
- __res |= __ex_flag; \
- if (unlikely(__res != 0)) \
- __res = fail_fn(count); \
- __res; \
-})
+ __asm__ (
+
+ "ldrex %0, [%2] \n\t"
+ "sub %0, %0, #1 \n\t"
+ "strex %1, %0, [%2] "
+
+ : "=&r" (__res), "=&r" (__ex_flag)
+ : "r" (&(count)->counter)
+ : "cc","memory" );
+
+ __res |= __ex_flag;
+ if (unlikely(__res != 0))
+ fail_fn(count);
+}
+
+static inline int
+__mutex_fastpath_lock_retval(atomic_t *count, fastcall int (*fail_fn)(atomic_t *))
+{
+ int __ex_flag, __res;
+
+ __asm__ (
+
+ "ldrex %0, [%2] \n\t"
+ "sub %0, %0, #1 \n\t"
+ "strex %1, %0, [%2] "
+
+ : "=&r" (__res), "=&r" (__ex_flag)
+ : "r" (&(count)->counter)
+ : "cc","memory" );
+
+ __res |= __ex_flag;
+ if (unlikely(__res != 0))
+ __res = fail_fn(count);
+ return __res;
+}
/*
* Same trick is used for the unlock fast path. However the original value,
* rather than the result, is used to test for success in order to have
* better generated assembly.
*/
-#define __mutex_fastpath_unlock(count, fail_fn) \
-do { \
- int __ex_flag, __res, __orig; \
- \
- typecheck(atomic_t *, count); \
- typecheck_fn(fastcall void (*)(atomic_t *), fail_fn); \
- \
- __asm__ ( \
- "ldrex %0, [%3] \n" \
- "add %1, %0, #1 \n" \
- "strex %2, %1, [%3] \n" \
- \
- : "=&r" (__orig), "=&r" (__res), "=&r" (__ex_flag) \
- : "r" (&(count)->counter) \
- : "cc","memory" ); \
- \
- if (unlikely(__orig || __ex_flag)) \
- fail_fn(count); \
-} while (0)
+static inline void
+__mutex_fastpath_unlock(atomic_t *count, fastcall void (*fail_fn)(atomic_t *))
+{
+ int __ex_flag, __res, __orig;
+
+ __asm__ (
+
+ "ldrex %0, [%3] \n\t"
+ "add %1, %0, #1 \n\t"
+ "strex %2, %1, [%3] "
+
+ : "=&r" (__orig), "=&r" (__res), "=&r" (__ex_flag)
+ : "r" (&(count)->counter)
+ : "cc","memory" );
+
+ __orig |= __ex_flag;
+ if (unlikely(__orig != 0))
+ fail_fn(count);
+}
/*
* If the unlock was done on a contended lock, or if the unlock simply fails
@@ -110,12 +109,12 @@
__asm__ (
- "1: ldrex %0, [%3] \n"
- "subs %1, %0, #1 \n"
- "strexeq %2, %1, [%3] \n"
- "movlt %0, #0 \n"
- "cmpeq %2, #0 \n"
- "bgt 1b \n"
+ "1: ldrex %0, [%3] \n\t"
+ "subs %1, %0, #1 \n\t"
+ "strexeq %2, %1, [%3] \n\t"
+ "movlt %0, #0 \n\t"
+ "cmpeq %2, #0 \n\t"
+ "bgt 1b "
: "=&r" (__orig), "=&r" (__res), "=&r" (__ex_flag)
: "r" (&count->counter)