sched/wait: Introduce ___wait_event()

There's far too much duplication in the __wait_event macros; in order to fix this introduce ___wait_event() a macro with the capability to replace most other macros. With the previous patches changing the various __wait_event*() implementations to be more uniform; we can now collapse the lot without also changing generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.181897111@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>

sched/wait: Introduce ___wait_event()
There's far too much duplication in the __wait_event macros; in order to fix this introduce ___wait_event() a macro with the capability to replace most other macros. With the previous patches changing the various __wait_event*() implementations to be more uniform; we can now collapse the lot without also changing generated code. Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20131002092528.181897111@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Peter Zijlstra · Ingo Molnar
1 parent bb632bc449
Showing 1 changed file with 36 additions and 0 deletions Side-by-side Diff
include/linux/wait.h
@@ -187,6 +187,42 @@
  	__cond || !ret;							\
 })
  
+#define ___wait_signal_pending(state)					\
+	((state == TASK_INTERRUPTIBLE && signal_pending(current)) ||	\
+	 (state == TASK_KILLABLE && fatal_signal_pending(current)))
+
+#define ___wait_nop_ret		int ret __always_unused
+
+#define ___wait_event(wq, condition, state, exclusive, ret, cmd)	\
+do {									\
+	__label__ __out;						\
+	DEFINE_WAIT(__wait);						\
+									\
+	for (;;) {							\
+		if (exclusive)						\
+			prepare_to_wait_exclusive(&wq, &__wait, state); \
+		else							\
+			prepare_to_wait(&wq, &__wait, state);		\
+									\
+		if (condition)						\
+			break;						\
+									\
+		if (___wait_signal_pending(state)) {			\
+			ret = -ERESTARTSYS;				\
+			if (exclusive) {				\
+				abort_exclusive_wait(&wq, &__wait, 	\
+						     state, NULL); 	\
+				goto __out;				\
+			}						\
+			break;						\
+		}							\
+									\
+		cmd;							\
+	}								\
+	finish_wait(&wq, &__wait);					\
+__out:	;								\
+} while (0)
+
 #define __wait_event(wq, condition) 					\
 do {									\
 	DEFINE_WAIT(__wait);						\
...	...	@@ -187,6 +187,42 @@
187	187	__cond \|\| !ret; \
188	188	})
189	189
	190	+#define ___wait_signal_pending(state) \
	191	+ ((state == TASK_INTERRUPTIBLE && signal_pending(current)) \|\| \
	192	+ (state == TASK_KILLABLE && fatal_signal_pending(current)))
	193	+
	194	+#define ___wait_nop_ret int ret __always_unused
	195	+
	196	+#define ___wait_event(wq, condition, state, exclusive, ret, cmd) \
	197	+do { \
	198	+ __label__ __out; \
	199	+ DEFINE_WAIT(__wait); \
	200	+ \
	201	+ for (;;) { \
	202	+ if (exclusive) \
	203	+ prepare_to_wait_exclusive(&wq, &__wait, state); \
	204	+ else \
	205	+ prepare_to_wait(&wq, &__wait, state); \
	206	+ \
	207	+ if (condition) \
	208	+ break; \
	209	+ \
	210	+ if (___wait_signal_pending(state)) { \
	211	+ ret = -ERESTARTSYS; \
	212	+ if (exclusive) { \
	213	+ abort_exclusive_wait(&wq, &__wait, \
	214	+ state, NULL); \
	215	+ goto __out; \
	216	+ } \
	217	+ break; \
	218	+ } \
	219	+ \
	220	+ cmd; \
	221	+ } \
	222	+ finish_wait(&wq, &__wait); \
	223	+__out: ; \
	224	+} while (0)
	225	+
190	226	#define __wait_event(wq, condition) \
191	227	do { \
192	228	DEFINE_WAIT(__wait); \