[PATCH 1/2] wait: turn "bool exclusive" arg of __wait_event() into wflags

From: Oleg Nesterov
Date: Thu Mar 20 2014 - 13:52:38 EST


Change ___wait_event() to accept __wait.flags as an argument instead
of "exclusive", and change the only caller which uses exclusive == 1.

This allows us to add another WQ_FLAG (see the next patch). And this
is more flexible, we can overload this argument to pass more info.

This should not affect the generated code, currently this argument is
always __builtin_constant_p().

Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx>
---
include/linux/wait.h | 16 ++++++++--------
1 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/include/linux/wait.h b/include/linux/wait.h
index 559044c..e547c6c 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -16,6 +16,7 @@ int default_wake_function(wait_queue_t *wait, unsigned mode, int flags, void *ke
struct __wait_queue {
unsigned int flags;
#define WQ_FLAG_EXCLUSIVE 0x01
+#define WQ_FLAG_MASK WQ_FLAG_EXCLUSIVE
void *private;
wait_queue_func_t func;
struct list_head task_list;
@@ -191,17 +192,16 @@ wait_queue_head_t *bit_waitqueue(void *, int);
(!__builtin_constant_p(state) || \
state == TASK_INTERRUPTIBLE || state == TASK_KILLABLE) \

-#define ___wait_event(wq, condition, state, exclusive, ret, cmd) \
+#define ___wait_event(wq, condition, state, wflags, ret, cmd) \
({ \
__label__ __out; \
wait_queue_t __wait; \
long __ret = ret; \
\
INIT_LIST_HEAD(&__wait.task_list); \
- if (exclusive) \
- __wait.flags = WQ_FLAG_EXCLUSIVE; \
- else \
- __wait.flags = 0; \
+ BUILD_BUG_ON(__builtin_constant_p(wflags) && \
+ ((wflags) & ~WQ_FLAG_MASK)); \
+ __wait.flags = wflags; \
\
for (;;) { \
long __int = prepare_to_wait_event(&wq, &__wait, state);\
@@ -211,7 +211,7 @@ wait_queue_head_t *bit_waitqueue(void *, int);
\
if (___wait_is_interruptible(state) && __int) { \
__ret = __int; \
- if (exclusive) { \
+ if ((wflags) & WQ_FLAG_EXCLUSIVE) { \
abort_exclusive_wait(&wq, &__wait, \
state, NULL); \
goto __out; \
@@ -438,8 +438,8 @@ do { \
})

#define __wait_event_interruptible_exclusive(wq, condition) \
- ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \
- schedule())
+ ___wait_event(wq, condition, TASK_INTERRUPTIBLE, \
+ WQ_FLAG_EXCLUSIVE, 0, schedule())

#define wait_event_interruptible_exclusive(wq, condition) \
({ \
--
1.5.5.1


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/