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-rw-r--r--include/linux/swait.h36
1 files changed, 18 insertions, 18 deletions
diff --git a/include/linux/swait.h b/include/linux/swait.h
index bf8cb0dee23c..73e06e9986d4 100644
--- a/include/linux/swait.h
+++ b/include/linux/swait.h
@@ -16,7 +16,7 @@
* wait-queues, but the semantics are actually completely different, and
* every single user we have ever had has been buggy (or pointless).
*
- * A "swake_up()" only wakes up _one_ waiter, which is not at all what
+ * A "swake_up_one()" only wakes up _one_ waiter, which is not at all what
* "wake_up()" does, and has led to problems. In other cases, it has
* been fine, because there's only ever one waiter (kvm), but in that
* case gthe whole "simple" wait-queue is just pointless to begin with,
@@ -38,8 +38,8 @@
* all wakeups are TASK_NORMAL in order to avoid O(n) lookups for the right
* sleeper state.
*
- * - the exclusive mode; because this requires preserving the list order
- * and this is hard.
+ * - the !exclusive mode; because that leads to O(n) wakeups, everything is
+ * exclusive.
*
* - custom wake callback functions; because you cannot give any guarantees
* about random code. This also allows swait to be used in RT, such that
@@ -115,7 +115,7 @@ extern void __init_swait_queue_head(struct swait_queue_head *q, const char *name
* CPU0 - waker CPU1 - waiter
*
* for (;;) {
- * @cond = true; prepare_to_swait(&wq_head, &wait, state);
+ * @cond = true; prepare_to_swait_exclusive(&wq_head, &wait, state);
* smp_mb(); // smp_mb() from set_current_state()
* if (swait_active(wq_head)) if (@cond)
* wake_up(wq_head); break;
@@ -157,20 +157,20 @@ static inline bool swq_has_sleeper(struct swait_queue_head *wq)
return swait_active(wq);
}
-extern void swake_up(struct swait_queue_head *q);
+extern void swake_up_one(struct swait_queue_head *q);
extern void swake_up_all(struct swait_queue_head *q);
extern void swake_up_locked(struct swait_queue_head *q);
-extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
-extern void prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait, int state);
+extern void prepare_to_swait_exclusive(struct swait_queue_head *q, struct swait_queue *wait, int state);
extern long prepare_to_swait_event(struct swait_queue_head *q, struct swait_queue *wait, int state);
extern void __finish_swait(struct swait_queue_head *q, struct swait_queue *wait);
extern void finish_swait(struct swait_queue_head *q, struct swait_queue *wait);
-/* as per ___wait_event() but for swait, therefore "exclusive == 0" */
+/* as per ___wait_event() but for swait, therefore "exclusive == 1" */
#define ___swait_event(wq, condition, state, ret, cmd) \
({ \
+ __label__ __out; \
struct swait_queue __wait; \
long __ret = ret; \
\
@@ -183,20 +183,20 @@ extern void finish_swait(struct swait_queue_head *q, struct swait_queue *wait);
\
if (___wait_is_interruptible(state) && __int) { \
__ret = __int; \
- break; \
+ goto __out; \
} \
\
cmd; \
} \
finish_swait(&wq, &__wait); \
- __ret; \
+__out: __ret; \
})
#define __swait_event(wq, condition) \
(void)___swait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, \
schedule())
-#define swait_event(wq, condition) \
+#define swait_event_exclusive(wq, condition) \
do { \
if (condition) \
break; \
@@ -208,7 +208,7 @@ do { \
TASK_UNINTERRUPTIBLE, timeout, \
__ret = schedule_timeout(__ret))
-#define swait_event_timeout(wq, condition, timeout) \
+#define swait_event_timeout_exclusive(wq, condition, timeout) \
({ \
long __ret = timeout; \
if (!___wait_cond_timeout(condition)) \
@@ -220,7 +220,7 @@ do { \
___swait_event(wq, condition, TASK_INTERRUPTIBLE, 0, \
schedule())
-#define swait_event_interruptible(wq, condition) \
+#define swait_event_interruptible_exclusive(wq, condition) \
({ \
int __ret = 0; \
if (!(condition)) \
@@ -233,7 +233,7 @@ do { \
TASK_INTERRUPTIBLE, timeout, \
__ret = schedule_timeout(__ret))
-#define swait_event_interruptible_timeout(wq, condition, timeout) \
+#define swait_event_interruptible_timeout_exclusive(wq, condition, timeout)\
({ \
long __ret = timeout; \
if (!___wait_cond_timeout(condition)) \
@@ -246,7 +246,7 @@ do { \
(void)___swait_event(wq, condition, TASK_IDLE, 0, schedule())
/**
- * swait_event_idle - wait without system load contribution
+ * swait_event_idle_exclusive - wait without system load contribution
* @wq: the waitqueue to wait on
* @condition: a C expression for the event to wait for
*
@@ -257,7 +257,7 @@ do { \
* condition and doesn't want to contribute to system load. Signals are
* ignored.
*/
-#define swait_event_idle(wq, condition) \
+#define swait_event_idle_exclusive(wq, condition) \
do { \
if (condition) \
break; \
@@ -270,7 +270,7 @@ do { \
__ret = schedule_timeout(__ret))
/**
- * swait_event_idle_timeout - wait up to timeout without load contribution
+ * swait_event_idle_timeout_exclusive - wait up to timeout without load contribution
* @wq: the waitqueue to wait on
* @condition: a C expression for the event to wait for
* @timeout: timeout at which we'll give up in jiffies
@@ -288,7 +288,7 @@ do { \
* or the remaining jiffies (at least 1) if the @condition evaluated
* to %true before the @timeout elapsed.
*/
-#define swait_event_idle_timeout(wq, condition, timeout) \
+#define swait_event_idle_timeout_exclusive(wq, condition, timeout) \
({ \
long __ret = timeout; \
if (!___wait_cond_timeout(condition)) \