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authorDavidlohr Bueso <dave@stgolabs.net>2023-05-23 10:09:24 -0700
committerDan Williams <dan.j.williams@intel.com>2023-05-23 12:55:12 -0700
commitf6239d3f8ce4ebc5a5cfa3657377bd5007ae1547 (patch)
tree03e1470806884ec0756d6a09c0a5c0d6eaee0583
parenta70fc4ed20a6118837b0aecbbf789074935f473b (diff)
rcuwait: Support timeouts
The rcuwait utility provides an efficient and safe single wait/wake mechanism. It is used in situations where queued wait is the wrong semantics, and often too bulky. For example, cases where the wait is already done under a lock. In the past, rcuwait has been extended to support beyond only uninterruptible sleep, and similarly, there are users that can benefit for the addition of timeouts. As such, tntroduce rcuwait_wait_event_timeout(), with semantics equivalent to calls for queued wait counterparts. Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Link: https://lore.kernel.org/r/20230523170927.20685-2-dave@stgolabs.net Signed-off-by: Dan Williams <dan.j.williams@intel.com>
-rw-r--r--include/linux/rcuwait.h23
1 files changed, 20 insertions, 3 deletions
diff --git a/include/linux/rcuwait.h b/include/linux/rcuwait.h
index 8052d34da782..27343424225c 100644
--- a/include/linux/rcuwait.h
+++ b/include/linux/rcuwait.h
@@ -49,9 +49,9 @@ static inline void prepare_to_rcuwait(struct rcuwait *w)
extern void finish_rcuwait(struct rcuwait *w);
-#define rcuwait_wait_event(w, condition, state) \
+#define ___rcuwait_wait_event(w, condition, state, ret, cmd) \
({ \
- int __ret = 0; \
+ long __ret = ret; \
prepare_to_rcuwait(w); \
for (;;) { \
/* \
@@ -67,10 +67,27 @@ extern void finish_rcuwait(struct rcuwait *w);
break; \
} \
\
- schedule(); \
+ cmd; \
} \
finish_rcuwait(w); \
__ret; \
})
+#define rcuwait_wait_event(w, condition, state) \
+ ___rcuwait_wait_event(w, condition, state, 0, schedule())
+
+#define __rcuwait_wait_event_timeout(w, condition, state, timeout) \
+ ___rcuwait_wait_event(w, ___wait_cond_timeout(condition), \
+ state, timeout, \
+ __ret = schedule_timeout(__ret))
+
+#define rcuwait_wait_event_timeout(w, condition, state, timeout) \
+({ \
+ long __ret = timeout; \
+ if (!___wait_cond_timeout(condition)) \
+ __ret = __rcuwait_wait_event_timeout(w, condition, \
+ state, timeout); \
+ __ret; \
+})
+
#endif /* _LINUX_RCUWAIT_H_ */