[PATCH 2/3] sched/wait: introduce wait_event_freezable_hrtimeout

From: Hugo Lefeuvre
Date: Fri Feb 01 2019 - 00:38:41 EST


introduce wait_event_freezable_hrtimeout, an interruptible and freezable
version of wait_event_hrtimeout.

Among others this helper will allow for simplifications in
staging/android/vsoc.c.

Signed-off-by: Hugo Lefeuvre <hle@xxxxxxxxxx>
---
include/linux/wait.h | 25 +++++++++++++++++++++----
1 file changed, 21 insertions(+), 4 deletions(-)

diff --git a/include/linux/wait.h b/include/linux/wait.h
index 5f3efabc36f4..c4cf5113f58a 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -483,7 +483,7 @@ do { \
__ret; \
})

-#define __wait_event_hrtimeout(wq_head, condition, timeout, state) \
+#define __wait_event_hrtimeout(wq_head, condition, timeout, state, cmd) \
({ \
int __ret = 0; \
struct hrtimer_sleeper __t; \
@@ -500,7 +500,7 @@ do { \
__ret = -ETIME; \
break; \
} \
- schedule()); \
+ cmd); \
\
hrtimer_cancel(&__t.timer); \
destroy_hrtimer_on_stack(&__t.timer); \
@@ -529,7 +529,23 @@ do { \
might_sleep(); \
if (!(condition)) \
__ret = __wait_event_hrtimeout(wq_head, condition, timeout, \
- TASK_UNINTERRUPTIBLE); \
+ TASK_UNINTERRUPTIBLE, \
+ schedule()); \
+ __ret; \
+})
+
+/*
+ * like wait_event_hrtimeout() -- except it uses TASK_INTERRUPTIBLE to avoid
+ * increasing load and is freezable.
+ */
+#define wait_event_freezable_hrtimeout(wq_head, condition, timeout) \
+({ \
+ int __ret = 0; \
+ might_sleep(); \
+ if (!(condition)) \
+ __ret = __wait_event_hrtimeout(wq_head, condition, timeout, \
+ TASK_INTERRUPTIBLE, \
+ freezable_schedule()); \
__ret; \
})

@@ -555,7 +571,8 @@ do { \
might_sleep(); \
if (!(condition)) \
__ret = __wait_event_hrtimeout(wq, condition, timeout, \
- TASK_INTERRUPTIBLE); \
+ TASK_INTERRUPTIBLE, \
+ schedule()); \
__ret; \
})

--
2.20.1