[v3,14/16] nanosleep: use freezable blocking call

Commit Message

Colin Cross May 6, 2013, 11:50 p.m. UTC

Avoid waking up every thread sleeping in a nanosleep call during
suspend and resume by calling a freezable blocking call.  Previous
patches modified the freezer to avoid sending wakeups to threads
that are blocked in freezable blocking calls.

This call was selected to be converted to a freezable call because
it doesn't hold any locks or release any resources when interrupted
that might be needed by another freezing task or a kernel driver
during suspend, and is a common site where idle userspace tasks are
blocked.

Acked-by: Tejun Heo <[e-mail]>
Acked-by: Thomas Gleixner <[e-mail]>
Signed-off-by: Colin Cross <[e-mail]>
---
 kernel/hrtimer.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Patch

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 14be27f..e036276 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -47,6 +47,7 @@ 
 #include <linux/sched/sysctl.h>
 #include <linux/sched/rt.h>
 #include <linux/timer.h>
+#include <linux/freezer.h>
 
 #include <asm/uaccess.h>
 
@@ -1525,7 +1526,7 @@  static int __sched do_nanosleep(struct hrtimer_sleeper *t, enum hrtimer_mode mod
 			t->task = NULL;
 
 		if (likely(t->task))
-			schedule();
+			freezable_schedule();
 
 		hrtimer_cancel(&t->timer);
 		mode = HRTIMER_MODE_ABS;