[PATCH v3 12/16] select: use freezable blocking call

[Colin Cross <ccross@android.com>]

Avoid waking up every thread sleeping in a select 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 <tj@kernel.org>
Signed-off-by: Colin Cross <ccross@android.com>
---
 fs/select.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/select.c b/fs/select.c
index 8c1c96c..6b14dc7 100644
--- a/fs/select.c
+++ b/fs/select.c
@@ -27,6 +27,7 @@
 #include <linux/rcupdate.h>
 #include <linux/hrtimer.h>
 #include <linux/sched/rt.h>
+#include <linux/freezer.h>
 
 #include <asm/uaccess.h>
 
@@ -236,7 +237,8 @@ int poll_schedule_timeout(struct poll_wqueues *pwq, int state,
 
 	set_current_state(state);
 	if (!pwq->triggered)
-		rc = schedule_hrtimeout_range(expires, slack, HRTIMER_MODE_ABS);
+		rc = freezable_schedule_hrtimeout_range(expires, slack,
+							HRTIMER_MODE_ABS);
 	__set_current_state(TASK_RUNNING);
 
 	/*
-- 
1.8.2.1