Presumably Peter's review comments for "restart_syscall: use freezable
blocking call" also apply here.

Please send your signed-off-by: for both patches, as detailed in
Documentation/SubmittingPatches section 11, thanks.


From: Yogesh Gaur <yn.g...@samsung.com>
Subject: ipc/msg.c: use freezable blocking call

Avoid waking up every thread sleeping in a msgrcv 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.

Ref: https://lkml.org/lkml/2013/5/1/424

Backtrace: 
[<c03e3924>] (__schedule+0x0/0x5d8) from [<c03e3f88>] (schedule+0x8c/0x90)
[<c03e3efc>] (schedule+0x0/0x90) from [<c01ef9f8>] (do_msgrcv+0x2e0/0x368)
[<c01ef718>] (do_msgrcv+0x0/0x368) from [<c01efaac>] (SyS_msgrcv+0x2c/0x38)
[<c01efa80>] (SyS_msgrcv+0x0/0x38) from [<c001a180>] (ret_fast_syscall+0x0/0x48)
tPlay0Cb2       R running      0   297    204 0x00000001

Signed-off-by: Yogesh Gaur <yn.g...@samsung.com>
Signed-off-by: Manjeet Pawar <manjee...@samsung.com>
Reviewed-by : Ajeet Yadav <ajee...@samsung.com>
Cc: Peter Zijlstra <a.p.zijls...@chello.nl>
Cc: Tejun Heo <t...@kernel.org>
Signed-off-by: Andrew Morton <a...@linux-foundation.org>
---

 ipc/msg.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff -puN ipc/msg.c~msgrcv-use-freezable-blocking-call ipc/msg.c
--- a/ipc/msg.c~msgrcv-use-freezable-blocking-call
+++ a/ipc/msg.c
@@ -37,6 +37,7 @@
 #include <linux/rwsem.h>
 #include <linux/nsproxy.h>
 #include <linux/ipc_namespace.h>
+#include <linux/freezer.h>
 
 #include <asm/current.h>
 #include <linux/uaccess.h>
@@ -915,7 +916,7 @@ long do_msgrcv(int msqid, void __user *b
 
                ipc_unlock_object(&msq->q_perm);
                rcu_read_unlock();
-               schedule();
+               freezable_schedule();
 
                /* Lockless receive, part 1:
                 * Disable preemption.  We don't hold a reference to the queue
_

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