sched/wait: Remove might_sleep() from wait_event_cmd()

The patch e22b886a8a43 ("sched/wait: Add might_sleep() checks")
introduced a bug in the raid5 subsystem.

The function raid5_quiesce() (and resize_stripes()) uses the 'cmd'
part to release and acquire a spinlock (so we call the sleep
primitives in atomic context), and therefore we cannot do the
might_sleep() check.

Remove it.

Fixes: e22b886a8a43 ("sched/wait: Add might_sleep() checks")
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.LRH.2.02.1502020935580.13510@file01.intranet.prod.int.rdu2.redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/include/linux/wait.h b/include/linux/wait.h
index 2232ed1..37423e0 100644 (file)
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -363,7 +363,6 @@ do {                                                                        \
  */
 #define wait_event_cmd(wq, condition, cmd1, cmd2)                      \
 do {                                                                   \
-       might_sleep();                                                  \
        if (condition)                                                  \
                break;                                                  \
        __wait_event_cmd(wq, condition, cmd1, cmd2);                    \