sched/wait: Add might_sleep() checks

Add more might_sleep() checks, suppose someone put a wait_event() like
thing in a wait loop..

Can't put might_sleep() in ___wait_event() because there's the locked
primitives which call ___wait_event() with locks held.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: tglx@linutronix.de
Cc: ilya.dryomov@inktank.com
Cc: umgwanakikbuti@gmail.com
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140924082242.119255706@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/include/linux/wait.h b/include/linux/wait.h
index fc0e99395fbb..0421775e0b9f 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -261,6 +261,7 @@ __out:	__ret;								\
  */
 #define wait_event(wq, condition)                                       \
 do {                                                                    \
+        might_sleep();                                                  \
         if (condition)                                                  \
                 break;                                                  \
         __wait_event(wq, condition);                                    \
@@ -293,6 +294,7 @@ do {									\
 #define wait_event_timeout(wq, condition, timeout)                      \
 ({                                                                      \
         long __ret = timeout;                                           \
+        might_sleep();                                                  \
         if (!___wait_cond_timeout(condition))                           \
                 __ret = __wait_event_timeout(wq, condition, timeout);   \
         __ret;                                                          \
@@ -318,6 +320,7 @@ do {									\
  */
 #define wait_event_cmd(wq, condition, cmd1, cmd2)                       \
 do {                                                                    \
+        might_sleep();                                                  \
         if (condition)                                                  \
                 break;                                                  \
         __wait_event_cmd(wq, condition, cmd1, cmd2);                    \
@@ -345,6 +348,7 @@ do {									\
 #define wait_event_interruptible(wq, condition)                         \
 ({                                                                      \
         int __ret = 0;                                                  \
+        might_sleep();                                                  \
         if (!(condition))                                               \
                 __ret = __wait_event_interruptible(wq, condition);      \
         __ret;                                                          \
@@ -378,6 +382,7 @@ do {									\
 #define wait_event_interruptible_timeout(wq, condition, timeout)        \
 ({                                                                      \
         long __ret = timeout;                                           \
+        might_sleep();                                                  \
         if (!___wait_cond_timeout(condition))                           \
                 __ret = __wait_event_interruptible_timeout(wq,          \
                                                 condition, timeout);    \
@@ -428,6 +433,7 @@ do {									\
 #define wait_event_hrtimeout(wq, condition, timeout)                    \
 ({                                                                      \
         int __ret = 0;                                                  \
+        might_sleep();                                                  \
         if (!(condition))                                               \
                 __ret = __wait_event_hrtimeout(wq, condition, timeout,  \
                                                TASK_UNINTERRUPTIBLE);   \
@@ -453,6 +459,7 @@ do {									\
 #define wait_event_interruptible_hrtimeout(wq, condition, timeout)      \
 ({                                                                      \
         long __ret = 0;                                                 \
+        might_sleep();                                                  \
         if (!(condition))                                               \
                 __ret = __wait_event_hrtimeout(wq, condition, timeout,  \
                                                TASK_INTERRUPTIBLE);     \
@@ -466,6 +473,7 @@ do {									\
 #define wait_event_interruptible_exclusive(wq, condition)               \
 ({                                                                      \
         int __ret = 0;                                                  \
+        might_sleep();                                                  \
         if (!(condition))                                               \
                 __ret = __wait_event_interruptible_exclusive(wq, condition);\
         __ret;                                                          \
@@ -640,6 +648,7 @@ do {									\
 #define wait_event_killable(wq, condition)                              \
 ({                                                                      \
         int __ret = 0;                                                  \
+        might_sleep();                                                  \
         if (!(condition))                                               \
                 __ret = __wait_event_killable(wq, condition);           \
         __ret;                                                          \
@@ -891,6 +900,7 @@ extern int bit_wait_io_timeout(struct wait_bit_key *);
 static inline int
 wait_on_bit(void *word, int bit, unsigned mode)
 {
+        might_sleep();
         if (!test_bit(bit, word))
                 return 0;
         return out_of_line_wait_on_bit(word, bit,
@@ -915,6 +925,7 @@ wait_on_bit(void *word, int bit, unsigned mode)
 static inline int
 wait_on_bit_io(void *word, int bit, unsigned mode)
 {
+        might_sleep();
         if (!test_bit(bit, word))
                 return 0;
         return out_of_line_wait_on_bit(word, bit,
@@ -941,6 +952,7 @@ wait_on_bit_io(void *word, int bit, unsigned mode)
 static inline int
 wait_on_bit_action(void *word, int bit, wait_bit_action_f *action, unsigned mode)
 {
+        might_sleep();
         if (!test_bit(bit, word))
                 return 0;
         return out_of_line_wait_on_bit(word, bit, action, mode);
@@ -968,6 +980,7 @@ wait_on_bit_action(void *word, int bit, wait_bit_action_f *action, unsigned mode
 static inline int
 wait_on_bit_lock(void *word, int bit, unsigned mode)
 {
+        might_sleep();
         if (!test_and_set_bit(bit, word))
                 return 0;
         return out_of_line_wait_on_bit_lock(word, bit, bit_wait, mode);
@@ -991,6 +1004,7 @@ wait_on_bit_lock(void *word, int bit, unsigned mode)
 static inline int
 wait_on_bit_lock_io(void *word, int bit, unsigned mode)
 {
+        might_sleep();
         if (!test_and_set_bit(bit, word))
                 return 0;
         return out_of_line_wait_on_bit_lock(word, bit, bit_wait_io, mode);
@@ -1016,6 +1030,7 @@ wait_on_bit_lock_io(void *word, int bit, unsigned mode)
 static inline int
 wait_on_bit_lock_action(void *word, int bit, wait_bit_action_f *action, unsigned mode)
 {
+        might_sleep();
         if (!test_and_set_bit(bit, word))
                 return 0;
         return out_of_line_wait_on_bit_lock(word, bit, action, mode);
@@ -1034,6 +1049,7 @@ wait_on_bit_lock_action(void *word, int bit, wait_bit_action_f *action, unsigned
 static inline
 int wait_on_atomic_t(atomic_t *val, int (*action)(atomic_t *), unsigned mode)
 {
+        might_sleep();
         if (atomic_read(val) == 0)
                 return 0;
         return out_of_line_wait_on_atomic_t(val, action, mode);