Merge branch 'freezer'

* freezer:
  af_unix: use freezable blocking calls in read
  sigtimedwait: use freezable blocking call
  nanosleep: use freezable blocking call
  futex: use freezable blocking call
  select: use freezable blocking call
  epoll: use freezable blocking call
  binder: use freezable blocking calls
  freezer: add new freezable helpers using freezer_do_not_count()
  freezer: convert freezable helpers to static inline where possible
  freezer: convert freezable helpers to freezer_do_not_count()
  freezer: skip waking up tasks with PF_FREEZER_SKIP set
  freezer: shorten freezer sleep time using exponential backoff
  lockdep: check that no locks held at freeze time
  lockdep: remove task argument from debug_check_no_locks_held
  freezer: add unsafe versions of freezable helpers for CIFS
  freezer: add unsafe versions of freezable helpers for NFS

2 files changed, 142 insertions, 33 deletions

diff --git a/include/linux/debug_locks.h b/include/linux/debug_locks.h
index 21ca773f77bf..822c1354f3a6 100644
--- a/include/linux/debug_locks.h
+++ b/include/linux/debug_locks.h
@@ -51,7 +51,7 @@ struct task_struct;
 extern void debug_show_all_locks(void);
 extern void debug_show_held_locks(struct task_struct *task);
 extern void debug_check_no_locks_freed(const void *from, unsigned long len);
-extern void debug_check_no_locks_held(struct task_struct *task);
+extern void debug_check_no_locks_held(void);
 #else
 static inline void debug_show_all_locks(void)
 {
@@ -67,7 +67,7 @@ debug_check_no_locks_freed(const void *from, unsigned long len)
 }
 
 static inline void
-debug_check_no_locks_held(struct task_struct *task)
+debug_check_no_locks_held(void)
 {
 }
 #endif
diff --git a/include/linux/freezer.h b/include/linux/freezer.h
index e70df40d84f6..7fd81b8c4897 100644
--- a/include/linux/freezer.h
+++ b/include/linux/freezer.h
@@ -3,6 +3,7 @@
 #ifndef FREEZER_H_INCLUDED
 #define FREEZER_H_INCLUDED
 
+#include <linux/debug_locks.h>
 #include <linux/sched.h>
 #include <linux/wait.h>
 #include <linux/atomic.h>
@@ -46,7 +47,11 @@ extern int freeze_kernel_threads(void);
 extern void thaw_processes(void);
 extern void thaw_kernel_threads(void);
 
-static inline bool try_to_freeze(void)
+/*
+ * DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION
+ * If try_to_freeze causes a lockdep warning it means the caller may deadlock
+ */
+static inline bool try_to_freeze_unsafe(void)
 {
         might_sleep();
         if (likely(!freezing(current)))
@@ -54,6 +59,13 @@ static inline bool try_to_freeze(void)
         return __refrigerator(false);
 }
 
+static inline bool try_to_freeze(void)
+{
+        if (!(current->flags & PF_NOFREEZE))
+                debug_check_no_locks_held();
+        return try_to_freeze_unsafe();
+}
+
 extern bool freeze_task(struct task_struct *p);
 extern bool set_freezable(void);
 
@@ -115,6 +127,14 @@ static inline void freezer_count(void)
         try_to_freeze();
 }
 
+/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */
+static inline void freezer_count_unsafe(void)
+{
+        current->flags &= ~PF_FREEZER_SKIP;
+        smp_mb();
+        try_to_freeze_unsafe();
+}
+
 /**
  * freezer_should_skip - whether to skip a task when determining frozen
  *                       state is reached
@@ -139,28 +159,86 @@ static inline bool freezer_should_skip(struct task_struct *p)
 }
 
 /*
- * These macros are intended to be used whenever you want allow a sleeping
+ * These functions are intended to be used whenever you want allow a sleeping
  * task to be frozen. Note that neither return any clear indication of
  * whether a freeze event happened while in this function.
  */
 
 /* Like schedule(), but should not block the freezer. */
-#define freezable_schedule()                                            \
-({                                                                      \
-        freezer_do_not_count();                                         \
-        schedule();                                                     \
-        freezer_count();                                                \
-})
+static inline void freezable_schedule(void)
+{
+        freezer_do_not_count();
+        schedule();
+        freezer_count();
+}
+
+/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */
+static inline void freezable_schedule_unsafe(void)
+{
+        freezer_do_not_count();
+        schedule();
+        freezer_count_unsafe();
+}
+
+/*
+ * Like freezable_schedule_timeout(), but should not block the freezer.  Do not
+ * call this with locks held.
+ */
+static inline long freezable_schedule_timeout(long timeout)
+{
+        long __retval;
+        freezer_do_not_count();
+        __retval = schedule_timeout(timeout);
+        freezer_count();
+        return __retval;
+}
+
+/*
+ * Like schedule_timeout_interruptible(), but should not block the freezer.  Do not
+ * call this with locks held.
+ */
+static inline long freezable_schedule_timeout_interruptible(long timeout)
+{
+        long __retval;
+        freezer_do_not_count();
+        __retval = schedule_timeout_interruptible(timeout);
+        freezer_count();
+        return __retval;
+}
 
 /* Like schedule_timeout_killable(), but should not block the freezer. */
-#define freezable_schedule_timeout_killable(timeout)                    \
-({                                                                      \
-        long __retval;                                                  \
-        freezer_do_not_count();                                         \
-        __retval = schedule_timeout_killable(timeout);                  \
-        freezer_count();                                                \
-        __retval;                                                       \
-})
+static inline long freezable_schedule_timeout_killable(long timeout)
+{
+        long __retval;
+        freezer_do_not_count();
+        __retval = schedule_timeout_killable(timeout);
+        freezer_count();
+        return __retval;
+}
+
+/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */
+static inline long freezable_schedule_timeout_killable_unsafe(long timeout)
+{
+        long __retval;
+        freezer_do_not_count();
+        __retval = schedule_timeout_killable(timeout);
+        freezer_count_unsafe();
+        return __retval;
+}
+
+/*
+ * Like schedule_hrtimeout_range(), but should not block the freezer.  Do not
+ * call this with locks held.
+ */
+static inline int freezable_schedule_hrtimeout_range(ktime_t *expires,
+                unsigned long delta, const enum hrtimer_mode mode)
+{
+        int __retval;
+        freezer_do_not_count();
+        __retval = schedule_hrtimeout_range(expires, delta, mode);
+        freezer_count();
+        return __retval;
+}
 
 /*
  * Freezer-friendly wrappers around wait_event_interruptible(),
@@ -177,33 +255,45 @@ static inline bool freezer_should_skip(struct task_struct *p)
         __retval;                                                       \
 })
 
+/* DO NOT ADD ANY NEW CALLERS OF THIS FUNCTION */
+#define wait_event_freezekillable_unsafe(wq, condition)                 \
+({                                                                      \
+        int __retval;                                                   \
+        freezer_do_not_count();                                         \
+        __retval = wait_event_killable(wq, (condition));                \
+        freezer_count_unsafe();                                         \
+        __retval;                                                       \
+})
+
 #define wait_event_freezable(wq, condition)                             \
 ({                                                                      \
         int __retval;                                                   \
-        for (;;) {                                                      \
-                __retval = wait_event_interruptible(wq,                 \
-                                (condition) || freezing(current));      \
-                if (__retval || (condition))                            \
-                        break;                                          \
-                try_to_freeze();                                        \
-        }                                                               \
+        freezer_do_not_count();                                         \
+        __retval = wait_event_interruptible(wq, (condition));           \
+        freezer_count();                                                \
         __retval;                                                       \
 })
 
 #define wait_event_freezable_timeout(wq, condition, timeout)            \
 ({                                                                      \
         long __retval = timeout;                                        \
-        for (;;) {                                                      \
-                __retval = wait_event_interruptible_timeout(wq,         \
-                                (condition) || freezing(current),       \
-                                __retval);                              \
-                if (__retval <= 0 || (condition))                       \
-                        break;                                          \
-                try_to_freeze();                                        \
-        }                                                               \
+        freezer_do_not_count();                                         \
+        __retval = wait_event_interruptible_timeout(wq, (condition),    \
+                                __retval);                              \
+        freezer_count();                                                \
         __retval;                                                       \
 })
 
+#define wait_event_freezable_exclusive(wq, condition)                   \
+({                                                                      \
+        int __retval;                                                   \
+        freezer_do_not_count();                                         \
+        __retval = wait_event_interruptible_exclusive(wq, condition);   \
+        freezer_count();                                                \
+        __retval;                                                       \
+})
+
+
 #else /* !CONFIG_FREEZER */
 static inline bool frozen(struct task_struct *p) { return false; }
 static inline bool freezing(struct task_struct *p) { return false; }
@@ -225,18 +315,37 @@ static inline void set_freezable(void) {}
 
 #define freezable_schedule()  schedule()
 
+#define freezable_schedule_unsafe()  schedule()
+
+#define freezable_schedule_timeout(timeout)  schedule_timeout(timeout)
+
+#define freezable_schedule_timeout_interruptible(timeout)               \
+        schedule_timeout_interruptible(timeout)
+
 #define freezable_schedule_timeout_killable(timeout)                    \
         schedule_timeout_killable(timeout)
 
+#define freezable_schedule_timeout_killable_unsafe(timeout)             \
+        schedule_timeout_killable(timeout)
+
+#define freezable_schedule_hrtimeout_range(expires, delta, mode)        \
+        schedule_hrtimeout_range(expires, delta, mode)
+
 #define wait_event_freezable(wq, condition)                             \
                 wait_event_interruptible(wq, condition)
 
 #define wait_event_freezable_timeout(wq, condition, timeout)            \
                 wait_event_interruptible_timeout(wq, condition, timeout)
 
+#define wait_event_freezable_exclusive(wq, condition)                   \
+                wait_event_interruptible_exclusive(wq, condition)
+
 #define wait_event_freezekillable(wq, condition)                \
                 wait_event_killable(wq, condition)
 
+#define wait_event_freezekillable_unsafe(wq, condition)                 \
+                wait_event_killable(wq, condition)
+
 #endif /* !CONFIG_FREEZER */
 
 #endif  /* FREEZER_H_INCLUDED */