Merge branch 'for-3.20/drivers' of git://git.kernel.dk/linux-block

[linux-drm-fsl-dcu.git] / include / linux / wait.h

diff --git a/include/linux/wait.h b/include/linux/wait.h
index 71fc1d31e48df339feb1ff1911aa9c4aa9c8e351..2db83349865bb7a27eba8438a9e8a3cd8509abd0 100644 (file)
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -378,7 +378,6 @@ do {                                                                        \
  */
 #define wait_event_cmd(wq, condition, cmd1, cmd2)                      \
 do {                                                                   \
-       might_sleep();                                                  \
        if (condition)                                                  \
                break;                                                  \
        __wait_event_cmd(wq, condition, cmd1, cmd2);                    \
@@ -1005,6 +1004,32 @@ wait_on_bit_io(void *word, int bit, unsigned mode)
                                       mode);
 }
 
+/**
+ * wait_on_bit_timeout - wait for a bit to be cleared or a timeout elapses
+ * @word: the word being waited on, a kernel virtual address
+ * @bit: the bit of the word being waited on
+ * @mode: the task state to sleep in
+ * @timeout: timeout, in jiffies
+ *
+ * Use the standard hashed waitqueue table to wait for a bit
+ * to be cleared. This is similar to wait_on_bit(), except also takes a
+ * timeout parameter.
+ *
+ * Returned value will be zero if the bit was cleared before the
+ * @timeout elapsed, or non-zero if the @timeout elapsed or process
+ * received a signal and the mode permitted wakeup on that signal.
+ */
+static inline int
+wait_on_bit_timeout(void *word, int bit, unsigned mode, unsigned long timeout)
+{
+       might_sleep();
+       if (!test_bit(bit, word))
+               return 0;
+       return out_of_line_wait_on_bit_timeout(word, bit,
+                                              bit_wait_timeout,
+                                              mode, timeout);
+}
+
 /**
  * wait_on_bit_action - wait for a bit to be cleared
  * @word: the word being waited on, a kernel virtual address