staging: android: logger: reorder prepare_to_wait and mutex_lock

If mutex_lock waits, it will return in state TASK_RUNNING,
rubbing out the effect of prepare_to_wait().

Signed-off-by: Tim Bird <tim.bird@am.sony.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/android/logger.c b/drivers/staging/android/logger.c
index 1e9e638cfd7a92033d79d5529b8e418357c3885b..6dd6f0490c3ae299e847c7c638c037e17308ad8e 100644 (file)
--- a/drivers/staging/android/logger.c
+++ b/drivers/staging/android/logger.c
@@ -172,9 +172,10 @@ static ssize_t logger_read(struct file *file, char __user *buf,
 
 start:
        while (1) {
+               mutex_lock(&log->mutex);
+
                prepare_to_wait(&log->wq, &wait, TASK_INTERRUPTIBLE);
 
-               mutex_lock(&log->mutex);
                ret = (log->w_off == reader->r_off);
                mutex_unlock(&log->mutex);
                if (!ret)