[PATCH 3/5] logger: reorder prepare_to_wait and mutex_lock

[Tim Bird <tim.bird@am.sony.com>]

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>
---
 drivers/staging/android/logger.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/staging/android/logger.c b/drivers/staging/android/logger.c
index 92cfd94..54b7cdf 100644
--- 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)
-- 
1.7.2.3