From c76c7ca31f16c9556cad527bfa3504b0aafb3045 Mon Sep 17 00:00:00 2001
From: Tim Bird <tim.bird@am.sony.com>
Date: Tue, 7 Feb 2012 18:30:09 -0800
Subject: [PATCH] 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>
---
 drivers/staging/android/logger.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/android/logger.c b/drivers/staging/android/logger.c
index 1e9e638cfd7a..6dd6f0490c3a 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)