From 500410226f62928638b5ffb4a8ed292fafa46c95 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Sebastian=20Dr=C3=B6ge?= <sebastian.droege@collabora.co.uk>
Date: Thu, 20 Dec 2012 18:16:43 +0100
Subject: [PATCH] omxrecmutex: Fix yet another race condition that resulted in
 deadlocks

---
 omx/gstomxrecmutex.c | 19 ++++++-------------
 omx/gstomxrecmutex.h |  1 -
 2 files changed, 6 insertions(+), 14 deletions(-)

diff --git a/omx/gstomxrecmutex.c b/omx/gstomxrecmutex.c
index 6972bc2..a4e81a8 100644
--- a/omx/gstomxrecmutex.c
+++ b/omx/gstomxrecmutex.c
@@ -30,6 +30,7 @@ gst_omx_rec_mutex_init (GstOMXRecMutex * mutex)
   g_mutex_init (&mutex->lock);
   g_mutex_init (&mutex->recursion_lock);
   g_atomic_int_set (&mutex->recursion_allowed, FALSE);
+  g_atomic_int_set (&mutex->recursion_pending, FALSE);
 }
 
 void
@@ -56,6 +57,7 @@ gst_omx_rec_mutex_lock_for_recursion (GstOMXRecMutex * mutex)
 {
   gboolean exchanged;
 
+  g_mutex_lock (&mutex->recursion_lock);
   g_mutex_lock (&mutex->lock);
   exchanged =
       g_atomic_int_compare_and_exchange (&mutex->recursion_pending, FALSE,
@@ -72,8 +74,8 @@ gst_omx_rec_mutex_unlock_for_recursion (GstOMXRecMutex * mutex)
       g_atomic_int_compare_and_exchange (&mutex->recursion_pending, TRUE,
       FALSE);
   g_assert (exchanged);
-  g_cond_broadcast (&mutex->recursion_wait_cond);
   g_mutex_unlock (&mutex->lock);
+  g_mutex_unlock (&mutex->recursion_lock);
 }
 
 /* must be called with mutex->lock taken */
@@ -82,7 +84,6 @@ gst_omx_rec_mutex_begin_recursion (GstOMXRecMutex * mutex)
 {
   gboolean exchanged;
 
-  g_mutex_lock (&mutex->recursion_lock);
   exchanged =
       g_atomic_int_compare_and_exchange (&mutex->recursion_allowed, FALSE,
       TRUE);
@@ -91,7 +92,6 @@ gst_omx_rec_mutex_begin_recursion (GstOMXRecMutex * mutex)
       g_atomic_int_compare_and_exchange (&mutex->recursion_pending, TRUE,
       FALSE);
   g_assert (exchanged);
-  g_cond_broadcast (&mutex->recursion_wait_cond);
   g_mutex_unlock (&mutex->recursion_lock);
 }
 
@@ -110,7 +110,6 @@ gst_omx_rec_mutex_end_recursion (GstOMXRecMutex * mutex)
       g_atomic_int_compare_and_exchange (&mutex->recursion_pending, FALSE,
       TRUE);
   g_assert (exchanged);
-  g_mutex_unlock (&mutex->recursion_lock);
 }
 
 void
@@ -118,15 +117,9 @@ gst_omx_rec_mutex_recursive_lock (GstOMXRecMutex * mutex)
 {
   g_mutex_lock (&mutex->recursion_lock);
   if (!g_atomic_int_get (&mutex->recursion_allowed)) {
-    /* If recursion is pending wait until it happened */
-    while (g_atomic_int_get (&mutex->recursion_pending))
-      g_cond_wait (&mutex->recursion_wait_cond, &mutex->recursion_lock);
-
-    if (!g_atomic_int_get (&mutex->recursion_allowed)) {
-      /* no recursion allowed, lock the proper mutex */
-      g_mutex_lock (&mutex->lock);
-      g_mutex_unlock (&mutex->recursion_lock);
-    }
+    /* no recursion allowed, lock the proper mutex */
+    g_mutex_lock (&mutex->lock);
+    g_mutex_unlock (&mutex->recursion_lock);
   }
 }
 
diff --git a/omx/gstomxrecmutex.h b/omx/gstomxrecmutex.h
index 92aec39..2621239 100644
--- a/omx/gstomxrecmutex.h
+++ b/omx/gstomxrecmutex.h
@@ -97,7 +97,6 @@ struct _GstOMXRecMutex {
    * will be allowed soon
    */
   volatile gint recursion_pending;
-  GCond recursion_wait_cond;
 };
 
 void            gst_omx_rec_mutex_init (GstOMXRecMutex * mutex);
-- 
2.7.4