commit 4e620ddce344e946ced992f61a69c367ff92fe24
author Mathias Agopian <mathias@google.com> Thu May 30 16:07:36 2013 -0700
committer Mathias Agopian <mathias@google.com> Thu May 30 16:07:36 2013 -0700
tree e54399a961f03e961411366deee168a3f9bd6e31
parent 9e3cb55b8f6f007906872decfe3b8a2541e94dd2

free EGL resources associated to a thread when it terminates

destroyed but current-to-a-thread resources are only destroyed
when they're made not-current; however, we were not destroying
those when the thread itself terminated, causing these resources
to be leaked forever.

we now install a tls-key destructor that takes care of this
by calling eglReleaseThread upon thread termination.

Bug: 9209776
Change-Id: I88298a34e3a27488eb81eab76717715569c7d57c

opengl/libs/EGL/egl_tls.cpp

diff --git a/opengl/libs/EGL/egl_tls.cpp b/opengl/libs/EGL/egl_tls.cpp
index 52312a2..f3739aa 100644
--- a/opengl/libs/EGL/egl_tls.cpp
+++ b/opengl/libs/EGL/egl_tls.cpp
@@ -29,8 +29,8 @@
 
 namespace android {
 
-pthread_key_t egl_tls_t::sKey = -1;
-pthread_mutex_t egl_tls_t::sLockKey = PTHREAD_MUTEX_INITIALIZER;
+pthread_key_t egl_tls_t::sKey = TLS_KEY_NOT_INITIALIZED;
+pthread_once_t egl_tls_t::sOnceKey = PTHREAD_ONCE_INIT;
 
 egl_tls_t::egl_tls_t()
     : error(EGL_SUCCESS), ctx(0), logCallWithNoContext(EGL_TRUE) {
@@ -59,12 +59,12 @@
 
 void egl_tls_t::validateTLSKey()
 {
-    if (sKey == -1) {
-        pthread_mutex_lock(&sLockKey);
-        if (sKey == -1)
-            pthread_key_create(&sKey, NULL);
-        pthread_mutex_unlock(&sLockKey);
-    }
+    struct TlsKeyInitializer {
+        static void create() {
+            pthread_key_create(&sKey, (void (*)(void*))&eglReleaseThread);
+        }
+    };
+    pthread_once(&sOnceKey, TlsKeyInitializer::create);
 }
 
 void egl_tls_t::setErrorEtcImpl(
@@ -104,11 +104,11 @@
 }
 
 void egl_tls_t::clearTLS() {
-    if (sKey != -1) {
+    if (sKey != TLS_KEY_NOT_INITIALIZED) {
         egl_tls_t* tls = (egl_tls_t*)pthread_getspecific(sKey);
         if (tls) {
-            delete tls;
             pthread_setspecific(sKey, 0);
+            delete tls;
         }
     }
 }
@@ -120,10 +120,13 @@
 }
 
 EGLint egl_tls_t::getError() {
-    if (sKey == -1)
+    if (sKey == TLS_KEY_NOT_INITIALIZED) {
         return EGL_SUCCESS;
+    }
     egl_tls_t* tls = (egl_tls_t*)pthread_getspecific(sKey);
-    if (!tls) return EGL_SUCCESS;
+    if (!tls) {
+        return EGL_SUCCESS;
+    }
     EGLint error = tls->error;
     tls->error = EGL_SUCCESS;
     return error;
@@ -135,8 +138,9 @@
 }
 
 EGLContext egl_tls_t::getContext() {
-    if (sKey == -1)
+    if (sKey == TLS_KEY_NOT_INITIALIZED) {
         return EGL_NO_CONTEXT;
+    }
     egl_tls_t* tls = (egl_tls_t *)pthread_getspecific(sKey);
     if (!tls) return EGL_NO_CONTEXT;
     return tls->ctx;