Fix for Skia data race. This may introduce some performance issues; will watch perf bots carefully.

BUG=46672
TEST=see perf bits

Review URL: http://codereview.chromium.org/2876001

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@50510 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 9 insertions, 5 deletions

diff --git a/skia/ext/SkMemory_new_handler.cpp b/skia/ext/SkMemory_new_handler.cpp
index e64de61..06bc2c9 100644
--- a/skia/ext/SkMemory_new_handler.cpp
+++ b/skia/ext/SkMemory_new_handler.cpp
@@ -7,12 +7,15 @@
 #include <new>
 
 #include "third_party/skia/include/core/SkTypes.h"
+#include "third_party/skia/include/core/SkThread.h"
 
 // This implementation of sk_malloc_flags() and friends is identical
 // to SkMemory_malloc.c, except that it disables the CRT's new_handler
 // during malloc(), when SK_MALLOC_THROW is not set (ie., when
 // sk_malloc_flags() would not abort on NULL).
 
+static SkMutex gSkNewHandlerMutex;
+
 void sk_throw() {
     SkASSERT(!"sk_throw");
     abort();
@@ -45,13 +48,14 @@ void sk_free(void* p) {
 }
 
 void* sk_malloc_flags(size_t size, unsigned flags) {
-    std::new_handler old_handler;
-    if (!(flags & SK_MALLOC_THROW)) {
-      old_handler = std::set_new_handler(NULL);
-    }
-    void* p = malloc(size);
+    void* p;
     if (!(flags & SK_MALLOC_THROW)) {
+      SkAutoMutexAcquire lock(gSkNewHandlerMutex);
+      std::new_handler old_handler = std::set_new_handler(NULL);
+      p = malloc(size);
       std::set_new_handler(old_handler);
+    } else {
+      p = malloc(size);
     }
     if (p == NULL) {
         if (flags & SK_MALLOC_THROW) {