| /* | |
| * Copyright 2015 Google Inc. | |
| * | |
| * Use of this source code is governed by a BSD-style license that can be | |
| * found in the LICENSE file. | |
| */ | |
| #include "SkSpinlock.h" | |
| #if SK_CPU_SSE_LEVEL >= SK_CPU_SSE_LEVEL_SSE2 | |
| #include <emmintrin.h> | |
| static void pause() { _mm_pause(); } | |
| #else | |
| static void pause() { /*spin*/ } | |
| #endif | |
| void SkSpinlock::contendedAcquire() { | |
| // To act as a mutex, we need an acquire barrier when we acquire the lock. | |
| while (fLocked.exchange(true, std::memory_order_acquire)) { | |
| pause(); | |
| } | |
| } |