1 /* 2 * Copyright 2014 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "SkAtomics.h" 9 #include "SkEventTracer.h" 10 #include "SkOncePtr.h" 11 12 #include <stdlib.h> 13 14 class SkDefaultEventTracer : public SkEventTracer { 15 SkEventTracer::Handle 16 addTraceEvent(char phase, 17 const uint8_t* categoryEnabledFlag, 18 const char* name, 19 uint64_t id, 20 int numArgs, 21 const char** argNames, 22 const uint8_t* argTypes, 23 const uint64_t* argValues, 24 uint8_t flags) override { return 0; } 25 26 void 27 updateTraceEventDuration(const uint8_t* categoryEnabledFlag, 28 const char* name, 29 SkEventTracer::Handle handle) override {} 30 31 const uint8_t* getCategoryGroupEnabled(const char* name) override { 32 static uint8_t no = 0; 33 return &no; 34 } 35 const char* getCategoryGroupName( 36 const uint8_t* categoryEnabledFlag) override { 37 static const char* dummy = "dummy"; 38 return dummy; 39 } 40 }; 41 42 // We prefer gUserTracer if it's been set, otherwise we fall back on gDefaultTracer. 43 static SkEventTracer* gUserTracer = nullptr; 44 SK_DECLARE_STATIC_ONCE_PTR(SkDefaultEventTracer, gDefaultTracer); 45 46 void SkEventTracer::SetInstance(SkEventTracer* tracer) { 47 SkASSERT(nullptr == sk_atomic_load(&gUserTracer, sk_memory_order_acquire)); 48 sk_atomic_store(&gUserTracer, tracer, sk_memory_order_release); 49 // An atomic load during process shutdown is probably overkill, but safe overkill. 50 atexit([]() { delete sk_atomic_load(&gUserTracer, sk_memory_order_acquire); }); 51 } 52 53 SkEventTracer* SkEventTracer::GetInstance() { 54 if (SkEventTracer* tracer = sk_atomic_load(&gUserTracer, sk_memory_order_acquire)) { 55 return tracer; 56 } 57 return gDefaultTracer.get([]{ return new SkDefaultEventTracer; }); 58 } 59
