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 "SkLazyPtr.h"
11
12 class SkDefaultEventTracer : public SkEventTracer {
13 SkEventTracer::Handle
addTraceEvent(char phase,const uint8_t * categoryEnabledFlag,const char * name,uint64_t id,int numArgs,const char ** argNames,const uint8_t * argTypes,const uint64_t * argValues,uint8_t flags)14 addTraceEvent(char phase,
15 const uint8_t* categoryEnabledFlag,
16 const char* name,
17 uint64_t id,
18 int numArgs,
19 const char** argNames,
20 const uint8_t* argTypes,
21 const uint64_t* argValues,
22 uint8_t flags) override { return 0; }
23
24 void
updateTraceEventDuration(const uint8_t * categoryEnabledFlag,const char * name,SkEventTracer::Handle handle)25 updateTraceEventDuration(const uint8_t* categoryEnabledFlag,
26 const char* name,
27 SkEventTracer::Handle handle) override {}
28
getCategoryGroupEnabled(const char * name)29 const uint8_t* getCategoryGroupEnabled(const char* name) override {
30 static uint8_t no = 0;
31 return &no;
32 }
getCategoryGroupName(const uint8_t * categoryEnabledFlag)33 const char* getCategoryGroupName(
34 const uint8_t* categoryEnabledFlag) override {
35 static const char* dummy = "dummy";
36 return dummy;
37 }
38 };
39
40 // We prefer gUserTracer if it's been set, otherwise we fall back on gDefaultTracer.
41 static SkEventTracer* gUserTracer = nullptr;
42 SK_DECLARE_STATIC_LAZY_PTR(SkDefaultEventTracer, gDefaultTracer);
43
SetInstance(SkEventTracer * tracer)44 void SkEventTracer::SetInstance(SkEventTracer* tracer) {
45 SkASSERT(nullptr == sk_atomic_load(&gUserTracer, sk_memory_order_acquire));
46 sk_atomic_store(&gUserTracer, tracer, sk_memory_order_release);
47 // An atomic load during process shutdown is probably overkill, but safe overkill.
48 atexit([](){ SkDELETE(sk_atomic_load(&gUserTracer, sk_memory_order_acquire)); });
49 }
50
GetInstance()51 SkEventTracer* SkEventTracer::GetInstance() {
52 if (SkEventTracer* tracer = sk_atomic_load(&gUserTracer, sk_memory_order_acquire)) {
53 return tracer;
54 }
55 return gDefaultTracer.get();
56 }
57