1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
7 #include "mozilla/AutoProfilerLabel.h"
9 #include "mozilla/Assertions.h"
10 #include "mozilla/PlatformMutex.h"
14 // RAII class that encapsulates all shared static data, and enforces locking
15 // when accessing this data.
16 class MOZ_RAII AutoProfilerLabelData
{
18 AutoProfilerLabelData() { sAPLMutex
.Lock(); }
20 ~AutoProfilerLabelData() { sAPLMutex
.Unlock(); }
22 AutoProfilerLabelData(const AutoProfilerLabelData
&) = delete;
23 void operator=(const AutoProfilerLabelData
&) = delete;
25 const ProfilerLabelEnter
& EnterCRef() const { return sEnter
; }
26 ProfilerLabelEnter
& EnterRef() { return sEnter
; }
28 const ProfilerLabelExit
& ExitCRef() const { return sExit
; }
29 ProfilerLabelExit
& ExitRef() { return sExit
; }
31 const uint32_t& GenerationCRef() const { return sGeneration
; }
32 uint32_t& GenerationRef() { return sGeneration
; }
34 static bool RacyIsProfilerPresent() { return !!sGeneration
; }
37 // Thin shell around mozglue PlatformMutex, for local internal use.
38 // Does not preserve behavior in JS record/replay.
39 class Mutex
: private mozilla::detail::MutexImpl
{
42 void Lock() { mozilla::detail::MutexImpl::lock(); }
43 void Unlock() { mozilla::detail::MutexImpl::unlock(); }
46 // Mutex protecting access to the following static members.
47 static Mutex sAPLMutex MOZ_UNANNOTATED
;
49 static ProfilerLabelEnter sEnter
;
50 static ProfilerLabelExit sExit
;
52 // Current "generation" of RegisterProfilerLabelEnterExit calls.
53 static uint32_t sGeneration
;
56 /* static */ AutoProfilerLabelData::Mutex
AutoProfilerLabelData::sAPLMutex
;
57 /* static */ ProfilerLabelEnter
AutoProfilerLabelData::sEnter
= nullptr;
58 /* static */ ProfilerLabelExit
AutoProfilerLabelData::sExit
= nullptr;
59 /* static */ uint32_t AutoProfilerLabelData::sGeneration
= 0;
61 void RegisterProfilerLabelEnterExit(ProfilerLabelEnter aEnter
,
62 ProfilerLabelExit aExit
) {
63 MOZ_ASSERT(!aEnter
== !aExit
, "Must provide both null or both non-null");
65 AutoProfilerLabelData data
;
66 MOZ_ASSERT(!aEnter
!= !data
.EnterRef(),
67 "Must go from null to non-null, or from non-null to null");
68 data
.EnterRef() = aEnter
;
69 data
.ExitRef() = aExit
;
70 ++data
.GenerationRef();
73 bool IsProfilerPresent() {
74 return AutoProfilerLabelData::RacyIsProfilerPresent();
77 ProfilerLabel
ProfilerLabelBegin(const char* aLabelName
,
78 const char* aDynamicString
, void* aSp
) {
79 const AutoProfilerLabelData data
;
80 void* entryContext
= (data
.EnterCRef())
81 ? data
.EnterCRef()(aLabelName
, aDynamicString
, aSp
)
83 uint32_t generation
= data
.GenerationCRef();
85 return std::make_tuple(entryContext
, generation
);
88 void ProfilerLabelEnd(const ProfilerLabel
& aLabel
) {
89 if (!IsValidProfilerLabel(aLabel
)) {
93 const AutoProfilerLabelData data
;
94 if (data
.ExitCRef() && (std::get
<1>(aLabel
) == data
.GenerationCRef())) {
95 data
.ExitCRef()(std::get
<0>(aLabel
));
99 AutoProfilerLabel::AutoProfilerLabel(const char* aLabel
,
100 const char* aDynamicString
) {
101 std::tie(mEntryContext
, mGeneration
) =
102 ProfilerLabelBegin(aLabel
, aDynamicString
, this);
105 AutoProfilerLabel::~AutoProfilerLabel() {
106 ProfilerLabelEnd(std::make_tuple(mEntryContext
, mGeneration
));
109 } // namespace mozilla