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Diffstat (limited to 'tools/profiler/public/ProfilerCounts.h')
| -rw-r--r-- | tools/profiler/public/ProfilerCounts.h | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/tools/profiler/public/ProfilerCounts.h b/tools/profiler/public/ProfilerCounts.h new file mode 100644 index 0000000000..cebca81e2c --- /dev/null +++ b/tools/profiler/public/ProfilerCounts.h @@ -0,0 +1,297 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef ProfilerCounts_h +#define ProfilerCounts_h + +#ifndef MOZ_GECKO_PROFILER + +# define PROFILER_DEFINE_COUNT_TOTAL(label, category, description) +# define PROFILER_DEFINE_COUNT(label, category, description) +# define PROFILER_DEFINE_STATIC_COUNT_TOTAL(label, category, description) +# define AUTO_PROFILER_TOTAL(label, count) +# define AUTO_PROFILER_COUNT(label) +# define AUTO_PROFILER_STATIC_COUNT(label, count) + +#else + +# include "mozilla/Assertions.h" +# include "mozilla/Atomics.h" + +class BaseProfilerCount; +void profiler_add_sampled_counter(BaseProfilerCount* aCounter); +void profiler_remove_sampled_counter(BaseProfilerCount* aCounter); + +typedef mozilla::Atomic<int64_t, mozilla::MemoryOrdering::Relaxed> + ProfilerAtomicSigned; +typedef mozilla::Atomic<uint64_t, mozilla::MemoryOrdering::Relaxed> + ProfilerAtomicUnsigned; + +// Counter support +// There are two types of counters: +// 1) a simple counter which can be added to or subtracted from. This could +// track the number of objects of a type, the number of calls to something +// (reflow, JIT, etc). +// 2) a combined counter which has the above, plus a number-of-calls counter +// that is incremented by 1 for each call to modify the count. This provides +// an optional source for a 'heatmap' of access. This can be used (for +// example) to track the amount of memory allocated, and provide a heatmap of +// memory operations (allocs/frees). +// +// Counters are sampled by the profiler once per sample-period. At this time, +// all counters are global to the process. In the future, there might be more +// versions with per-thread or other discriminators. +// +// Typical usage: +// There are two ways to use counters: With heap-created counter objects, +// or using macros. Note: the macros use statics, and will be slightly +// faster/smaller, and you need to care about creating them before using +// them. They're similar to the use-pattern for the other AUTO_PROFILER* +// macros, but they do need the PROFILER_DEFINE* to be use to instantiate +// the statics. +// +// PROFILER_DEFINE_COUNT(mything, "JIT", "Some JIT byte count") +// ... +// void foo() { ... AUTO_PROFILER_COUNT(mything, number_of_bytes_used); ... } +// +// or (to also get a heatmap) +// +// PROFILER_DEFINE_COUNT_TOTAL(mything, "JIT", "Some JIT byte count") +// ... +// void foo() { +// ... +// AUTO_PROFILER_COUNT_TOTAL(mything, number_of_bytes_generated); +// ... +// } +// +// To use without statics/macros: +// +// UniquePtr<ProfilerCounter> myCounter; +// ... +// myCounter = +// MakeUnique<ProfilerCounter>("mything", "JIT", "Some JIT byte count")); +// ... +// void foo() { ... myCounter->Add(number_of_bytes_generated0; ... } + +class BaseProfilerCount { + public: + BaseProfilerCount(const char* aLabel, ProfilerAtomicSigned* aCounter, + ProfilerAtomicUnsigned* aNumber, const char* aCategory, + const char* aDescription) + : mLabel(aLabel), + mCategory(aCategory), + mDescription(aDescription), + mCounter(aCounter), + mNumber(aNumber) { +# define COUNTER_CANARY 0xDEADBEEF +# ifdef DEBUG + mCanary = COUNTER_CANARY; + mPrevNumber = 0; +# endif + // Can't call profiler_* here since this may be non-xul-library + } + + virtual ~BaseProfilerCount() { +# ifdef DEBUG + mCanary = 0; +# endif + } + + struct CountSample { + int64_t count; + uint64_t number; + // This field indicates if the sample has already been consummed by a call + // to the Sample() method. This allows the profiler to discard duplicate + // samples if the counter sampling rate is lower than the profiler sampling + // rate. This can happen for example with some power meters that sample up + // to every 10ms. + // It should always be true when calling Sample() for the first time. + bool isSampleNew; + }; + virtual CountSample Sample() { + MOZ_ASSERT(mCanary == COUNTER_CANARY); + + CountSample result; + result.count = *mCounter; + result.number = mNumber ? *mNumber : 0; +# ifdef DEBUG + MOZ_ASSERT(result.number >= mPrevNumber); + mPrevNumber = result.number; +# endif + result.isSampleNew = true; + return result; + } + + void Clear() { + *mCounter = 0; + // We don't reset *mNumber or mPrevNumber. We encode numbers as + // positive deltas, and currently we only care about the deltas (for + // e.g. heatmaps). If we ever need to clear mNumber as well, we can an + // alternative method (Reset()) to do so. + } + + // We don't define ++ and Add() here, since the static defines directly + // increment the atomic counters, and the subclasses implement ++ and + // Add() directly. + + // These typically are static strings (for example if you use the macros + // below) + const char* mLabel; + const char* mCategory; + const char* mDescription; + // We're ok with these being un-ordered in race conditions. These are + // pointers because we want to be able to use statics and increment them + // directly. Otherwise we could just have them inline, and not need the + // constructor args. + // These can be static globals (using the macros below), though they + // don't have to be - their lifetime must be longer than the use of them + // by the profiler (see profiler_add/remove_sampled_counter()). If you're + // using a lot of these, they probably should be allocated at runtime (see + // class ProfilerCountOnly below). + ProfilerAtomicSigned* mCounter; + ProfilerAtomicUnsigned* mNumber; // may be null + +# ifdef DEBUG + uint32_t mCanary; + uint64_t mPrevNumber; // value of number from the last Sample() +# endif +}; + +// Designed to be allocated dynamically, and simply incremented with obj++ +// or obj->Add(n) +class ProfilerCounter final : public BaseProfilerCount { + public: + ProfilerCounter(const char* aLabel, const char* aCategory, + const char* aDescription) + : BaseProfilerCount(aLabel, &mCounter, nullptr, aCategory, aDescription) { + // Assume we're in libxul + profiler_add_sampled_counter(this); + } + + virtual ~ProfilerCounter() { profiler_remove_sampled_counter(this); } + + BaseProfilerCount& operator++() { + Add(1); + return *this; + } + + void Add(int64_t aNumber) { mCounter += aNumber; } + + ProfilerAtomicSigned mCounter; +}; + +// Also keeps a heatmap (number of calls to ++/Add()) +class ProfilerCounterTotal final : public BaseProfilerCount { + public: + ProfilerCounterTotal(const char* aLabel, const char* aCategory, + const char* aDescription) + : BaseProfilerCount(aLabel, &mCounter, &mNumber, aCategory, + aDescription) { + // Assume we're in libxul + profiler_add_sampled_counter(this); + } + + virtual ~ProfilerCounterTotal() { profiler_remove_sampled_counter(this); } + + BaseProfilerCount& operator++() { + Add(1); + return *this; + } + + void Add(int64_t aNumber) { + mCounter += aNumber; + mNumber++; + } + + ProfilerAtomicSigned mCounter; + ProfilerAtomicUnsigned mNumber; +}; + +// Defines a counter that is sampled on each profiler tick, with a running +// count (signed), and number-of-instances. Note that because these are two +// independent Atomics, there is a possiblity that count will not include +// the last call, but number of uses will. I think this is not worth +// worrying about +# define PROFILER_DEFINE_COUNT_TOTAL(label, category, description) \ + ProfilerAtomicSigned profiler_count_##label(0); \ + ProfilerAtomicUnsigned profiler_number_##label(0); \ + const char profiler_category_##label[] = category; \ + const char profiler_description_##label[] = description; \ + mozilla::UniquePtr<BaseProfilerCount> AutoCount_##label; + +// This counts, but doesn't keep track of the number of calls to +// AUTO_PROFILER_COUNT() +# define PROFILER_DEFINE_COUNT(label, category, description) \ + ProfilerAtomicSigned profiler_count_##label(0); \ + const char profiler_category_##label[] = category; \ + const char profiler_description_##label[] = description; \ + mozilla::UniquePtr<BaseProfilerCount> AutoCount_##label; + +// This will create a static initializer if used, but avoids a possible +// allocation. +# define PROFILER_DEFINE_STATIC_COUNT_TOTAL(label, category, description) \ + ProfilerAtomicSigned profiler_count_##label(0); \ + ProfilerAtomicUnsigned profiler_number_##label(0); \ + BaseProfilerCount AutoCount_##label(#label, &profiler_count_##label, \ + &profiler_number_##label, category, \ + description); + +// If we didn't care about static initializers, we could avoid the need for +// a ptr to the BaseProfilerCount object. + +// XXX It would be better to do this without the if() and without the +// theoretical race to set the UniquePtr (i.e. possible leak). +# define AUTO_PROFILER_COUNT_TOTAL(label, count) \ + do { \ + profiler_number_##label++; /* do this first*/ \ + profiler_count_##label += count; \ + if (!AutoCount_##label) { \ + /* Ignore that we could call this twice in theory, and that we leak \ + * them \ + */ \ + AutoCount_##label.reset(new BaseProfilerCount( \ + #label, &profiler_count_##label, &profiler_number_##label, \ + profiler_category_##label, profiler_description_##label)); \ + profiler_add_sampled_counter(AutoCount_##label.get()); \ + } \ + } while (0) + +# define AUTO_PROFILER_COUNT(label, count) \ + do { \ + profiler_count_##label += count; /* do this first*/ \ + if (!AutoCount_##label) { \ + /* Ignore that we could call this twice in theory, and that we leak \ + * them \ + */ \ + AutoCount_##label.reset(new BaseProfilerCount( \ + #label, nullptr, &profiler_number_##label, \ + profiler_category_##label, profiler_description_##label)); \ + profiler_add_sampled_counter(AutoCount_##label.get()); \ + } \ + } while (0) + +# define AUTO_PROFILER_STATIC_COUNT(label, count) \ + do { \ + profiler_number_##label++; /* do this first*/ \ + profiler_count_##label += count; \ + } while (0) + +// if we need to force the allocation +# define AUTO_PROFILER_FORCE_ALLOCATION(label) \ + do { \ + if (!AutoCount_##label) { \ + /* Ignore that we could call this twice in theory, and that we leak \ + * them \ + */ \ + AutoCount_##label.reset(new BaseProfilerCount( \ + #label, &profiler_count_##label, &profiler_number_##label, \ + profiler_category_##label, profiler_description_##label)); \ + } \ + } while (0) + +#endif // !MOZ_GECKO_PROFILER + +#endif // ProfilerCounts_h |