diff --git a/compiler-rt/lib/scudo/standalone/CMakeLists.txt b/compiler-rt/lib/scudo/standalone/CMakeLists.txt --- a/compiler-rt/lib/scudo/standalone/CMakeLists.txt +++ b/compiler-rt/lib/scudo/standalone/CMakeLists.txt @@ -85,6 +85,7 @@ stack_depot.h stats.h string_utils.h + timing.h tsd_exclusive.h tsd_shared.h tsd.h @@ -107,6 +108,7 @@ report.cpp rss_limit_checker.cpp string_utils.cpp + timing.cpp ) # Enable the necessary instruction set for scudo_crc32.cpp, if available. diff --git a/compiler-rt/lib/scudo/standalone/tests/CMakeLists.txt b/compiler-rt/lib/scudo/standalone/tests/CMakeLists.txt --- a/compiler-rt/lib/scudo/standalone/tests/CMakeLists.txt +++ b/compiler-rt/lib/scudo/standalone/tests/CMakeLists.txt @@ -105,6 +105,7 @@ size_class_map_test.cpp stats_test.cpp strings_test.cpp + timing_test.cpp tsd_test.cpp vector_test.cpp scudo_unit_test_main.cpp diff --git a/compiler-rt/lib/scudo/standalone/tests/timing_test.cpp b/compiler-rt/lib/scudo/standalone/tests/timing_test.cpp new file mode 100644 --- /dev/null +++ b/compiler-rt/lib/scudo/standalone/tests/timing_test.cpp @@ -0,0 +1,55 @@ +//===-- timing_test.cpp -----------------------------------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "tests/scudo_unit_test.h" + +#include "timing.h" + +#include + +class ScudoTimingTest : public Test { +public: + void testFunc1() { scudo::ScopedTimer ST(Manager, __func__); } + + void testFunc2() { + scudo::ScopedTimer ST(Manager, __func__); + testFunc1(); + } + + void testChainedCalls() { + scudo::ScopedTimer ST(Manager, __func__); + testFunc2(); + } + + void printAllTimersStats() { Manager.printAll(); } + + scudo::TimingManager &getTimingManager() { return Manager; } + +private: + scudo::TimingManager Manager; +}; + +// Given that the output of statistics of timers are dumped through +// `scudo::Printf` which is platform dependent, so we don't have a reliable way +// to catch the output and verify the content. Now we only ensure the execution +// is well-performed. +TEST_F(ScudoTimingTest, SimpleTimer) { + testChainedCalls(); + printAllTimersStats(); +} + +TEST_F(ScudoTimingTest, NestedTimer) { + { + scudo::ScopedTimer Outer(getTimingManager(), "Outer"); + { + scudo::ScopedTimer Inner1(getTimingManager(), Outer, "Inner1"); + { scudo::ScopedTimer Inner2(getTimingManager(), Inner1, "Inner2"); } + } + } + printAllTimersStats(); +} diff --git a/compiler-rt/lib/scudo/standalone/timing.h b/compiler-rt/lib/scudo/standalone/timing.h new file mode 100644 --- /dev/null +++ b/compiler-rt/lib/scudo/standalone/timing.h @@ -0,0 +1,200 @@ +//===-- timing.h ------------------------------------------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "common.h" +#include "mutex.h" +#include "string_utils.h" +#include "thread_annotations.h" + +#include + +namespace scudo { + +class TimingManager; + +// A simple timer for evaluating execution time of code snippets. It can be used +// along with TimingManager or standalone. +class Timer { +public: + Timer() = default; + Timer(Timer &&Other) + : StartTime(0), AccTime(Other.AccTime), Manager(Other.Manager), + HandleId(Other.HandleId) { + Other.Manager = nullptr; + } + + Timer(const Timer &) = delete; + + virtual ~Timer(); + + void start() { + DCHECK_EQ(StartTime, 0U); + StartTime = getMonotonicTime(); + } + void stop() { + AccTime += getMonotonicTime() - StartTime; + StartTime = 0; + } + u64 getAcculatedTime() const { return AccTime; } + +protected: + friend class TimingManager; + Timer(TimingManager &Manager, u32 HandleId) + : Manager(&Manager), HandleId(HandleId) {} + + u64 StartTime = 0; + u64 AccTime = 0; + TimingManager *Manager = nullptr; + u32 HandleId; +}; + +// A RAII-style wrapper for easy scope execution measurement. Note that in order +// not to take additional space for the message like `Name`. It only works with +// TimingManager. +class ScopedTimer : public Timer { +public: + ScopedTimer(TimingManager &Manager, const char *Name); + ScopedTimer(TimingManager &Manager, const Timer &Nest, const char *Name); + ~ScopedTimer() override { stop(); } +}; + +// In Scudo, the execution time of single run of code snippets may not be +// useful, we are more interested in the average time from several runs. +// TimingManager lets the registered timer report their data and reports the +// average execution time for each timer periodically. +class TimingManager { +public: + TimingManager(u32 PrintingInterval = DefaultPrintingInterval) + : PrintingInterval(PrintingInterval) {} + ~TimingManager() { + if (NumAllocatedTimers != 0) + printAll(); + } + + Timer getOrCreateTimer(const char *Name) EXCLUDES(Mutex) { + ScopedLock L(Mutex); + + DCHECK_LT(strlen(Name), MaxLenOfTimerName); + for (u32 I = 0; I < NumAllocatedTimers; ++I) { + if (strncmp(Name, Timers[I].Name, MaxLenOfTimerName) == 0) + return Timer(*this, I); + } + + DCHECK_LT(NumAllocatedTimers, MaxNumberOfTimers); + strncpy(Timers[NumAllocatedTimers].Name, Name, MaxLenOfTimerName); + TimerRecords[NumAllocatedTimers].AccumulatedTime = 0; + TimerRecords[NumAllocatedTimers].Occurrence = 0; + return Timer(*this, NumAllocatedTimers++); + } + + // Add a sub-Timer associated with another Timer. This is used when we want to + // detail the execution time in the scope of a Timer. + // For example, + // void Foo() { + // // T2 records the time spent in both first and second tasks. + // ScopedTimer T1(getTimingManager(), "Task1"); + // { + // // T2 records the time spent in first task + // ScopedTimer T2(getTimingManager, T1, "Task2"); + // // Do first task. + // } + // // Do second task. + // } + // + // The report will show proper indents to indicate the nested relation like, + // -- Average Operation Time -- -- Name (# of Calls) -- + // 10.0(ns) Task1 (1) + // 5.0(na) Task2 (1) + Timer nest(const Timer &T, const char *Name) EXCLUDES(Mutex) { + Timer Nesting = getOrCreateTimer(Name); + + ScopedLock L(Mutex); + DCHECK_NE(Nesting.HandleId, T.HandleId); + Timers[Nesting.HandleId].Nesting = T.HandleId; + return Nesting; + } + + void report(const Timer &T) EXCLUDES(Mutex) { + ScopedLock L(Mutex); + + const u32 HandleId = T.HandleId; + DCHECK_LT(HandleId, MaxNumberOfTimers); + TimerRecords[HandleId].AccumulatedTime += T.getAcculatedTime(); + ++TimerRecords[HandleId].Occurrence; + ++NumEventsReported; + if (NumEventsReported % PrintingInterval == 0) + printAllImpl(); + } + + void printAll() EXCLUDES(Mutex) { + ScopedLock L(Mutex); + printAllImpl(); + } + +private: + void printAllImpl() REQUIRES(Mutex) { + static char NameHeader[] = "-- Name (# of Calls) --"; + static char AvgHeader[] = "-- Average Operation Time --"; + Printf("%-15s %-15s\n", AvgHeader, NameHeader); + + for (u32 I = 0; I < NumAllocatedTimers; ++I) { + if (Timers[I].Nesting != MaxNumberOfTimers) + continue; + printImpl(I); + } + } + + void printImpl(const u32 HandleId, const u32 ExtraIndent = 0) + REQUIRES(Mutex) { + const uptr AccumulatedTime = TimerRecords[HandleId].AccumulatedTime; + const uptr Occurrence = TimerRecords[HandleId].Occurrence; + const uptr Integral = Occurrence == 0 ? 0 : AccumulatedTime / Occurrence; + // Only keep single digit of fraction is enough and it enables easier layout + // maintance. + const uptr Fraction = + Occurrence == 0 ? 0 + : ((AccumulatedTime % Occurrence) * 10) / Occurrence; + + Printf("%12zu.%zu(ns) %-11s", Integral, Fraction, " "); + + for (u32 I = 0; I < ExtraIndent; ++I) + Printf("%s", " "); + Printf("%s (%zu)\n", Timers[HandleId].Name, Occurrence); + + for (u32 I = 0; I < NumAllocatedTimers; ++I) + if (Timers[I].Nesting == HandleId) + printImpl(I, ExtraIndent + 1); + } + + // Instead of maintaining pages for timer registration, a static buffer is + // sufficient for most use cases in Scudo. + static constexpr u32 MaxNumberOfTimers = 30; + static constexpr u32 MaxLenOfTimerName = 30; + static constexpr u32 DefaultPrintingInterval = 100; + + struct Record { + uptr AccumulatedTime = 0; + uptr Occurrence = 0; + }; + + struct TimerInfo { + char Name[MaxLenOfTimerName]; + u32 Nesting = MaxNumberOfTimers; + }; + + HybridMutex Mutex; + // The frequency of proactively dumping the timer statistics. For example, the + // default setting is to dump the statistics every 100 reported events. + u32 PrintingInterval GUARDED_BY(Mutex); + uptr NumEventsReported GUARDED_BY(Mutex) = 0; + u32 NumAllocatedTimers GUARDED_BY(Mutex) = 0; + TimerInfo Timers[MaxNumberOfTimers] GUARDED_BY(Mutex); + Record TimerRecords[MaxNumberOfTimers] GUARDED_BY(Mutex); +}; + +} // namespace scudo diff --git a/compiler-rt/lib/scudo/standalone/timing.cpp b/compiler-rt/lib/scudo/standalone/timing.cpp new file mode 100644 --- /dev/null +++ b/compiler-rt/lib/scudo/standalone/timing.cpp @@ -0,0 +1,29 @@ +//===-- timing.cpp ----------------------------------------------*- C++ -*-===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "timing.h" + +namespace scudo { + +Timer::~Timer() { + if (Manager) + Manager->report(*this); +} + +ScopedTimer::ScopedTimer(TimingManager &Manager, const char *Name) + : Timer(Manager.getOrCreateTimer(Name)) { + start(); +} + +ScopedTimer::ScopedTimer(TimingManager &Manager, const Timer &Nest, + const char *Name) + : Timer(Manager.nest(Nest, Name)) { + start(); +} + +} // namespace scudo