Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 405 insertions, 0 deletions

diff --git a/mozglue/baseprofiler/public/BaseProfilerState.h b/mozglue/baseprofiler/public/BaseProfilerState.h
new file mode 100644
index 0000000000..15be2743a4
--- /dev/null
+++ b/mozglue/baseprofiler/public/BaseProfilerState.h
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+/* -*- 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/. */
+
+// The Gecko Profiler is an always-on profiler that takes fast and low overhead
+// samples of the program execution using only userspace functionality for
+// portability. The goal of this module is to provide performance data in a
+// generic cross-platform way without requiring custom tools or kernel support.
+//
+// Samples are collected to form a timeline with optional timeline event
+// (markers) used for filtering. The samples include both native stacks and
+// platform-independent "label stack" frames.
+
+#ifndef BaseProfilerState_h
+#define BaseProfilerState_h
+
+// This header contains most functions that give information about the Base
+// Profiler: Whether it is active or not, paused, the selected features, and
+// some generic process and thread information.
+// It is safe to include unconditionally, but uses of structs and functions must
+// be guarded by `#ifdef MOZ_GECKO_PROFILER`.
+
+#include "mozilla/BaseProfilerUtils.h"
+
+#ifndef MOZ_GECKO_PROFILER
+
+#  define AUTO_PROFILER_STATS(name)
+
+namespace mozilla::baseprofiler {
+
+[[nodiscard]] inline bool profiler_is_active() { return false; }
+[[nodiscard]] inline bool profiler_is_active_and_unpaused() { return false; }
+
+}  // namespace mozilla::baseprofiler
+
+#else  // !MOZ_GECKO_PROFILER
+
+#  include "mozilla/Atomics.h"
+#  include "mozilla/Maybe.h"
+
+#  include <stdint.h>
+#  include <string>
+
+// Uncomment the following line to display profiler runtime statistics at
+// shutdown.
+// #  define PROFILER_RUNTIME_STATS
+
+#  ifdef PROFILER_RUNTIME_STATS
+#    include "mozilla/TimeStamp.h"
+#  endif
+
+namespace mozilla::baseprofiler {
+
+#  ifdef PROFILER_RUNTIME_STATS
+// This class gathers durations and displays some basic stats when destroyed.
+// It is intended to be used as a static variable (see `AUTO_PROFILER_STATS`
+// below), to display stats at the end of the program.
+class StaticBaseProfilerStats {
+ public:
+  explicit StaticBaseProfilerStats(const char* aName) : mName(aName) {}
+
+  ~StaticBaseProfilerStats() {
+    // Using unsigned long long for computations and printfs.
+    using ULL = unsigned long long;
+    ULL n = static_cast<ULL>(mNumberDurations);
+    if (n != 0) {
+      ULL sumNs = static_cast<ULL>(mSumDurationsNs);
+      printf(
+          "[%d] Profiler stats `%s`: %llu ns / %llu = %llu ns, max %llu ns\n",
+          int(profiler_current_process_id().ToNumber()), mName, sumNs, n,
+          sumNs / n, static_cast<ULL>(mLongestDurationNs));
+    } else {
+      printf("[%d] Profiler stats `%s`: (nothing)\n",
+             int(profiler_current_process_id().ToNumber()), mName);
+    }
+  }
+
+  void AddDurationFrom(TimeStamp aStart) {
+    DurationNs duration = static_cast<DurationNs>(
+        (TimeStamp::Now() - aStart).ToMicroseconds() * 1000 + 0.5);
+    mSumDurationsNs += duration;
+    ++mNumberDurations;
+    // Update mLongestDurationNs if this one is longer.
+    for (;;) {
+      DurationNs longest = mLongestDurationNs;
+      if (MOZ_LIKELY(longest >= duration)) {
+        // This duration is not the longest, nothing to do.
+        break;
+      }
+      if (MOZ_LIKELY(mLongestDurationNs.compareExchange(longest, duration))) {
+        // Successfully updated `mLongestDurationNs` with the new value.
+        break;
+      }
+      // Otherwise someone else just updated `mLongestDurationNs`, we need to
+      // try again by looping.
+    }
+  }
+
+ private:
+  using DurationNs = uint64_t;
+  using Count = uint32_t;
+
+  Atomic<DurationNs> mSumDurationsNs{0};
+  Atomic<DurationNs> mLongestDurationNs{0};
+  Atomic<Count> mNumberDurations{0};
+  const char* mName;
+};
+
+// RAII object that measure its scoped lifetime duration and reports it to a
+// `StaticBaseProfilerStats`.
+class MOZ_RAII AutoProfilerStats {
+ public:
+  explicit AutoProfilerStats(StaticBaseProfilerStats& aStats)
+      : mStats(aStats), mStart(TimeStamp::Now()) {}
+
+  ~AutoProfilerStats() { mStats.AddDurationFrom(mStart); }
+
+ private:
+  StaticBaseProfilerStats& mStats;
+  TimeStamp mStart;
+};
+
+// Macro that should be used to collect basic statistics from measurements of
+// block durations, from where this macro is, until the end of its enclosing
+// scope. The name is used in the static variable name and when displaying stats
+// at the end of the program; Another location could use the same name but their
+// stats will not be combined, so use different name if these locations should
+// be distinguished.
+#    define AUTO_PROFILER_STATS(name)                                      \
+      static ::mozilla::baseprofiler::StaticBaseProfilerStats sStat##name( \
+          #name);                                                          \
+      ::mozilla::baseprofiler::AutoProfilerStats autoStat##name(sStat##name);
+
+#  else  // PROFILER_RUNTIME_STATS
+
+#    define AUTO_PROFILER_STATS(name)
+
+#  endif  // PROFILER_RUNTIME_STATS else
+
+//---------------------------------------------------------------------------
+// Profiler features
+//---------------------------------------------------------------------------
+
+#  if defined(__APPLE__) && defined(__aarch64__)
+#    define POWER_HELP "Sample per process power use"
+#  elif defined(__APPLE__) && defined(__x86_64__)
+#    define POWER_HELP \
+      "Record the power used by the entire system with each sample."
+#  elif defined(__linux__) && defined(__x86_64__)
+#    define POWER_HELP                                                \
+      "Record the power used by the entire system with each sample. " \
+      "Only available with Intel CPUs and requires setting "          \
+      "the sysctl kernel.perf_event_paranoid to 0."
+#  elif defined(_MSC_VER)
+#    define POWER_HELP                                                       \
+      "Record the value of every energy meter available on the system with " \
+      "each sample. Only available on Windows 11 with Intel CPUs."
+#  else
+#    define POWER_HELP "Not supported on this platform."
+#  endif
+
+// Higher-order macro containing all the feature info in one place. Define
+// |MACRO| appropriately to extract the relevant parts. Note that the number
+// values are used internally only and so can be changed without consequence.
+// Any changes to this list should also be applied to the feature list in
+// toolkit/components/extensions/schemas/geckoProfiler.json.
+// *** Synchronize with lists in ProfilerState.h and geckoProfiler.json ***
+#  define BASE_PROFILER_FOR_EACH_FEATURE(MACRO)                              \
+    MACRO(0, "java", Java, "Profile Java code, Android only")                \
+                                                                             \
+    MACRO(1, "js", JS,                                                       \
+          "Get the JS engine to expose the JS stack to the profiler")        \
+                                                                             \
+    MACRO(2, "mainthreadio", MainThreadIO, "Add main thread file I/O")       \
+                                                                             \
+    MACRO(3, "fileio", FileIO,                                               \
+          "Add file I/O from all profiled threads, implies mainthreadio")    \
+                                                                             \
+    MACRO(4, "fileioall", FileIOAll,                                         \
+          "Add file I/O from all threads, implies fileio")                   \
+                                                                             \
+    MACRO(5, "nomarkerstacks", NoMarkerStacks,                               \
+          "Markers do not capture stacks, to reduce overhead")               \
+                                                                             \
+    MACRO(6, "screenshots", Screenshots,                                     \
+          "Take a snapshot of the window on every composition")              \
+                                                                             \
+    MACRO(7, "seqstyle", SequentialStyle,                                    \
+          "Disable parallel traversal in styling")                           \
+                                                                             \
+    MACRO(8, "stackwalk", StackWalk,                                         \
+          "Walk the C++ stack, not available on all platforms")              \
+                                                                             \
+    MACRO(9, "jsallocations", JSAllocations,                                 \
+          "Have the JavaScript engine track allocations")                    \
+                                                                             \
+    MACRO(10, "nostacksampling", NoStackSampling,                            \
+          "Disable all stack sampling: Cancels \"js\", \"stackwalk\" and "   \
+          "labels")                                                          \
+                                                                             \
+    MACRO(11, "nativeallocations", NativeAllocations,                        \
+          "Collect the stacks from a smaller subset of all native "          \
+          "allocations, biasing towards collecting larger allocations")      \
+                                                                             \
+    MACRO(12, "ipcmessages", IPCMessages,                                    \
+          "Have the IPC layer track cross-process messages")                 \
+                                                                             \
+    MACRO(13, "audiocallbacktracing", AudioCallbackTracing,                  \
+          "Audio callback tracing")                                          \
+                                                                             \
+    MACRO(14, "cpu", CPUUtilization, "CPU utilization")                      \
+                                                                             \
+    MACRO(15, "notimerresolutionchange", NoTimerResolutionChange,            \
+          "Do not adjust the timer resolution for fast sampling, so that "   \
+          "other Firefox timers do not get affected")                        \
+                                                                             \
+    MACRO(16, "cpuallthreads", CPUAllThreads,                                \
+          "Sample the CPU utilization of all registered threads")            \
+                                                                             \
+    MACRO(17, "samplingallthreads", SamplingAllThreads,                      \
+          "Sample the stacks of all registered threads")                     \
+                                                                             \
+    MACRO(18, "markersallthreads", MarkersAllThreads,                        \
+          "Record markers from all registered threads")                      \
+                                                                             \
+    MACRO(19, "unregisteredthreads", UnregisteredThreads,                    \
+          "Discover and profile unregistered threads -- beware: expensive!") \
+                                                                             \
+    MACRO(20, "processcpu", ProcessCPU,                                      \
+          "Sample the CPU utilization of each process")                      \
+                                                                             \
+    MACRO(21, "power", Power, POWER_HELP)
+// *** Synchronize with lists in ProfilerState.h and geckoProfiler.json ***
+
+struct ProfilerFeature {
+#  define DECLARE(n_, str_, Name_, desc_)                                \
+    static constexpr uint32_t Name_ = (1u << n_);                        \
+    [[nodiscard]] static constexpr bool Has##Name_(uint32_t aFeatures) { \
+      return aFeatures & Name_;                                          \
+    }                                                                    \
+    static constexpr void Set##Name_(uint32_t& aFeatures) {              \
+      aFeatures |= Name_;                                                \
+    }                                                                    \
+    static constexpr void Clear##Name_(uint32_t& aFeatures) {            \
+      aFeatures &= ~Name_;                                               \
+    }
+
+  // Define a bitfield constant, a getter, and two setters for each feature.
+  BASE_PROFILER_FOR_EACH_FEATURE(DECLARE)
+
+#  undef DECLARE
+};
+
+namespace detail {
+
+// RacyFeatures is only defined in this header file so that its methods can
+// be inlined into profiler_is_active(). Please do not use anything from the
+// detail namespace outside the profiler.
+
+// Within the profiler's code, the preferred way to check profiler activeness
+// and features is via ActivePS(). However, that requires locking gPSMutex.
+// There are some hot operations where absolute precision isn't required, so we
+// duplicate the activeness/feature state in a lock-free manner in this class.
+class RacyFeatures {
+ public:
+  MFBT_API static void SetActive(uint32_t aFeatures);
+
+  MFBT_API static void SetInactive();
+
+  MFBT_API static void SetPaused();
+
+  MFBT_API static void SetUnpaused();
+
+  MFBT_API static void SetSamplingPaused();
+
+  MFBT_API static void SetSamplingUnpaused();
+
+  [[nodiscard]] MFBT_API static mozilla::Maybe<uint32_t> FeaturesIfActive() {
+    if (uint32_t af = sActiveAndFeatures; af & Active) {
+      // Active, remove the Active&Paused bits to get all features.
+      return Some(af & ~(Active | Paused | SamplingPaused));
+    }
+    return Nothing();
+  }
+
+  [[nodiscard]] MFBT_API static bool IsActive();
+
+  [[nodiscard]] MFBT_API static bool IsActiveWithFeature(uint32_t aFeature);
+
+  [[nodiscard]] MFBT_API static bool IsActiveWithoutFeature(uint32_t aFeature);
+
+  // True if profiler is active, and not fully paused.
+  // Note that periodic sampling *could* be paused!
+  [[nodiscard]] MFBT_API static bool IsActiveAndUnpaused();
+
+  // True if profiler is active, and sampling is not paused (though generic
+  // `SetPaused()` or specific `SetSamplingPaused()`).
+  [[nodiscard]] MFBT_API static bool IsActiveAndSamplingUnpaused();
+
+ private:
+  static constexpr uint32_t Active = 1u << 31;
+  static constexpr uint32_t Paused = 1u << 30;
+  static constexpr uint32_t SamplingPaused = 1u << 29;
+
+// Ensure Active/Paused don't overlap with any of the feature bits.
+#  define NO_OVERLAP(n_, str_, Name_, desc_)                \
+    static_assert(ProfilerFeature::Name_ != SamplingPaused, \
+                  "bad feature value");
+
+  BASE_PROFILER_FOR_EACH_FEATURE(NO_OVERLAP);
+
+#  undef NO_OVERLAP
+
+  // We combine the active bit with the feature bits so they can be read or
+  // written in a single atomic operation.
+  // TODO: Could this be MFBT_DATA for better inlining optimization?
+  static Atomic<uint32_t, MemoryOrdering::Relaxed> sActiveAndFeatures;
+};
+
+MFBT_API bool IsThreadBeingProfiled();
+
+}  // namespace detail
+
+//---------------------------------------------------------------------------
+// Get information from the profiler
+//---------------------------------------------------------------------------
+
+// Is the profiler active? Note: the return value of this function can become
+// immediately out-of-date. E.g. the profile might be active but then
+// profiler_stop() is called immediately afterward. One common and reasonable
+// pattern of usage is the following:
+//
+//   if (profiler_is_active()) {
+//     ExpensiveData expensiveData = CreateExpensiveData();
+//     PROFILER_OPERATION(expensiveData);
+//   }
+//
+// where PROFILER_OPERATION is a no-op if the profiler is inactive. In this
+// case the profiler_is_active() check is just an optimization -- it prevents
+// us calling CreateExpensiveData() unnecessarily in most cases, but the
+// expensive data will end up being created but not used if another thread
+// stops the profiler between the CreateExpensiveData() and PROFILER_OPERATION
+// calls.
+[[nodiscard]] inline bool profiler_is_active() {
+  return baseprofiler::detail::RacyFeatures::IsActive();
+}
+
+// Same as profiler_is_active(), but also checks if the profiler is not paused.
+[[nodiscard]] inline bool profiler_is_active_and_unpaused() {
+  return baseprofiler::detail::RacyFeatures::IsActiveAndUnpaused();
+}
+
+// Is the profiler active and unpaused, and is the current thread being
+// profiled? (Same caveats and recommented usage as profiler_is_active().)
+[[nodiscard]] inline bool profiler_thread_is_being_profiled() {
+  return baseprofiler::detail::RacyFeatures::IsActiveAndUnpaused() &&
+         baseprofiler::detail::IsThreadBeingProfiled();
+}
+
+// Is the profiler active and paused? Returns false if the profiler is inactive.
+[[nodiscard]] MFBT_API bool profiler_is_paused();
+
+// Is the profiler active and sampling is paused? Returns false if the profiler
+// is inactive.
+[[nodiscard]] MFBT_API bool profiler_is_sampling_paused();
+
+// Is the current thread sleeping?
+[[nodiscard]] MFBT_API bool profiler_thread_is_sleeping();
+
+// Get all the features supported by the profiler that are accepted by
+// profiler_start(). The result is the same whether the profiler is active or
+// not.
+[[nodiscard]] MFBT_API uint32_t profiler_get_available_features();
+
+// Returns the full feature set if the profiler is active.
+// Note: the return value can become immediately out-of-date, much like the
+// return value of profiler_is_active().
+[[nodiscard]] inline mozilla::Maybe<uint32_t> profiler_features_if_active() {
+  return baseprofiler::detail::RacyFeatures::FeaturesIfActive();
+}
+
+// Check if a profiler feature (specified via the ProfilerFeature type) is
+// active. Returns false if the profiler is inactive. Note: the return value
+// can become immediately out-of-date, much like the return value of
+// profiler_is_active().
+[[nodiscard]] MFBT_API bool profiler_feature_active(uint32_t aFeature);
+
+// Check if the profiler is active without a feature (specified via the
+// ProfilerFeature type). Note: the return value can become immediately
+// out-of-date, much like the return value of profiler_is_active().
+[[nodiscard]] MFBT_API bool profiler_active_without_feature(uint32_t aFeature);
+
+// Returns true if any of the profiler mutexes are currently locked *on the
+// current thread*. This may be used by re-entrant code that may call profiler
+// functions while the same of a different profiler mutex is locked, which could
+// deadlock.
+[[nodiscard]] bool profiler_is_locked_on_current_thread();
+
+}  // namespace mozilla::baseprofiler
+
+#endif  // !MOZ_GECKO_PROFILER
+
+#endif  // BaseProfilerState_h