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/* -*- Mode: C++; tab-width: 8; 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
#ifndef mozilla_CPUUsageWatcher_h
#define mozilla_CPUUsageWatcher_h
#include <stdint.h>
#include "mozilla/HangAnnotations.h"
#include "mozilla/Result.h"
// We only support OSX and Windows, because on Linux we're forced to read
// from /proc/stat in order to get global CPU values. We would prefer to not
// eat that cost for this.
#if defined(NIGHTLY_BUILD) && (defined(XP_WIN) || defined(XP_MACOSX))
# define CPU_USAGE_WATCHER_ACTIVE
#endif
namespace mozilla {
// Start error values at 1 to allow using the UnusedZero Result
// optimization.
enum CPUUsageWatcherError : uint8_t {
ClockGetTimeError = 1,
GetNumberOfProcessorsError,
GetProcessTimesError,
GetSystemTimesError,
HostStatisticsError,
ProcStatError,
};
namespace detail {
template <>
struct UnusedZero<CPUUsageWatcherError> : UnusedZeroEnum<CPUUsageWatcherError> {
};
} // namespace detail
class CPUUsageHangAnnotator : public BackgroundHangAnnotator {
public:
};
class CPUUsageWatcher : public BackgroundHangAnnotator {
public:
#ifdef CPU_USAGE_WATCHER_ACTIVE
CPUUsageWatcher()
: mInitialized(false),
mExternalUsageThreshold(0),
mExternalUsageRatio(0),
mProcessUsageTime(0),
mProcessUpdateTime(0),
mGlobalUsageTime(0),
mGlobalUpdateTime(0),
mNumCPUs(0) {}
#endif
Result<Ok, CPUUsageWatcherError> Init();
void Uninit();
// Updates necessary values to allow AnnotateHang to function. This must be
// called on some semi-regular basis, as it will calculate the mean CPU
// usage values between now and the last time it was called.
Result<Ok, CPUUsageWatcherError> CollectCPUUsage();
void AnnotateHang(BackgroundHangAnnotations& aAnnotations) final;
private:
#ifdef CPU_USAGE_WATCHER_ACTIVE
bool mInitialized;
// The threshold above which we will mark a hang as occurring under high
// external CPU usage conditions
float mExternalUsageThreshold;
// The CPU usage (0-1) external to our process, averaged between the two
// most recent monitor thread runs
float mExternalUsageRatio;
// The total cumulative CPU usage time by our process as of the last
// CollectCPUUsage or Startup
uint64_t mProcessUsageTime;
// A time value in the same units as mProcessUsageTime used to
// determine the ratio of CPU usage time to idle time
uint64_t mProcessUpdateTime;
// The total cumulative CPU usage time by all processes as of the last
// CollectCPUUsage or Startup
uint64_t mGlobalUsageTime;
// A time value in the same units as mGlobalUsageTime used to
// determine the ratio of CPU usage time to idle time
uint64_t mGlobalUpdateTime;
// The number of virtual cores on our machine
uint64_t mNumCPUs;
#endif
};
} // namespace mozilla
#endif // mozilla_CPUUsageWatcher_h