gecko-dev/widget/android/ANRReporter.cpp
Gerald Squelart b13eeec2e9 Bug 1552063 - Use PowerOfTwo and PowerOfTwoMask in profilers - r=gregtatum
PowerOfTwo makes for a cleaner and more expressive interface, showing that the
profiler will use a power-of-2 storage size.

Using PowerOfTwoMask in ProfilerBuffer also makes it more obvious that we want
cheap modulo operations.
And we don't need to keep the original capacity, as it's only used once and can
easily be recomputed from the mask.

Differential Revision: https://phabricator.services.mozilla.com/D36027

--HG--
extra : moz-landing-system : lando
2019-06-28 07:12:57 +00:00

80 lines
2.4 KiB
C++

/* -*- Mode: c++; c-basic-offset: 2; tab-width: 20; indent-tabs-mode: nil; -*-
* 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/. */
#include "ANRReporter.h"
#include "GeckoProfiler.h"
#include <unistd.h>
namespace mozilla {
bool ANRReporter::RequestNativeStack(bool aUnwind) {
#ifdef MOZ_GECKO_PROFILER
if (profiler_is_active()) {
// Don't proceed if profiler is already running
return false;
}
// WARNING: we are on the ANR reporter thread at this point and it is
// generally unsafe to use the profiler from off the main thread. However,
// the risk here is limited because for most users, the profiler is not run
// elsewhere. See the discussion in Bug 863777, comment 13
uint32_t features = ProfilerFeature::Leaf | ProfilerFeature::Privacy |
(aUnwind ? ProfilerFeature::StackWalk : 0) |
ProfilerFeature::Threads;
const char* NATIVE_STACK_THREADS[] = {"GeckoMain", "Compositor"};
// Buffer one sample and let the profiler wait a long time
profiler_start(/* entries */ PowerOfTwo<uint32_t>(100), /* interval */ 10000,
features, NATIVE_STACK_THREADS,
sizeof(NATIVE_STACK_THREADS) / sizeof(char*));
#endif
return true;
}
jni::String::LocalRef ANRReporter::GetNativeStack() {
#ifdef MOZ_GECKO_PROFILER
// Timeout if we don't get a profiler sample after 5 seconds.
const PRIntervalTime timeout = PR_SecondsToInterval(5);
const PRIntervalTime startTime = PR_IntervalNow();
// Pointer to a profile JSON string
typedef mozilla::UniquePtr<char[]> ProfilePtr;
// profiler_get_profile() will return nullptr if the profiler is inactive.
ProfilePtr profile(profiler_get_profile());
if (!profile) {
return nullptr;
}
while (profile && !strstr(profile.get(), "\"samples\":[{")) {
// no sample yet?
if (PR_IntervalNow() - startTime >= timeout) {
return nullptr;
}
usleep(100000ul); // Sleep for 100ms
profile = ProfilePtr(profiler_get_profile());
}
if (profile) {
return jni::String::Param(profile.get());
}
#endif
return nullptr;
}
void ANRReporter::ReleaseNativeStack() {
#ifdef MOZ_GECKO_PROFILER
if (!profiler_is_active()) {
// Maybe profiler support is disabled?
return;
}
profiler_stop();
#endif
}
} // namespace mozilla