void mozilla_sampler_stop()
{
if (!stack_key_initialized)
mozilla_sampler_init();
TableTicker *t = tlsTicker.get();
if (!t) {
return;
}
bool disableJS = t->ProfileJS();
t->Stop();
delete t;
tlsTicker.set(NULL);
ProfileStack *stack = tlsStack.get();
ASSERT(stack != NULL);
if (disableJS)
stack->disableJSSampling();
nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
if (os)
os->NotifyObservers(nullptr, "profiler-stopped", nullptr);
}
// Values are only honored on the first start
void mozilla_sampler_start(int aProfileEntries, int aInterval,
const char** aFeatures, uint32_t aFeatureCount)
{
if (!stack_key_initialized)
mozilla_sampler_init();
ProfileStack *stack = tlsStack.get();
if (!stack) {
ASSERT(false);
return;
}
mozilla_sampler_stop();
TableTicker *t = new TableTicker(aInterval ? aInterval : PROFILE_DEFAULT_INTERVAL,
aProfileEntries ? aProfileEntries : PROFILE_DEFAULT_ENTRY,
stack, aFeatures, aFeatureCount);
tlsTicker.set(t);
t->Start();
if (t->ProfileJS())
stack->enableJSSampling();
nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
if (os)
os->NotifyObservers(nullptr, "profiler-started", nullptr);
}
void TableTicker::Tick(TickSample* sample)
{
// Marker(s) come before the sample
ProfileStack* stack = mPrimaryThreadProfile.GetStack();
for (int i = 0; stack->getMarker(i) != NULL; i++) {
mPrimaryThreadProfile.addTag(ProfileEntry('m', stack->getMarker(i)));
}
stack->mQueueClearMarker = true;
bool recordSample = true;
if (mJankOnly) {
// if we are on a different event we can discard any temporary samples
// we've kept around
if (sLastSampledEventGeneration != sCurrentEventGeneration) {
// XXX: we also probably want to add an entry to the profile to help
// distinguish which samples are part of the same event. That, or record
// the event generation in each sample
mPrimaryThreadProfile.erase();
}
sLastSampledEventGeneration = sCurrentEventGeneration;
recordSample = false;
// only record the events when we have a we haven't seen a tracer event for 100ms
if (!sLastTracerEvent.IsNull()) {
TimeDuration delta = sample->timestamp - sLastTracerEvent;
if (delta.ToMilliseconds() > 100.0) {
recordSample = true;
}
}
}
#if defined(USE_BACKTRACE) || defined(USE_NS_STACKWALK) || defined(USE_LIBUNWIND)
if (mUseStackWalk) {
doBacktrace(mPrimaryThreadProfile, sample);
} else {
doSampleStackTrace(stack, mPrimaryThreadProfile, sample);
}
#else
doSampleStackTrace(stack, mPrimaryThreadProfile, sample);
#endif
if (recordSample)
mPrimaryThreadProfile.flush();
if (!sLastTracerEvent.IsNull() && sample) {
TimeDuration delta = sample->timestamp - sLastTracerEvent;
mPrimaryThreadProfile.addTag(ProfileEntry('r', delta.ToMilliseconds()));
}
if (sample) {
TimeDuration delta = sample->timestamp - mStartTime;
mPrimaryThreadProfile.addTag(ProfileEntry('t', delta.ToMilliseconds()));
}
if (sLastFrameNumber != sFrameNumber) {
mPrimaryThreadProfile.addTag(ProfileEntry('f', sFrameNumber));
sLastFrameNumber = sFrameNumber;
}
}
void mozilla_sampler_stop()
{
if (!stack_key_initialized)
mozilla_sampler_init();
TableTicker *t = tlsTicker.get();
if (!t) {
return;
}
bool disableJS = t->ProfileJS();
t->Stop();
delete t;
tlsTicker.set(NULL);
ProfileStack *stack = tlsStack.get();
ASSERT(stack != NULL);
if (disableJS)
stack->disableJSSampling();
}
// Values are only honored on the first start
void mozilla_sampler_start(int aProfileEntries, int aInterval,
const char** aFeatures, uint32_t aFeatureCount)
{
if (!stack_key_initialized)
mozilla_sampler_init();
ProfileStack *stack = tlsStack.get();
if (!stack) {
ASSERT(false);
return;
}
mozilla_sampler_stop();
TableTicker *t = new TableTicker(aInterval, aProfileEntries, stack,
aFeatures, aFeatureCount);
tlsTicker.set(t);
t->Start();
if (t->ProfileJS())
stack->enableJSSampling();
}
void TableTicker::doBacktrace(ThreadProfile &aProfile, TickSample* aSample)
{
#ifndef XP_MACOSX
uintptr_t thread = GetThreadHandle(platform_data());
MOZ_ASSERT(thread);
#endif
void* pc_array[1000];
void* sp_array[1000];
PCArray array = {
pc_array,
sp_array,
mozilla::ArrayLength(pc_array),
0
};
// Start with the current function.
StackWalkCallback(aSample->pc, aSample->sp, &array);
#ifdef XP_MACOSX
pthread_t pt = GetProfiledThread(platform_data());
void *stackEnd = reinterpret_cast<void*>(-1);
if (pt)
stackEnd = static_cast<char*>(pthread_get_stackaddr_np(pt));
nsresult rv = FramePointerStackWalk(StackWalkCallback, 0, &array, reinterpret_cast<void**>(aSample->fp), stackEnd);
#else
nsresult rv = NS_StackWalk(StackWalkCallback, 0, &array, thread);
#endif
if (NS_SUCCEEDED(rv)) {
aProfile.addTag(ProfileEntry('s', "(root)"));
ProfileStack* stack = aProfile.GetStack();
int pseudoStackPos = 0;
/* We have two stacks, the native C stack we extracted from unwinding,
* and the pseudostack we managed during execution. We want to consolidate
* the two in order. We do so by merging using the approximate stack address
* when each entry was push. When pushing JS entry we may not now the stack
* address in which case we have a NULL stack address in which case we assume
* that it follows immediatly the previous element.
*
* C Stack | Address -- Pseudo Stack | Address
* main() | 0x100 run_js() | 0x40
* start() | 0x80 jsCanvas() | NULL
* timer() | 0x50 drawLine() | NULL
* azure() | 0x10
*
* Merged: main(), start(), timer(), run_js(), jsCanvas(), drawLine(), azure()
*/
// i is the index in C stack starting at main and decreasing
// pseudoStackPos is the position in the Pseudo stack starting
// at the first frame (run_js in the example) and increasing.
for (size_t i = array.count; i > 0; --i) {
while (pseudoStackPos < stack->stackSize()) {
volatile StackEntry& entry = stack->mStack[pseudoStackPos];
if (entry.stackAddress() < array.sp_array[i-1] && entry.stackAddress())
break;
addProfileEntry(entry, aProfile, stack, array.array[0]);
pseudoStackPos++;
}
aProfile.addTag(ProfileEntry('l', (void*)array.array[i-1]));
}
}
}
