Bug 1649056 - Pre-record some meta information before locking the profiler mutex - r=canaltinova

Some profile meta information can be gathered before the profiler mutex must be locked.
This reduces the main-thread locking when capturing.
Most importantly, it prevents deadlocking in case any of the data-gathering operation would itself rely on profiler-locking functions (e.g., starting a thread, which requires the lock to register the new thread with the profiler).

Differential Revision: https://phabricator.services.mozilla.com/D81491
This commit is contained in:
Gerald Squelart 2020-06-30 13:40:13 +00:00
Родитель 3de598d4a7
Коммит c1fe2ae51c
1 изменённых файлов: 141 добавлений и 66 удалений

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@ -2318,9 +2318,86 @@ static void StreamCategories(SpliceableJSONWriter& aWriter) {
#undef CATEGORY_JSON_END_CATEGORY
}
static void StreamMetaJSCustomObject(PSLockRef aLock,
SpliceableJSONWriter& aWriter,
bool aIsShuttingDown) {
// Some meta information that is better recorded before streaming the profile.
// This is *not* intended to be cached, as some values could change between
// profiling sessions.
struct PreRecordedMetaInformation {
bool mAsyncStacks;
// This struct should only live on the stack, so it's fine to use Auto
// strings.
nsAutoCString mHttpPlatform;
nsAutoCString mHttpOscpu;
nsAutoCString mHttpMisc;
nsAutoCString mRuntimeABI;
nsAutoCString mRuntimeToolkit;
nsAutoCString mAppInfoProduct;
nsAutoCString mAppInfoAppBuildID;
nsAutoCString mAppInfoSourceURL;
int32_t mProcessInfoCpuCount;
int32_t mProcessInfoCpuCores;
};
// This function should be called out of the profiler lock.
// It gathers non-trivial data that doesn't require the profiler to stop, or for
// which the request could theoretically deadlock if the profiler is locked.
static PreRecordedMetaInformation PreRecordMetaInformation() {
gPSMutex.AssertCurrentThreadDoesNotOwn();
PreRecordedMetaInformation info = {}; // Aggregate-init all fields.
if (!NS_IsMainThread()) {
// Leave these properties out if we're not on the main thread.
// At the moment, the only case in which this function is called on a
// background thread is if we're in a content process and are going to
// send this profile to the parent process. In that case, the parent
// process profile's "meta" object already has the rest of the properties,
// and the parent process profile is dumped on that process's main thread.
return info;
}
info.mAsyncStacks = Preferences::GetBool("javascript.options.asyncstack");
nsresult res;
if (nsCOMPtr<nsIHttpProtocolHandler> http =
do_GetService(NS_NETWORK_PROTOCOL_CONTRACTID_PREFIX "http", &res);
!NS_FAILED(res) && http) {
Unused << http->GetPlatform(info.mHttpPlatform);
Unused << http->GetOscpu(info.mHttpOscpu);
Unused << http->GetMisc(info.mHttpMisc);
}
if (nsCOMPtr<nsIXULRuntime> runtime =
do_GetService("@mozilla.org/xre/runtime;1");
runtime) {
Unused << runtime->GetXPCOMABI(info.mRuntimeABI);
Unused << runtime->GetWidgetToolkit(info.mRuntimeToolkit);
}
if (nsCOMPtr<nsIXULAppInfo> appInfo =
do_GetService("@mozilla.org/xre/app-info;1");
appInfo) {
Unused << appInfo->GetName(info.mAppInfoProduct);
Unused << appInfo->GetAppBuildID(info.mAppInfoAppBuildID);
Unused << appInfo->GetSourceURL(info.mAppInfoSourceURL);
}
ProcessInfo processInfo = {}; // Aggregate-init all fields to false/zeroes.
if (NS_SUCCEEDED(CollectProcessInfo(processInfo))) {
info.mProcessInfoCpuCount = processInfo.cpuCount;
info.mProcessInfoCpuCores = processInfo.cpuCores;
}
return info;
}
static void StreamMetaJSCustomObject(
PSLockRef aLock, SpliceableJSONWriter& aWriter, bool aIsShuttingDown,
const PreRecordedMetaInformation& aPreRecordedMetaInformation) {
MOZ_RELEASE_ASSERT(CorePS::Exists() && ActivePS::Exists(aLock));
aWriter.IntProperty("version", 19);
@ -2369,72 +2446,54 @@ static void StreamMetaJSCustomObject(PSLockRef aLock,
aWriter.IntProperty("gcpoison", JS::IsGCPoisoning() ? 1 : 0);
bool asyncStacks = Preferences::GetBool("javascript.options.asyncstack");
aWriter.IntProperty("asyncstack", asyncStacks);
aWriter.IntProperty("asyncstack", aPreRecordedMetaInformation.mAsyncStacks);
aWriter.IntProperty("processType", XRE_GetProcessType());
aWriter.StringProperty("updateChannel", MOZ_STRINGIFY(MOZ_UPDATE_CHANNEL));
nsresult res;
nsCOMPtr<nsIHttpProtocolHandler> http =
do_GetService(NS_NETWORK_PROTOCOL_CONTRACTID_PREFIX "http", &res);
if (!NS_FAILED(res)) {
nsAutoCString string;
res = http->GetPlatform(string);
if (!NS_FAILED(res)) {
aWriter.StringProperty("platform", string.Data());
}
res = http->GetOscpu(string);
if (!NS_FAILED(res)) {
aWriter.StringProperty("oscpu", string.Data());
}
res = http->GetMisc(string);
if (!NS_FAILED(res)) {
aWriter.StringProperty("misc", string.Data());
}
if (!aPreRecordedMetaInformation.mHttpPlatform.IsEmpty()) {
aWriter.StringProperty("platform",
aPreRecordedMetaInformation.mHttpPlatform.Data());
}
if (!aPreRecordedMetaInformation.mHttpOscpu.IsEmpty()) {
aWriter.StringProperty("oscpu",
aPreRecordedMetaInformation.mHttpOscpu.Data());
}
if (!aPreRecordedMetaInformation.mHttpMisc.IsEmpty()) {
aWriter.StringProperty("misc",
aPreRecordedMetaInformation.mHttpMisc.Data());
}
nsCOMPtr<nsIXULRuntime> runtime = do_GetService("@mozilla.org/xre/runtime;1");
if (runtime) {
nsAutoCString string;
res = runtime->GetXPCOMABI(string);
if (!NS_FAILED(res)) aWriter.StringProperty("abi", string.Data());
res = runtime->GetWidgetToolkit(string);
if (!NS_FAILED(res)) aWriter.StringProperty("toolkit", string.Data());
if (!aPreRecordedMetaInformation.mRuntimeABI.IsEmpty()) {
aWriter.StringProperty("abi",
aPreRecordedMetaInformation.mRuntimeABI.Data());
}
if (!aPreRecordedMetaInformation.mRuntimeToolkit.IsEmpty()) {
aWriter.StringProperty("toolkit",
aPreRecordedMetaInformation.mRuntimeToolkit.Data());
}
nsCOMPtr<nsIXULAppInfo> appInfo =
do_GetService("@mozilla.org/xre/app-info;1");
if (appInfo) {
nsAutoCString string;
res = appInfo->GetName(string);
if (!NS_FAILED(res)) aWriter.StringProperty("product", string.Data());
res = appInfo->GetAppBuildID(string);
if (!NS_FAILED(res)) aWriter.StringProperty("appBuildID", string.Data());
res = appInfo->GetSourceURL(string);
if (!NS_FAILED(res)) aWriter.StringProperty("sourceURL", string.Data());
if (!aPreRecordedMetaInformation.mAppInfoProduct.IsEmpty()) {
aWriter.StringProperty("product",
aPreRecordedMetaInformation.mAppInfoProduct.Data());
}
if (!aPreRecordedMetaInformation.mAppInfoAppBuildID.IsEmpty()) {
aWriter.StringProperty(
"appBuildID", aPreRecordedMetaInformation.mAppInfoAppBuildID.Data());
}
if (!aPreRecordedMetaInformation.mAppInfoSourceURL.IsEmpty()) {
aWriter.StringProperty(
"sourceURL", aPreRecordedMetaInformation.mAppInfoSourceURL.Data());
}
ProcessInfo processInfo;
processInfo.cpuCount = 0;
processInfo.cpuCores = 0;
if (NS_SUCCEEDED(CollectProcessInfo(processInfo))) {
if (processInfo.cpuCores > 0) {
aWriter.IntProperty("physicalCPUs", processInfo.cpuCores);
}
if (processInfo.cpuCount > 0) {
aWriter.IntProperty("logicalCPUs", processInfo.cpuCount);
}
if (aPreRecordedMetaInformation.mProcessInfoCpuCores > 0) {
aWriter.IntProperty("physicalCPUs",
aPreRecordedMetaInformation.mProcessInfoCpuCores);
}
if (aPreRecordedMetaInformation.mProcessInfoCpuCount > 0) {
aWriter.IntProperty("logicalCPUs",
aPreRecordedMetaInformation.mProcessInfoCpuCount);
}
// We should avoid collecting extension metadata for profiler while XPCOM is
@ -2614,6 +2673,7 @@ profiler_code_address_service_for_presymbolication() {
static void locked_profiler_stream_json_for_this_process(
PSLockRef aLock, SpliceableJSONWriter& aWriter, double aSinceTime,
const PreRecordedMetaInformation& aPreRecordedMetaInformation,
bool aIsShuttingDown, ProfilerCodeAddressService* aService) {
LOG("locked_profiler_stream_json_for_this_process");
@ -2639,7 +2699,10 @@ static void locked_profiler_stream_json_for_this_process(
// Put meta data
aWriter.StartObjectProperty("meta");
{ StreamMetaJSCustomObject(aLock, aWriter, aIsShuttingDown); }
{
StreamMetaJSCustomObject(aLock, aWriter, aIsShuttingDown,
aPreRecordedMetaInformation);
}
aWriter.EndObject();
// Put page data
@ -2743,6 +2806,8 @@ bool profiler_stream_json_for_this_process(
MOZ_RELEASE_ASSERT(CorePS::Exists());
const auto preRecordedMetaInformation = PreRecordMetaInformation();
PSAutoLock lock(gPSMutex);
if (!ActivePS::Exists(lock)) {
@ -2750,6 +2815,7 @@ bool profiler_stream_json_for_this_process(
}
locked_profiler_stream_json_for_this_process(lock, aWriter, aSinceTime,
preRecordedMetaInformation,
aIsShuttingDown, aService);
return true;
}
@ -3933,9 +3999,10 @@ void profiler_init(void* aStackTop) {
filters.length(), 0);
}
static void locked_profiler_save_profile_to_file(PSLockRef aLock,
const char* aFilename,
bool aIsShuttingDown);
static void locked_profiler_save_profile_to_file(
PSLockRef aLock, const char* aFilename,
const PreRecordedMetaInformation& aPreRecordedMetaInformation,
bool aIsShuttingDown);
static SamplerThread* locked_profiler_stop(PSLockRef aLock);
@ -3947,6 +4014,8 @@ void profiler_shutdown(IsFastShutdown aIsFastShutdown) {
MOZ_RELEASE_ASSERT(NS_IsMainThread());
MOZ_RELEASE_ASSERT(CorePS::Exists());
const auto preRecordedMetaInformation = PreRecordMetaInformation();
ProfilerParent::ProfilerWillStopIfStarted();
// If the profiler is active we must get a handle to the SamplerThread before
@ -3960,6 +4029,7 @@ void profiler_shutdown(IsFastShutdown aIsFastShutdown) {
const char* filename = getenv("MOZ_PROFILER_SHUTDOWN");
if (filename) {
locked_profiler_save_profile_to_file(lock, filename,
preRecordedMetaInformation,
/* aIsShuttingDown */ true);
}
if (aIsFastShutdown == IsFastShutdown::Yes) {
@ -4171,9 +4241,10 @@ Vector<nsCString> profiler_move_exit_profiles() {
return profiles;
}
static void locked_profiler_save_profile_to_file(PSLockRef aLock,
const char* aFilename,
bool aIsShuttingDown = false) {
static void locked_profiler_save_profile_to_file(
PSLockRef aLock, const char* aFilename,
const PreRecordedMetaInformation& aPreRecordedMetaInformation,
bool aIsShuttingDown = false) {
LOG("locked_profiler_save_profile_to_file(%s)", aFilename);
MOZ_RELEASE_ASSERT(CorePS::Exists() && ActivePS::Exists(aLock));
@ -4185,6 +4256,7 @@ static void locked_profiler_save_profile_to_file(PSLockRef aLock,
w.Start();
{
locked_profiler_stream_json_for_this_process(aLock, w, /* sinceTime */ 0,
aPreRecordedMetaInformation,
aIsShuttingDown, nullptr);
w.StartArrayProperty("processes");
@ -4207,13 +4279,16 @@ void profiler_save_profile_to_file(const char* aFilename) {
MOZ_RELEASE_ASSERT(CorePS::Exists());
const auto preRecordedMetaInformation = PreRecordMetaInformation();
PSAutoLock lock(gPSMutex);
if (!ActivePS::Exists(lock)) {
return;
}
locked_profiler_save_profile_to_file(lock, aFilename);
locked_profiler_save_profile_to_file(lock, aFilename,
preRecordedMetaInformation);
}
uint32_t profiler_get_available_features() {