fune/toolkit/components/telemetry/TelemetryHistogram.cpp
Alessio Placitelli 24270848ee Bug 1468809 - Do not snapshot expired keyed histograms. r=chutten,janerik
This patch changes the snapshotting code for keyed histograms
so that requesting a snapshot does not report expired histograms.

MozReview-Commit-ID: GDiw6yOcF8J

--HG--
extra : rebase_source : 30e10d7b1e63b6eef263066a49b8c4dea0c140e0
2018-06-15 19:31:26 +02:00

3187 lines
103 KiB
C++

/* -*- 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "jsapi.h"
#include "jsfriendapi.h"
#include "js/GCAPI.h"
#include "nsString.h"
#include "nsTHashtable.h"
#include "nsHashKeys.h"
#include "nsBaseHashtable.h"
#include "nsClassHashtable.h"
#include "nsITelemetry.h"
#include "nsPrintfCString.h"
#include "mozilla/dom/ToJSValue.h"
#include "mozilla/gfx/GPUProcessManager.h"
#include "mozilla/Atomics.h"
#include "mozilla/JSONWriter.h"
#include "mozilla/StartupTimeline.h"
#include "mozilla/StaticMutex.h"
#include "mozilla/Unused.h"
#include "TelemetryCommon.h"
#include "TelemetryHistogram.h"
#include "TelemetryScalar.h"
#include "ipc/TelemetryIPCAccumulator.h"
#include "base/histogram.h"
#include <limits>
using base::Histogram;
using base::BooleanHistogram;
using base::CountHistogram;
using base::FlagHistogram;
using base::LinearHistogram;
using mozilla::MakeTuple;
using mozilla::StaticMutex;
using mozilla::StaticMutexAutoLock;
using mozilla::Telemetry::HistogramAccumulation;
using mozilla::Telemetry::KeyedHistogramAccumulation;
using mozilla::Telemetry::HistogramID;
using mozilla::Telemetry::ProcessID;
using mozilla::Telemetry::HistogramCount;
using mozilla::Telemetry::Common::LogToBrowserConsole;
using mozilla::Telemetry::Common::RecordedProcessType;
using mozilla::Telemetry::Common::AutoHashtable;
using mozilla::Telemetry::Common::GetNameForProcessID;
using mozilla::Telemetry::Common::GetIDForProcessName;
using mozilla::Telemetry::Common::IsExpiredVersion;
using mozilla::Telemetry::Common::CanRecordDataset;
using mozilla::Telemetry::Common::CanRecordProduct;
using mozilla::Telemetry::Common::SupportedProduct;
using mozilla::Telemetry::Common::IsInDataset;
using mozilla::Telemetry::Common::ToJSString;
namespace TelemetryIPCAccumulator = mozilla::TelemetryIPCAccumulator;
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// Naming: there are two kinds of functions in this file:
//
// * Functions named internal_*: these can only be reached via an
// interface function (TelemetryHistogram::*). They mostly expect
// the interface function to have acquired
// |gTelemetryHistogramMutex|, so they do not have to be
// thread-safe. However, those internal_* functions that are
// reachable from internal_WrapAndReturnHistogram and
// internal_WrapAndReturnKeyedHistogram can sometimes be called
// without |gTelemetryHistogramMutex|, and so might be racey.
//
// * Functions named TelemetryHistogram::*. This is the external interface.
// Entries and exits to these functions are serialised using
// |gTelemetryHistogramMutex|, except for GetKeyedHistogramSnapshots and
// CreateHistogramSnapshots.
//
// Avoiding races and deadlocks:
//
// All functions in the external interface (TelemetryHistogram::*) are
// serialised using the mutex |gTelemetryHistogramMutex|. This means
// that the external interface is thread-safe, and many of the
// internal_* functions can ignore thread safety. But it also brings
// a danger of deadlock if any function in the external interface can
// get back to that interface. That is, we will deadlock on any call
// chain like this
//
// TelemetryHistogram::* -> .. any functions .. -> TelemetryHistogram::*
//
// To reduce the danger of that happening, observe the following rules:
//
// * No function in TelemetryHistogram::* may directly call, nor take the
// address of, any other function in TelemetryHistogram::*.
//
// * No internal function internal_* may call, nor take the address
// of, any function in TelemetryHistogram::*.
//
// internal_WrapAndReturnHistogram and
// internal_WrapAndReturnKeyedHistogram are not protected by
// |gTelemetryHistogramMutex| because they make calls to the JS
// engine, but that can in turn call back to Telemetry and hence back
// to a TelemetryHistogram:: function, in order to report GC and other
// statistics. This would lead to deadlock due to attempted double
// acquisition of |gTelemetryHistogramMutex|, if the internal_* functions
// were required to be protected by |gTelemetryHistogramMutex|. To
// break that cycle, we relax that requirement. Unfortunately this
// means that this file is not guaranteed race-free.
// This is a StaticMutex rather than a plain Mutex (1) so that
// it gets initialised in a thread-safe manner the first time
// it is used, and (2) because it is never de-initialised, and
// a normal Mutex would show up as a leak in BloatView. StaticMutex
// also has the "OffTheBooks" property, so it won't show as a leak
// in BloatView.
static StaticMutex gTelemetryHistogramMutex;
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE TYPES
namespace {
typedef nsDataHashtable<nsCStringHashKey, HistogramID> StringToHistogramIdMap;
// Hardcoded probes
struct HistogramInfo {
uint32_t min;
uint32_t max;
uint32_t bucketCount;
uint32_t histogramType;
uint32_t name_offset;
uint32_t expiration_offset;
uint32_t dataset;
uint32_t label_index;
uint32_t label_count;
uint32_t key_index;
uint32_t key_count;
RecordedProcessType record_in_processes;
bool keyed;
SupportedProduct products;
const char *name() const;
const char *expiration() const;
nsresult label_id(const char* label, uint32_t* labelId) const;
bool allows_key(const nsACString& key) const;
};
// Structs used to keep information about the histograms for which a
// snapshot should be created.
struct HistogramSnapshotData {
nsTArray<Histogram::Sample> mBucketRanges;
nsTArray<Histogram::Count> mBucketCounts;
int64_t mSampleSum; // Same type as Histogram::SampleSet::sum_
};
struct HistogramSnapshotInfo {
HistogramSnapshotData data;
HistogramID histogramID;
};
typedef mozilla::Vector<HistogramSnapshotInfo> HistogramSnapshotsArray;
typedef mozilla::Vector<HistogramSnapshotsArray> HistogramProcessSnapshotsArray;
// The following is used to handle snapshot information for keyed histograms.
typedef nsDataHashtable<nsCStringHashKey, HistogramSnapshotData> KeyedHistogramSnapshotData;
struct KeyedHistogramSnapshotInfo {
KeyedHistogramSnapshotData data;
HistogramID histogramId;
};
typedef mozilla::Vector<KeyedHistogramSnapshotInfo> KeyedHistogramSnapshotsArray;
typedef mozilla::Vector<KeyedHistogramSnapshotsArray> KeyedHistogramProcessSnapshotsArray;
class KeyedHistogram {
public:
KeyedHistogram(HistogramID id, const HistogramInfo& info, bool expired);
~KeyedHistogram();
nsresult GetHistogram(const nsCString& name, Histogram** histogram);
Histogram* GetHistogram(const nsCString& name);
uint32_t GetHistogramType() const { return mHistogramInfo.histogramType; }
nsresult GetJSKeys(JSContext* cx, JS::CallArgs& args);
// Note: unlike other methods, GetJSSnapshot is thread safe.
nsresult GetJSSnapshot(JSContext* cx, JS::Handle<JSObject*> obj,
bool clearSubsession);
nsresult GetSnapshot(const StaticMutexAutoLock& aLock,
KeyedHistogramSnapshotData& aSnapshot, bool aClearSubsession);
nsresult Add(const nsCString& key, uint32_t aSample, ProcessID aProcessType);
void Clear();
HistogramID GetHistogramID() const { return mId; }
bool IsEmpty() const { return mHistogramMap.IsEmpty(); }
bool IsExpired() const { return mIsExpired; }
private:
typedef nsBaseHashtableET<nsCStringHashKey, Histogram*> KeyedHistogramEntry;
typedef AutoHashtable<KeyedHistogramEntry> KeyedHistogramMapType;
KeyedHistogramMapType mHistogramMap;
const HistogramID mId;
const HistogramInfo& mHistogramInfo;
bool mIsExpired;
};
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE STATE, SHARED BY ALL THREADS
namespace {
// Set to true once this global state has been initialized
bool gInitDone = false;
// Whether we are collecting the base, opt-out, Histogram data.
bool gCanRecordBase = false;
// Whether we are collecting the extended, opt-in, Histogram data.
bool gCanRecordExtended = false;
// The storage for actual Histogram instances.
// We use separate ones for plain and keyed histograms.
Histogram** gHistogramStorage;
// Keyed histograms internally map string keys to individual Histogram instances.
KeyedHistogram** gKeyedHistogramStorage;
// Cache of histogram name to a histogram id.
StringToHistogramIdMap gNameToHistogramIDMap(HistogramCount);
// To simplify logic below we use a single histogram instance for all expired histograms.
Histogram* gExpiredHistogram = nullptr;
// The single placeholder for expired keyed histograms.
KeyedHistogram* gExpiredKeyedHistogram = nullptr;
// This tracks whether recording is enabled for specific histograms.
// To utilize C++ initialization rules, we invert the meaning to "disabled".
bool gHistogramRecordingDisabled[HistogramCount] = {};
// This is for gHistogramInfos, gHistogramStringTable
#include "TelemetryHistogramData.inc"
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE CONSTANTS
namespace {
// List of histogram IDs which should have recording disabled initially.
const HistogramID kRecordingInitiallyDisabledIDs[] = {
mozilla::Telemetry::FX_REFRESH_DRIVER_SYNC_SCROLL_FRAME_DELAY_MS,
// The array must not be empty. Leave these item here.
mozilla::Telemetry::TELEMETRY_TEST_COUNT_INIT_NO_RECORD,
mozilla::Telemetry::TELEMETRY_TEST_KEYED_COUNT_INIT_NO_RECORD
};
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// The core storage access functions.
// They wrap access to the histogram storage and lookup caches.
namespace {
size_t internal_KeyedHistogramStorageIndex(HistogramID aHistogramId,
ProcessID aProcessId)
{
return aHistogramId * size_t(ProcessID::Count) + size_t(aProcessId);
}
size_t internal_HistogramStorageIndex(const StaticMutexAutoLock& aLock,
HistogramID aHistogramId,
ProcessID aProcessId)
{
static_assert(
HistogramCount <
std::numeric_limits<size_t>::max() / size_t(ProcessID::Count),
"Too many histograms and processes to store in a 1D array.");
return aHistogramId * size_t(ProcessID::Count) + size_t(aProcessId);
}
Histogram* internal_GetHistogramFromStorage(const StaticMutexAutoLock& aLock,
HistogramID aHistogramId,
ProcessID aProcessId)
{
size_t index = internal_HistogramStorageIndex(aLock, aHistogramId, aProcessId);
return gHistogramStorage[index];
}
void internal_SetHistogramInStorage(const StaticMutexAutoLock& aLock,
HistogramID aHistogramId,
ProcessID aProcessId,
Histogram* aHistogram)
{
MOZ_ASSERT(XRE_IsParentProcess(),
"Histograms are stored only in the parent process.");
size_t index = internal_HistogramStorageIndex(aLock, aHistogramId, aProcessId);
MOZ_ASSERT(!gHistogramStorage[index],
"Mustn't overwrite storage without clearing it first.");
gHistogramStorage[index] = aHistogram;
}
KeyedHistogram* internal_GetKeyedHistogramFromStorage(HistogramID aHistogramId,
ProcessID aProcessId)
{
size_t index = internal_KeyedHistogramStorageIndex(aHistogramId, aProcessId);
return gKeyedHistogramStorage[index];
}
void internal_SetKeyedHistogramInStorage(HistogramID aHistogramId,
ProcessID aProcessId,
KeyedHistogram* aKeyedHistogram)
{
MOZ_ASSERT(XRE_IsParentProcess(),
"Keyed Histograms are stored only in the parent process.");
size_t index = internal_KeyedHistogramStorageIndex(aHistogramId, aProcessId);
MOZ_ASSERT(!gKeyedHistogramStorage[index],
"Mustn't overwrite storage without clearing it first");
gKeyedHistogramStorage[index] = aKeyedHistogram;
}
// Factory function for histogram instances.
Histogram*
internal_CreateHistogramInstance(const HistogramInfo& info, int bucketsOffset);
bool
internal_IsHistogramEnumId(HistogramID aID)
{
static_assert(((HistogramID)-1 > 0), "ID should be unsigned.");
return aID < HistogramCount;
}
// Look up a plain histogram by id.
Histogram*
internal_GetHistogramById(const StaticMutexAutoLock& aLock,
HistogramID histogramId,
ProcessID processId,
bool instantiate = true)
{
MOZ_ASSERT(internal_IsHistogramEnumId(histogramId));
MOZ_ASSERT(!gHistogramInfos[histogramId].keyed);
MOZ_ASSERT(processId < ProcessID::Count);
Histogram* h = internal_GetHistogramFromStorage(aLock, histogramId, processId);
if (h || !instantiate) {
return h;
}
const HistogramInfo& info = gHistogramInfos[histogramId];
const int bucketsOffset = gHistogramBucketLowerBoundIndex[histogramId];
h = internal_CreateHistogramInstance(info, bucketsOffset);
MOZ_ASSERT(h);
internal_SetHistogramInStorage(aLock, histogramId, processId, h);
return h;
}
// Look up a keyed histogram by id.
KeyedHistogram*
internal_GetKeyedHistogramById(HistogramID histogramId, ProcessID processId,
bool instantiate = true)
{
MOZ_ASSERT(internal_IsHistogramEnumId(histogramId));
MOZ_ASSERT(gHistogramInfos[histogramId].keyed);
MOZ_ASSERT(processId < ProcessID::Count);
KeyedHistogram* kh = internal_GetKeyedHistogramFromStorage(histogramId,
processId);
if (kh || !instantiate) {
return kh;
}
const HistogramInfo& info = gHistogramInfos[histogramId];
const bool isExpired = IsExpiredVersion(info.expiration());
// If the keyed histogram is expired, set its storage to the expired
// keyed histogram.
if (isExpired) {
if (!gExpiredKeyedHistogram) {
// If we don't have an expired keyed histogram, create one.
gExpiredKeyedHistogram = new KeyedHistogram(histogramId, info, true /* expired */);
MOZ_ASSERT(gExpiredKeyedHistogram);
}
kh = gExpiredKeyedHistogram;
} else {
kh = new KeyedHistogram(histogramId, info, false /* expired */);
}
internal_SetKeyedHistogramInStorage(histogramId, processId, kh);
return kh;
}
// Look up a histogram id from a histogram name.
nsresult
internal_GetHistogramIdByName(const StaticMutexAutoLock& aLock,
const nsACString& name,
HistogramID* id)
{
const bool found = gNameToHistogramIDMap.Get(name, id);
if (!found) {
return NS_ERROR_ILLEGAL_VALUE;
}
return NS_OK;
}
// Clear a histogram from storage.
void
internal_ClearHistogramById(const StaticMutexAutoLock& aLock,
HistogramID histogramId,
ProcessID processId)
{
size_t index = internal_HistogramStorageIndex(aLock, histogramId, processId);
if (gHistogramStorage[index] == gExpiredHistogram) {
// We keep gExpiredHistogram until TelemetryHistogram::DeInitializeGlobalState
return;
}
delete gHistogramStorage[index];
gHistogramStorage[index] = nullptr;
}
}
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE: Misc small helpers
namespace {
bool
internal_CanRecordBase() {
return gCanRecordBase;
}
bool
internal_CanRecordExtended() {
return gCanRecordExtended;
}
bool
internal_AttemptedGPUProcess() {
// Check if it was tried to launch a process.
bool attemptedGPUProcess = false;
if (auto gpm = mozilla::gfx::GPUProcessManager::Get()) {
attemptedGPUProcess = gpm->AttemptedGPUProcess();
}
return attemptedGPUProcess;
}
// Note: this is completely unrelated to mozilla::IsEmpty.
bool
internal_IsEmpty(const StaticMutexAutoLock& aLock, const Histogram *h)
{
return h->is_empty();
}
bool
internal_IsExpired(const StaticMutexAutoLock& aLock, Histogram* h)
{
return h == gExpiredHistogram;
}
void
internal_SetHistogramRecordingEnabled(const StaticMutexAutoLock& aLock,
HistogramID id,
bool aEnabled)
{
MOZ_ASSERT(internal_IsHistogramEnumId(id));
gHistogramRecordingDisabled[id] = !aEnabled;
}
bool
internal_IsRecordingEnabled(HistogramID id)
{
MOZ_ASSERT(internal_IsHistogramEnumId(id));
return !gHistogramRecordingDisabled[id];
}
const char *
HistogramInfo::name() const
{
return &gHistogramStringTable[this->name_offset];
}
const char *
HistogramInfo::expiration() const
{
return &gHistogramStringTable[this->expiration_offset];
}
nsresult
HistogramInfo::label_id(const char* label, uint32_t* labelId) const
{
MOZ_ASSERT(label);
MOZ_ASSERT(this->histogramType == nsITelemetry::HISTOGRAM_CATEGORICAL);
if (this->histogramType != nsITelemetry::HISTOGRAM_CATEGORICAL) {
return NS_ERROR_FAILURE;
}
for (uint32_t i = 0; i < this->label_count; ++i) {
// gHistogramLabelTable contains the indices of the label strings in the
// gHistogramStringTable.
// They are stored in-order and consecutively, from the offset label_index
// to (label_index + label_count).
uint32_t string_offset = gHistogramLabelTable[this->label_index + i];
const char* const str = &gHistogramStringTable[string_offset];
if (::strcmp(label, str) == 0) {
*labelId = i;
return NS_OK;
}
}
return NS_ERROR_FAILURE;
}
bool
HistogramInfo::allows_key(const nsACString& key) const
{
MOZ_ASSERT(this->keyed);
// If we didn't specify a list of allowed keys, just return true.
if (this->key_count == 0) {
return true;
}
// Otherwise, check if |key| is in the list of allowed keys.
for (uint32_t i = 0; i < this->key_count; ++i) {
// gHistogramKeyTable contains the indices of the key strings in the
// gHistogramStringTable. They are stored in-order and consecutively,
// from the offset key_index to (key_index + key_count).
uint32_t string_offset = gHistogramKeyTable[this->key_index + i];
const char* const str = &gHistogramStringTable[string_offset];
if (key.EqualsASCII(str)) {
return true;
}
}
// |key| was not found.
return false;
}
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE: Histogram Get, Add, Clone, Clear functions
namespace {
nsresult
internal_CheckHistogramArguments(const HistogramInfo& info)
{
if (info.histogramType != nsITelemetry::HISTOGRAM_BOOLEAN
&& info.histogramType != nsITelemetry::HISTOGRAM_FLAG
&& info.histogramType != nsITelemetry::HISTOGRAM_COUNT) {
// Sanity checks for histogram parameters.
if (info.min >= info.max) {
return NS_ERROR_ILLEGAL_VALUE;
}
if (info.bucketCount <= 2) {
return NS_ERROR_ILLEGAL_VALUE;
}
if (info.min < 1) {
return NS_ERROR_ILLEGAL_VALUE;
}
}
return NS_OK;
}
Histogram*
internal_CreateHistogramInstance(const HistogramInfo& passedInfo, int bucketsOffset)
{
if (NS_FAILED(internal_CheckHistogramArguments(passedInfo))) {
MOZ_ASSERT(false, "Failed histogram argument checks.");
return nullptr;
}
// To keep the code simple we map all the calls to expired histograms to the same histogram instance.
// We create that instance lazily when needed.
const bool isExpired = IsExpiredVersion(passedInfo.expiration());
HistogramInfo info = passedInfo;
const int* buckets = &gHistogramBucketLowerBounds[bucketsOffset];
if (isExpired) {
if (gExpiredHistogram) {
return gExpiredHistogram;
}
// The first values in gHistogramBucketLowerBounds are reserved for
// expired histograms.
buckets = gHistogramBucketLowerBounds;
info.min = 1;
info.max = 2;
info.bucketCount = 3;
info.histogramType = nsITelemetry::HISTOGRAM_LINEAR;
}
Histogram::Flags flags = Histogram::kNoFlags;
Histogram* h = nullptr;
switch (info.histogramType) {
case nsITelemetry::HISTOGRAM_EXPONENTIAL:
h = Histogram::FactoryGet(info.min, info.max, info.bucketCount, flags, buckets);
break;
case nsITelemetry::HISTOGRAM_LINEAR:
case nsITelemetry::HISTOGRAM_CATEGORICAL:
h = LinearHistogram::FactoryGet(info.min, info.max, info.bucketCount, flags, buckets);
break;
case nsITelemetry::HISTOGRAM_BOOLEAN:
h = BooleanHistogram::FactoryGet(flags, buckets);
break;
case nsITelemetry::HISTOGRAM_FLAG:
h = FlagHistogram::FactoryGet(flags, buckets);
break;
case nsITelemetry::HISTOGRAM_COUNT:
h = CountHistogram::FactoryGet(flags, buckets);
break;
default:
MOZ_ASSERT(false, "Invalid histogram type");
return nullptr;
}
if (isExpired) {
gExpiredHistogram = h;
}
return h;
}
nsresult
internal_HistogramAdd(const StaticMutexAutoLock& aLock,
Histogram& histogram,
const HistogramID id,
uint32_t value,
ProcessID aProcessType)
{
// Check if we are allowed to record the data.
bool canRecordDataset = CanRecordDataset(gHistogramInfos[id].dataset,
internal_CanRecordBase(),
internal_CanRecordExtended());
// If `histogram` is a non-parent-process histogram, then recording-enabled
// has been checked in its owner process.
if (!canRecordDataset ||
(aProcessType == ProcessID::Parent && !internal_IsRecordingEnabled(id))) {
return NS_OK;
}
// Don't record if the current platform is not enabled
if (!CanRecordProduct(gHistogramInfos[id].products)) {
return NS_OK;
}
// The internal representation of a base::Histogram's buckets uses `int`.
// Clamp large values of `value` to be INT_MAX so they continue to be treated
// as large values (instead of negative ones).
if (value > INT_MAX) {
TelemetryScalar::Add(
mozilla::Telemetry::ScalarID::TELEMETRY_ACCUMULATE_CLAMPED_VALUES,
NS_ConvertASCIItoUTF16(gHistogramInfos[id].name()), 1);
value = INT_MAX;
}
histogram.Add(value);
return NS_OK;
}
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE: Histogram reflection helpers
namespace {
/**
* Copy histograms and samples to Mozilla-friendly structures.
* Please note that this version does not make use of JS contexts.
*
* @param {StaticMutexAutoLock} the proof we hold the mutex.
* @param {Histogram} the histogram to reflect.
* @return {nsresult} NS_ERROR_FAILURE if we fail to allocate memory for the snapshot.
*/
nsresult
internal_GetHistogramAndSamples(const StaticMutexAutoLock& aLock,
const Histogram *h,
HistogramSnapshotData& aSnapshot)
{
MOZ_ASSERT(h);
// Convert the ranges of the buckets to a nsTArray.
const size_t bucketCount = h->bucket_count();
for (size_t i = 0; i < bucketCount; i++) {
if (!aSnapshot.mBucketRanges.AppendElement(h->ranges(i))) {
return NS_ERROR_FAILURE;
}
}
// Get a snapshot of the samples.
Histogram::SampleSet ss;
h->SnapshotSample(&ss);
// Get the number of samples in each bucket.
for (size_t i = 0; i < bucketCount; i++) {
if (!aSnapshot.mBucketCounts.AppendElement(ss.counts(i))) {
return NS_ERROR_FAILURE;
}
}
// Finally, save the |sum|. We don't need to reflect declared_min, declared_max and
// histogram_type as they are in gHistogramInfo.
aSnapshot.mSampleSum = ss.sum();
return NS_OK;
}
nsresult
internal_ReflectHistogramAndSamples(JSContext *cx,
JS::Handle<JSObject*> obj,
const HistogramInfo& aHistogramInfo,
const HistogramSnapshotData& aSnapshot)
{
if (!(JS_DefineProperty(cx, obj, "min",
aHistogramInfo.min, JSPROP_ENUMERATE)
&& JS_DefineProperty(cx, obj, "max",
aHistogramInfo.max, JSPROP_ENUMERATE)
&& JS_DefineProperty(cx, obj, "histogram_type",
aHistogramInfo.histogramType, JSPROP_ENUMERATE)
&& JS_DefineProperty(cx, obj, "sum",
double(aSnapshot.mSampleSum), JSPROP_ENUMERATE))) {
return NS_ERROR_FAILURE;
}
// Don't rely on the bucket counts from "aHistogramInfo": it may
// differ from the length of aSnapshot.mBucketCounts due to expired
// histograms.
const size_t count = aSnapshot.mBucketCounts.Length();
MOZ_ASSERT(count == aSnapshot.mBucketRanges.Length(),
"The number of buckets and the number of counts must match.");
// Create the "ranges" property and add it to the final object.
JS::Rooted<JSObject*> rarray(cx, JS_NewArrayObject(cx, count));
if (!rarray
|| !JS_DefineProperty(cx, obj, "ranges", rarray, JSPROP_ENUMERATE)) {
return NS_ERROR_FAILURE;
}
// Fill the "ranges" property.
for (size_t i = 0; i < count; i++) {
if (!JS_DefineElement(cx, rarray, i, aSnapshot.mBucketRanges[i], JSPROP_ENUMERATE)) {
return NS_ERROR_FAILURE;
}
}
JS::Rooted<JSObject*> counts_array(cx, JS_NewArrayObject(cx, count));
if (!counts_array
|| !JS_DefineProperty(cx, obj, "counts", counts_array, JSPROP_ENUMERATE)) {
return NS_ERROR_FAILURE;
}
// Fill the "counts" property.
for (size_t i = 0; i < count; i++) {
if (!JS_DefineElement(cx, counts_array, i, aSnapshot.mBucketCounts[i], JSPROP_ENUMERATE)) {
return NS_ERROR_FAILURE;
}
}
return NS_OK;
}
bool
internal_ShouldReflectHistogram(const StaticMutexAutoLock& aLock, Histogram* h, HistogramID id)
{
// Only flag histograms are serialized when they are empty.
// This has historical reasons, changing this will require downstream changes.
// The cheaper path here is to just deprecate flag histograms in favor
// of scalars.
uint32_t type = gHistogramInfos[id].histogramType;
if (internal_IsEmpty(aLock, h) && type != nsITelemetry::HISTOGRAM_FLAG) {
return false;
}
// Don't reflect the histogram if it's not allowed in this product.
if (!CanRecordProduct(gHistogramInfos[id].products)) {
return false;
}
return true;
}
/**
* Helper function to get a snapshot of the histograms.
*
* @param {aLock} the lock proof.
* @param {aDataset} the dataset for which the snapshot is being requested.
* @param {aClearSubsession} whether or not to clear the data after
* taking the snapshot.
* @param {aIncludeGPU} whether or not to include data for the GPU.
* @param {aOutSnapshot} the container in which the snapshot data will be stored.
* @return {nsresult} NS_OK if the snapshot was successfully taken or
* NS_ERROR_OUT_OF_MEMORY if it failed to allocate memory.
*/
nsresult
internal_GetHistogramsSnapshot(const StaticMutexAutoLock& aLock,
unsigned int aDataset,
bool aClearSubsession,
bool aIncludeGPU,
HistogramProcessSnapshotsArray& aOutSnapshot)
{
if (!aOutSnapshot.resize(static_cast<uint32_t>(ProcessID::Count))) {
return NS_ERROR_OUT_OF_MEMORY;
}
for (uint32_t process = 0; process < static_cast<uint32_t>(ProcessID::Count); ++process) {
HistogramSnapshotsArray& hArray = aOutSnapshot[process];
for (size_t i = 0; i < HistogramCount; ++i) {
const HistogramInfo& info = gHistogramInfos[i];
if (info.keyed) {
continue;
}
HistogramID id = HistogramID(i);
if (!CanRecordInProcess(info.record_in_processes, ProcessID(process)) ||
((ProcessID(process) == ProcessID::Gpu) && !aIncludeGPU)) {
continue;
}
if (!IsInDataset(info.dataset, aDataset)) {
continue;
}
bool shouldInstantiate =
info.histogramType == nsITelemetry::HISTOGRAM_FLAG;
Histogram* h = internal_GetHistogramById(aLock, id, ProcessID(process),
shouldInstantiate);
if (!h || internal_IsExpired(aLock, h) || !internal_ShouldReflectHistogram(aLock, h, id)) {
continue;
}
HistogramSnapshotData snapshotData;
if (NS_FAILED(internal_GetHistogramAndSamples(aLock, h, snapshotData))) {
continue;
}
if (!hArray.emplaceBack(HistogramSnapshotInfo{snapshotData, id})) {
return NS_ERROR_OUT_OF_MEMORY;
}
if (aClearSubsession) {
h->Clear();
}
}
}
return NS_OK;
}
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE: class KeyedHistogram and internal_ReflectKeyedHistogram
namespace {
nsresult
internal_ReflectKeyedHistogram(const KeyedHistogramSnapshotData& aSnapshot,
const HistogramInfo& info,
JSContext* aCx, JS::Handle<JSObject*> aObj)
{
for (auto iter = aSnapshot.ConstIter(); !iter.Done(); iter.Next()) {
HistogramSnapshotData& keyData = iter.Data();
JS::RootedObject histogramSnapshot(aCx, JS_NewPlainObject(aCx));
if (!histogramSnapshot) {
return NS_ERROR_FAILURE;
}
if (NS_FAILED(internal_ReflectHistogramAndSamples(aCx, histogramSnapshot,
info,
keyData))) {
return NS_ERROR_FAILURE;
}
const NS_ConvertUTF8toUTF16 key(iter.Key());
if (!JS_DefineUCProperty(aCx, aObj, key.Data(), key.Length(),
histogramSnapshot, JSPROP_ENUMERATE)) {
return NS_ERROR_FAILURE;
}
}
return NS_OK;
}
KeyedHistogram::KeyedHistogram(HistogramID id, const HistogramInfo& info, bool expired)
: mHistogramMap()
, mId(id)
, mHistogramInfo(info)
, mIsExpired(expired)
{
}
KeyedHistogram::~KeyedHistogram()
{
for (auto iter = mHistogramMap.Iter(); !iter.Done(); iter.Next()) {
Histogram* h = iter.Get()->mData;
if (h == gExpiredHistogram) {
continue;
}
delete h;
}
mHistogramMap.Clear();
}
nsresult
KeyedHistogram::GetHistogram(const nsCString& key, Histogram** histogram)
{
KeyedHistogramEntry* entry = mHistogramMap.GetEntry(key);
if (entry) {
*histogram = entry->mData;
return NS_OK;
}
int bucketsOffset = gHistogramBucketLowerBoundIndex[mId];
Histogram* h = internal_CreateHistogramInstance(mHistogramInfo, bucketsOffset);
if (!h) {
return NS_ERROR_FAILURE;
}
h->ClearFlags(Histogram::kUmaTargetedHistogramFlag);
*histogram = h;
entry = mHistogramMap.PutEntry(key);
if (MOZ_UNLIKELY(!entry)) {
return NS_ERROR_OUT_OF_MEMORY;
}
entry->mData = h;
return NS_OK;
}
Histogram*
KeyedHistogram::GetHistogram(const nsCString& key)
{
Histogram* h = nullptr;
if (NS_FAILED(GetHistogram(key, &h))) {
return nullptr;
}
return h;
}
nsresult
KeyedHistogram::Add(const nsCString& key, uint32_t sample,
ProcessID aProcessType)
{
bool canRecordDataset = CanRecordDataset(mHistogramInfo.dataset,
internal_CanRecordBase(),
internal_CanRecordExtended());
// If `histogram` is a non-parent-process histogram, then recording-enabled
// has been checked in its owner process.
if (!canRecordDataset ||
(aProcessType == ProcessID::Parent && !internal_IsRecordingEnabled(mId))) {
return NS_OK;
}
// Don't record if expired.
if (IsExpired()) {
return NS_OK;
}
// Don't record if the current platform is not enabled
if (!CanRecordProduct(gHistogramInfos[mId].products)) {
return NS_OK;
}
Histogram* histogram = GetHistogram(key);
MOZ_ASSERT(histogram);
if (!histogram) {
return NS_ERROR_FAILURE;
}
// The internal representation of a base::Histogram's buckets uses `int`.
// Clamp large values of `sample` to be INT_MAX so they continue to be treated
// as large values (instead of negative ones).
if (sample > INT_MAX) {
TelemetryScalar::Add(
mozilla::Telemetry::ScalarID::TELEMETRY_ACCUMULATE_CLAMPED_VALUES,
NS_ConvertASCIItoUTF16(mHistogramInfo.name()), 1);
sample = INT_MAX;
}
histogram->Add(sample);
return NS_OK;
}
void
KeyedHistogram::Clear()
{
MOZ_ASSERT(XRE_IsParentProcess());
if (!XRE_IsParentProcess()) {
return;
}
for (auto iter = mHistogramMap.Iter(); !iter.Done(); iter.Next()) {
Histogram* h = iter.Get()->mData;
if (h == gExpiredHistogram) {
continue;
}
delete h;
}
mHistogramMap.Clear();
}
nsresult
KeyedHistogram::GetJSKeys(JSContext* cx, JS::CallArgs& args)
{
JS::AutoValueVector keys(cx);
if (!keys.reserve(mHistogramMap.Count())) {
return NS_ERROR_OUT_OF_MEMORY;
}
for (auto iter = mHistogramMap.Iter(); !iter.Done(); iter.Next()) {
JS::RootedValue jsKey(cx);
jsKey.setString(ToJSString(cx, iter.Get()->GetKey()));
if (!keys.append(jsKey)) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
JS::RootedObject jsKeys(cx, JS_NewArrayObject(cx, keys));
if (!jsKeys) {
return NS_ERROR_FAILURE;
}
args.rval().setObject(*jsKeys);
return NS_OK;
}
nsresult
KeyedHistogram::GetJSSnapshot(JSContext* cx, JS::Handle<JSObject*> obj, bool clearSubsession)
{
// Get a snapshot of the data.
KeyedHistogramSnapshotData dataSnapshot;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
MOZ_ASSERT(internal_IsHistogramEnumId(mId));
// Take a snapshot of the data here, protected by the lock, and then,
// outside of the lock protection, mirror it to a JS structure.
if (NS_FAILED(GetSnapshot(locker, dataSnapshot, clearSubsession))) {
return NS_ERROR_FAILURE;
}
}
// Now that we have a copy of the data, mirror it to JS.
return internal_ReflectKeyedHistogram(dataSnapshot, gHistogramInfos[mId], cx, obj);
}
nsresult
KeyedHistogram::GetSnapshot(const StaticMutexAutoLock& aLock,
KeyedHistogramSnapshotData& aSnapshot, bool aClearSubsession)
{
// Snapshot every key.
for (auto iter = mHistogramMap.ConstIter(); !iter.Done(); iter.Next()) {
Histogram* keyData = iter.Get()->mData;
if (!keyData) {
return NS_ERROR_FAILURE;
}
HistogramSnapshotData keySnapshot;
if (NS_FAILED(internal_GetHistogramAndSamples(aLock, keyData, keySnapshot))) {
return NS_ERROR_FAILURE;
}
// Append to the final snapshot.
aSnapshot.Put(iter.Get()->GetKey(), std::move(keySnapshot));
}
if (aClearSubsession) {
Clear();
}
return NS_OK;
}
/**
* Helper function to get a snapshot of the keyed histograms.
*
* @param {aLock} the lock proof.
* @param {aDataset} the dataset for which the snapshot is being requested.
* @param {aClearSubsession} whether or not to clear the data after
* taking the snapshot.
* @param {aIncludeGPU} whether or not to include data for the GPU.
* @param {aOutSnapshot} the container in which the snapshot data will be stored.
* @param {aSkipEmpty} whether or not to skip empty keyed histograms from the
* snapshot. Can't always assume "true" for consistency with the other
* callers.
* @return {nsresult} NS_OK if the snapshot was successfully taken or
* NS_ERROR_OUT_OF_MEMORY if it failed to allocate memory.
*/
nsresult
internal_GetKeyedHistogramsSnapshot(const StaticMutexAutoLock& aLock,
unsigned int aDataset,
bool aClearSubsession,
bool aIncludeGPU,
KeyedHistogramProcessSnapshotsArray& aOutSnapshot,
bool aSkipEmpty = false)
{
if (!aOutSnapshot.resize(static_cast<uint32_t>(ProcessID::Count))) {
return NS_ERROR_OUT_OF_MEMORY;
}
for (uint32_t process = 0; process < static_cast<uint32_t>(ProcessID::Count); ++process) {
KeyedHistogramSnapshotsArray& hArray = aOutSnapshot[process];
for (size_t i = 0; i < HistogramCount; ++i) {
HistogramID id = HistogramID(i);
const HistogramInfo& info = gHistogramInfos[id];
if (!info.keyed) {
continue;
}
if (!CanRecordInProcess(info.record_in_processes, ProcessID(process)) ||
((ProcessID(process) == ProcessID::Gpu) && !aIncludeGPU)) {
continue;
}
if (!IsInDataset(info.dataset, aDataset)) {
continue;
}
KeyedHistogram* keyed = internal_GetKeyedHistogramById(id,
ProcessID(process),
/* instantiate = */ false);
if (!keyed || (aSkipEmpty && keyed->IsEmpty()) || keyed->IsExpired()) {
continue;
}
// Take a snapshot of the keyed histogram data!
KeyedHistogramSnapshotData snapshot;
if (!NS_SUCCEEDED(keyed->GetSnapshot(aLock, snapshot, aClearSubsession))) {
return NS_ERROR_FAILURE;
}
if (!hArray.emplaceBack(KeyedHistogramSnapshotInfo{std::move(snapshot), id})) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
}
return NS_OK;
}
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE: thread-unsafe helpers for the external interface
namespace {
bool
internal_RemoteAccumulate(const StaticMutexAutoLock& aLock, HistogramID aId, uint32_t aSample)
{
if (XRE_IsParentProcess()) {
return false;
}
if (!internal_IsRecordingEnabled(aId)) {
return true;
}
TelemetryIPCAccumulator::AccumulateChildHistogram(aId, aSample);
return true;
}
bool
internal_RemoteAccumulate(const StaticMutexAutoLock& aLock, HistogramID aId,
const nsCString& aKey, uint32_t aSample)
{
if (XRE_IsParentProcess()) {
return false;
}
if (!internal_IsRecordingEnabled(aId)) {
return true;
}
TelemetryIPCAccumulator::AccumulateChildKeyedHistogram(aId, aKey, aSample);
return true;
}
void internal_Accumulate(const StaticMutexAutoLock& aLock, HistogramID aId, uint32_t aSample)
{
if (!internal_CanRecordBase() ||
internal_RemoteAccumulate(aLock, aId, aSample)) {
return;
}
Histogram *h = internal_GetHistogramById(aLock, aId, ProcessID::Parent);
MOZ_ASSERT(h);
internal_HistogramAdd(aLock, *h, aId, aSample, ProcessID::Parent);
}
void
internal_Accumulate(const StaticMutexAutoLock& aLock, HistogramID aId,
const nsCString& aKey, uint32_t aSample)
{
if (!gInitDone || !internal_CanRecordBase() ||
internal_RemoteAccumulate(aLock, aId, aKey, aSample)) {
return;
}
KeyedHistogram* keyed = internal_GetKeyedHistogramById(aId, ProcessID::Parent);
MOZ_ASSERT(keyed);
keyed->Add(aKey, aSample, ProcessID::Parent);
}
void
internal_AccumulateChild(const StaticMutexAutoLock& aLock,
ProcessID aProcessType,
HistogramID aId,
uint32_t aSample)
{
if (!internal_CanRecordBase()) {
return;
}
if (Histogram* h = internal_GetHistogramById(aLock, aId, aProcessType)) {
internal_HistogramAdd(aLock, *h, aId, aSample, aProcessType);
} else {
NS_WARNING("Failed GetHistogramById for CHILD");
}
}
void
internal_AccumulateChildKeyed(const StaticMutexAutoLock& aLock, ProcessID aProcessType,
HistogramID aId, const nsCString& aKey, uint32_t aSample)
{
if (!gInitDone || !internal_CanRecordBase()) {
return;
}
KeyedHistogram* keyed = internal_GetKeyedHistogramById(aId, aProcessType);
MOZ_ASSERT(keyed);
keyed->Add(aKey, aSample, aProcessType);
}
void
internal_ClearHistogram(const StaticMutexAutoLock& aLock, HistogramID id)
{
MOZ_ASSERT(XRE_IsParentProcess());
if (!XRE_IsParentProcess()) {
return;
}
// Handle keyed histograms.
if (gHistogramInfos[id].keyed) {
for (uint32_t process = 0; process < static_cast<uint32_t>(ProcessID::Count); ++process) {
KeyedHistogram* kh = internal_GetKeyedHistogramById(id, static_cast<ProcessID>(process), /* instantiate = */ false);
if (kh) {
kh->Clear();
}
}
}
// Now reset the histograms instances for all processes.
for (uint32_t process = 0; process < static_cast<uint32_t>(ProcessID::Count); ++process) {
internal_ClearHistogramById(aLock, id, static_cast<ProcessID>(process));
}
}
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE: JSHistogram_* functions
// NOTE: the functions in this section:
//
// internal_JSHistogram_Add
// internal_JSHistogram_Snapshot
// internal_JSHistogram_Clear
// internal_WrapAndReturnHistogram
//
// all run without protection from |gTelemetryHistogramMutex|. If they
// held |gTelemetryHistogramMutex|, there would be the possibility of
// deadlock because the JS_ calls that they make may call back into the
// TelemetryHistogram interface, hence trying to re-acquire the mutex.
//
// This means that these functions potentially race against threads, but
// that seems preferable to risking deadlock.
namespace {
void internal_JSHistogram_finalize(JSFreeOp*, JSObject*);
static const JSClassOps sJSHistogramClassOps = {
nullptr, /* addProperty */
nullptr, /* delProperty */
nullptr, /* enumerate */
nullptr, /* newEnumerate */
nullptr, /* resolve */
nullptr, /* mayResolve */
internal_JSHistogram_finalize
};
static const JSClass sJSHistogramClass = {
"JSHistogram", /* name */
JSCLASS_HAS_PRIVATE | JSCLASS_FOREGROUND_FINALIZE, /* flags */
&sJSHistogramClassOps
};
struct JSHistogramData {
HistogramID histogramId;
};
bool
internal_JSHistogram_CoerceValue(JSContext* aCx, JS::Handle<JS::Value> aElement, HistogramID aId,
uint32_t aHistogramType, uint32_t& aValue)
{
if (aElement.isString()) {
// Strings only allowed for categorical histograms
if (aHistogramType != nsITelemetry::HISTOGRAM_CATEGORICAL) {
LogToBrowserConsole(nsIScriptError::errorFlag,
NS_LITERAL_STRING("String argument only allowed for categorical histogram"));
return false;
}
// Label is given by the string argument
nsAutoJSString label;
if (!label.init(aCx, aElement)) {
LogToBrowserConsole(nsIScriptError::errorFlag, NS_LITERAL_STRING("Invalid string parameter"));
return false;
}
// Get the label id for accumulation
nsresult rv = gHistogramInfos[aId].label_id(NS_ConvertUTF16toUTF8(label).get(), &aValue);
if (NS_FAILED(rv)) {
LogToBrowserConsole(nsIScriptError::errorFlag, NS_LITERAL_STRING("Invalid string label"));
return false;
}
} else if ( !(aElement.isNumber() || aElement.isBoolean()) ) {
LogToBrowserConsole(nsIScriptError::errorFlag, NS_LITERAL_STRING("Argument not a number"));
return false;
} else if ( aElement.isNumber() && aElement.toNumber() > UINT32_MAX ) {
// Clamp large numerical arguments to aValue's acceptable values.
// JS::ToUint32 will take aElement modulo 2^32 before returning it, which
// may result in a smaller final value.
aValue = UINT32_MAX;
#ifdef DEBUG
LogToBrowserConsole(nsIScriptError::errorFlag, NS_LITERAL_STRING("Clamped large numeric value"));
#endif
} else if (!JS::ToUint32(aCx, aElement, &aValue)) {
LogToBrowserConsole(nsIScriptError::errorFlag, NS_LITERAL_STRING("Failed to convert element to UInt32"));
return false;
}
// If we're here then all type checks have passed and aValue contains the coerced integer
return true;
}
bool
internal_JSHistogram_GetValueArray(JSContext* aCx, JS::CallArgs& args, uint32_t aHistogramType, HistogramID aId,
bool isKeyed, nsTArray<uint32_t>& aArray)
{
// This function populates aArray with the values extracted from args. Handles keyed and non-keyed histograms,
// and single and array of values. Also performs sanity checks on the arguments.
// Returns true upon successful population, false otherwise.
uint32_t firstArgIndex = 0;
if (isKeyed) {
firstArgIndex = 1;
}
// Special case of no argument (or only key) and count histogram
if (args.length() == firstArgIndex) {
if (!(aHistogramType == nsITelemetry::HISTOGRAM_COUNT)) {
LogToBrowserConsole(nsIScriptError::errorFlag,
NS_LITERAL_STRING("Need at least one argument for non count type histogram"));
return false;
}
aArray.AppendElement(1);
return true;
}
if (args[firstArgIndex].isObject() && !args[firstArgIndex].isString()) {
JS::Rooted<JSObject*> arrayObj(aCx, &args[firstArgIndex].toObject());
bool isArray = false;
JS_IsArrayObject(aCx, arrayObj, &isArray);
if (!isArray) {
LogToBrowserConsole(nsIScriptError::errorFlag, NS_LITERAL_STRING("The argument to accumulate can't be a non-array object"));
return false;
}
uint32_t arrayLength = 0;
if (!JS_GetArrayLength(aCx, arrayObj, &arrayLength)) {
LogToBrowserConsole(nsIScriptError::errorFlag, NS_LITERAL_STRING("Failed while trying to get array length"));
return false;
}
for (uint32_t arrayIdx = 0; arrayIdx < arrayLength; arrayIdx++) {
JS::Rooted<JS::Value> element(aCx);
if (!JS_GetElement(aCx, arrayObj, arrayIdx, &element)) {
nsPrintfCString msg("Failed while trying to get element at index %d", arrayIdx);
LogToBrowserConsole(nsIScriptError::errorFlag, NS_ConvertUTF8toUTF16(msg));
return false;
}
uint32_t value = 0;
if (!internal_JSHistogram_CoerceValue(aCx, element, aId, aHistogramType, value)) {
nsPrintfCString msg("Element at index %d failed type checks", arrayIdx);
LogToBrowserConsole(nsIScriptError::errorFlag, NS_ConvertUTF8toUTF16(msg));
return false;
}
aArray.AppendElement(value);
}
return true;
}
uint32_t value = 0;
if (!internal_JSHistogram_CoerceValue(aCx, args[firstArgIndex], aId, aHistogramType, value)) {
return false;
}
aArray.AppendElement(value);
return true;
}
bool
internal_JSHistogram_Add(JSContext *cx, unsigned argc, JS::Value *vp)
{
JS::CallArgs args = CallArgsFromVp(argc, vp);
if (!args.thisv().isObject() ||
JS_GetClass(&args.thisv().toObject()) != &sJSHistogramClass) {
JS_ReportErrorASCII(cx, "Wrong JS class, expected JSHistogram class");
return false;
}
JSObject* obj = &args.thisv().toObject();
JSHistogramData* data = static_cast<JSHistogramData*>(JS_GetPrivate(obj));
MOZ_ASSERT(data);
HistogramID id = data->histogramId;
MOZ_ASSERT(internal_IsHistogramEnumId(id));
uint32_t type = gHistogramInfos[id].histogramType;
// This function should always return |undefined| and never fail but
// rather report failures using the console.
args.rval().setUndefined();
nsTArray<uint32_t> values;
if (!internal_JSHistogram_GetValueArray(cx, args, type, id, false, values)) {
// Either GetValueArray or CoerceValue utility function will have printed a meaningful
// error message, so we simply return true
return true;
}
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
for (uint32_t aValue: values) {
internal_Accumulate(locker, id, aValue);
}
}
return true;
}
bool
internal_JSHistogram_Snapshot(JSContext *cx, unsigned argc, JS::Value *vp)
{
JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
if (!args.thisv().isObject() ||
JS_GetClass(&args.thisv().toObject()) != &sJSHistogramClass) {
JS_ReportErrorASCII(cx, "Wrong JS class, expected JSHistogram class");
return false;
}
JSObject* obj = &args.thisv().toObject();
JSHistogramData* data = static_cast<JSHistogramData*>(JS_GetPrivate(obj));
MOZ_ASSERT(data);
HistogramID id = data->histogramId;
HistogramSnapshotData dataSnapshot;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
MOZ_ASSERT(internal_IsHistogramEnumId(id));
// This is not good standard behavior given that we have histogram instances
// covering multiple processes.
// However, changing this requires some broader changes to callers.
Histogram* h = internal_GetHistogramById(locker, id, ProcessID::Parent);
// Take a snapshot of the data here, protected by the lock, and then,
// outside of the lock protection, mirror it to a JS structure
if (NS_FAILED(internal_GetHistogramAndSamples(locker, h, dataSnapshot))) {
return false;
}
}
JS::Rooted<JSObject*> snapshot(cx, JS_NewPlainObject(cx));
if (!snapshot) {
return false;
}
if (NS_FAILED(internal_ReflectHistogramAndSamples(cx,
snapshot,
gHistogramInfos[id],
dataSnapshot))) {
return false;
}
args.rval().setObject(*snapshot);
return true;
}
bool
internal_JSHistogram_Clear(JSContext *cx, unsigned argc, JS::Value *vp)
{
JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
if (!args.thisv().isObject() ||
JS_GetClass(&args.thisv().toObject()) != &sJSHistogramClass) {
JS_ReportErrorASCII(cx, "Wrong JS class, expected JSHistogram class");
return false;
}
JSObject* obj = &args.thisv().toObject();
JSHistogramData* data = static_cast<JSHistogramData*>(JS_GetPrivate(obj));
MOZ_ASSERT(data);
// This function should always return |undefined| and never fail but
// rather report failures using the console.
args.rval().setUndefined();
HistogramID id = data->histogramId;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
MOZ_ASSERT(internal_IsHistogramEnumId(id));
internal_ClearHistogram(locker, id);
}
return true;
}
// NOTE: Runs without protection from |gTelemetryHistogramMutex|.
// See comment at the top of this section.
nsresult
internal_WrapAndReturnHistogram(HistogramID id, JSContext *cx,
JS::MutableHandle<JS::Value> ret)
{
JS::Rooted<JSObject*> obj(cx, JS_NewObject(cx, &sJSHistogramClass));
if (!obj) {
return NS_ERROR_FAILURE;
}
// The 3 functions that are wrapped up here are eventually called
// by the same thread that runs this function.
if (!(JS_DefineFunction(cx, obj, "add", internal_JSHistogram_Add, 1, 0)
&& JS_DefineFunction(cx, obj, "snapshot",
internal_JSHistogram_Snapshot, 0, 0)
&& JS_DefineFunction(cx, obj, "clear", internal_JSHistogram_Clear, 0, 0))) {
return NS_ERROR_FAILURE;
}
JSHistogramData* data = new JSHistogramData{id};
JS_SetPrivate(obj, data);
ret.setObject(*obj);
return NS_OK;
}
void
internal_JSHistogram_finalize(JSFreeOp*, JSObject* obj)
{
if (!obj ||
JS_GetClass(obj) != &sJSHistogramClass) {
MOZ_ASSERT_UNREACHABLE("Should have the right JS class.");
return;
}
JSHistogramData* data = static_cast<JSHistogramData*>(JS_GetPrivate(obj));
MOZ_ASSERT(data);
delete data;
}
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE: JSKeyedHistogram_* functions
// NOTE: the functions in this section:
//
// internal_KeyedHistogram_SnapshotImpl
// internal_JSKeyedHistogram_Add
// internal_JSKeyedHistogram_Keys
// internal_JSKeyedHistogram_Snapshot
// internal_JSKeyedHistogram_Clear
// internal_WrapAndReturnKeyedHistogram
//
// Same comments as above, at the JSHistogram_* section, regarding
// deadlock avoidance, apply.
namespace {
void internal_JSKeyedHistogram_finalize(JSFreeOp*, JSObject*);
static const JSClassOps sJSKeyedHistogramClassOps = {
nullptr, /* addProperty */
nullptr, /* delProperty */
nullptr, /* enumerate */
nullptr, /* newEnumerate */
nullptr, /* resolve */
nullptr, /* mayResolve */
internal_JSKeyedHistogram_finalize
};
static const JSClass sJSKeyedHistogramClass = {
"JSKeyedHistogram", /* name */
JSCLASS_HAS_PRIVATE | JSCLASS_FOREGROUND_FINALIZE, /* flags */
&sJSKeyedHistogramClassOps
};
bool
internal_KeyedHistogram_SnapshotImpl(JSContext *cx, unsigned argc,
JS::Value *vp,
bool clearSubsession)
{
JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
if (!args.thisv().isObject() ||
JS_GetClass(&args.thisv().toObject()) != &sJSKeyedHistogramClass) {
JS_ReportErrorASCII(cx, "Wrong JS class, expected JSKeyedHistogram class");
return false;
}
JSObject *obj = &args.thisv().toObject();
JSHistogramData* data = static_cast<JSHistogramData*>(JS_GetPrivate(obj));
MOZ_ASSERT(data);
HistogramID id = data->histogramId;
MOZ_ASSERT(internal_IsHistogramEnumId(id));
// This function should always return |undefined| and never fail but
// rather report failures using the console.
args.rval().setUndefined();
// This is not good standard behavior given that we have histogram instances
// covering multiple processes.
// However, changing this requires some broader changes to callers.
KeyedHistogram* keyed = internal_GetKeyedHistogramById(id, ProcessID::Parent, /* instantiate = */ true);
if (!keyed) {
JS_ReportErrorASCII(cx, "Failed to look up keyed histogram");
return false;
}
// No argument was passed, so snapshot all the keys.
if (args.length() == 0) {
JS::RootedObject snapshot(cx, JS_NewPlainObject(cx));
if (!snapshot) {
JS_ReportErrorASCII(cx, "Failed to create object");
return false;
}
if (!NS_SUCCEEDED(keyed->GetJSSnapshot(cx, snapshot, clearSubsession))) {
JS_ReportErrorASCII(cx, "Failed to reflect keyed histograms");
return false;
}
args.rval().setObject(*snapshot);
return true;
}
// One argument was passed. If it's a string, use it as a key
// and just snapshot the data for that key.
nsAutoJSString key;
if (!args[0].isString() || !key.init(cx, args[0])) {
JS_ReportErrorASCII(cx, "Not a string");
return false;
}
HistogramSnapshotData dataSnapshot;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
// Get data for the key we're looking for.
Histogram* h = nullptr;
nsresult rv = keyed->GetHistogram(NS_ConvertUTF16toUTF8(key), &h);
if (NS_FAILED(rv)) {
return false;
}
// Take a snapshot of the data here, protected by the lock, and then,
// outside of the lock protection, mirror it to a JS structure
if (NS_FAILED(internal_GetHistogramAndSamples(locker, h, dataSnapshot))) {
return false;
}
}
JS::RootedObject snapshot(cx, JS_NewPlainObject(cx));
if (!snapshot) {
return false;
}
if (NS_FAILED(internal_ReflectHistogramAndSamples(cx,
snapshot,
gHistogramInfos[id],
dataSnapshot))) {
JS_ReportErrorASCII(cx, "Failed to reflect histogram");
return false;
}
args.rval().setObject(*snapshot);
return true;
}
bool
internal_JSKeyedHistogram_Add(JSContext *cx, unsigned argc, JS::Value *vp)
{
JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
if (!args.thisv().isObject() ||
JS_GetClass(&args.thisv().toObject()) != &sJSKeyedHistogramClass) {
JS_ReportErrorASCII(cx, "Wrong JS class, expected JSKeyedHistogram class");
return false;
}
JSObject *obj = &args.thisv().toObject();
JSHistogramData* data = static_cast<JSHistogramData*>(JS_GetPrivate(obj));
MOZ_ASSERT(data);
HistogramID id = data->histogramId;
MOZ_ASSERT(internal_IsHistogramEnumId(id));
// This function should always return |undefined| and never fail but
// rather report failures using the console.
args.rval().setUndefined();
if (args.length() < 1) {
LogToBrowserConsole(nsIScriptError::errorFlag, NS_LITERAL_STRING("Expected one argument"));
return true;
}
nsAutoJSString key;
if (!args[0].isString() || !key.init(cx, args[0])) {
LogToBrowserConsole(nsIScriptError::errorFlag, NS_LITERAL_STRING("Not a string"));
return true;
}
// Check if we're allowed to record in the provided key, for this histogram.
if (!gHistogramInfos[id].allows_key(NS_ConvertUTF16toUTF8(key))) {
nsPrintfCString msg("%s - key '%s' not allowed for this keyed histogram",
gHistogramInfos[id].name(),
NS_ConvertUTF16toUTF8(key).get());
LogToBrowserConsole(nsIScriptError::errorFlag, NS_ConvertUTF8toUTF16(msg));
TelemetryScalar::Add(
mozilla::Telemetry::ScalarID::TELEMETRY_ACCUMULATE_UNKNOWN_HISTOGRAM_KEYS,
NS_ConvertASCIItoUTF16(gHistogramInfos[id].name()), 1);
return true;
}
const uint32_t type = gHistogramInfos[id].histogramType;
nsTArray<uint32_t> values;
if (!internal_JSHistogram_GetValueArray(cx, args, type, id, true, values)) {
// Either GetValueArray or CoerceValue utility function will have printed a meaningful
// error message so we simple return true
return true;
}
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
for (uint32_t aValue: values) {
internal_Accumulate(locker, id, NS_ConvertUTF16toUTF8(key), aValue);
}
}
return true;
}
bool
internal_JSKeyedHistogram_Keys(JSContext *cx, unsigned argc, JS::Value *vp)
{
JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
if (!args.thisv().isObject() ||
JS_GetClass(&args.thisv().toObject()) != &sJSKeyedHistogramClass) {
JS_ReportErrorASCII(cx, "Wrong JS class, expected JSKeyedHistogram class");
return false;
}
JSObject *obj = &args.thisv().toObject();
JSHistogramData* data = static_cast<JSHistogramData*>(JS_GetPrivate(obj));
MOZ_ASSERT(data);
HistogramID id = data->histogramId;
KeyedHistogram* keyed = nullptr;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
MOZ_ASSERT(internal_IsHistogramEnumId(id));
// This is not good standard behavior given that we have histogram instances
// covering multiple processes.
// However, changing this requires some broader changes to callers.
keyed = internal_GetKeyedHistogramById(id, ProcessID::Parent);
}
MOZ_ASSERT(keyed);
if (!keyed) {
return false;
}
return NS_SUCCEEDED(keyed->GetJSKeys(cx, args));
}
bool
internal_JSKeyedHistogram_Snapshot(JSContext *cx, unsigned argc, JS::Value *vp)
{
return internal_KeyedHistogram_SnapshotImpl(cx, argc, vp, false);
}
bool
internal_JSKeyedHistogram_Clear(JSContext *cx, unsigned argc, JS::Value *vp)
{
JS::CallArgs args = JS::CallArgsFromVp(argc, vp);
if (!args.thisv().isObject() ||
JS_GetClass(&args.thisv().toObject()) != &sJSKeyedHistogramClass) {
JS_ReportErrorASCII(cx, "Wrong JS class, expected JSKeyedHistogram class");
return false;
}
JSObject *obj = &args.thisv().toObject();
JSHistogramData* data = static_cast<JSHistogramData*>(JS_GetPrivate(obj));
MOZ_ASSERT(data);
HistogramID id = data->histogramId;
// This function should always return |undefined| and never fail but
// rather report failures using the console.
args.rval().setUndefined();
KeyedHistogram* keyed = nullptr;
{
MOZ_ASSERT(internal_IsHistogramEnumId(id));
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
// This is not good standard behavior given that we have histogram instances
// covering multiple processes.
// However, changing this requires some broader changes to callers.
keyed = internal_GetKeyedHistogramById(id, ProcessID::Parent, /* instantiate = */ false);
if (!keyed) {
return true;
}
keyed->Clear();
}
return true;
}
// NOTE: Runs without protection from |gTelemetryHistogramMutex|.
// See comment at the top of this section.
nsresult
internal_WrapAndReturnKeyedHistogram(HistogramID id, JSContext *cx,
JS::MutableHandle<JS::Value> ret)
{
JS::Rooted<JSObject*> obj(cx, JS_NewObject(cx, &sJSKeyedHistogramClass));
if (!obj)
return NS_ERROR_FAILURE;
// The 6 functions that are wrapped up here are eventually called
// by the same thread that runs this function.
if (!(JS_DefineFunction(cx, obj, "add", internal_JSKeyedHistogram_Add, 2, 0)
&& JS_DefineFunction(cx, obj, "snapshot",
internal_JSKeyedHistogram_Snapshot, 1, 0)
&& JS_DefineFunction(cx, obj, "keys",
internal_JSKeyedHistogram_Keys, 0, 0)
&& JS_DefineFunction(cx, obj, "clear",
internal_JSKeyedHistogram_Clear, 0, 0))) {
return NS_ERROR_FAILURE;
}
JSHistogramData* data = new JSHistogramData{id};
JS_SetPrivate(obj, data);
ret.setObject(*obj);
return NS_OK;
}
void
internal_JSKeyedHistogram_finalize(JSFreeOp*, JSObject* obj)
{
if (!obj ||
JS_GetClass(obj) != &sJSKeyedHistogramClass) {
MOZ_ASSERT_UNREACHABLE("Should have the right JS class.");
return;
}
JSHistogramData* data = static_cast<JSHistogramData*>(JS_GetPrivate(obj));
MOZ_ASSERT(data);
delete data;
}
} // namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// EXTERNALLY VISIBLE FUNCTIONS in namespace TelemetryHistogram::
// All of these functions are actually in namespace TelemetryHistogram::,
// but the ::TelemetryHistogram prefix is given explicitly. This is
// because it is critical to see which calls from these functions are
// to another function in this interface. Mis-identifying "inwards
// calls" from "calls to another function in this interface" will lead
// to deadlocking and/or races. See comments at the top of the file
// for further (important!) details.
void TelemetryHistogram::InitializeGlobalState(bool canRecordBase,
bool canRecordExtended)
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
MOZ_ASSERT(!gInitDone, "TelemetryHistogram::InitializeGlobalState "
"may only be called once");
gCanRecordBase = canRecordBase;
gCanRecordExtended = canRecordExtended;
if (XRE_IsParentProcess()) {
gHistogramStorage =
new Histogram*[HistogramCount * size_t(ProcessID::Count)] {};
gKeyedHistogramStorage =
new KeyedHistogram*[HistogramCount * size_t(ProcessID::Count)] {};
}
// gNameToHistogramIDMap should have been pre-sized correctly at the
// declaration point further up in this file.
// Populate the static histogram name->id cache.
// Note that the histogram names come from a static table so we can wrap them
// in a literal string to avoid allocations when it gets copied.
for (uint32_t i = 0; i < HistogramCount; i++) {
auto name = gHistogramInfos[i].name();
// Make sure the name pointer is in a valid region. See bug 1428612.
MOZ_DIAGNOSTIC_ASSERT(name >= gHistogramStringTable);
MOZ_DIAGNOSTIC_ASSERT(
uintptr_t(name) < (uintptr_t(gHistogramStringTable) + sizeof(gHistogramStringTable)));
nsCString wrappedName;
wrappedName.AssignLiteral(name, strlen(name));
gNameToHistogramIDMap.Put(wrappedName, HistogramID(i));
}
#ifdef DEBUG
gNameToHistogramIDMap.MarkImmutable();
#endif
// Some Telemetry histograms depend on the value of C++ constants and hardcode
// their values in Histograms.json.
// We add static asserts here for those values to match so that future changes
// don't go unnoticed.
static_assert((JS::gcreason::NUM_TELEMETRY_REASONS + 1) ==
gHistogramInfos[mozilla::Telemetry::GC_MINOR_REASON].bucketCount &&
(JS::gcreason::NUM_TELEMETRY_REASONS + 1) ==
gHistogramInfos[mozilla::Telemetry::GC_MINOR_REASON_LONG].bucketCount &&
(JS::gcreason::NUM_TELEMETRY_REASONS + 1) ==
gHistogramInfos[mozilla::Telemetry::GC_REASON_2].bucketCount,
"NUM_TELEMETRY_REASONS is assumed to be a fixed value in Histograms.json."
" If this was an intentional change, update the n_values for the "
"following in Histograms.json: GC_MINOR_REASON, GC_MINOR_REASON_LONG, "
"GC_REASON_2");
static_assert((mozilla::StartupTimeline::MAX_EVENT_ID + 1) ==
gHistogramInfos[mozilla::Telemetry::STARTUP_MEASUREMENT_ERRORS].bucketCount,
"MAX_EVENT_ID is assumed to be a fixed value in Histograms.json. If this"
" was an intentional change, update the n_values for the following in "
"Histograms.json: STARTUP_MEASUREMENT_ERRORS");
gInitDone = true;
}
void TelemetryHistogram::DeInitializeGlobalState()
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
gCanRecordBase = false;
gCanRecordExtended = false;
gNameToHistogramIDMap.Clear();
gInitDone = false;
// FactoryGet `new`s Histograms for us, but requires us to manually delete.
if (XRE_IsParentProcess()) {
for (size_t i = 0; i < HistogramCount * size_t(ProcessID::Count); ++i) {
if (i < HistogramCount * size_t(ProcessID::Count)
&& gKeyedHistogramStorage[i] != gExpiredKeyedHistogram) {
delete gKeyedHistogramStorage[i];
}
if (gHistogramStorage[i] != gExpiredHistogram) {
delete gHistogramStorage[i];
}
}
delete[] gHistogramStorage;
delete[] gKeyedHistogramStorage;
}
delete gExpiredHistogram;
gExpiredHistogram = nullptr;
delete gExpiredKeyedHistogram;
gExpiredKeyedHistogram = nullptr;
}
#ifdef DEBUG
bool TelemetryHistogram::GlobalStateHasBeenInitialized() {
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
return gInitDone;
}
#endif
bool
TelemetryHistogram::CanRecordBase() {
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
return internal_CanRecordBase();
}
void
TelemetryHistogram::SetCanRecordBase(bool b) {
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
gCanRecordBase = b;
}
bool
TelemetryHistogram::CanRecordExtended() {
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
return internal_CanRecordExtended();
}
void
TelemetryHistogram::SetCanRecordExtended(bool b) {
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
gCanRecordExtended = b;
}
void
TelemetryHistogram::InitHistogramRecordingEnabled()
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
auto processType = XRE_GetProcessType();
for (size_t i = 0; i < HistogramCount; ++i) {
const HistogramInfo& h = gHistogramInfos[i];
mozilla::Telemetry::HistogramID id = mozilla::Telemetry::HistogramID(i);
bool canRecordInProcess = CanRecordInProcess(h.record_in_processes, processType);
bool canRecordProduct = CanRecordProduct(h.products);
internal_SetHistogramRecordingEnabled(locker, id, canRecordInProcess && canRecordProduct);
}
for (auto recordingInitiallyDisabledID : kRecordingInitiallyDisabledIDs) {
internal_SetHistogramRecordingEnabled(locker,
recordingInitiallyDisabledID,
false);
}
}
void
TelemetryHistogram::SetHistogramRecordingEnabled(HistogramID aID,
bool aEnabled)
{
if (NS_WARN_IF(!internal_IsHistogramEnumId(aID))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids.");
return;
}
const HistogramInfo& h = gHistogramInfos[aID];
if (!CanRecordInProcess(h.record_in_processes, XRE_GetProcessType())) {
// Don't permit record_in_process-disabled recording to be re-enabled.
return;
}
if (!CanRecordProduct(h.products)) {
// Don't permit products-disabled recording to be re-enabled.
return;
}
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
internal_SetHistogramRecordingEnabled(locker, aID, aEnabled);
}
nsresult
TelemetryHistogram::SetHistogramRecordingEnabled(const nsACString& name,
bool aEnabled)
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
HistogramID id;
if (NS_FAILED(internal_GetHistogramIdByName(locker, name, &id))) {
return NS_ERROR_FAILURE;
}
const HistogramInfo& hi = gHistogramInfos[id];
if (CanRecordInProcess(hi.record_in_processes, XRE_GetProcessType())) {
internal_SetHistogramRecordingEnabled(locker, id, aEnabled);
}
return NS_OK;
}
void
TelemetryHistogram::Accumulate(HistogramID aID,
uint32_t aSample)
{
if (NS_WARN_IF(!internal_IsHistogramEnumId(aID))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids.");
return;
}
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
internal_Accumulate(locker, aID, aSample);
}
void
TelemetryHistogram::Accumulate(HistogramID aID, const nsTArray<uint32_t>& aSamples)
{
if (NS_WARN_IF(!internal_IsHistogramEnumId(aID))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids.");
return;
}
MOZ_ASSERT(!gHistogramInfos[aID].keyed, "Cannot accumulate into a keyed histogram. No key given.");
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
for(uint32_t sample: aSamples){
internal_Accumulate(locker, aID, sample);
}
}
void
TelemetryHistogram::Accumulate(HistogramID aID,
const nsCString& aKey, uint32_t aSample)
{
if (NS_WARN_IF(!internal_IsHistogramEnumId(aID))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids.");
return;
}
// Check if we're allowed to record in the provided key, for this histogram.
if (!gHistogramInfos[aID].allows_key(aKey)) {
nsPrintfCString msg("%s - key '%s' not allowed for this keyed histogram",
gHistogramInfos[aID].name(),
aKey.get());
LogToBrowserConsole(nsIScriptError::errorFlag, NS_ConvertUTF8toUTF16(msg));
TelemetryScalar::Add(
mozilla::Telemetry::ScalarID::TELEMETRY_ACCUMULATE_UNKNOWN_HISTOGRAM_KEYS,
NS_ConvertASCIItoUTF16(gHistogramInfos[aID].name()), 1);
return;
}
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
internal_Accumulate(locker, aID, aKey, aSample);
}
void
TelemetryHistogram::Accumulate(HistogramID aID, const nsCString& aKey,
const nsTArray<uint32_t>& aSamples)
{
if (NS_WARN_IF(!internal_IsHistogramEnumId(aID))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids");
return;
}
// Check that this histogram is keyed
MOZ_ASSERT(gHistogramInfos[aID].keyed, "Cannot accumulate into a non-keyed histogram using a key.");
// Check if we're allowed to record in the provided key, for this histogram.
if (!gHistogramInfos[aID].allows_key(aKey)) {
nsPrintfCString msg("%s - key '%s' not allowed for this keyed histogram",
gHistogramInfos[aID].name(),
aKey.get());
LogToBrowserConsole(nsIScriptError::errorFlag, NS_ConvertUTF8toUTF16(msg));
TelemetryScalar::Add(
mozilla::Telemetry::ScalarID::TELEMETRY_ACCUMULATE_UNKNOWN_HISTOGRAM_KEYS,
NS_ConvertASCIItoUTF16(gHistogramInfos[aID].name()), 1);
return;
}
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
for(uint32_t sample: aSamples){
internal_Accumulate(locker, aID, aKey, sample);
}
}
void
TelemetryHistogram::Accumulate(const char* name, uint32_t sample)
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
if (!internal_CanRecordBase()) {
return;
}
HistogramID id;
nsresult rv = internal_GetHistogramIdByName(locker, nsDependentCString(name), &id);
if (NS_FAILED(rv)) {
return;
}
internal_Accumulate(locker, id, sample);
}
void
TelemetryHistogram::Accumulate(const char* name,
const nsCString& key, uint32_t sample)
{
bool keyNotAllowed = false;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
if (!internal_CanRecordBase()) {
return;
}
HistogramID id;
nsresult rv = internal_GetHistogramIdByName(locker, nsDependentCString(name), &id);
if (NS_SUCCEEDED(rv)) {
// Check if we're allowed to record in the provided key, for this histogram.
if (gHistogramInfos[id].allows_key(key)) {
internal_Accumulate(locker, id, key, sample);
return;
}
// We're holding |gTelemetryHistogramMutex|, so we can't print a message
// here.
keyNotAllowed = true;
}
}
if (keyNotAllowed) {
LogToBrowserConsole(nsIScriptError::errorFlag,
NS_LITERAL_STRING("Key not allowed for this keyed histogram"));
TelemetryScalar::Add(
mozilla::Telemetry::ScalarID::TELEMETRY_ACCUMULATE_UNKNOWN_HISTOGRAM_KEYS,
NS_ConvertASCIItoUTF16(name), 1);
}
}
void
TelemetryHistogram::AccumulateCategorical(HistogramID aId,
const nsCString& label)
{
if (NS_WARN_IF(!internal_IsHistogramEnumId(aId))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids.");
return;
}
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
if (!internal_CanRecordBase()) {
return;
}
uint32_t labelId = 0;
if (NS_FAILED(gHistogramInfos[aId].label_id(label.get(), &labelId))) {
return;
}
internal_Accumulate(locker, aId, labelId);
}
void
TelemetryHistogram::AccumulateCategorical(HistogramID aId, const nsTArray<nsCString>& aLabels)
{
if (NS_WARN_IF(!internal_IsHistogramEnumId(aId))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids.");
return;
}
if (!internal_CanRecordBase()) {
return;
}
// We use two loops, one for getting label_ids and another one for actually accumulating
// the values. This ensures that in the case of an invalid label in the array, no values
// are accumulated. In any call to this API, either all or (in case of error) none of the
// values will be accumulated.
nsTArray<uint32_t> intSamples(aLabels.Length());
for (const nsCString& label: aLabels){
uint32_t labelId = 0;
if (NS_FAILED(gHistogramInfos[aId].label_id(label.get(), &labelId))) {
return;
}
intSamples.AppendElement(labelId);
}
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
for (uint32_t sample: intSamples){
internal_Accumulate(locker, aId, sample);
}
}
void
TelemetryHistogram::AccumulateChild(ProcessID aProcessType,
const nsTArray<HistogramAccumulation>& aAccumulations)
{
MOZ_ASSERT(XRE_IsParentProcess());
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
if (!internal_CanRecordBase()) {
return;
}
for (uint32_t i = 0; i < aAccumulations.Length(); ++i) {
if (NS_WARN_IF(!internal_IsHistogramEnumId(aAccumulations[i].mId))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids.");
continue;
}
internal_AccumulateChild(locker,
aProcessType,
aAccumulations[i].mId,
aAccumulations[i].mSample);
}
}
void
TelemetryHistogram::AccumulateChildKeyed(ProcessID aProcessType,
const nsTArray<KeyedHistogramAccumulation>& aAccumulations)
{
MOZ_ASSERT(XRE_IsParentProcess());
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
if (!internal_CanRecordBase()) {
return;
}
for (uint32_t i = 0; i < aAccumulations.Length(); ++i) {
if (NS_WARN_IF(!internal_IsHistogramEnumId(aAccumulations[i].mId))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids.");
continue;
}
internal_AccumulateChildKeyed(locker,
aProcessType,
aAccumulations[i].mId,
aAccumulations[i].mKey,
aAccumulations[i].mSample);
}
}
nsresult
TelemetryHistogram::GetHistogramById(const nsACString &name, JSContext *cx,
JS::MutableHandle<JS::Value> ret)
{
HistogramID id;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
nsresult rv = internal_GetHistogramIdByName(locker, name, &id);
if (NS_FAILED(rv)) {
return NS_ERROR_FAILURE;
}
if (gHistogramInfos[id].keyed) {
return NS_ERROR_FAILURE;
}
}
// Runs without protection from |gTelemetryHistogramMutex|
return internal_WrapAndReturnHistogram(id, cx, ret);
}
nsresult
TelemetryHistogram::GetKeyedHistogramById(const nsACString &name,
JSContext *cx,
JS::MutableHandle<JS::Value> ret)
{
HistogramID id;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
nsresult rv = internal_GetHistogramIdByName(locker, name, &id);
if (NS_FAILED(rv)) {
return NS_ERROR_FAILURE;
}
if (!gHistogramInfos[id].keyed) {
return NS_ERROR_FAILURE;
}
}
// Runs without protection from |gTelemetryHistogramMutex|
return internal_WrapAndReturnKeyedHistogram(id, cx, ret);
}
const char*
TelemetryHistogram::GetHistogramName(HistogramID id)
{
if (NS_WARN_IF(!internal_IsHistogramEnumId(id))) {
MOZ_ASSERT_UNREACHABLE("Histogram usage requires valid ids.");
return nullptr;
}
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
const HistogramInfo& h = gHistogramInfos[id];
return h.name();
}
nsresult
TelemetryHistogram::CreateHistogramSnapshots(JSContext* aCx,
JS::MutableHandleValue aResult,
unsigned int aDataset,
bool aClearSubsession)
{
// Runs without protection from |gTelemetryHistogramMutex|
JS::Rooted<JSObject*> root_obj(aCx, JS_NewPlainObject(aCx));
if (!root_obj) {
return NS_ERROR_FAILURE;
}
aResult.setObject(*root_obj);
// Include the GPU process in histogram snapshots only if we actually tried
// to launch a process for it.
bool includeGPUProcess = internal_AttemptedGPUProcess();
HistogramProcessSnapshotsArray processHistArray;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
nsresult rv = internal_GetHistogramsSnapshot(locker,
aDataset,
aClearSubsession,
includeGPUProcess,
processHistArray);
if (NS_FAILED(rv)) {
return rv;
}
}
// Make the JS calls on the stashed histograms for every process
for (uint32_t process = 0; process < processHistArray.length(); ++process) {
JS::Rooted<JSObject*> processObject(aCx, JS_NewPlainObject(aCx));
if (!processObject) {
return NS_ERROR_FAILURE;
}
if (!JS_DefineProperty(aCx, root_obj,
GetNameForProcessID(ProcessID(process)),
processObject, JSPROP_ENUMERATE)) {
return NS_ERROR_FAILURE;
}
for (const HistogramSnapshotInfo& hData : processHistArray[process]) {
HistogramID id = hData.histogramID;
JS::Rooted<JSObject*> hobj(aCx, JS_NewPlainObject(aCx));
if (!hobj) {
return NS_ERROR_FAILURE;
}
if (NS_FAILED(internal_ReflectHistogramAndSamples(aCx,
hobj,
gHistogramInfos[id],
hData.data))) {
return NS_ERROR_FAILURE;
}
if (!JS_DefineProperty(aCx, processObject, gHistogramInfos[id].name(),
hobj, JSPROP_ENUMERATE)) {
return NS_ERROR_FAILURE;
}
}
}
return NS_OK;
}
nsresult
TelemetryHistogram::GetKeyedHistogramSnapshots(JSContext* aCx,
JS::MutableHandleValue aResult,
unsigned int aDataset,
bool aClearSubsession)
{
// Runs without protection from |gTelemetryHistogramMutex|
JS::Rooted<JSObject*> obj(aCx, JS_NewPlainObject(aCx));
if (!obj) {
return NS_ERROR_FAILURE;
}
aResult.setObject(*obj);
// Include the GPU process in histogram snapshots only if we actually tried
// to launch a process for it.
bool includeGPUProcess = internal_AttemptedGPUProcess();
// Get a snapshot of all the data while holding the mutex.
KeyedHistogramProcessSnapshotsArray processHistArray;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
nsresult rv = internal_GetKeyedHistogramsSnapshot(locker,
aDataset,
aClearSubsession,
includeGPUProcess,
processHistArray);
if (NS_FAILED(rv)) {
return rv;
}
}
// Mirror the snapshot data to JS, now that we released the mutex.
for (uint32_t process = 0; process < processHistArray.length(); ++process) {
JS::Rooted<JSObject*> processObject(aCx, JS_NewPlainObject(aCx));
if (!processObject) {
return NS_ERROR_FAILURE;
}
if (!JS_DefineProperty(aCx, obj, GetNameForProcessID(ProcessID(process)),
processObject, JSPROP_ENUMERATE)) {
return NS_ERROR_FAILURE;
}
for (const KeyedHistogramSnapshotInfo& hData : processHistArray[process]) {
const HistogramInfo& info = gHistogramInfos[hData.histogramId];
JS::RootedObject snapshot(aCx, JS_NewPlainObject(aCx));
if (!snapshot) {
return NS_ERROR_FAILURE;
}
if (!NS_SUCCEEDED(internal_ReflectKeyedHistogram(hData.data, info, aCx, snapshot))) {
return NS_ERROR_FAILURE;
}
if (!JS_DefineProperty(aCx, processObject, info.name(),
snapshot, JSPROP_ENUMERATE)) {
return NS_ERROR_FAILURE;
}
}
}
return NS_OK;
}
size_t
TelemetryHistogram::GetMapShallowSizesOfExcludingThis(mozilla::MallocSizeOf
aMallocSizeOf)
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
return gNameToHistogramIDMap.ShallowSizeOfExcludingThis(aMallocSizeOf);
}
size_t
TelemetryHistogram::GetHistogramSizesofIncludingThis(mozilla::MallocSizeOf
aMallocSizeOf)
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
// TODO
return 0;
}
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PRIVATE: GeckoView specific helpers
namespace base {
class PersistedSampleSet : public Histogram::SampleSet
{
public:
explicit PersistedSampleSet(const nsTArray<Histogram::Count>& aCounts,
int64_t aSampleSum);
};
PersistedSampleSet::PersistedSampleSet(const nsTArray<Histogram::Count>& aCounts,
int64_t aSampleSum)
{
// Initialize the data in the base class. See Histogram::SampleSet
// for the fields documentation.
const size_t numCounts = aCounts.Length();
counts_.SetLength(numCounts);
for (size_t i = 0; i < numCounts; i++) {
counts_[i] = aCounts[i];
redundant_count_ += aCounts[i];
}
sum_ = aSampleSum;
};
} // base (from ipc/chromium/src/base)
namespace {
/**
* Helper function to write histogram properties to JSON.
* Please note that this needs to be called between
* StartObjectProperty/EndObject calls that mark the histogram's
* JSON creation.
*/
void
internal_ReflectHistogramToJSON(const HistogramSnapshotData& aSnapshot,
mozilla::JSONWriter& aWriter)
{
aWriter.IntProperty("sum", aSnapshot.mSampleSum);
// Fill the "counts" property.
aWriter.StartArrayProperty("counts");
for (size_t i = 0; i < aSnapshot.mBucketCounts.Length(); i++) {
aWriter.IntElement(aSnapshot.mBucketCounts[i]);
}
aWriter.EndArray();
}
bool
internal_CanRecordHistogram(const HistogramID id,
ProcessID aProcessType)
{
// Check if we are allowed to record the data.
if (!CanRecordDataset(gHistogramInfos[id].dataset,
internal_CanRecordBase(),
internal_CanRecordExtended())) {
return false;
}
// Check if we're allowed to record in the given process.
if (aProcessType == ProcessID::Parent && !internal_IsRecordingEnabled(id)) {
return false;
}
if (aProcessType != ProcessID::Parent
&& !CanRecordInProcess(gHistogramInfos[id].record_in_processes, aProcessType)) {
return false;
}
// Don't record if the current platform is not enabled
if (!CanRecordProduct(gHistogramInfos[id].products)) {
return false;
}
return true;
}
nsresult
internal_ParseHistogramData(JSContext* aCx, JS::HandleId aEntryId,
JS::HandleObject aContainerObj, nsACString& aOutName,
nsTArray<Histogram::Count>& aOutCountArray, int64_t& aOutSum)
{
// Get the histogram name.
nsAutoJSString histogramName;
if (!histogramName.init(aCx, aEntryId)) {
JS_ClearPendingException(aCx);
return NS_ERROR_FAILURE;
}
aOutName = NS_ConvertUTF16toUTF8(histogramName);
// Get the data for this histogram.
JS::RootedValue histogramData(aCx);
if (!JS_GetPropertyById(aCx, aContainerObj, aEntryId, &histogramData)) {
JS_ClearPendingException(aCx);
return NS_ERROR_FAILURE;
}
if (!histogramData.isObject()) {
// Histogram data need to be an object. If that's not the case, skip it
// and try to load the rest of the data.
return NS_ERROR_FAILURE;
}
// Get the "sum" property.
JS::RootedValue sumValue(aCx);
JS::RootedObject histogramObj(aCx, &histogramData.toObject());
if (!JS_GetProperty(aCx, histogramObj, "sum", &sumValue)) {
JS_ClearPendingException(aCx);
return NS_ERROR_FAILURE;
}
if (!JS::ToInt64(aCx, sumValue, &aOutSum)) {
JS_ClearPendingException(aCx);
return NS_ERROR_FAILURE;
}
// Get the "counts" array.
JS::RootedValue countsArray(aCx);
bool countsIsArray = false;
if (!JS_GetProperty(aCx, histogramObj, "counts", &countsArray)
|| !JS_IsArrayObject(aCx, countsArray, &countsIsArray)) {
JS_ClearPendingException(aCx);
return NS_ERROR_FAILURE;
}
if (!countsIsArray) {
// The "counts" property needs to be an array. If this is not the case,
// skip this histogram.
return NS_ERROR_FAILURE;
}
// Get the length of the array.
uint32_t countsLen = 0;
JS::RootedObject countsArrayObj(aCx, &countsArray.toObject());
if (!JS_GetArrayLength(aCx, countsArrayObj, &countsLen)) {
JS_ClearPendingException(aCx);
return NS_ERROR_FAILURE;
}
// Parse the "counts" in the array.
for (uint32_t arrayIdx = 0; arrayIdx < countsLen; arrayIdx++) {
JS::RootedValue elementValue(aCx);
int countAsInt = 0;
if (!JS_GetElement(aCx, countsArrayObj, arrayIdx, &elementValue)
|| !JS::ToInt32(aCx, elementValue, &countAsInt)) {
JS_ClearPendingException(aCx);
return NS_ERROR_FAILURE;
}
aOutCountArray.AppendElement(countAsInt);
}
return NS_OK;
}
} // Anonymous namespace
////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////
//
// PUBLIC: GeckoView serialization/deserialization functions.
nsresult
TelemetryHistogram::SerializeHistograms(mozilla::JSONWriter& aWriter)
{
MOZ_ASSERT(XRE_IsParentProcess(), "Only save histograms in the parent process");
if (!XRE_IsParentProcess()) {
return NS_ERROR_FAILURE;
}
// Include the GPU process in histogram snapshots only if we actually tried
// to launch a process for it.
bool includeGPUProcess = internal_AttemptedGPUProcess();
// Take a snapshot of the histograms.
HistogramProcessSnapshotsArray processHistArray;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
// We always request the "opt-in"/"prerelease" dataset: we internally
// record the right subset, so this will only return "prerelease" if
// it was recorded.
if (NS_FAILED(internal_GetHistogramsSnapshot(locker,
nsITelemetry::DATASET_RELEASE_CHANNEL_OPTIN,
false /* aClearSubsession */,
includeGPUProcess,
processHistArray))) {
return NS_ERROR_FAILURE;
}
}
// Make the JSON calls on the stashed histograms for every process
for (uint32_t process = 0; process < processHistArray.length(); ++process) {
aWriter.StartObjectProperty(GetNameForProcessID(ProcessID(process)));
for (const HistogramSnapshotInfo& hData : processHistArray[process]) {
HistogramID id = hData.histogramID;
aWriter.StartObjectProperty(gHistogramInfos[id].name());
internal_ReflectHistogramToJSON(hData.data, aWriter);
aWriter.EndObject();
}
aWriter.EndObject();
}
return NS_OK;
}
nsresult
TelemetryHistogram::SerializeKeyedHistograms(mozilla::JSONWriter& aWriter)
{
MOZ_ASSERT(XRE_IsParentProcess(), "Only save keyed histograms in the parent process");
if (!XRE_IsParentProcess()) {
return NS_ERROR_FAILURE;
}
// Include the GPU process in histogram snapshots only if we actually tried
// to launch a process for it.
bool includeGPUProcess = internal_AttemptedGPUProcess();
// Take a snapshot of the keyed histograms.
KeyedHistogramProcessSnapshotsArray processHistArray;
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
// We always request the "opt-in"/"prerelease" dataset: we internally
// record the right subset, so this will only return "prerelease" if
// it was recorded.
if (NS_FAILED(internal_GetKeyedHistogramsSnapshot(locker,
nsITelemetry::DATASET_RELEASE_CHANNEL_OPTIN,
false /* aClearSubsession */,
includeGPUProcess,
processHistArray,
true /* aSkipEmpty */))) {
return NS_ERROR_FAILURE;
}
}
// Serialize the keyed histograms for every process.
for (uint32_t process = 0; process < processHistArray.length(); ++process) {
aWriter.StartObjectProperty(GetNameForProcessID(ProcessID(process)));
const KeyedHistogramSnapshotsArray& hArray = processHistArray[process];
for (size_t i = 0; i < hArray.length(); ++i) {
const KeyedHistogramSnapshotInfo& hData = hArray[i];
HistogramID id = hData.histogramId;
const HistogramInfo& info = gHistogramInfos[id];
aWriter.StartObjectProperty(info.name());
// Each key is a new object with a "sum" and a "counts" property.
for (auto iter = hData.data.ConstIter(); !iter.Done(); iter.Next()) {
HistogramSnapshotData& keyData = iter.Data();
aWriter.StartObjectProperty(PromiseFlatCString(iter.Key()).get());
internal_ReflectHistogramToJSON(keyData, aWriter);
aWriter.EndObject();
}
aWriter.EndObject();
}
aWriter.EndObject();
}
return NS_OK;
}
nsresult
TelemetryHistogram::DeserializeHistograms(JSContext* aCx, JS::HandleValue aData)
{
MOZ_ASSERT(XRE_IsParentProcess(), "Only load histograms in the parent process");
if (!XRE_IsParentProcess()) {
return NS_ERROR_FAILURE;
}
// Telemetry is disabled. This should never happen, but let's leave this check
// for consistency with other histogram updates routines.
if (!internal_CanRecordBase()) {
return NS_OK;
}
typedef mozilla::Tuple<nsCString, nsTArray<Histogram::Count>, int64_t>
PersistedHistogramTuple;
typedef mozilla::Vector<PersistedHistogramTuple> PersistedHistogramArray;
typedef mozilla::Vector<PersistedHistogramArray> PersistedHistogramStorage;
// Before updating the histograms, we need to get the data out of the JS
// wrappers. We can't hold the histogram mutex while handling JS stuff.
// Build a <histogram name, value> map.
JS::RootedObject histogramDataObj(aCx, &aData.toObject());
JS::Rooted<JS::IdVector> processes(aCx, JS::IdVector(aCx));
if (!JS_Enumerate(aCx, histogramDataObj, &processes)) {
// We can't even enumerate the processes in the loaded data, so
// there is nothing we could recover from the persistence file. Bail out.
JS_ClearPendingException(aCx);
return NS_ERROR_FAILURE;
}
// Make sure we have enough storage for all the processes.
PersistedHistogramStorage histogramsToUpdate;
if (!histogramsToUpdate.resize(static_cast<uint32_t>(ProcessID::Count))) {
return NS_ERROR_OUT_OF_MEMORY;
}
// The following block of code attempts to extract as much data as possible
// from the serialized JSON, even in case of light data corruptions: if, for example,
// the data for a single process is corrupted or is in an unexpected form, we press on
// and attempt to load the data for the other processes.
JS::RootedId process(aCx);
for (auto& processVal : processes) {
// This is required as JS API calls require an Handle<jsid> and not a
// plain jsid.
process = processVal;
// Get the process name.
nsAutoJSString processNameJS;
if (!processNameJS.init(aCx, process)) {
JS_ClearPendingException(aCx);
continue;
}
// Make sure it's valid. Note that this is safe to call outside
// of a locked section.
NS_ConvertUTF16toUTF8 processName(processNameJS);
ProcessID processID = GetIDForProcessName(processName.get());
if (processID == ProcessID::Count) {
NS_WARNING(nsPrintfCString("Failed to get process ID for %s", processName.get()).get());
continue;
}
// And its probes.
JS::RootedValue processData(aCx);
if (!JS_GetPropertyById(aCx, histogramDataObj, process, &processData)) {
JS_ClearPendingException(aCx);
continue;
}
if (!processData.isObject()) {
// |processData| should be an object containing histograms. If this is
// not the case, silently skip and try to load the data for the other
// processes.
continue;
}
// Iterate through each histogram.
JS::RootedObject processDataObj(aCx, &processData.toObject());
JS::Rooted<JS::IdVector> histograms(aCx, JS::IdVector(aCx));
if (!JS_Enumerate(aCx, processDataObj, &histograms)) {
JS_ClearPendingException(aCx);
continue;
}
// Get a reference to the deserialized data for this process.
PersistedHistogramArray& deserializedProcessData =
histogramsToUpdate[static_cast<uint32_t>(processID)];
JS::RootedId histogram(aCx);
for (auto& histogramVal : histograms) {
histogram = histogramVal;
int64_t sum = 0;
nsTArray<Histogram::Count> deserializedCounts;
nsCString histogramName;
if (NS_FAILED(internal_ParseHistogramData(aCx, histogram, processDataObj,
histogramName, deserializedCounts, sum))) {
continue;
}
// Finally append the deserialized data to the storage.
if (!deserializedProcessData.emplaceBack(
MakeTuple(std::move(histogramName), std::move(deserializedCounts), sum))) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
}
// Update the histogram storage.
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
for (uint32_t process = 0; process < histogramsToUpdate.length(); ++process) {
PersistedHistogramArray& processArray = histogramsToUpdate[process];
for (auto& histogramData : processArray) {
// Attempt to get the corresponding ID for the deserialized histogram name.
HistogramID id;
if (NS_FAILED(internal_GetHistogramIdByName(locker, mozilla::Get<0>(histogramData), &id))) {
continue;
}
ProcessID procID = static_cast<ProcessID>(process);
if (!internal_CanRecordHistogram(id, procID)) {
// We're not allowed to record this, so don't try to restore it.
continue;
}
// Get the Histogram instance: this will instantiate it if it doesn't exist.
Histogram* h = internal_GetHistogramById(locker, id, procID);
MOZ_ASSERT(h);
if (!h || internal_IsExpired(locker, h)) {
// Don't restore expired histograms.
continue;
}
// Make sure that histogram counts have matching sizes. If not,
// |AddSampleSet| will fail and crash.
size_t numCounts = mozilla::Get<1>(histogramData).Length();
if (h->bucket_count() != numCounts) {
MOZ_ASSERT(false,
"The number of restored buckets does not match with the on in the definition");
continue;
}
// Update the data for the histogram.
h->AddSampleSet(base::PersistedSampleSet(std::move(mozilla::Get<1>(histogramData)),
mozilla::Get<2>(histogramData)));
}
}
}
return NS_OK;
}
nsresult
TelemetryHistogram::DeserializeKeyedHistograms(JSContext* aCx, JS::HandleValue aData)
{
MOZ_ASSERT(XRE_IsParentProcess(), "Only load keyed histograms in the parent process");
if (!XRE_IsParentProcess()) {
return NS_ERROR_FAILURE;
}
// Telemetry is disabled. This should never happen, but let's leave this check
// for consistency with other histogram updates routines.
if (!internal_CanRecordBase()) {
return NS_OK;
}
typedef mozilla::Tuple<nsCString, nsCString, nsTArray<Histogram::Count>, int64_t>
PersistedKeyedHistogramTuple;
typedef mozilla::Vector<PersistedKeyedHistogramTuple> PersistedKeyedHistogramArray;
typedef mozilla::Vector<PersistedKeyedHistogramArray> PersistedKeyedHistogramStorage;
// Before updating the histograms, we need to get the data out of the JS
// wrappers. We can't hold the histogram mutex while handling JS stuff.
// Build a <histogram name, value> map.
JS::RootedObject histogramDataObj(aCx, &aData.toObject());
JS::Rooted<JS::IdVector> processes(aCx, JS::IdVector(aCx));
if (!JS_Enumerate(aCx, histogramDataObj, &processes)) {
// We can't even enumerate the processes in the loaded data, so
// there is nothing we could recover from the persistence file. Bail out.
JS_ClearPendingException(aCx);
return NS_ERROR_FAILURE;
}
// Make sure we have enough storage for all the processes.
PersistedKeyedHistogramStorage histogramsToUpdate;
if (!histogramsToUpdate.resize(static_cast<uint32_t>(ProcessID::Count))) {
return NS_ERROR_OUT_OF_MEMORY;
}
// The following block of code attempts to extract as much data as possible
// from the serialized JSON, even in case of light data corruptions: if, for example,
// the data for a single process is corrupted or is in an unexpected form, we press on
// and attempt to load the data for the other processes.
JS::RootedId process(aCx);
for (auto& processVal : processes) {
// This is required as JS API calls require an Handle<jsid> and not a
// plain jsid.
process = processVal;
// Get the process name.
nsAutoJSString processNameJS;
if (!processNameJS.init(aCx, process)) {
JS_ClearPendingException(aCx);
continue;
}
// Make sure it's valid. Note that this is safe to call outside
// of a locked section.
NS_ConvertUTF16toUTF8 processName(processNameJS);
ProcessID processID = GetIDForProcessName(processName.get());
if (processID == ProcessID::Count) {
NS_WARNING(nsPrintfCString("Failed to get process ID for %s", processName.get()).get());
continue;
}
// And its probes.
JS::RootedValue processData(aCx);
if (!JS_GetPropertyById(aCx, histogramDataObj, process, &processData)) {
JS_ClearPendingException(aCx);
continue;
}
if (!processData.isObject()) {
// |processData| should be an object containing histograms. If this is
// not the case, silently skip and try to load the data for the other
// processes.
continue;
}
// Iterate through each keyed histogram.
JS::RootedObject processDataObj(aCx, &processData.toObject());
JS::Rooted<JS::IdVector> histograms(aCx, JS::IdVector(aCx));
if (!JS_Enumerate(aCx, processDataObj, &histograms)) {
JS_ClearPendingException(aCx);
continue;
}
// Get a reference to the deserialized data for this process.
PersistedKeyedHistogramArray& deserializedProcessData =
histogramsToUpdate[static_cast<uint32_t>(processID)];
JS::RootedId histogram(aCx);
for (auto& histogramVal : histograms) {
histogram = histogramVal;
// Get the histogram name.
nsAutoJSString histogramName;
if (!histogramName.init(aCx, histogram)) {
JS_ClearPendingException(aCx);
continue;
}
// Get the data for this histogram.
JS::RootedValue histogramData(aCx);
if (!JS_GetPropertyById(aCx, processDataObj, histogram, &histogramData)) {
JS_ClearPendingException(aCx);
continue;
}
// Iterate through each key in the histogram.
JS::RootedObject keysDataObj(aCx, &histogramData.toObject());
JS::Rooted<JS::IdVector> keys(aCx, JS::IdVector(aCx));
if (!JS_Enumerate(aCx, keysDataObj, &keys)) {
JS_ClearPendingException(aCx);
continue;
}
JS::RootedId key(aCx);
for (auto& keyVal : keys) {
key = keyVal;
int64_t sum = 0;
nsTArray<Histogram::Count> deserializedCounts;
nsCString keyName;
if (NS_FAILED(internal_ParseHistogramData(aCx, key, keysDataObj, keyName,
deserializedCounts, sum))) {
continue;
}
// Finally append the deserialized data to the storage.
if (!deserializedProcessData.emplaceBack(
MakeTuple(nsCString(NS_ConvertUTF16toUTF8(histogramName)), std::move(keyName),
std::move(deserializedCounts), sum))) {
return NS_ERROR_OUT_OF_MEMORY;
}
}
}
}
// Update the keyed histogram storage.
{
StaticMutexAutoLock locker(gTelemetryHistogramMutex);
for (uint32_t process = 0; process < histogramsToUpdate.length(); ++process) {
PersistedKeyedHistogramArray& processArray = histogramsToUpdate[process];
for (auto& histogramData : processArray) {
// Attempt to get the corresponding ID for the deserialized histogram name.
HistogramID id;
if (NS_FAILED(internal_GetHistogramIdByName(locker, mozilla::Get<0>(histogramData), &id))) {
continue;
}
ProcessID procID = static_cast<ProcessID>(process);
if (!internal_CanRecordHistogram(id, procID)) {
// We're not allowed to record this, so don't try to restore it.
continue;
}
KeyedHistogram* keyed = internal_GetKeyedHistogramById(id, procID);
MOZ_ASSERT(keyed);
if (!keyed) {
// Don't restore if we don't have a destination storage.
continue;
}
// Get data for the key we're looking for.
Histogram* h = nullptr;
if (NS_FAILED(keyed->GetHistogram(mozilla::Get<1>(histogramData), &h))) {
continue;
}
MOZ_ASSERT(h);
if (!h || internal_IsExpired(locker, h)) {
// Don't restore expired histograms.
continue;
}
// Make sure that histogram counts have matching sizes. If not,
// |AddSampleSet| will fail and crash.
size_t numCounts = mozilla::Get<2>(histogramData).Length();
if (h->bucket_count() != numCounts) {
MOZ_ASSERT(false,
"The number of restored buckets does not match with the on in the definition");
continue;
}
// Update the data for the histogram.
h->AddSampleSet(base::PersistedSampleSet(std::move(mozilla::Get<2>(histogramData)),
mozilla::Get<3>(histogramData)));
}
}
}
return NS_OK;
}