Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 509 insertions, 0 deletions

diff --git a/xpcom/base/MemoryTelemetry.cpp b/xpcom/base/MemoryTelemetry.cpp
new file mode 100644
index 0000000000..5f34845a36
--- /dev/null
+++ b/xpcom/base/MemoryTelemetry.cpp
@@ -0,0 +1,509 @@
+/* -*- 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 "MemoryTelemetry.h"
+#include "nsMemoryReporterManager.h"
+
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/Result.h"
+#include "mozilla/ResultExtensions.h"
+#include "mozilla/Services.h"
+#include "mozilla/ScopeExit.h"
+#include "mozilla/SimpleEnumerator.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/TimeStamp.h"
+#include "mozilla/dom/ContentParent.h"
+#include "mozilla/dom/ScriptSettings.h"
+#include "nsContentUtils.h"
+#include "nsIBrowserDOMWindow.h"
+#include "nsIDOMChromeWindow.h"
+#include "nsIMemoryReporter.h"
+#include "nsIWindowMediator.h"
+#include "nsImportModule.h"
+#include "nsITelemetry.h"
+#include "nsNetCID.h"
+#include "nsObserverService.h"
+#include "nsReadableUtils.h"
+#include "nsThreadUtils.h"
+#include "nsXULAppAPI.h"
+#include "xpcpublic.h"
+
+#include <cstdlib>
+
+using namespace mozilla;
+
+using mozilla::dom::AutoJSAPI;
+using mozilla::dom::ContentParent;
+
+// Do not gather data more than once a minute (ms)
+static constexpr uint32_t kTelemetryInterval = 60 * 1000;
+
+static constexpr const char* kTopicCycleCollectorBegin =
+    "cycle-collector-begin";
+
+// How long to wait in millis for all the child memory reports to come in
+static constexpr uint32_t kTotalMemoryCollectorTimeout = 200;
+
+namespace {
+
+enum class PrevValue : uint32_t {
+#ifdef XP_WIN
+  LOW_MEMORY_EVENTS_VIRTUAL,
+  LOW_MEMORY_EVENTS_COMMIT_SPACE,
+  LOW_MEMORY_EVENTS_PHYSICAL,
+#endif
+#if defined(XP_LINUX) && !defined(ANDROID)
+  PAGE_FAULTS_HARD,
+#endif
+  SIZE_,
+};
+
+}  // anonymous namespace
+
+constexpr uint32_t kUninitialized = ~0;
+
+static uint32_t gPrevValues[uint32_t(PrevValue::SIZE_)];
+
+static uint32_t PrevValueIndex(Telemetry::HistogramID aId) {
+  switch (aId) {
+#ifdef XP_WIN
+    case Telemetry::LOW_MEMORY_EVENTS_VIRTUAL:
+      return uint32_t(PrevValue::LOW_MEMORY_EVENTS_VIRTUAL);
+    case Telemetry::LOW_MEMORY_EVENTS_COMMIT_SPACE:
+      return uint32_t(PrevValue::LOW_MEMORY_EVENTS_COMMIT_SPACE);
+    case Telemetry::LOW_MEMORY_EVENTS_PHYSICAL:
+      return uint32_t(PrevValue::LOW_MEMORY_EVENTS_PHYSICAL);
+#endif
+#if defined(XP_LINUX) && !defined(ANDROID)
+    case Telemetry::PAGE_FAULTS_HARD:
+      return uint32_t(PrevValue::PAGE_FAULTS_HARD);
+#endif
+    default:
+      MOZ_ASSERT_UNREACHABLE("Unexpected histogram ID");
+      return 0;
+  }
+}
+
+NS_IMPL_ISUPPORTS(MemoryTelemetry, nsIObserver, nsISupportsWeakReference)
+
+MemoryTelemetry::MemoryTelemetry()
+    : mThreadPool(do_GetService(NS_STREAMTRANSPORTSERVICE_CONTRACTID)) {}
+
+void MemoryTelemetry::Init() {
+  for (auto& val : gPrevValues) {
+    val = kUninitialized;
+  }
+
+  if (XRE_IsContentProcess()) {
+    nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+    MOZ_RELEASE_ASSERT(obs);
+
+    obs->AddObserver(this, "content-child-shutdown", true);
+  }
+}
+
+/* static */ MemoryTelemetry& MemoryTelemetry::Get() {
+  static RefPtr<MemoryTelemetry> sInstance;
+
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!sInstance) {
+    sInstance = new MemoryTelemetry();
+    sInstance->Init();
+    ClearOnShutdown(&sInstance);
+  }
+  return *sInstance;
+}
+
+nsresult MemoryTelemetry::DelayedInit() {
+  if (Telemetry::CanRecordExtended()) {
+    nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+    MOZ_RELEASE_ASSERT(obs);
+
+    obs->AddObserver(this, kTopicCycleCollectorBegin, true);
+  }
+
+  GatherReports();
+
+  return NS_OK;
+}
+
+nsresult MemoryTelemetry::Shutdown() {
+  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+  MOZ_RELEASE_ASSERT(obs);
+
+  obs->RemoveObserver(this, kTopicCycleCollectorBegin);
+
+  return NS_OK;
+}
+
+static inline void HandleMemoryReport(Telemetry::HistogramID aId,
+                                      int32_t aUnits, uint64_t aAmount,
+                                      const nsCString& aKey = VoidCString()) {
+  uint32_t val;
+  switch (aUnits) {
+    case nsIMemoryReporter::UNITS_BYTES:
+      val = uint32_t(aAmount / 1024);
+      break;
+
+    case nsIMemoryReporter::UNITS_PERCENTAGE:
+      // UNITS_PERCENTAGE amounts are 100x greater than their raw value.
+      val = uint32_t(aAmount / 100);
+      break;
+
+    case nsIMemoryReporter::UNITS_COUNT:
+      val = uint32_t(aAmount);
+      break;
+
+    case nsIMemoryReporter::UNITS_COUNT_CUMULATIVE: {
+      // If the reporter gives us a cumulative count, we'll report the
+      // difference in its value between now and our previous ping.
+
+      uint32_t idx = PrevValueIndex(aId);
+      uint32_t prev = gPrevValues[idx];
+      gPrevValues[idx] = aAmount;
+
+      if (prev == kUninitialized) {
+        // If this is the first time we're reading this reporter, store its
+        // current value but don't report it in the telemetry ping, so we
+        // ignore the effect startup had on the reporter.
+        return;
+      }
+      val = aAmount - prev;
+      break;
+    }
+
+    default:
+      MOZ_ASSERT_UNREACHABLE("Unexpected aUnits value");
+      return;
+  }
+
+  // Note: The reference equality check here should allow the compiler to
+  // optimize this case out at compile time when we weren't given a key,
+  // while IsEmpty() or IsVoid() most likely will not.
+  if (&aKey == &VoidCString()) {
+    Telemetry::Accumulate(aId, val);
+  } else {
+    Telemetry::Accumulate(aId, aKey, val);
+  }
+}
+
+nsresult MemoryTelemetry::GatherReports(
+    const std::function<void()>& aCompletionCallback) {
+  auto cleanup = MakeScopeExit([&]() {
+    if (aCompletionCallback) {
+      aCompletionCallback();
+    }
+  });
+
+  RefPtr<nsMemoryReporterManager> mgr = nsMemoryReporterManager::GetOrCreate();
+  MOZ_DIAGNOSTIC_ASSERT(mgr);
+  NS_ENSURE_TRUE(mgr, NS_ERROR_FAILURE);
+
+#define RECORD(id, metric, units)                                       \
+  do {                                                                  \
+    int64_t amt;                                                        \
+    nsresult rv = mgr->Get##metric(&amt);                               \
+    if (NS_SUCCEEDED(rv)) {                                             \
+      HandleMemoryReport(Telemetry::id, nsIMemoryReporter::units, amt); \
+    } else if (rv != NS_ERROR_NOT_AVAILABLE) {                          \
+      NS_WARNING("Failed to retrieve memory telemetry for " #metric);   \
+    }                                                                   \
+  } while (0)
+
+  // GHOST_WINDOWS is opt-out as of Firefox 55
+  RECORD(GHOST_WINDOWS, GhostWindows, UNITS_COUNT);
+
+  // If we're running in the parent process, collect data from all processes for
+  // the MEMORY_TOTAL histogram.
+  if (XRE_IsParentProcess() && !mTotalMemoryGatherer) {
+    mTotalMemoryGatherer = new TotalMemoryGatherer();
+    mTotalMemoryGatherer->Begin(mThreadPool);
+  }
+
+  if (!Telemetry::CanRecordReleaseData()) {
+    return NS_OK;
+  }
+
+  // Get memory measurements from distinguished amount attributes.  We used
+  // to measure "explicit" too, but it could cause hangs, and the data was
+  // always really noisy anyway.  See bug 859657.
+  //
+  // test_TelemetrySession.js relies on some of these histograms being
+  // here.  If you remove any of the following histograms from here, you'll
+  // have to modify test_TelemetrySession.js:
+  //
+  //   * MEMORY_TOTAL,
+  //   * MEMORY_JS_GC_HEAP, and
+  //   * MEMORY_JS_COMPARTMENTS_SYSTEM.
+  //
+  // The distinguished amount attribute names don't match the telemetry id
+  // names in some cases due to a combination of (a) historical reasons, and
+  // (b) the fact that we can't change telemetry id names without breaking
+  // data continuity.
+
+  // Collect cheap or main-thread only metrics synchronously, on the main
+  // thread.
+  RECORD(MEMORY_JS_GC_HEAP, JSMainRuntimeGCHeap, UNITS_BYTES);
+  RECORD(MEMORY_JS_COMPARTMENTS_SYSTEM, JSMainRuntimeCompartmentsSystem,
+         UNITS_COUNT);
+  RECORD(MEMORY_JS_COMPARTMENTS_USER, JSMainRuntimeCompartmentsUser,
+         UNITS_COUNT);
+  RECORD(MEMORY_JS_REALMS_SYSTEM, JSMainRuntimeRealmsSystem, UNITS_COUNT);
+  RECORD(MEMORY_JS_REALMS_USER, JSMainRuntimeRealmsUser, UNITS_COUNT);
+  RECORD(MEMORY_IMAGES_CONTENT_USED_UNCOMPRESSED, ImagesContentUsedUncompressed,
+         UNITS_BYTES);
+  RECORD(MEMORY_STORAGE_SQLITE, StorageSQLite, UNITS_BYTES);
+#ifdef XP_WIN
+  RECORD(LOW_MEMORY_EVENTS_VIRTUAL, LowMemoryEventsVirtual,
+         UNITS_COUNT_CUMULATIVE);
+  RECORD(LOW_MEMORY_EVENTS_COMMIT_SPACE, LowMemoryEventsCommitSpace,
+         UNITS_COUNT_CUMULATIVE);
+  RECORD(LOW_MEMORY_EVENTS_PHYSICAL, LowMemoryEventsPhysical,
+         UNITS_COUNT_CUMULATIVE);
+#endif
+#if defined(XP_LINUX) && !defined(ANDROID)
+  RECORD(PAGE_FAULTS_HARD, PageFaultsHard, UNITS_COUNT_CUMULATIVE);
+#endif
+
+  RefPtr<Runnable> completionRunnable;
+  if (aCompletionCallback) {
+    completionRunnable = NS_NewRunnableFunction(__func__, aCompletionCallback);
+  }
+
+  // Collect expensive metrics that can be calculated off-main-thread
+  // asynchronously, on a background thread.
+  RefPtr<Runnable> runnable = NS_NewRunnableFunction(
+      "MemoryTelemetry::GatherReports", [mgr, completionRunnable]() mutable {
+        RECORD(MEMORY_VSIZE, Vsize, UNITS_BYTES);
+#if !defined(HAVE_64BIT_BUILD) || !defined(XP_WIN)
+        RECORD(MEMORY_VSIZE_MAX_CONTIGUOUS, VsizeMaxContiguous, UNITS_BYTES);
+#endif
+        RECORD(MEMORY_RESIDENT_FAST, ResidentFast, UNITS_BYTES);
+        RECORD(MEMORY_RESIDENT_PEAK, ResidentPeak, UNITS_BYTES);
+        RECORD(MEMORY_UNIQUE, ResidentUnique, UNITS_BYTES);
+        RECORD(MEMORY_HEAP_ALLOCATED, HeapAllocated, UNITS_BYTES);
+        RECORD(MEMORY_HEAP_OVERHEAD_FRACTION, HeapOverheadFraction,
+               UNITS_PERCENTAGE);
+
+        if (completionRunnable) {
+          NS_DispatchToMainThread(completionRunnable.forget(),
+                                  NS_DISPATCH_NORMAL);
+        }
+      });
+
+#undef RECORD
+
+  nsresult rv = mThreadPool->Dispatch(runnable.forget(), NS_DISPATCH_NORMAL);
+  if (!NS_WARN_IF(NS_FAILED(rv))) {
+    cleanup.release();
+  }
+
+  return NS_OK;
+}
+
+NS_IMPL_ISUPPORTS(MemoryTelemetry::TotalMemoryGatherer, nsITimerCallback)
+
+/**
+ * Polls all child processes for their unique set size, and populates the
+ * MEMORY_TOTAL and MEMORY_DISTRIBUTION_AMONG_CONTENT histograms with the
+ * results.
+ */
+void MemoryTelemetry::TotalMemoryGatherer::Begin(nsIEventTarget* aThreadPool) {
+  nsCOMPtr<nsISerialEventTarget> target = GetMainThreadSerialEventTarget();
+
+  nsTArray<ContentParent*> parents;
+  ContentParent::GetAll(parents);
+  for (auto& parent : parents) {
+    mRemainingChildCount++;
+    parent->SendGetMemoryUniqueSetSize()->Then(
+        target, "TotalMemoryGather::Begin", this,
+        &TotalMemoryGatherer::CollectResult, &TotalMemoryGatherer::OnFailure);
+  }
+
+  mChildSizes.SetCapacity(mRemainingChildCount);
+
+  RefPtr<TotalMemoryGatherer> self{this};
+
+  aThreadPool->Dispatch(
+      NS_NewRunnableFunction(
+          "TotalMemoryGather::Begin",
+          [self]() {
+            RefPtr<nsMemoryReporterManager> mgr =
+                nsMemoryReporterManager::GetOrCreate();
+            MOZ_RELEASE_ASSERT(mgr);
+
+            NS_DispatchToMainThread(NewRunnableMethod<int64_t>(
+                "TotalMemoryGather::CollectParentSize", self,
+                &TotalMemoryGatherer::CollectParentSize, mgr->ResidentFast()));
+          }),
+      NS_DISPATCH_NORMAL);
+
+  NS_NewTimerWithCallback(getter_AddRefs(mTimeout), this,
+                          kTotalMemoryCollectorTimeout,
+                          nsITimer::TYPE_ONE_SHOT);
+}
+
+nsresult MemoryTelemetry::TotalMemoryGatherer::MaybeFinish() {
+  // If we timed out waiting for a response from any child, we don't report
+  // anything for this attempt.
+  if (!mTimeout || !mHaveParentSize || mRemainingChildCount) {
+    return NS_OK;
+  }
+
+  mTimeout = nullptr;
+  MemoryTelemetry::Get().mTotalMemoryGatherer = nullptr;
+
+  HandleMemoryReport(Telemetry::MEMORY_TOTAL, nsIMemoryReporter::UNITS_BYTES,
+                     mTotalMemory);
+
+  if (mChildSizes.Length() > 1) {
+    int32_t tabsCount;
+    MOZ_TRY_VAR(tabsCount, GetOpenTabsCount());
+
+    nsCString key;
+    if (tabsCount <= 10) {
+      key = "0 - 10 tabs";
+    } else if (tabsCount <= 500) {
+      key = "11 - 500 tabs";
+    } else {
+      key = "more tabs";
+    }
+
+    // Mean of the USS of all the content processes.
+    int64_t mean = 0;
+    for (auto size : mChildSizes) {
+      mean += size;
+    }
+    mean /= mChildSizes.Length();
+
+    // For some users, for unknown reasons (though most likely because they're
+    // in a sandbox without procfs mounted), we wind up with 0 here, which
+    // triggers a floating point exception if we try to calculate values using
+    // it.
+    if (!mean) {
+      return NS_ERROR_UNEXPECTED;
+    }
+
+    // Absolute error of USS for each content process, normalized by the mean
+    // (*100 to get it in percentage). 20% means for a content process that it
+    // is using 20% more or 20% less than the mean.
+    for (auto size : mChildSizes) {
+      int64_t diff = llabs(size - mean) * 100 / mean;
+
+      HandleMemoryReport(Telemetry::MEMORY_DISTRIBUTION_AMONG_CONTENT,
+                         nsIMemoryReporter::UNITS_COUNT, diff, key);
+    }
+  }
+
+  // This notification is for testing only.
+  if (nsCOMPtr<nsIObserverService> obs = services::GetObserverService()) {
+    obs->NotifyObservers(nullptr, "gather-memory-telemetry-finished", nullptr);
+  }
+
+  return NS_OK;
+}
+
+void MemoryTelemetry::TotalMemoryGatherer::CollectParentSize(
+    int64_t aResident) {
+  mTotalMemory += aResident;
+  mHaveParentSize = true;
+
+  MaybeFinish();
+}
+
+void MemoryTelemetry::TotalMemoryGatherer::CollectResult(int64_t aChildUSS) {
+  mChildSizes.AppendElement(aChildUSS);
+
+  mTotalMemory += aChildUSS;
+  mRemainingChildCount--;
+
+  MaybeFinish();
+}
+
+void MemoryTelemetry::TotalMemoryGatherer::OnFailure(
+    mozilla::ipc::ResponseRejectReason aReason) {
+  // Treat failure of any request the same as a timeout.
+  Notify(nullptr);
+}
+
+nsresult MemoryTelemetry::TotalMemoryGatherer::Notify(nsITimer* aTimer) {
+  // Set mTimeout null to indicate the timeout has fired. After this, all
+  // results for this attempt will be ignored.
+  mTimeout = nullptr;
+  MemoryTelemetry::Get().mTotalMemoryGatherer = nullptr;
+  return NS_OK;
+}
+
+/* static */ Result<uint32_t, nsresult> MemoryTelemetry::GetOpenTabsCount() {
+  nsresult rv;
+
+  nsCOMPtr<nsIWindowMediator> windowMediator(
+      do_GetService(NS_WINDOWMEDIATOR_CONTRACTID, &rv));
+  MOZ_TRY(rv);
+
+  nsCOMPtr<nsISimpleEnumerator> enumerator;
+  MOZ_TRY(windowMediator->GetEnumerator(u"navigator:browser",
+                                        getter_AddRefs(enumerator)));
+
+  uint32_t total = 0;
+  for (auto& window : SimpleEnumerator<nsIDOMChromeWindow>(enumerator)) {
+    nsCOMPtr<nsIBrowserDOMWindow> browserWin;
+    MOZ_TRY(window->GetBrowserDOMWindow(getter_AddRefs(browserWin)));
+
+    NS_ENSURE_TRUE(browserWin, Err(NS_ERROR_UNEXPECTED));
+
+    uint32_t tabCount;
+    MOZ_TRY(browserWin->GetTabCount(&tabCount));
+    total += tabCount;
+  }
+
+  return total;
+}
+
+void MemoryTelemetry::GetUniqueSetSize(
+    std::function<void(const int64_t&)>&& aCallback) {
+  mThreadPool->Dispatch(
+      NS_NewRunnableFunction(
+          "MemoryTelemetry::GetUniqueSetSize",
+          [callback = std::move(aCallback)]() mutable {
+            RefPtr<nsMemoryReporterManager> mgr =
+                nsMemoryReporterManager::GetOrCreate();
+            MOZ_RELEASE_ASSERT(mgr);
+
+            int64_t uss = mgr->ResidentUnique();
+
+            NS_DispatchToMainThread(NS_NewRunnableFunction(
+                "MemoryTelemetry::GetUniqueSetSizeResult",
+                [uss, callback = std::move(callback)]() { callback(uss); }));
+          }),
+      NS_DISPATCH_NORMAL);
+}
+
+nsresult MemoryTelemetry::Observe(nsISupports* aSubject, const char* aTopic,
+                                  const char16_t* aData) {
+  if (strcmp(aTopic, kTopicCycleCollectorBegin) == 0) {
+    auto now = TimeStamp::Now();
+    if (!mLastPoll.IsNull() &&
+        (now - mLastPoll).ToMilliseconds() < kTelemetryInterval) {
+      return NS_OK;
+    }
+
+    mLastPoll = now;
+
+    NS_DispatchToCurrentThreadQueue(
+        NewRunnableMethod<std::function<void()>>(
+            "MemoryTelemetry::GatherReports", this,
+            &MemoryTelemetry::GatherReports, nullptr),
+        EventQueuePriority::Idle);
+  } else if (strcmp(aTopic, "content-child-shutdown") == 0) {
+    if (nsCOMPtr<nsITelemetry> telemetry =
+            do_GetService("@mozilla.org/base/telemetry;1")) {
+      telemetry->FlushBatchedChildTelemetry();
+    }
+  }
+  return NS_OK;
+}