Backed out 2 changesets (bug 1280629) for wpt failures on media-elements/video_008.htm

Backed out changeset 64648fd6ef5e (bug 1280629)
Backed out changeset e654f2b128f6 (bug 1280629)

modules/libpref/init/all.js

@@ -1816,10 +1816,6 @@ pref("network.http.rcwn.max_wait_before_racing_ms", 500);
 // all available active connections.
 pref("network.http.focused_window_transaction_ratio", "0.9");
 
-// This is the size of the flow control window (KB) (i.e., the amount of data
-// that the parent can send to the child before getting an ack)
-pref("network.http.send_window_size", 1024);
-
 // Whether or not we give more priority to active tab.
 // Note that this requires restart for changes to take effect.
 #ifdef ANDROID

netwerk/protocol/http/HttpChannelChild.cpp

@@ -920,50 +920,6 @@ HttpChannelChild::OnTransportAndData(const nsresult& channelStatus,
 
   DoOnDataAvailable(this, mListenerContext, stringStream, offset, count);
   stringStream->Close();
-
-  if (NeedToReportBytesRead()) {
-    mUnreportBytesRead += count;
-    if (mUnreportBytesRead >= gHttpHandler->SendWindowSize() >> 2) {
-      if (NS_IsMainThread()) {
-        Unused << SendBytesRead(mUnreportBytesRead);
-      } else {
-        // PHttpChannel connects to the main thread
-        RefPtr<HttpChannelChild> self = this;
-        int32_t bytesRead = mUnreportBytesRead;
-        nsCOMPtr<nsIEventTarget> neckoTarget = GetNeckoTarget();
-        MOZ_ASSERT(neckoTarget);
-
-        DebugOnly<nsresult> rv = neckoTarget->Dispatch(
-          NS_NewRunnableFunction("net::HttpChannelChild::SendBytesRead",
-                                 [self, bytesRead]() {
-                                   Unused << self->SendBytesRead(bytesRead);
-                                 }),
-          NS_DISPATCH_NORMAL);
-        MOZ_ASSERT(NS_SUCCEEDED(rv));
-      }
-      mUnreportBytesRead = 0;
-    }
-  }
-}
-
-bool
-HttpChannelChild::NeedToReportBytesRead() {
- if (mCacheNeedToReportBytesReadInitialized) {
-    return mNeedToReportBytesRead;
-  }
-
-  // Might notify parent for partial cache, and the IPC message is ignored by
-  // parent.
-  int64_t contentLength = -1;
-  if (gHttpHandler->SendWindowSize() == 0 ||
-      mIsFromCache ||
-      NS_FAILED(GetContentLength(&contentLength)) ||
-      contentLength < gHttpHandler->SendWindowSize()) {
-    mNeedToReportBytesRead = false;
-  }
-
-  mCacheNeedToReportBytesReadInitialized = true;
-  return mNeedToReportBytesRead;
 }
 
 void

netwerk/protocol/http/HttpChannelChild.h

@@ -258,12 +258,6 @@ private:
                                        const nsCString& aProvider,
                                        const nsCString& aFullHash);
 
-  // Return true if we need to tell the parent the size of unreported received
-  // data
-  bool NeedToReportBytesRead();
-  bool mCacheNeedToReportBytesReadInitialized = false;
-  bool mNeedToReportBytesRead = true;
-  int32_t mUnreportBytesRead = 0;
 
   void DoOnStartRequest(nsIRequest* aRequest, nsISupports* aContext);
   void DoOnStatus(nsIRequest* aRequest, nsresult status);

netwerk/protocol/http/HttpChannelParent.cpp

@@ -73,7 +73,6 @@ HttpChannelParent::HttpChannelParent(const PBrowserOrId& iframeEmbedding,
   , mIgnoreProgress(false)
   , mSentRedirect1BeginFailed(false)
   , mReceivedRedirect2Verify(false)
-  , mHasSuspendedByBackPressure(false)
   , mPendingDiversion(false)
   , mDivertingFromChild(false)
   , mDivertedOnStartRequest(false)
@@ -96,8 +95,6 @@ HttpChannelParent::HttpChannelParent(const PBrowserOrId& iframeEmbedding,
     mNestedFrameId = iframeEmbedding.get_TabId();
   }
 
-  mSendWindowSize = gHttpHandler->SendWindowSize();
-
   mEventQ = new ChannelEventQueue(static_cast<nsIParentRedirectingChannel*>(this));
 }
 
@@ -1586,10 +1583,6 @@ HttpChannelParent::OnStopRequest(nsIRequest *aRequest,
     return NS_ERROR_UNEXPECTED;
   }
 
-  if (NeedFlowControl()) {
-    Telemetry::Accumulate(Telemetry::NETWORK_BACK_PRESSURE_SUSPENSION_RATE, mHasSuspendedByBackPressure);
-  }
-
   return NS_OK;
 }
 
@@ -1629,8 +1622,6 @@ HttpChannelParent::OnDataAvailable(nsIRequest *aRequest,
     return NS_ERROR_OUT_OF_MEMORY;
   }
 
-  int32_t count = static_cast<int32_t>(aCount);
-
   while (aCount) {
     nsresult rv = NS_ReadInputStreamToString(aInputStream, data, toRead);
     if (NS_FAILED(rv)) {
@@ -1652,66 +1643,9 @@ HttpChannelParent::OnDataAvailable(nsIRequest *aRequest,
     toRead = std::min<uint32_t>(aCount, kCopyChunkSize);
   }
 
-  if (NeedFlowControl()) {
-    // We're going to run out of sending window size
-    if (mSendWindowSize > 0 && mSendWindowSize <= count) {
-      MOZ_ASSERT(!mSuspendedForFlowControl);
-      Unused << mChannel->Suspend();
-      mSuspendedForFlowControl = true;
-      mHasSuspendedByBackPressure = true;
-    }
-    mSendWindowSize -= count;
-  }
-
   return NS_OK;
 }
 
-bool
-HttpChannelParent::NeedFlowControl()
-{
-  if (mCacheNeedFlowControlInitialized) {
-    return mNeedFlowControl;
-  }
-
-  int64_t contentLength = -1;
-
-  RefPtr<nsHttpChannel> httpChannelImpl = do_QueryObject(mChannel);
-
-  // By design, we won't trigger the flow control if
-  // a. pref-out
-  // b. the resource is from cache or partial cache
-  // c. the resource is small
-  // Note that we served the cached resource first for partical cache, which is
-  // ignored here since we only take the first ODA into consideration.
-  if (gHttpHandler->SendWindowSize() == 0 ||
-      !httpChannelImpl ||
-      httpChannelImpl->IsReadingFromCache() ||
-      NS_FAILED(httpChannelImpl->GetContentLength(&contentLength)) ||
-      contentLength < gHttpHandler->SendWindowSize()) {
-    mNeedFlowControl = false;
-  }
-  mCacheNeedFlowControlInitialized = true;
-  return mNeedFlowControl;
-}
-
-mozilla::ipc::IPCResult
-HttpChannelParent::RecvBytesRead(const int32_t& aCount)
-{
-  if (!NeedFlowControl()) {
-    return IPC_OK();
-  }
-
-  LOG(("HttpBackgroundChannelParent::RecvBytesRead [this=%p count=%" PRId32 "]\n", this, aCount));
-
-  if (mSendWindowSize <= 0 && mSendWindowSize + aCount > 0) {
-    MOZ_ASSERT(mSuspendedForFlowControl);
-    Unused << mChannel->Resume();
-    mSuspendedForFlowControl = false;
-  }
-  mSendWindowSize += aCount;
-  return IPC_OK();
-}
-
 //-----------------------------------------------------------------------------
 // HttpChannelParent::nsIProgressEventSink
 //-----------------------------------------------------------------------------

netwerk/protocol/http/HttpChannelParent.h

@@ -209,7 +209,6 @@ protected:
   virtual mozilla::ipc::IPCResult RecvDivertComplete() override;
   virtual mozilla::ipc::IPCResult RecvRemoveCorsPreflightCacheEntry(const URIParams& uri,
                                                                     const mozilla::ipc::PrincipalInfo& requestingPrincipal) override;
-  virtual mozilla::ipc::IPCResult RecvBytesRead(const int32_t& aCount) override;
   virtual void ActorDestroy(ActorDestroyReason why) override;
 
   // Supporting function for ADivertableParentChannel.
@@ -263,15 +262,6 @@ private:
   // DocumentChannelCleanup.
   void CleanupBackgroundChannel();
 
-  // Check if the channel needs to enable the flow control on the IPC channel.
-  // That is, we may suspend the channel if the ODA-s to child process are not
-  // consumed quickly enough. Otherwise, memory explosion could happen.
-  bool NeedFlowControl();
-  bool mCacheNeedFlowControlInitialized = false;
-  bool mNeedFlowControl = true;
-  bool mSuspendedForFlowControl = false;
-  int32_t mSendWindowSize;
-
   friend class HttpBackgroundChannelParent;
   friend class DivertDataAvailableEvent;
   friend class DivertStopRequestEvent;
@@ -319,7 +309,6 @@ private:
 
   uint8_t mSentRedirect1BeginFailed    : 1;
   uint8_t mReceivedRedirect2Verify     : 1;
-  uint8_t mHasSuspendedByBackPressure  : 1;
 
   // Indicates that diversion has been requested, but we could not start it
   // yet because the channel is still being opened with a synthesized response.

netwerk/protocol/http/PHttpChannel.ipdl

@@ -91,10 +91,6 @@ parent:
   // sure not to send any more messages after that.
   async DeletingChannel();
 
-  // Tell the parent the amount bytes read by child for the e10s back pressure
-  // flow control
-  async BytesRead(int32_t count);
-
   async __delete__();
 
 child:

netwerk/protocol/http/nsHttpHandler.cpp

@@ -221,7 +221,6 @@ nsHttpHandler::nsHttpHandler()
     , mThrottleReadInterval(500)
     , mThrottleHoldTime(600)
     , mThrottleMaxTime(3000)
-    , mSendWindowSize(1024)
     , mUrgentStartEnabled(true)
     , mTailBlockingEnabled(true)
     , mTailDelayQuantum(600)
@@ -1746,11 +1745,6 @@ nsHttpHandler::PrefsChanged(const char *pref)
       }
     }
 
-    if (PREF_CHANGED(HTTP_PREF("send_window_size"))) {
-      Unused << Preferences::GetInt(HTTP_PREF("send_window_size"), &val);
-      mSendWindowSize = val >= 0 ? val : 0;
-    }
-
     if (PREF_CHANGED(HTTP_PREF("on_click_priority"))) {
         Unused << Preferences::GetBool(HTTP_PREF("on_click_priority"), &mUrgentStartEnabled);
     }

netwerk/protocol/http/nsHttpHandler.h

@@ -148,7 +148,6 @@ public:
     uint32_t       TailBlockingTotalMax() { return mTailTotalMax; }
 
     uint32_t       ThrottlingReadLimit() { return mThrottleVersion == 1 ? 0 : mThrottleReadLimit; }
-    int32_t        SendWindowSize() { return mSendWindowSize * 1024; }
 
     // TCP Keepalive configuration values.
 
@@ -503,8 +502,6 @@ private:
     uint32_t mThrottleHoldTime;
     uint32_t mThrottleMaxTime;
 
-    int32_t mSendWindowSize;
-
     bool mUrgentStartEnabled;
     bool mTailBlockingEnabled;
     uint32_t mTailDelayQuantum;

testing/web-platform/meta/2dcontext/imagebitmap/createImageBitmap-origin.sub.html.ini

@@ -1,5 +1,4 @@
 [createImageBitmap-origin.sub.html]
-  prefs: [network.http.send_window_size:0]
   [cross-origin HTMLImageElement]
     expected: FAIL
 

testing/web-platform/meta/html/semantics/embedded-content/media-elements/playing-the-media-resource/pause-move-to-other-document.html.ini

@@ -1,3 +1,2 @@
 [pause-move-to-other-document.html]
   max-asserts: 103
-  prefs: [network.http.send_window_size:0]

testing/web-platform/meta/html/semantics/embedded-content/the-video-element/video_initially_paused.html.ini

@@ -1,3 +1,2 @@
 [video_initially_paused.html]
   expected: FAIL
-  prefs: [network.http.send_window_size:0]

toolkit/components/telemetry/Histograms.json

@@ -1954,14 +1954,6 @@
     "labels": ["NotSent", "CachedContentUsed", "CachedContentNotUsed"],
     "description": "Stats for validation requests when cache won the race."
   },
-  "NETWORK_BACK_PRESSURE_SUSPENSION_RATE": {
-    "record_in_processes": ["main"],
-    "expires_in_version": "68",
-    "alert_emails": ["necko@mozilla.com", "junior@mozilla.com"],
-    "bug_numbers": [1280629],
-    "kind": "boolean",
-    "description": "Collect whether the flow control to enable e10s back pressure triggers the suspension (true) or not (false)"
-  },
   "NETWORK_HTTP_REDIRECT_TO_SCHEME" :{
     "record_in_processes": ["main"],
     "alert_emails": ["necko@mozilla.com", "seceng-telemetry@mozilla.com", "jkt@mozilla.com"],