Changeset 207812 in webkit

Timestamp:

Oct 25, 2016 1:22:19 AM (7 years ago)

Author:

Antti Koivisto

Message:

Add support for introducing simulated latency in network process
​https://bugs.webkit.org/show_bug.cgi?id=163902

Reviewed by Alex Christensen.

For testing purposes it is useful to have a mechanism for simulating high latency.
This patch adds a basic mechanism that introduces a delay to each response in network
process. In Safari it can be used with

defaults write com.apple.Safari WebKitNetworkLoadThrottleLatencyMilliseconds 200

Setting the delay to 0 disables the feature.

• NetworkProcess/NetworkLoad.cpp:

(WebKit::NetworkLoad::Throttle::Throttle):
(WebKit::NetworkLoad::didReceiveResponseNetworkSession):
(WebKit::NetworkLoad::notifyDidReceiveResponse):
(WebKit::NetworkLoad::didReceiveData):
(WebKit::NetworkLoad::didCompleteWithError):
(WebKit::NetworkLoad::throttleDelayCompleted):

• NetworkProcess/NetworkLoad.h:
• NetworkProcess/NetworkProcess.cpp:

(WebKit::NetworkProcess::initializeNetworkProcess):

• NetworkProcess/NetworkProcess.h:

(WebKit::NetworkProcess::loadThrottleLatency):

• NetworkProcess/NetworkProcessCreationParameters.cpp:

(WebKit::NetworkProcessCreationParameters::encode):
(WebKit::NetworkProcessCreationParameters::decode):

• NetworkProcess/NetworkProcessCreationParameters.h:
• UIProcess/Cocoa/WebProcessPoolCocoa.mm:

(WebKit::WebProcessPool::platformInitializeNetworkProcess):

Location:

trunk/Source/WebKit2

Files:

• ChangeLog (modified) (1 diff)
• NetworkProcess/NetworkLoad.cpp (modified) (3 diffs)
• NetworkProcess/NetworkLoad.h (modified) (2 diffs)
• NetworkProcess/NetworkProcess.cpp (modified) (1 diff)
• NetworkProcess/NetworkProcess.h (modified) (2 diffs)
• NetworkProcess/NetworkProcessCreationParameters.cpp (modified) (2 diffs)
• NetworkProcess/NetworkProcessCreationParameters.h (modified) (1 diff)
• UIProcess/Cocoa/WebProcessPoolCocoa.mm (modified) (2 diffs)

trunk/Source/WebKit2/ChangeLog

@@ +1 @@
+2016-10-25  Antti Koivisto  <antti@apple.com>
+
+        Add support for introducing simulated latency in network process
+        https://bugs.webkit.org/show_bug.cgi?id=163902
+
+        Reviewed by Alex Christensen.
+
+        For testing purposes it is useful to have a mechanism for simulating high latency.
+        This patch adds a basic mechanism that introduces a delay to each response in network
+        process. In Safari it can be used with
+
+             defaults write com.apple.Safari WebKitNetworkLoadThrottleLatencyMilliseconds 200
+
+        Setting the delay to 0 disables the feature.
+
+        * NetworkProcess/NetworkLoad.cpp:
+        (WebKit::NetworkLoad::Throttle::Throttle):
+        (WebKit::NetworkLoad::didReceiveResponseNetworkSession):
+        (WebKit::NetworkLoad::notifyDidReceiveResponse):
+        (WebKit::NetworkLoad::didReceiveData):
+        (WebKit::NetworkLoad::didCompleteWithError):
+        (WebKit::NetworkLoad::throttleDelayCompleted):
+        * NetworkProcess/NetworkLoad.h:
+        * NetworkProcess/NetworkProcess.cpp:
+        (WebKit::NetworkProcess::initializeNetworkProcess):
+        * NetworkProcess/NetworkProcess.h:
+        (WebKit::NetworkProcess::loadThrottleLatency):
+        * NetworkProcess/NetworkProcessCreationParameters.cpp:
+        (WebKit::NetworkProcessCreationParameters::encode):
+        (WebKit::NetworkProcessCreationParameters::decode):
+        * NetworkProcess/NetworkProcessCreationParameters.h:
+        * UIProcess/Cocoa/WebProcessPoolCocoa.mm:
+        (WebKit::WebProcessPool::platformInitializeNetworkProcess):
+
 2016-10-24  Dan Bernstein  <mitz@apple.com>
 

trunk/Source/WebKit2/NetworkProcess/NetworkLoad.cpp

@@ -46 +46 @@
 #if USE(NETWORK_SESSION)
 
+struct NetworkLoad::Throttle {
+    Throttle(NetworkLoad& load, std::chrono::milliseconds delay, ResourceResponse&& response, ResponseCompletionHandler&& handler)
+        : timer(load, &NetworkLoad::throttleDelayCompleted)
+        , response(WTFMove(response))
+        , responseCompletionHandler(WTFMove(handler))
+    {
+        timer.startOneShot(delay);
+    }
+    Timer timer;
+    ResourceResponse response;
+    ResponseCompletionHandler responseCompletionHandler;
+};
+
 NetworkLoad::NetworkLoad(NetworkLoadClient& client, NetworkLoadParameters&& parameters, NetworkSession& networkSession)
     : m_client(client)
@@ -272 +285 @@
 {
     ASSERT(isMainThread());
-    if (m_task && m_task->isDownload())
+    ASSERT(!m_throttle);
+
+    if (m_task && m_task->isDownload()) {
         NetworkProcess::singleton().findPendingDownloadLocation(*m_task.get(), WTFMove(completionHandler), response);
-    else if (sharedDidReceiveResponse(WTFMove(response)) == NetworkLoadClient::ShouldContinueDidReceiveResponse::Yes)
-        completionHandler(PolicyUse);
-    else
+        return;
+    }
+
+    auto delay = NetworkProcess::singleton().loadThrottleLatency();
+    if (delay > 0ms) {
+        m_throttle = std::make_unique<Throttle>(*this, delay, WTFMove(response), WTFMove(completionHandler));
+        return;
+    }
+
+    notifyDidReceiveResponse(WTFMove(response), WTFMove(completionHandler));
+}
+
+void NetworkLoad::notifyDidReceiveResponse(ResourceResponse&& response, ResponseCompletionHandler&& completionHandler)
+{
+    ASSERT(isMainThread());
+
+    if (sharedDidReceiveResponse(WTFMove(response)) == NetworkLoadClient::ShouldContinueDidReceiveResponse::No) {
         m_responseCompletionHandler = WTFMove(completionHandler);
+        return;
+    }
+    completionHandler(PolicyUse);
 }
 
 void NetworkLoad::didReceiveData(Ref<SharedBuffer>&& buffer)
 {
+    ASSERT(!m_throttle);
+
     // FIXME: This should be the encoded data length, not the decoded data length.
     auto size = buffer->size();
@@ -289 +323 @@
 void NetworkLoad::didCompleteWithError(const ResourceError& error)
 {
+    ASSERT(!m_throttle);
+
     if (error.isNull())
         m_client.didFinishLoading(WTF::monotonicallyIncreasingTime());
     else
         m_client.didFailLoading(error);
+}
+
+void NetworkLoad::throttleDelayCompleted()
+{
+    ASSERT(m_throttle);
+
+    auto throttle = WTFMove(m_throttle);
+
+    notifyDidReceiveResponse(WTFMove(throttle->response), WTFMove(throttle->responseCompletionHandler));
 }
 

trunk/Source/WebKit2/NetworkProcess/NetworkLoad.h

@@ -125 +125 @@
     void cannotShowURL() final;
 
+    void notifyDidReceiveResponse(WebCore::ResourceResponse&&, ResponseCompletionHandler&&);
+    void throttleDelayCompleted();
+
     void completeAuthenticationChallenge(ChallengeCompletionHandler&&);
 #endif
@@ -138 +141 @@
     ResponseCompletionHandler m_responseCompletionHandler;
     RedirectCompletionHandler m_redirectCompletionHandler;
+    
+    struct Throttle;
+    std::unique_ptr<Throttle> m_throttle;
 #else
     bool m_waitingForContinueCanAuthenticateAgainstProtectionSpace { false };

trunk/Source/WebKit2/NetworkProcess/NetworkProcess.cpp

@@ -206 +206 @@
 
     m_suppressMemoryPressureHandler = parameters.shouldSuppressMemoryPressureHandler;
+    m_loadThrottleLatency = parameters.loadThrottleLatency;
     if (!m_suppressMemoryPressureHandler) {
         auto& memoryPressureHandler = MemoryPressureHandler::singleton();

trunk/Source/WebKit2/NetworkProcess/NetworkProcess.h

@@ -121 +121 @@
     void grantSandboxExtensionsToDatabaseProcessForBlobs(const Vector<String>& filenames, Function<void ()>&& completionHandler);
 
+    std::chrono::milliseconds loadThrottleLatency() const { return m_loadThrottleLatency; }
+
 private:
     NetworkProcess();
@@ -211 +213 @@
     bool m_diskCacheIsDisabledForTesting;
     bool m_canHandleHTTPSServerTrustEvaluation;
+    std::chrono::milliseconds m_loadThrottleLatency;
 
     typedef HashMap<const char*, std::unique_ptr<NetworkProcessSupplement>, PtrHash<const char*>> NetworkProcessSupplementMap;

trunk/Source/WebKit2/NetworkProcess/NetworkProcessCreationParameters.cpp

@@ -65 +65 @@
     encoder << shouldUseTestingNetworkSession;
     encoder << urlParserEnabled;
+    encoder << loadThrottleLatency;
     encoder << urlSchemesRegisteredForCustomProtocols;
 #if PLATFORM(COCOA)
@@ -137 +138 @@
     if (!decoder.decode(result.urlParserEnabled))
         return false;
+    if (!decoder.decode(result.loadThrottleLatency))
+        return false;
     if (!decoder.decode(result.urlSchemesRegisteredForCustomProtocols))
         return false;

trunk/Source/WebKit2/NetworkProcess/NetworkProcessCreationParameters.h

@@ -74 +74 @@
     bool shouldUseTestingNetworkSession;
     bool urlParserEnabled { false };
+    std::chrono::milliseconds loadThrottleLatency;
 
     Vector<String> urlSchemesRegisteredForCustomProtocols;

trunk/Source/WebKit2/UIProcess/Cocoa/WebProcessPoolCocoa.mm

@@ -84 +84 @@
 
 static NSString * const WebKitSuppressMemoryPressureHandlerDefaultsKey = @"WebKitSuppressMemoryPressureHandler";
+static NSString * const WebKitNetworkLoadThrottleLatencyMillisecondsDefaultsKey = @"WebKitNetworkLoadThrottleLatencyMilliseconds";
 
 static NSString * const WebKitVariationFontsEnabledDefaultsKey = @"ExperimentalVariationFontsEnabled";
@@ -253 +254 @@
 
     parameters.shouldSuppressMemoryPressureHandler = [defaults boolForKey:WebKitSuppressMemoryPressureHandlerDefaultsKey];
+    parameters.loadThrottleLatency = std::chrono::milliseconds([defaults integerForKey:WebKitNetworkLoadThrottleLatencyMillisecondsDefaultsKey]);
 
 #if PLATFORM(MAC) && __MAC_OS_X_VERSION_MIN_REQUIRED >= 101100