[iOS] WebProcess::initializeWebProcess spends ~150ms spinning up AVSy…

…stemController on some devices

https://bugs.webkit.org/show_bug.cgi?id=178640
<rdar://problem/35113105>

Reviewed by Youenn Fablet.

In r213933, we added a mechanism to allow the web process to drive media capture, by setting an attribute on the
shared AVSystemController. This requires us to fault in the Celestial framework, which is a slight performance
hit on some hardware. Instead of doing this at the start of every web process launch, we can just do this work
lazily, the first time the web process requests permissions for user media access.

* WebProcess/WebCoreSupport/WebUserMediaClient.cpp:
(WebKit::WebUserMediaClient::requestUserMediaAccess):
* WebProcess/WebPage/WebPage.cpp:
(WebKit::WebPage::prepareToSendUserMediaPermissionRequest):
* WebProcess/WebPage/WebPage.h:
* WebProcess/WebPage/ios/WebPageIOS.mm:
(WebKit::WebPage::prepareToSendUserMediaPermissionRequest):
* WebProcess/cocoa/WebProcessCocoa.mm:
(WebKit::WebProcess::platformInitializeWebProcess):


Canonical link: https://commits.webkit.org/194825@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@223827 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebKit/ChangeLog

@@ -1,3 +1,26 @@
+2017-10-22  Wenson Hsieh  <wenson_hsieh@apple.com>
+
+        [iOS] WebProcess::initializeWebProcess spends ~150ms spinning up AVSystemController on some devices
+        https://bugs.webkit.org/show_bug.cgi?id=178640
+        <rdar://problem/35113105>
+
+        Reviewed by Youenn Fablet.
+
+        In r213933, we added a mechanism to allow the web process to drive media capture, by setting an attribute on the
+        shared AVSystemController. This requires us to fault in the Celestial framework, which is a slight performance
+        hit on some hardware. Instead of doing this at the start of every web process launch, we can just do this work
+        lazily, the first time the web process requests permissions for user media access.
+
+        * WebProcess/WebCoreSupport/WebUserMediaClient.cpp:
+        (WebKit::WebUserMediaClient::requestUserMediaAccess):
+        * WebProcess/WebPage/WebPage.cpp:
+        (WebKit::WebPage::prepareToSendUserMediaPermissionRequest):
+        * WebProcess/WebPage/WebPage.h:
+        * WebProcess/WebPage/ios/WebPageIOS.mm:
+        (WebKit::WebPage::prepareToSendUserMediaPermissionRequest):
+        * WebProcess/cocoa/WebProcessCocoa.mm:
+        (WebKit::WebProcess::platformInitializeWebProcess):
+
 2017-10-21  Michael Catanzaro  <mcatanzaro@igalia.com>
 
         Unreviewed, silence a -Wunused-but-set-variable warning

Source/WebKit/WebProcess/WebCoreSupport/WebUserMediaClient.cpp

@@ -43,6 +43,7 @@ void WebUserMediaClient::pageDestroyed()
 
 void WebUserMediaClient::requestUserMediaAccess(UserMediaRequest& request)
 {
+    m_page.prepareToSendUserMediaPermissionRequest();
     m_page.userMediaPermissionRequestManager().startUserMediaRequest(request);
 }
 

Source/WebKit/WebProcess/WebPage/WebPage.cpp

@@ -3898,6 +3898,13 @@ void WebPage::didReceiveNotificationPermissionDecision(uint64_t notificationID,
 }
 
 #if ENABLE(MEDIA_STREAM)
+
+#if !PLATFORM(IOS)
+void WebPage::prepareToSendUserMediaPermissionRequest()
+{
+}
+#endif
+
 void WebPage::userMediaAccessWasGranted(uint64_t userMediaID, String&& audioDeviceUID, String&& videoDeviceUID, String&& mediaDeviceIdentifierHashSalt)
 {
     m_userMediaPermissionRequestManager->userMediaAccessWasGranted(userMediaID, WTFMove(audioDeviceUID), WTFMove(videoDeviceUID), WTFMove(mediaDeviceIdentifierHashSalt));

Source/WebKit/WebProcess/WebPage/WebPage.h

@@ -511,6 +511,7 @@ class WebPage : public API::ObjectImpl<API::Object::Type::BundlePage>, public IP
 
 #if ENABLE(MEDIA_STREAM)
     UserMediaPermissionRequestManager& userMediaPermissionRequestManager() { return *m_userMediaPermissionRequestManager; }
+    void prepareToSendUserMediaPermissionRequest();
 #endif
 
     void elementDidFocus(WebCore::Node*);

Source/WebKit/WebProcess/WebPage/ios/WebPageIOS.mm

@@ -99,6 +99,7 @@
 #import <WebCore/RenderImage.h>
 #import <WebCore/RenderThemeIOS.h>
 #import <WebCore/RenderView.h>
+#import <WebCore/RuntimeApplicationChecks.h>
 #import <WebCore/Settings.h>
 #import <WebCore/SharedBuffer.h>
 #import <WebCore/StyleProperties.h>
@@ -110,8 +111,16 @@
 #import <wtf/MathExtras.h>
 #import <wtf/MemoryPressureHandler.h>
 #import <wtf/SetForScope.h>
+#import <wtf/SoftLinking.h>
 #import <wtf/text/TextStream.h>
 
+#if ENABLE(MEDIA_STREAM)
+#import "CelestialSPI.h"
+SOFT_LINK_PRIVATE_FRAMEWORK_OPTIONAL(Celestial)
+SOFT_LINK_CLASS_OPTIONAL(Celestial, AVSystemController)
+SOFT_LINK_CONSTANT_MAY_FAIL(Celestial, AVSystemController_PIDToInheritApplicationStateFrom, NSString *)
+#endif
+
 using namespace WebCore;
 
 namespace WebKit {
@@ -3411,6 +3420,22 @@ static bool selectionIsInsideFixedPositionContainer(Frame& frame)
 }
 #endif
 
+#if ENABLE(MEDIA_STREAM)
+void WebPage::prepareToSendUserMediaPermissionRequest()
+{
+    static std::once_flag once;
+    std::call_once(once, [] {
+        if (!canLoadAVSystemController_PIDToInheritApplicationStateFrom())
+            return;
+
+        NSError *error = nil;
+        [[getAVSystemControllerClass() sharedAVSystemController] setAttribute:@(WebCore::presentingApplicationPID()) forKey:getAVSystemController_PIDToInheritApplicationStateFrom() error:&error];
+        if (error)
+            WTFLogAlways("Failed to set up PID proxying: %s", error.localizedDescription.UTF8String);
+    });
+}
+#endif
+
 } // namespace WebKit
 
 #endif // PLATFORM(IOS)

Source/WebKit/WebProcess/cocoa/WebProcessCocoa.mm

@@ -70,25 +70,13 @@
 #import <stdio.h>
 
 #if PLATFORM(IOS)
-#import "CelestialSPI.h"
 #import <pal/spi/ios/GraphicsServicesSPI.h>
-#import <wtf/SoftLinking.h>
 #endif
 
 #if USE(OS_STATE)
 #import <os/state_private.h>
 #endif
 
-#if PLATFORM(IOS)
-SOFT_LINK_PRIVATE_FRAMEWORK_OPTIONAL(Celestial)
-
-SOFT_LINK_CLASS_OPTIONAL(Celestial, AVSystemController)
-
-SOFT_LINK_CONSTANT_MAY_FAIL(Celestial, AVSystemController_PIDToInheritApplicationStateFrom, NSString *)
-
-#define AVSystemController_PIDToInheritApplicationStateFrom getAVSystemController_PIDToInheritApplicationStateFrom()
-#endif
-
 using namespace WebCore;
 
 namespace WebKit {
@@ -175,16 +163,6 @@ static id NSApplicationAccessibilityFocusedUIElement(NSApplication*, SEL)
     // Priority decay on iOS 9 is impacting page load time so we fix the priority of the WebProcess' main thread (rdar://problem/22003112).
     pthread_set_fixedpriority_self();
 #endif
-
-#if PLATFORM(IOS)
-    if (canLoadAVSystemController_PIDToInheritApplicationStateFrom()) {
-        pid_t pid = WebCore::presentingApplicationPID();
-        NSError *error = nil;
-        [[getAVSystemControllerClass() sharedAVSystemController] setAttribute:@(pid) forKey:AVSystemController_PIDToInheritApplicationStateFrom error:&error];
-        if (error)
-            WTFLogAlways("Failed to set up PID proxying: %s", [[error localizedDescription] UTF8String]);
-    }
-#endif
 }
 
 void WebProcess::initializeProcessName(const ChildProcessInitializationParameters& parameters)