commit 19c2ee2e7a37bbeca96392734fbefddb4f0ab2fa
author simon.fraser@apple.com <simon.fraser@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> Wed Oct 16 01:04:41 2019 +0000
committer simon.fraser@apple.com <simon.fraser@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> Wed Oct 16 01:04:41 2019 +0000
tree 77a1394e19fc593a130567ba38620e3a8a4b1dfd
parent a0579d6ac3a4a1112ab2cf96dfcf46250b108a1a

WheelEventTestMonitor doesn't need to be threadsafe
https://bugs.webkit.org/show_bug.cgi?id=203012

Reviewed by Dean Jackson.

WheelEventTestMonitor is only called on the main thread, so doesn't need a lock to protect
m_deferCompletionReasons, and add main thread assertions.

* page/WheelEventTestMonitor.cpp:
(WebCore::WheelEventTestMonitor::clearAllTestDeferrals):
(WebCore::WheelEventTestMonitor::setTestCallbackAndStartNotificationTimer):
(WebCore::WheelEventTestMonitor::deferForReason):
(WebCore::WheelEventTestMonitor::removeDeferralForReason):
(WebCore::WheelEventTestMonitor::triggerTestTimerFired):
* page/WheelEventTestMonitor.h:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@251172 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebCore/ChangeLog

diff --git a/Source/WebCore/ChangeLog b/Source/WebCore/ChangeLog
index 6c382f5..36e44ec 100644
--- a/Source/WebCore/ChangeLog
+++ b/Source/WebCore/ChangeLog
@@ -1,3 +1,21 @@
+2019-10-15  Simon Fraser  <simon.fraser@apple.com>
+
+        WheelEventTestMonitor doesn't need to be threadsafe
+        https://bugs.webkit.org/show_bug.cgi?id=203012
+
+        Reviewed by Dean Jackson.
+
+        WheelEventTestMonitor is only called on the main thread, so doesn't need a lock to protect
+        m_deferCompletionReasons, and add main thread assertions.
+
+        * page/WheelEventTestMonitor.cpp:
+        (WebCore::WheelEventTestMonitor::clearAllTestDeferrals):
+        (WebCore::WheelEventTestMonitor::setTestCallbackAndStartNotificationTimer):
+        (WebCore::WheelEventTestMonitor::deferForReason):
+        (WebCore::WheelEventTestMonitor::removeDeferralForReason):
+        (WebCore::WheelEventTestMonitor::triggerTestTimerFired):
+        * page/WheelEventTestMonitor.h:
+
 2019-10-15  Andres Gonzalez  <andresg_22@apple.com>
 
         AX: Make AXIsolatedTree compile again

Source/WebCore/page/WheelEventTestMonitor.cpp

diff --git a/Source/WebCore/page/WheelEventTestMonitor.cpp b/Source/WebCore/page/WheelEventTestMonitor.cpp
index 061ff11..1b68303 100644
--- a/Source/WebCore/page/WheelEventTestMonitor.cpp
+++ b/Source/WebCore/page/WheelEventTestMonitor.cpp
@@ -46,7 +46,7 @@
 
 void WheelEventTestMonitor::clearAllTestDeferrals()
 {
-    std::lock_guard<Lock> lock(m_reasonsLock);
+    ASSERT(isMainThread());
     m_deferCompletionReasons.clear();
     m_completionCallback = nullptr;
     m_testForCompletionTimer.stop();
@@ -55,10 +55,8 @@
 
 void WheelEventTestMonitor::setTestCallbackAndStartNotificationTimer(WTF::Function<void()>&& functionCallback)
 {
-    {
-        std::lock_guard<Lock> lock(m_reasonsLock);
-        m_completionCallback = WTFMove(functionCallback);
-    }
+    ASSERT(isMainThread());
+    m_completionCallback = WTFMove(functionCallback);
     
     if (!m_testForCompletionTimer.isActive())
         m_testForCompletionTimer.startRepeating(1_s / 60.);
@@ -66,7 +64,7 @@
 
 void WheelEventTestMonitor::deferForReason(ScrollableAreaIdentifier identifier, DeferReason reason)
 {
-    std::lock_guard<Lock> lock(m_reasonsLock);
+    ASSERT(isMainThread());
     m_deferCompletionReasons.ensure(identifier, [] {
         return OptionSet<DeferReason>();
     }).iterator->value.add(reason);
@@ -76,7 +74,7 @@
 
 void WheelEventTestMonitor::removeDeferralForReason(ScrollableAreaIdentifier identifier, DeferReason reason)
 {
-    std::lock_guard<Lock> lock(m_reasonsLock);
+    ASSERT(isMainThread());
     auto it = m_deferCompletionReasons.find(identifier);
     if (it == m_deferCompletionReasons.end())
         return;
@@ -90,18 +88,13 @@
     
 void WheelEventTestMonitor::triggerTestTimerFired()
 {
-    WTF::Function<void()> functionCallback;
-
-    {
-        std::lock_guard<Lock> lock(m_reasonsLock);
-        if (!m_deferCompletionReasons.isEmpty()) {
-            LOG_WITH_STREAM(WheelEventTestMonitor, stream << "  WheelEventTestMonitor::triggerTestTimerFired - scrolling still active, reasons " << m_deferCompletionReasons);
-            return;
-        }
-
-        functionCallback = WTFMove(m_completionCallback);
+    ASSERT(isMainThread());
+    if (!m_deferCompletionReasons.isEmpty()) {
+        LOG_WITH_STREAM(WheelEventTestMonitor, stream << "  WheelEventTestMonitor::triggerTestTimerFired - scrolling still active, reasons " << m_deferCompletionReasons);
+        return;
     }
 
+    auto functionCallback = WTFMove(m_completionCallback);
     m_testForCompletionTimer.stop();
 
     LOG_WITH_STREAM(WheelEventTestMonitor, stream << "  WheelEventTestMonitor::triggerTestTimerFired: scrolling is idle, FIRING TEST");

Source/WebCore/page/WheelEventTestMonitor.h

diff --git a/Source/WebCore/page/WheelEventTestMonitor.h b/Source/WebCore/page/WheelEventTestMonitor.h
index 0cdce5c..b0793a3 100644
--- a/Source/WebCore/page/WheelEventTestMonitor.h
+++ b/Source/WebCore/page/WheelEventTestMonitor.h
@@ -65,7 +65,6 @@
     WTF::Function<void()> m_completionCallback;
     RunLoop::Timer<WheelEventTestMonitor> m_testForCompletionTimer;
 
-    mutable Lock m_reasonsLock;
     ScrollableAreaReasonMap m_deferCompletionReasons;
 };