- Revision
- 266645
- Author
- [email protected]
- Date
- 2020-09-04 16:30:30 -0700 (Fri, 04 Sep 2020)
Log Message
Move lazy DisplayLink tear down logic from the WebProcess to the UIProcess
https://bugs.webkit.org/show_bug.cgi?id=216195
Reviewed by Simon Fraser.
Move lazy DisplayLink tear down logic from the WebProcess to the UIProcess, now that the
DisplayLink has been moved to the UIProcess due to sandboxing.
After a DisplayLink no longer has any clients, we keep it firing up to 20 times without
any clients in case a new client gets added shortly after. The idea was to avoid killing
and respawning too many threads when adding and removing clients in quick succession.
However, now that the DisplayLink lives in the UIProcess side and sends IPC to the
WebProcesses every time it fires, it makes a lot more sense to implement this logic in
the UIProcess side, to avoid sending unnecessary IPC to processes that do not care about
it.
Source/WebCore:
* platform/graphics/DisplayRefreshMonitor.cpp:
(WebCore::DisplayRefreshMonitor::displayDidRefresh):
* platform/graphics/DisplayRefreshMonitor.h:
(WebCore::DisplayRefreshMonitor::shouldBeTerminated const):
Source/WebKit:
* UIProcess/mac/DisplayLink.cpp:
(WebKit::DisplayLink::addObserver):
(WebKit::DisplayLink::removeObserver):
(WebKit::DisplayLink::removeObservers):
(WebKit::DisplayLink::displayLinkCallback):
(WebKit::DisplayLink::hasObservers const): Deleted.
* UIProcess/mac/DisplayLink.h:
Modified Paths
Diff
Modified: trunk/Source/WebCore/ChangeLog (266644 => 266645)
--- trunk/Source/WebCore/ChangeLog 2020-09-04 23:19:12 UTC (rev 266644)
+++ trunk/Source/WebCore/ChangeLog 2020-09-04 23:30:30 UTC (rev 266645)
@@ -1,3 +1,26 @@
+2020-09-04 Chris Dumez <[email protected]>
+
+ Move lazy DisplayLink tear down logic from the WebProcess to the UIProcess
+ https://bugs.webkit.org/show_bug.cgi?id=216195
+
+ Reviewed by Simon Fraser.
+
+ Move lazy DisplayLink tear down logic from the WebProcess to the UIProcess, now that the
+ DisplayLink has been moved to the UIProcess due to sandboxing.
+
+ After a DisplayLink no longer has any clients, we keep it firing up to 20 times without
+ any clients in case a new client gets added shortly after. The idea was to avoid killing
+ and respawning too many threads when adding and removing clients in quick succession.
+ However, now that the DisplayLink lives in the UIProcess side and sends IPC to the
+ WebProcesses every time it fires, it makes a lot more sense to implement this logic in
+ the UIProcess side, to avoid sending unnecessary IPC to processes that do not care about
+ it.
+
+ * platform/graphics/DisplayRefreshMonitor.cpp:
+ (WebCore::DisplayRefreshMonitor::displayDidRefresh):
+ * platform/graphics/DisplayRefreshMonitor.h:
+ (WebCore::DisplayRefreshMonitor::shouldBeTerminated const):
+
2020-09-04 Jer Noble <[email protected]>
[Cocoa,EME] -outputObscuredDueToInsufficientExternalProtection KVO will set OutputObscured for all attached MediaKeySessions.
Modified: trunk/Source/WebCore/platform/graphics/DisplayRefreshMonitor.cpp (266644 => 266645)
--- trunk/Source/WebCore/platform/graphics/DisplayRefreshMonitor.cpp 2020-09-04 23:19:12 UTC (rev 266644)
+++ trunk/Source/WebCore/platform/graphics/DisplayRefreshMonitor.cpp 2020-09-04 23:30:30 UTC (rev 266645)
@@ -94,12 +94,7 @@
{
{
LockHolder lock(m_mutex);
- LOG(RequestAnimationFrame, "DisplayRefreshMonitor::displayDidRefresh(%p) - m_scheduled(%d), m_unscheduledFireCount(%d)", this, m_scheduled, m_unscheduledFireCount);
- if (!m_scheduled)
- ++m_unscheduledFireCount;
- else
- m_unscheduledFireCount = 0;
-
+ LOG(RequestAnimationFrame, "DisplayRefreshMonitor::displayDidRefresh(%p) - m_scheduled(%d)", this, m_scheduled);
m_scheduled = false;
}
Modified: trunk/Source/WebCore/platform/graphics/DisplayRefreshMonitor.h (266644 => 266645)
--- trunk/Source/WebCore/platform/graphics/DisplayRefreshMonitor.h 2020-09-04 23:19:12 UTC (rev 266644)
+++ trunk/Source/WebCore/platform/graphics/DisplayRefreshMonitor.h 2020-09-04 23:30:30 UTC (rev 266645)
@@ -60,11 +60,7 @@
PlatformDisplayID displayID() const { return m_displayID; }
- bool shouldBeTerminated() const
- {
- const int maxInactiveFireCount = 20;
- return !m_scheduled && m_unscheduledFireCount > maxInactiveFireCount;
- }
+ bool shouldBeTerminated() const { return !m_scheduled; }
static RefPtr<DisplayRefreshMonitor> createDefaultDisplayRefreshMonitor(PlatformDisplayID);
@@ -94,7 +90,6 @@
HashSet<DisplayRefreshMonitorClient*>* m_clientsToBeNotified { nullptr };
Lock m_mutex;
PlatformDisplayID m_displayID { 0 };
- int m_unscheduledFireCount { 0 }; // Number of times the display link has fired with no clients.
bool m_active { true };
bool m_scheduled { false };
bool m_previousFrameDone { true };
Modified: trunk/Source/WebKit/ChangeLog (266644 => 266645)
--- trunk/Source/WebKit/ChangeLog 2020-09-04 23:19:12 UTC (rev 266644)
+++ trunk/Source/WebKit/ChangeLog 2020-09-04 23:30:30 UTC (rev 266645)
@@ -1,3 +1,29 @@
+2020-09-04 Chris Dumez <[email protected]>
+
+ Move lazy DisplayLink tear down logic from the WebProcess to the UIProcess
+ https://bugs.webkit.org/show_bug.cgi?id=216195
+
+ Reviewed by Simon Fraser.
+
+ Move lazy DisplayLink tear down logic from the WebProcess to the UIProcess, now that the
+ DisplayLink has been moved to the UIProcess due to sandboxing.
+
+ After a DisplayLink no longer has any clients, we keep it firing up to 20 times without
+ any clients in case a new client gets added shortly after. The idea was to avoid killing
+ and respawning too many threads when adding and removing clients in quick succession.
+ However, now that the DisplayLink lives in the UIProcess side and sends IPC to the
+ WebProcesses every time it fires, it makes a lot more sense to implement this logic in
+ the UIProcess side, to avoid sending unnecessary IPC to processes that do not care about
+ it.
+
+ * UIProcess/mac/DisplayLink.cpp:
+ (WebKit::DisplayLink::addObserver):
+ (WebKit::DisplayLink::removeObserver):
+ (WebKit::DisplayLink::removeObservers):
+ (WebKit::DisplayLink::displayLinkCallback):
+ (WebKit::DisplayLink::hasObservers const): Deleted.
+ * UIProcess/mac/DisplayLink.h:
+
2020-09-04 Sihui Liu <[email protected]>
Webpages flash when switching between windows
Modified: trunk/Source/WebKit/UIProcess/mac/DisplayLink.cpp (266644 => 266645)
--- trunk/Source/WebKit/UIProcess/mac/DisplayLink.cpp 2020-09-04 23:19:12 UTC (rev 266644)
+++ trunk/Source/WebKit/UIProcess/mac/DisplayLink.cpp 2020-09-04 23:30:30 UTC (rev 266645)
@@ -32,6 +32,8 @@
#include <wtf/ProcessPrivilege.h>
namespace WebKit {
+
+constexpr unsigned maxFireCountWithObservers { 20 };
DisplayLink::DisplayLink(WebCore::PlatformDisplayID displayID)
: m_displayID(displayID)
@@ -72,16 +74,13 @@
void DisplayLink::addObserver(IPC::Connection& connection, DisplayLinkObserverID observerID)
{
ASSERT(RunLoop::isMain());
- bool isRunning = !m_observers.isEmpty();
- {
- LockHolder locker(m_observersLock);
- m_observers.ensure(&connection, [] {
- return Vector<DisplayLinkObserverID> { };
- }).iterator->value.append(observerID);
- }
+ LockHolder locker(m_observersLock);
+ m_observers.ensure(&connection, [] {
+ return Vector<DisplayLinkObserverID> { };
+ }).iterator->value.append(observerID);
- if (!isRunning) {
+ if (!CVDisplayLinkIsRunning(m_displayLink)) {
CVReturn error = CVDisplayLinkStart(m_displayLink);
if (error)
WTFLogAlways("Could not start the display link: %d", error);
@@ -92,20 +91,19 @@
{
ASSERT(RunLoop::isMain());
- {
- LockHolder locker(m_observersLock);
+ LockHolder locker(m_observersLock);
- auto it = m_observers.find(&connection);
- if (it == m_observers.end())
- return;
- bool removed = it->value.removeFirst(observerID);
- ASSERT_UNUSED(removed, removed);
- if (it->value.isEmpty())
- m_observers.remove(it);
- }
+ auto it = m_observers.find(&connection);
+ if (it == m_observers.end())
+ return;
+ bool removed = it->value.removeFirst(observerID);
+ ASSERT_UNUSED(removed, removed);
+ if (it->value.isEmpty())
+ m_observers.remove(it);
- if (m_observers.isEmpty())
- CVDisplayLinkStop(m_displayLink);
+ // We do not stop the display link right away when |m_observers| becomes empty. Instead, we
+ // let the display link fire up to |maxFireCountWithObservers| times without observers to avoid
+ // killing & restarting too many threads when observers gets removed & added in quick succession.
}
void DisplayLink::removeObservers(IPC::Connection& connection)
@@ -112,25 +110,27 @@
{
ASSERT(RunLoop::isMain());
- {
- LockHolder locker(m_observersLock);
- m_observers.remove(&connection);
- }
+ LockHolder locker(m_observersLock);
+ m_observers.remove(&connection);
- if (m_observers.isEmpty())
- CVDisplayLinkStop(m_displayLink);
+ // We do not stop the display link right away when |m_observers| becomes empty. Instead, we
+ // let the display link fire up to |maxFireCountWithObservers| times without observers to avoid
+ // killing & restarting too many threads when observers gets removed & added in quick succession.
}
-bool DisplayLink::hasObservers() const
-{
- ASSERT(RunLoop::isMain());
- return !m_observers.isEmpty();
-}
-
CVReturn DisplayLink::displayLinkCallback(CVDisplayLinkRef displayLinkRef, const CVTimeStamp*, const CVTimeStamp*, CVOptionFlags, CVOptionFlags*, void* data)
{
+ ASSERT(!RunLoop::isMain());
auto* displayLink = static_cast<DisplayLink*>(data);
+
LockHolder locker(displayLink->m_observersLock);
+ if (displayLink->m_observers.isEmpty()) {
+ if (++(displayLink->m_fireCountWithoutObservers) >= maxFireCountWithObservers)
+ CVDisplayLinkStop(displayLink->m_displayLink);
+ return kCVReturnSuccess;
+ }
+ displayLink->m_fireCountWithoutObservers = 0;
+
for (auto& connection : displayLink->m_observers.keys())
connection->send(Messages::EventDispatcher::DisplayWasRefreshed(displayLink->m_displayID), 0);
return kCVReturnSuccess;
Modified: trunk/Source/WebKit/UIProcess/mac/DisplayLink.h (266644 => 266645)
--- trunk/Source/WebKit/UIProcess/mac/DisplayLink.h 2020-09-04 23:19:12 UTC (rev 266644)
+++ trunk/Source/WebKit/UIProcess/mac/DisplayLink.h 2020-09-04 23:30:30 UTC (rev 266645)
@@ -48,7 +48,6 @@
void addObserver(IPC::Connection&, DisplayLinkObserverID);
void removeObserver(IPC::Connection&, DisplayLinkObserverID);
void removeObservers(IPC::Connection&);
- bool hasObservers() const;
WebCore::PlatformDisplayID displayID() const { return m_displayID; }
@@ -61,6 +60,7 @@
Lock m_observersLock;
HashMap<RefPtr<IPC::Connection>, Vector<DisplayLinkObserverID>> m_observers;
WebCore::PlatformDisplayID m_displayID;
+ unsigned m_fireCountWithoutObservers { 0 };
};
} // namespace WebKit
