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geoffreygarengeoffreygaren
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Use a Version 1 CFRunLoopSource for faster task dispatch
https://bugs.webkit.org/show_bug.cgi?id=202874 Reviewed by Simon Fraser. Source/WTF: This performance bottleneck showed up in IndexedDB. We worked around it by switching to WorkQueueMessageReceiver. Now it's showing up again in the GPU Process. * wtf/RunLoop.h: Added a mach port. We use this for wake-up. * wtf/cf/RunLoopCF.cpp: (WTF::RunLoop::performWork): Use the standard declaration for a Version 1 run loop source callback. (WTF::RunLoop::RunLoop): Use a dummy mach port for wake-ups. The default wake-up mechanism uses pthread APIs, which cost hundreds of microseconds per invocation, even on the most modern hardware. In contrast, a mach message takes about nine microseconds. (WTF::RunLoop::~RunLoop): Free the mach port. (WTF::RunLoop::wakeUp): Copy-pasted code to signal a mach port. The message payload doesn't matter because we're just trying to achieve a wakeup, kind of like calling a void() function. Tools: Fixed a test incompatibiilty. * TestWebKitAPI/cocoa/UtilitiesCocoa.mm: (TestWebKitAPI::Util::spinRunLoop): Be sure to run the runloop until it runs out of sources to handle. The SuspendServiceWorkerProcessBasedOnClientProcesses test invokes spinRunLoop while adding items to the runloop. Under those conditions, whether a given source will fire or not in a single invocation of CFRunLoopRunInMode is undefined behavior. Canonical link: https://commits.webkit.org/231841@main git-svn-id: https://svn.webkit.org/repository/webkit/trunk@270132 268f45cc-cd09-0410-ab3c-d52691b4dbfc
1 parent 5913ebf commit a3e58f1

5 files changed

Lines changed: 66 additions & 8 deletions

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‎Source/WTF/ChangeLog‎

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@@ -1,3 +1,31 @@
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2020-11-20 Geoffrey Garen <ggaren@apple.com>
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Use a Version 1 CFRunLoopSource for faster task dispatch
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https://bugs.webkit.org/show_bug.cgi?id=202874
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Reviewed by Simon Fraser.
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This performance bottleneck showed up in IndexedDB. We worked around it
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by switching to WorkQueueMessageReceiver. Now it's showing up again
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in the GPU Process.
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* wtf/RunLoop.h: Added a mach port. We use this for wake-up.
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* wtf/cf/RunLoopCF.cpp:
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(WTF::RunLoop::performWork): Use the standard declaration for a
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Version 1 run loop source callback.
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(WTF::RunLoop::RunLoop): Use a dummy mach port for wake-ups. The default
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wake-up mechanism uses pthread APIs, which cost hundreds of microseconds
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per invocation, even on the most modern hardware. In contrast, a mach
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message takes about nine microseconds.
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(WTF::RunLoop::~RunLoop): Free the mach port.
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(WTF::RunLoop::wakeUp): Copy-pasted code to signal a mach port. The
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message payload doesn't matter because we're just trying to achieve
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a wakeup, kind of like calling a void() function.
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2020-11-20 Don Olmstead <don.olmstead@sony.com>
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Remove quota module

‎Source/WTF/wtf/RunLoop.h‎

Lines changed: 2 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -225,9 +225,10 @@ class RunLoop final : public FunctionDispatcher {
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Lock m_loopLock;
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#elif USE(COCOA_EVENT_LOOP)
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static void performWork(void*);
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static void performWork(CFMachPortRef, void* msg, CFIndex size, void* info);
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RetainPtr<CFRunLoopRef> m_runLoop;
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RetainPtr<CFRunLoopSourceRef> m_runLoopSource;
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RetainPtr<CFMachPortRef> m_port;
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#elif USE(GLIB_EVENT_LOOP)
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void notify(Event, const char*);
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‎Source/WTF/wtf/cf/RunLoopCF.cpp‎

Lines changed: 17 additions & 6 deletions
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@@ -28,6 +28,7 @@
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#include <CoreFoundation/CoreFoundation.h>
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#include <dispatch/dispatch.h>
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#include <mach/mach.h>
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#include <wtf/AutodrainedPool.h>
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#include <wtf/SchedulePair.h>
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@@ -40,29 +41,39 @@ static RetainPtr<CFRunLoopTimerRef> createTimer(Seconds interval, bool repeat, v
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return adoptCF(CFRunLoopTimerCreate(kCFAllocatorDefault, CFAbsoluteTimeGetCurrent() + interval.seconds(), repeatInterval.seconds(), 0, 0, timerFired, &context));
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}
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void RunLoop::performWork(void* context)
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void RunLoop::performWork(CFMachPortRef, void*, CFIndex, void* info)
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{
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AutodrainedPool pool;
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static_cast<RunLoop*>(context)->performWork();
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static_cast<RunLoop*>(info)->performWork();
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}
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RunLoop::RunLoop()
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: m_runLoop(CFRunLoopGetCurrent())
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{
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CFRunLoopSourceContext context = { 0, this, 0, 0, 0, 0, 0, 0, 0, performWork };
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m_runLoopSource = adoptCF(CFRunLoopSourceCreate(kCFAllocatorDefault, 0, &context));
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CFMachPortContext context = { 0, this, nullptr, nullptr, nullptr };
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m_port = adoptCF(CFMachPortCreate(kCFAllocatorDefault, performWork, &context, nullptr));
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m_runLoopSource = adoptCF(CFMachPortCreateRunLoopSource(kCFAllocatorDefault, m_port.get(), 0));
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CFRunLoopAddSource(m_runLoop.get(), m_runLoopSource.get(), kCFRunLoopCommonModes);
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}
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RunLoop::~RunLoop()
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{
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CFMachPortInvalidate(m_port.get());
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CFRunLoopSourceInvalidate(m_runLoopSource.get());
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}
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void RunLoop::wakeUp()
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{
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CFRunLoopSourceSignal(m_runLoopSource.get());
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CFRunLoopWakeUp(m_runLoop.get());
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mach_msg_header_t header;
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header.msgh_bits = MACH_MSGH_BITS(MACH_MSG_TYPE_COPY_SEND, 0);
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header.msgh_size = sizeof(mach_msg_header_t);
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header.msgh_remote_port = CFMachPortGetPort(m_port.get());
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header.msgh_local_port = MACH_PORT_NULL;
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header.msgh_id = 0;
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mach_msg_return_t result = mach_msg(&header, MACH_SEND_MSG | MACH_SEND_TIMEOUT, header.msgh_size, 0, MACH_PORT_NULL, 0, MACH_PORT_NULL);
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RELEASE_ASSERT(result == MACH_MSG_SUCCESS || result == MACH_SEND_TIMED_OUT);
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if (result == MACH_SEND_TIMED_OUT)
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mach_msg_destroy(&header);
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}
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RunLoop::CycleResult RunLoop::cycle(RunLoopMode mode)

‎Tools/ChangeLog‎

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@@ -1,3 +1,21 @@
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2020-11-20 Geoffrey Garen <ggaren@apple.com>
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Use a Version 1 CFRunLoopSource for faster task dispatch
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https://bugs.webkit.org/show_bug.cgi?id=202874
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Reviewed by Simon Fraser.
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Fixed a test incompatibiilty.
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* TestWebKitAPI/cocoa/UtilitiesCocoa.mm:
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(TestWebKitAPI::Util::spinRunLoop): Be sure to run the runloop until
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it runs out of sources to handle.
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The SuspendServiceWorkerProcessBasedOnClientProcesses test invokes
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spinRunLoop while adding items to the runloop. Under those conditions,
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whether a given source will fire or not in a single invocation of
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CFRunLoopRunInMode is undefined behavior.
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2020-11-20 Don Olmstead <don.olmstead@sony.com>
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Remove quota module

‎Tools/TestWebKitAPI/cocoa/UtilitiesCocoa.mm‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -38,7 +38,7 @@ void run(bool* done)
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void spinRunLoop(uint64_t count)
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{
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for (uint64_t i = 0; i < count; ++i)
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[[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode beforeDate:[NSDate distantPast]];
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while (CFRunLoopRunInMode(kCFRunLoopDefaultMode, 0, true) == kCFRunLoopRunHandledSource) { }
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}
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void sleep(double seconds)

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