791640 - Event tracer freezes Fennec

Status: RESOLVED FIXED

(Core :: Gecko Profiler, defect)

Description

[Mike Hommey [:glandium]]

This was first spotted when enabling the SPS profiler on Fennec: Fennec would freeze when trying to use the awesomebar. It turns out this is reproducible without enabling the SPS profiler at all, but by enabling the Event tracer alone.

STR:
- Start fennec with: am start -a android.activity.MAIN -n org.mozilla.fennec/.App --es env0 MOZ_INSTRUMENT_EVENT_LOOP=1
- Tap the url bar
- If it doesn't freeze straight away, try switching between Top sites/Bookmarks/History
- If it still doesn't freeze, try opening a web site and repeat the steps from "Tap the url bar".

On my nexus S, it happens sometimes the first time the url bar is tapped, if it doesn't happen then, it happens all the time after having opened an web site.

Comment 1

[Benoit Girard (:BenWa)]

Here's the state of the main dalvik thread when deadlock:

"main" prio=5 tid=1 WAIT
  | group="main" sCount=1 dsCount=0 obj=0x40a47460 self=0xbc8828
  | sysTid=13769 nice=0 sched=0/0 cgrp=default handle=1074308232
  | schedstat=( 0 0 0 ) utm=302 stm=87 core=1
  at java.lang.Object.wait(Native Method)
  - waiting on <0x40a47530> (a java.lang.VMThread) held by tid=1 (main)
  at java.lang.Thread.parkFor(Thread.java:1231)
  at sun.misc.Unsafe.park(Unsafe.java:323)
  at java.util.concurrent.locks.LockSupport.park(LockSupport.java:157)
  at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:813)
  at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:973)
  at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1282)
  at java.util.concurrent.CountDownLatch.await(CountDownLatch.java:207)
  at org.mozilla.gecko.GeckoAppShell.geckoEventSync(GeckoAppShell.java:610)
  at org.mozilla.gecko.GeckoAppShell.sendEventToGeckoSync(GeckoAppShell.java:567)
  at org.mozilla.gecko.gfx.GeckoLayerClient.compositionPauseRequested(GeckoLayerClient.java:567)
  at org.mozilla.gecko.gfx.LayerView.onDestroyed(LayerView.java:320)
  at org.mozilla.gecko.gfx.LayerView.access$300(LayerView.java:44)
  at org.mozilla.gecko.gfx.LayerView$SurfaceListener.surfaceDestroyed(LayerView.java:361)
  at android.view.SurfaceView.updateWindow(SurfaceView.java:517)
  at android.view.SurfaceView.onWindowVisibilityChanged(SurfaceView.java:226)
  at android.view.View.dispatchWindowVisibilityChanged(View.java:5839)
  at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:945)
  at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:945)
  at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:945)
  at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:945)
  at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:945)
  at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:945)
  at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:945)
  at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:965)
  at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2442)
  at android.os.Handler.dispatchMessage(Handler.java:99)
  at android.os.Looper.loop(Looper.java:137)
  at android.app.ActivityThread.main(ActivityThread.java:4424)
  at java.lang.reflect.Method.invokeNative(Native Method)
  at java.lang.reflect.Method.invoke(Method.java:511)
  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
  at dalvik.system.NativeStart.main(Native Method)

Comment 3

[Benoit Girard (:BenWa)]

Attachment: EventTracer will only measure the main thread responsiveness

Comment 4

[Benoit Girard (:BenWa)]

http://hg.mozilla.org/integration/mozilla-inbound/rev/7adfb6640886

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/7adfb6640886