1794376 - CacheFileIOManager's ShutdownEvent should use SpinEventLoopUntil

Status: RESOLVED FIXED

(Core :: Networking: Cache, task, P2)

Description

[Jens Stutte [:jstutte]]

Currently we have in PostAndWait the following blocking loop:

    TimeDuration waitTime = TimeDuration::FromSeconds(1);
    while (!mNotified) {
      mon.Wait(waitTime);
      if (!mNotified) {
        // If there is any IO blocking on the IO thread, this will
        // try to cancel it.  Returns no later than after two seconds.
        MonitorAutoUnlock unmon(mMonitor);  // Prevent delays
        CacheFileIOManager::gInstance->mIOThread->CancelBlockingIO();
      }
    }

which is (potentially) executed on the main thread and might lead to a hang.

We probably want to use a SpinEventLoopUntil here and maybe revisit also BlockingIOWatcher::WatchAndCancel.

Comment 1

[Valentin Gosu [:valentin] (he/him)]

Attachment: Bug 1794376 - Use SpinEventLoopUntil to await for CacheFileIOManager shutdown r=jstutte

Comment 2

[Valentin Gosu [:valentin] (he/him)]

Attachment: Bug 1794376 - Rename BlockingIOWatcher and simplify code r=#necko

Depends on D159845

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b92724a7bcb6
Use SpinEventLoopUntil to await for CacheFileIOManager shutdown r=jstutte,edgul
https://hg.mozilla.org/integration/autoland/rev/43b8474c2eae
Rename BlockingIOWatcher and simplify code r=edgul

Comment 4

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/b92724a7bcb6
https://hg.mozilla.org/mozilla-central/rev/43b8474c2eae