777514 - B2G Updates: EventHub input loop stops the b2g process from exiting

Status: RESOLVED FIXED

(Core Graveyard :: Widget: Gonk, defect)

Description

[Marshall Culpepper [:marshall_law]]

Currently, process exit will block when ~nsAppShell calls mReaderThread->requestExitAndWait(). This requires the user to do some form of input (touch or button press of some kind) to tick the EventHub loop, and finalize the b2g process teardown.

Comment 1

[Marshall Culpepper [:marshall_law]]

Attachment: event hub wake fix - v1

Comment 2

[Michael Wu [:mwu]]

Hm, can we request an exit, wake, and then wait for exit? I'm a bit afraid that we might wake up, and then go straight back to waiting before we call the exit and wait function.

Comment 3

[Marshall Culpepper [:marshall_law]]

(In reply to Michael Wu [:mwu] from comment #2)
> Hm, can we request an exit, wake, and then wait for exit? I'm a bit afraid
> that we might wake up, and then go straight back to waiting before we call
> the exit and wait function.

Good catch! It looks like we can actually separate out the calls to requestExit() and join() (for waiting), so I'll add the call to mEventHub->wake() between the two, to avoid the second request.

Comment 4

[Marshall Culpepper [:marshall_law]]

Attachment: event hub wake fix - v2

Call requestExit() before waking the EventHub, and then join() (wait)

Comment 5

[Marshall Culpepper [:marshall_law]]

http://hg.mozilla.org/integration/mozilla-inbound/rev/d567f2581365

Comment 6

[Matt Brubeck (:mbrubeck)]

Sorry, I backed this out on inbound:
https://hg.mozilla.org/integration/mozilla-inbound/rev/7ac08cd7d0a3

because of B2G build failures:
https://tbpl.mozilla.org/php/getParsedLog.php?id=13879519&tree=Mozilla-Inbound
../../../widget/gonk/nsAppShell.cpp:501: error: 'class android::InputReaderThread' has no member named 'join'

Comment 7

[Marshall Culpepper [:marshall_law]]

Ugh, this looks like another Tinderbox GB toolchain issue. See Bug 776045

Comment 8

[Marshall Culpepper [:marshall_law]]

In integration w/ GB safe APIs:

https://hg.mozilla.org/integration/mozilla-inbound/rev/0f7d2d447ed5

Comment 9

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/0f7d2d447ed5