Bug 159301 - [iOS] WebContent processes do not exit promptly
Summary: [iOS] WebContent processes do not exit promptly
Status: RESOLVED FIXED
Alias: None
Product: WebKit
Classification: Unclassified
Component: WebKit2 (show other bugs)
Version: WebKit Nightly Build
Hardware: Unspecified Unspecified
: P2 Normal
Assignee: Chris Dumez
URL:
Keywords: InRadar
Depends on:
Blocks:
 
Reported: 2016-06-30 09:05 PDT by Chris Dumez
Modified: 2016-08-18 15:28 PDT (History)
9 users (show)

See Also:

Attachments
WIP Patch (6.44 KB, patch)
2016-06-30 09:14 PDT, Chris Dumez 		no flags Details | Formatted Diff | Diff
Patch (8.19 KB, patch)
2016-06-30 14:25 PDT, Chris Dumez 		no flags Details | Formatted Diff | Diff
Patch (17.21 KB, patch)
2016-06-30 15:21 PDT, Chris Dumez 		no flags Details | Formatted Diff | Diff
Patch (17.92 KB, patch)
2016-06-30 15:50 PDT, Chris Dumez 		no flags Details | Formatted Diff | Diff
Patch (17.92 KB, patch)
2016-06-30 16:09 PDT, Chris Dumez 		no flags Details | Formatted Diff | Diff
Archive of layout-test-results from ews106 for mac-yosemite-wk2 (575.59 KB, application/zip)
2016-06-30 16:33 PDT, Build Bot 		no flags Details
Patch (18.00 KB, patch)
2016-06-30 16:38 PDT, Chris Dumez 		no flags Details | Formatted Diff | Diff
Patch (18.00 KB, patch)
2016-06-30 17:51 PDT, Chris Dumez 		no flags Details | Formatted Diff | Diff
Show Obsolete (7) View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description Chris Dumez 2016-06-30 09:05:23 PDT 
WebContent processes do not exit promptly, they hang around for 10 seconds until the watchdog forcefully calls exit().
Comment 1 Chris Dumez 2016-06-30 09:05:42 PDT 
<rdar://problem/26965488>
Comment 2 Chris Dumez 2016-06-30 09:14:24 PDT 
Created attachment 282445 [details]
WIP Patch
Comment 3 Chris Dumez 2016-06-30 09:23:16 PDT 
Comment on attachment 282445 [details]
WIP Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=282445&action=review

> Source/WebKit2/Shared/EntryPointUtilities/mac/XPCService/XPCServiceMain.mm:76
> +                xpc_object_t leakedReplyForBoosting = xpc_dictionary_create_reply(event);

Sadly, this does not appear to work in practice. While it no longer prevents XPC exit, the WebContent process no longer gets boosted either :/
Comment 4 Chris Dumez 2016-06-30 14:25:58 PDT 
Created attachment 282465 [details]
Patch
Comment 5 Chris Dumez 2016-06-30 15:21:14 PDT 
Created attachment 282474 [details]
Patch
Comment 6 Chris Dumez 2016-06-30 15:22:18 PDT 
Updated based on offline review feedback from Anders. It fixes the issue and is a bit nicer now.
Comment 7 Chris Dumez 2016-06-30 15:50:30 PDT 
Created attachment 282482 [details]
Patch
Comment 8 Chris Dumez 2016-06-30 16:09:59 PDT 
Created attachment 282488 [details]
Patch
Comment 9 Build Bot 2016-06-30 16:33:39 PDT 
Comment on attachment 282488 [details]
Patch

Attachment 282488 [details] did not pass mac-wk2-ews (mac-wk2):
Output: http://webkit-queues.webkit.org/results/1603188

Number of test failures exceeded the failure limit.
Comment 10 Build Bot 2016-06-30 16:33:44 PDT 
Created attachment 282490 [details]
Archive of layout-test-results from ews106 for mac-yosemite-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: ews106  Port: mac-yosemite-wk2  Platform: Mac OS X 10.10.5
Comment 11 Chris Dumez 2016-06-30 16:38:17 PDT 
Created attachment 282491 [details]
Patch
Comment 12 Chris Dumez 2016-06-30 16:44:49 PDT 
Comment on attachment 282491 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=282491&action=review

> Source/WebKit2/Shared/EntryPointUtilities/mac/XPCService/XPCServiceEntryPoint.h:84
> +    parameters.priorityBoostMessage = priorityBoostMessage ? adoptOSObject(xpc_retain(priorityBoostMessage)) : nullptr;

The crashes on the Mac bots were because we only use priority boosting for the NetworkProcess on Mac. Therefore, for other processes would have a null priorityBoostMessage and calling xpc_retain() on nullptr crashes. I added a null check here.

> Source/WebKit2/Shared/EntryPointUtilities/mac/XPCService/XPCServiceMain.mm:74
> +                if (priorityBoostMessage)

Also added a null check to avoid calling xlc_release() on null.
Comment 13 Chris Dumez 2016-06-30 17:51:08 PDT 
Created attachment 282495 [details]
Patch
Comment 14 Chris Dumez 2016-06-30 18:30:13 PDT 
Comment on attachment 282495 [details]
Patch

Clearing flags on attachment: 282495

Committed r202723: <http://trac.webkit.org/changeset/202723>
Comment 15 Chris Dumez 2016-06-30 18:30:19 PDT 
All reviewed patches have been landed.  Closing bug.