1091970 - [e10s] Package the shim's "object tag" along with all new CPOWs

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

Attachment: cache-obj-tag

Whenever the add-on shims wrap an object, they first compute its "object tag". They really just do a few instanceof checks to see if it's a XUL node, a window, a docshell, or whatever. In particular, when the object is a CPOW, we do two instanceof checks. Each one sends a sync IPC message.

Like in bug 1091964, this information is constant for a given object. So this patch just sends the tag along with the CPOW, same as in bug 1091964. I had to make a new interface for doing this.

This patch reduces the number of CPOW IPCs we do on my testcase from 16837 to 8100.

Comment 1

[Blake Kaplan (:mrbkap) (inactive)]

Comment on attachment 8514716 [details] [diff] [review]
cache-obj-tag

Review of attachment 8514716 [details] [diff] [review]:
-----------------------------------------------------------------

::: js/xpconnect/idl/xpccomponents.idl
@@ +441,5 @@
> +     * nsIRemoteTagService.getRemoteObjectTag method. It's sent along
> +     * with the CPOW to the remote process, where it can be fetched
> +     * with this function, getCrossProcessWrapperTag.
> +     */
> +    ACString getCrossProcessWrapperTag(in jsval obj);

Need to bump the IID.

Comment 2

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/38ca6211d1d4

Comment 3

[Carsten Book [:Tomcat]]

sorry had to back this out in https://treeherder.mozilla.org/ui/#/jobs?repo=mozilla-inbound&revision=541dc2f509e2 since of this changes seems to have caused test failures like https://treeherder.mozilla.org/ui/logviewer.html#?job_id=3605040&repo=mozilla-inbound

Comment 4

[Bill McCloskey [inactive unless it's an emergency] (:billm)]

The rooting hazards that this patch was implicated in did not go away after the backout. Relanding.
https://hg.mozilla.org/integration/mozilla-inbound/rev/c97553c13fb6

Comment 5

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/c97553c13fb6