1394494 - Use a custom Frame::Kind for special BHR frame types

Status: RESOLVED FIXED

(Core :: XPCOM, enhancement)

Description

[Nika Layzell [:nika] (ni? for response)]

See bug 1393915 comment 2

Comment 1

[Nika Layzell [:nika] (ni? for response)]

Attachment: Use a custom Frame::Kind for special BHR frame types

I think this should address your comments and make the behavior for deduplicating stack frames more consistent.

Comment 2

[Nathan Froyd [:froydnj]]

Comment on attachment 8901893 [details] [diff] [review]
Use a custom Frame::Kind for special BHR frame types

Review of attachment 8901893 [details] [diff] [review]:
-----------------------------------------------------------------

r=me.  WDYT about the below?

::: toolkit/components/backgroundhangmonitor/HangStack.h
@@ +88,5 @@
>        , mPC(aPC)
>      {}
>  
> +    explicit Frame(Kind aKind)
> +      : mKind(aKind)

I realize it's a bit different from the other kinds, but maybe:

static Frame Content()
{
  return Frame(CONTENT);
}

and so forth for JIT, WASM, SUPPRESSED, etc. along with a private Frame(Kind) constructor would be better?  I guess you'd still want the MOZ_ASSERT in the single-argument Frame constructor, so I'm not totally sure you're winning here.

It would have the advantage of making the construction shorter:

HangStack::Frame::Content()

vs.

HangStack::Frame::Frame(HangStack::Frame::Kind::CONTENT);

Comment 3

[Nika Layzell [:nika] (ni? for response)]

Attachment: Part 2: Switch to using separate static constructor methods for data-free frames

I think this patch should make the change you suggested. It definitely makes the construction sites nicer, but increases the amount of code a decent amount. What do you think of it?

Comment 4

[Nathan Froyd [:froydnj]]

Comment on attachment 8902335 [details] [diff] [review]
Part 2: Switch to using separate static constructor methods for data-free frames

Review of attachment 8902335 [details] [diff] [review]:
-----------------------------------------------------------------

I like this better, personally.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/f58b56aa6171
Use a custom Frame::Kind for special BHR frame types, r=froydnj

Comment 6

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/f58b56aa6171