1333391 - Move GetCPUCount to threading layer

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect, P3)

Description

[Lars T Hansen [:lth]]

For background see bug 1333059.  The JS engine does not use PR_GetProcessorCount, because it does not use NSPR, instead it has its own definition (GetCPUCount) tucked away in the garbage collector.

Let's move that to js/src/threading so that when the threading layer is lifted into MFBT the GetCPUCount mechanism also appears in MFBT, to potentially benefit all who are currently using their own mechanisms.

Comment 1

[Lars T Hansen [:lth]]

Attachment: bug1333391-getcpucount.patch

(Try runs for this are attached to bug 1333059.)

Comment 2

[Luke Wagner [:luke]]

Comment on attachment 8829831 [details] [diff] [review]
bug1333391-getcpucount.patch

Review of attachment 8829831 [details] [diff] [review]:
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The actual patch seems fine, but I'd wait a bit before landing to see if anyone else involved in js/threading or mfbt wants to comment.

Comment 3

[Nathan Froyd [:froydnj]]

(In reply to Lars T Hansen [:lth] from comment #0)
> Let's move that to js/src/threading so that when the threading layer is
> lifted into MFBT the GetCPUCount mechanism also appears in MFBT, to
> potentially benefit all who are currently using their own mechanisms.

I was thinking about just moving the mutex/condvar implementations themselves; I wasn't going to attempt a full |hg mv|, as there's JS-specific stuff in the mutex/condvar bits that should remain in the JS engine itself.  I don't have any objection to landing something like GetCPUCount, but just note that it may not quickly move into MFBT/mozglue.

Comment 4

[Lars T Hansen [:lth]]

(In reply to Nathan Froyd [:froydnj] from comment #3)
> 
> I was thinking about just moving the mutex/condvar implementations
> themselves; I wasn't going to attempt a full |hg mv|, as there's JS-specific
> stuff in the mutex/condvar bits that should remain in the JS engine itself. 
> I don't have any objection to landing something like GetCPUCount, but just
> note that it may not quickly move into MFBT/mozglue.

Noted.  Putting it into threading/ at least makes it somewhat more visible; getting it moved to mfbt will have to remain our ambition, for now.

Comment 5

[Lars T Hansen [:lth]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/2e13f21663bba2af75c9184966cf24bf56d90dad
Bug 1333391 - move GetCPUCount to the threading layer.  r=luke

Comment 6

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/2e13f21663bb