2036234 - Use pthread API to retrieve stack top on non-Android Linux

Status: RESOLVED FIXED

(Core :: Gecko Profiler, task)

Description

[Rong Bao [:csmantle]]

Currently, we only use OS-provided facilities to retrieve the top address of the stack on Windows and Darwin kernels, and use a guessed value on Linux [^0]. Linux also provides Darwin-like functions, pthread_getattr_np(3) [^1] and pthread_attr_getstack(3) [^2] for this purpose. If we can use them, we won't have to guess on Linux.

Paul [:padenot] (CC'd below) raised a concern about the potential blockage of sched_setaffinity(2) by the sandbox [^3]. However, as Jed [:jld] (also CC'd below) pointed out, this isn't a big problem as of the current glibc v2.43, since it will simply give up setting this value [^4].

I'm not very familiar with Android, so I'm limiting the scope of this bug to non-Android Linux for now.

Comment 1

[Rong Bao [:csmantle]]

Attachment: Bug 2036234 - Use pthread API to retrieve stack top on non-Android Linux. r=#profiler-reviewers!,padenot!,jld!

Comment 2

[Jed Davis [:jld] ⟨⏰|UTC-7⟩ ⟦he/him⟧]

(In reply to Rong Bao [:csmantle] from comment #0)

However, as Jed [:jld] (also CC'd below) pointed out, this isn't a big problem as of the current glibc v2.43

For what it's worth, I checked git blame and apparently it's been like that since affinity support was added in 2003.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://github.com/mozilla-firefox/firefox/commit/afcd623846a3
https://hg.mozilla.org/integration/autoland/rev/4309c2c7762a
Use pthread API to retrieve stack top on non-Android Linux. r=padenot,jld,profiler-reviewers,mstange

Comment 4

[Cosmin Sabou [:CosminS]]

https://hg.mozilla.org/mozilla-central/rev/4309c2c7762a