From: u-uy74@aetey.se
To: musl@lists.openwall.com
Subject: Re: setcontext/getcontext/makecontext missing?
Date: Fri, 5 Feb 2016 10:58:35 +0100 [thread overview]
Message-ID: <20160205095835.GH25193@example.net> (raw)
In-Reply-To: <20160204192403.GR9349@brightrain.aerifal.cx>
On Thu, Feb 04, 2016 at 02:24:03PM -0500, Rich Felker wrote:
> > Pthreads feels like an overkill, hardly efficient when all one needs
> > is cooperative threading designed from the beginning to fit in one
> > process.
> the comparison is not between pure-userspace switching and having the
> kernel involved, but between a SYS_rt_sigprocmask syscall and a
> voluntary context switch between threads in the same process. The
> latter is extremely light and comparable to some of the cheapest
> syscalls, so I suspect the performance difference between ucontext and
> threads is negligible.
Thanks for pointing this out, if rt_sigprocmask can not be skipped
then indeed a switch becomes much more expensive.
> Given that there are a lot of other good
> reasons you should be using threads instead of ucontext, I think the
> matter is pretty clear.
Sure, the API was not exactly well thought-out.
Still I'd like to have a lighweight choice when it is enough.
This is of course offtopic for musl, given that there is no reasonable
standard/specification for the purpose.
Regards,
Rune
next prev parent reply other threads:[~2016-02-05 9:58 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-04 14:09 Short, Todd
2016-02-04 14:54 ` Szabolcs Nagy
2016-02-04 15:41 ` Rich Felker
2016-02-04 16:22 ` u-uy74
2016-02-04 17:01 ` Szabolcs Nagy
2016-02-05 9:21 ` u-uy74
2016-02-04 19:24 ` Rich Felker
2016-02-05 9:58 ` u-uy74 [this message]
2016-02-07 5:20 ` Justin Cormack
2016-02-07 10:05 ` u-uy74
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