From: Florian Weimer <fweimer@redhat.com>
To: Szabolcs Nagy <szabolcs.nagy@arm.com>
Cc: libc-alpha@sourceware.org,
Michael Kerrisk <mtk.manpages@gmail.com>,
Rich Felker <dalias@libc.org>
Subject: Re: [PATCH v2 2/2] manual: Document __libc_single_threaded
Date: Tue, 30 Jun 2020 10:56:22 +0200 [thread overview]
Message-ID: <878sg5szih.fsf@oldenburg2.str.redhat.com> (raw)
In-Reply-To: <20200625120854.GI16726@arm.com> (Szabolcs Nagy's message of "Thu, 25 Jun 2020 13:08:55 +0100")
* Szabolcs Nagy:
> linux has several syscalls that change some property of
> the current thread and get inherited by new threads
> (e.g. setxid, various prctls, signal mask) and a user
> may want to set such property for the entire process
> and bail out if that cannot work, so the question is
> if __libc_single_threaded works for this? even if this
> is done in a signal handler? e.g.
>
> if (__libc_single_thread)
> prctl(set_property,a2,a3,a4,a5); // entire process ok
> else
> bailout(); // there might be other threads
>
> i think this may be another valid usage (not related
> to atomics).
In theory, that could be the case, but the question is what you do in
the bailout case.
Thanks,
Florian
next prev parent reply other threads:[~2020-06-30 8:56 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-24 12:59 [PATCH v2 1/2] Add the __libc_single_threaded variable Florian Weimer
2020-06-24 13:03 ` [PATCH v2 2/2] manual: Document __libc_single_threaded Florian Weimer
2020-06-25 12:08 ` Szabolcs Nagy
2020-06-30 8:56 ` Florian Weimer [this message]
2020-06-30 1:06 ` DJ Delorie
2020-06-30 8:57 ` Florian Weimer
2020-06-30 0:52 ` [PATCH v2 1/2] Add the __libc_single_threaded variable DJ Delorie
2020-06-30 9:24 ` Florian Weimer
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