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From: Florian Weimer <fweimer@redhat.com>
To: Andreas Schwab <schwab@suse.de>
Cc: libc-alpha@sourceware.org
Subject: Re: [PATCH v2] linux: Add #include <sys/rseq.h> to sched_getcpu.c (bug 31479)
Date: Wed, 13 Mar 2024 18:58:33 +0100	[thread overview]
Message-ID: <87edceqaie.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <mvmplvymc0c.fsf@suse.de> (Andreas Schwab's message of "Wed, 13 Mar 2024 15:39:47 +0100")

* Andreas Schwab:

> On Mär 13 2024, Florian Weimer wrote:
>
>> Originally, nptl/descr.h included <sys/rseq.h>, but we removed that
>> in commit 2c6b4b272e6b4d07303af25709051c3e96288f2d ("nptl:
>> Unconditionally use a 32-byte rseq area").
>
> Can't this use rseq_area unconditionally?

Interesting idea.  It adds an extra branch for architectures which are
not rseq-enabled, but they likely lack vDSO acceleration as well and hit
the full system call every time, so it doesn't really matter.

I'll test and send a v3, although I don't think I've got access to any
!RSEQ_SIG architectures.

Thanks,
Florian


      reply	other threads:[~2024-03-13 17:58 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-13 13:08 Florian Weimer
2024-03-13 14:39 ` Andreas Schwab
2024-03-13 17:58   ` Florian Weimer [this message]

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