Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 16 Nov 2002 13:08:58 -0500 (EST)
From:      Daniel Eischen <eischen@pcnet1.pcnet.com>
To:        Marcel Moolenaar <marcel@FreeBSD.org>
Cc:        cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org
Subject:   Re: cvs commit: src/lib/libc_r/arch/ia64 _atomic_lock.S
Message-ID:  <Pine.GSO.4.10.10211161308020.20425-100000@pcnet1.pcnet.com>
In-Reply-To: <200211161705.gAGH56v5058239@repoman.freebsd.org>

next in thread | previous in thread | raw e-mail | index | archive | help
On Sat, 16 Nov 2002, Marcel Moolenaar wrote:

> marcel      2002/11/16 09:05:06 PST
> 
>   Modified files:
>     lib/libc_r/arch/ia64 _atomic_lock.S 
>   Log:
>   Implement the lock with a cmpxchg instruction instead of a xchg.
>   Both are atomic, but the cmpxchg has memory ordering hints. We
>   give this acquire semantics.
>   
>   NOTE: The unlock in libc_r is implemented by a "normal" assign
>   statement. This is not correct on ia64 due to the memory ordering
>   characteristics of the architecture. We need release semantics
>   for an unlock.

We can fix that before 5.0 goes out.

-- 
Dan Eischen


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe cvs-all" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.GSO.4.10.10211161308020.20425-100000>