From: Rich Felker <dalias@libc.org>
To: musl@lists.openwall.com
Subject: Re: [PATCH] Use CAS instead of atomic swap to implement spinlock
Date: Tue, 14 Apr 2015 19:16:27 -0400 [thread overview]
Message-ID: <20150414231627.GR6817@brightrain.aerifal.cx> (raw)
In-Reply-To: <1429051493-2821-1-git-send-email-amonakov@ispras.ru>
On Wed, Apr 15, 2015 at 01:44:53AM +0300, Alexander Monakov wrote:
> This should allow spinning without constantly dirtying cache lines holding the
> spinlock value. On architectures without native atomic swap, musl implement
> a_swap by looping around a_cas.
It won't help on x86, where all lock-prefixed ops perform both a read
and a write even if they fail. But it should help in ll/sc style
archs, and shouldn't hurt on x86.
Rich
next prev parent reply other threads:[~2015-04-14 23:16 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-04-14 22:44 Alexander Monakov
2015-04-14 23:16 ` Rich Felker [this message]
2015-04-15 6:29 ` Concerns about dlclose() behaviour Brad Conroy
2015-04-15 7:17 ` Rich Felker
2015-04-19 0:24 ` [PATCH] Use CAS instead of atomic swap to implement spinlock Rich Felker
2015-04-19 5:50 ` Alexander Monakov
2015-04-19 6:01 ` Rich Felker
2015-04-19 12:46 ` Szabolcs Nagy
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