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From: Sergei Shtylyov <sshtylyov@ru.mvista.com>
To: Linux-MIPS <linux-mips@linux-mips.org>
Cc: compudj@krystal.dyndns.org, tt-dev@shafik.org
Subject: [Fwd: [Ltt-dev] MIPS atomic operations, "sync"]
Date: Fri, 10 Nov 2006 21:39:44 +0300	[thread overview]
Message-ID: <4554C770.10106@ru.mvista.com> (raw)

Forwarding to the correct mail list...

-------- Original Message --------
Subject: [Ltt-dev] MIPS atomic operations, "sync"
Date: Fri, 10 Nov 2006 13:36:53 -0500
From: Mathieu Desnoyers <compudj@krystal.dyndns.org>
To: lkml@vger.kernel.org, ltt-dev@shafik.org

Hi,

I am currently creating a "LOCK" prefix free and memory barrier free version
of atomic.h to fulfill my tracer (LTTng) needs, which is to atomically update
per-cpu data and have a minimal performance loss.

I just came across the MIPS atomic.h and system.h implementations in 2.6.18
which brings a question :

Why are the primitives in include/asm-mips/atomic.h using the "sync"
instruction even in the UP case ? system.h cmpxchg only uses the sync in the
SMP case.

Mathieu


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             reply	other threads:[~2006-11-10 18:40 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-11-10 18:39 Sergei Shtylyov [this message]
  -- strict thread matches above, loose matches on Subject: below --
2006-11-10 21:51 [Fwd: [Ltt-dev] MIPS atomic operations, "sync"] Kaz Kylheku
2006-11-10 21:51 ` Kaz Kylheku

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