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Subject: Re: smp overhead, and rwlocks considered harmful
From: "David S. Miller" <davem@redhat.com>
To: Andrew Morton <akpm@digeo.com>
Cc: linux-kernel@vger.kernel.org
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On Sat, 2003-03-22 at 17:58, Andrew Morton wrote:
> I've always been a bit skeptical about rwlocks - if you're holding the lock
> for long enough for a significant amount of reader concurrency, you're
> holding it for too long.  eg:  tasklist_lock.

I totally agree with you Andrew, on modern SMP systems rwlocks
are basically worthless.  I think we should kill them off and
convert all instances to spinlocks or some better primitive (perhaps
a more generalized big reader lock, Roman Zippel had something...)

-- 
David S. Miller <davem@redhat.com>
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