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Date: Thu, 26 Sep 2002 07:41:40 -0700 (PDT)
From: Linus Torvalds <torvalds@transmeta.com>
To: Andrew Morton <akpm@digeo.com>
cc: "David S. Miller" <davem@redhat.com>, <linux-kernel@vger.kernel.org>
Subject: Re: [patch 1/4] prepare_to_wait/finish_wait sleep/wakeup API
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On Wed, 25 Sep 2002, Andrew Morton wrote:
> 
> I expect a decent win would come from using this technique in
> select/poll, but that code relies on the remains-on-the-waitqueue
> semantics, and would need some fiddling.

Actually, I think that select/poll is exactly the kind of thing that would 
_not_ improve noticeably, since usually it's only one (out of possibly 
hundreds) or wait-queues that gets woken up. 

So even if that one were to be made faster, the _real_ cost when it comes
to the wait-queues will be all the other 99 waitqueues that select/poll
has to remove itself from the old way anyway.

			Linus

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