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Date: Sat, 30 Oct 2010 10:45:37 -0700 (PDT)
From: Davide Libenzi <davidel@xmailserver.org>
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To: Eric Dumazet <eric.dumazet@gmail.com>
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        Alban Crequy <alban.crequy@collabora.co.uk>,
        "David S. Miller" <davem@davemloft.net>,
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        Pauli Nieminen <pauli.nieminen@collabora.co.uk>,
        Rainer Weikusat <rweikusat@mssgmbh.com>
Subject: Re: [PATCH] af_unix: optimize unix_dgram_poll()
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On Sat, 30 Oct 2010, Eric Dumazet wrote:

> Le vendredi 29 octobre 2010 à 13:46 -0700, Davide Libenzi a écrit :
> 
> > Also, why not using the existing wait->key instead of adding a poll2()?
> 
> Indeed, if wait is not null, we have in wait->key the interest of
> poller. If a particular poll() function is expensive, it can test these
> bits.
> 
> Thanks !
> 
> Note: I chose the 'goto skip_write' to make this patch really obvious.

Plain agreement on th patch, and I understand the indent overflow 
concerns, but why not ...

	/*
	 * No write status requested, avoid expensive OUT tests.
	 */
	if (wait && !(wait->key & (POLLWRBAND | POLLWRNORM | POLLOUT)))
		return mask

The write-test code is the last one we do anyway.


- Davide


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