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Date: Wed, 4 Aug 2004 23:02:44 -0400
From: Brian Fundakowski Feldman <green@FreeBSD.org>
To: Robert Watson <rwatson@FreeBSD.org>
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Subject: Re: cvs commit: src/sys/net bpf.c
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On Thu, Aug 05, 2004 at 02:37:36AM +0000, Robert Watson wrote:
> rwatson     2004-08-05 02:37:36 UTC
> 
>   FreeBSD src repository
> 
>   Modified files:
>     sys/net              bpf.c 
>   Log:
>   Do a lockless read of the BPF interface structure descriptor list head
>   before grabbing BPF locks to see if there are any entries in order to
>   avoid the cost of locking if there aren't any.  Avoids a mutex lock/
>   unlock for each packet received if there are no BPF listeners.

While you're there, do you want to check out the other problems I've been
noticing, relating to consistency/locking?

-- 
Brian Fundakowski Feldman                           \'[ FreeBSD ]''''''''''\
  <> green@FreeBSD.org                               \  The Power to Serve! \
 Opinions expressed are my own.                       \,,,,,,,,,,,,,,,,,,,,,,\