netdev - Re: [PATCH net-next] net: skb_peek()/skb_peek

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <1336136491.3752.318.camel@edumazet-glaptop>
Date:	Fri, 04 May 2012 15:01:31 +0200
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	David Miller <davem@...emloft.net>
Cc:	netdev@...r.kernel.org
Subject: Re: [PATCH net-next] net: skb_peek()/skb_peek_tail() cleanups

On Tue, 2012-05-01 at 09:41 -0400, David Miller wrote:
> From: Eric Dumazet <eric.dumazet@...il.com>
> Date: Tue, 01 May 2012 04:31:46 +0200
> 
> > From: Eric Dumazet <edumazet@...gle.com>
> > 
> > remove useless casts and rename variables for less confusion.
> > 
> > Signed-off-by: Eric Dumazet <edumazet@...gle.com>
> 
> Applied, I really need to get back to completing the list_head
> conversion :-/

Actually doubly linked lists everywhere has a performance issue.

When we dequeue one skb, we must bring in cpu cache the next skb as
well, to perform the unlink.

In some places it would be better to not have a double linked list, and
only perform a prefetch(skb->next).



--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html