netdev - Re: Generic rx-recycling and emergency skb pool

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]

Date:	Sat, 03 Jul 2010 09:31:00 +0200
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	David Miller <davem@...emloft.net>
Cc:	sebastian@...akpoint.cc, netdev@...r.kernel.org, tglx@...utronix.de
Subject: Re: Generic rx-recycling and emergency skb pool

Le vendredi 02 juillet 2010 à 23:46 -0700, David Miller a écrit :
> From: Eric Dumazet <eric.dumazet@...il.com>
> Date: Sat, 03 Jul 2010 08:23:25 +0200
> 
> > Maybe its time to provide new API, so that a driver can build an skb at
> > the time RX interrupt is handled, not at the time the rx ring buffer is
> > renewed. RX ring should only provide the data part to NIC, and skb
> > should be built when NIC delivers the frame, so that we provide to IP
> > stack a real hot skb.
> 
> Drivers do this already, and in fact I am very sure I'm mentioned this
> to you at least other time in the past, and one such driver is NIU :-)

You did indeed. I should said "provide a generic and universal API",
usable by average NIC driver, not only big ones. (NIU is more than
10.000 lines of code ;) )

NIU still uses netdev_alloc_skb() API. I was thinking of a function to
allocate and populate the sk_buff, but data part provided by caller.

> 
> It's trivial to do with devices which work on power-of-2 chopped up
> pages.  In fact I'm surprised that RX buffer management scheme is
> not more prevalent in network devices.

Many of them were written in last century :)



--
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