netdev - Re: Add NAPI support to ll

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: <1303215925.3464.54.camel@localhost>
Date:	Tue, 19 Apr 2011 13:25:25 +0100
From:	Ben Hutchings <bhutchings@...arflare.com>
To:	Eric Dumazet <eric.dumazet@...il.com>
Cc:	monstr@...str.eu, netdev@...r.kernel.org
Subject: Re: Add NAPI support to ll_temac driver

On Tue, 2011-04-19 at 12:43 +0200, Eric Dumazet wrote:
[...]
> One possible way to get better performance is to change driver to
> allocate skbs only right before calling netif_rx(), so that you dont
> have to access cold sk_buff data twice (once when allocating skb and put
> it in ring buffer, a second time when receiving frame)
>
> drivers/net/niu.c is a good example for this (NAPI + netdev_alloc_skb()
> just in time + pull in skbhead only first cache line of packet)
[...]

If the hardware can do RX checksumming (it's not clear) then the driver
should pass the paged buffers into GRO and that will take care of skb
allocation as necessary.

Ben.

-- 
Ben Hutchings, Senior Software Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

--
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