netdev - Re: [PATCHv5] virtio-spec: virtio network device RFS support

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 for Android: free password hash cracker in your pocket

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

Message-ID: <1354739966.2655.25.camel@bwh-desktop.uk.solarflarecom.com>
Date:	Wed, 5 Dec 2012 20:39:26 +0000
From:	Ben Hutchings <bhutchings@...arflare.com>
To:	"Michael S. Tsirkin" <mst@...hat.com>
CC:	Jason Wang <jasowang@...hat.com>, <rusty@...tcorp.com.au>,
	<virtualization@...ts.linux-foundation.org>,
	<netdev@...r.kernel.org>, <kvm@...r.kernel.org>
Subject: Re: [PATCHv5] virtio-spec: virtio network device RFS support

On Mon, 2012-12-03 at 12:58 +0200, Michael S. Tsirkin wrote:
> Add RFS support to virtio network device.
> Add a new feature flag VIRTIO_NET_F_RFS for this feature, a new
> configuration field max_virtqueue_pairs to detect supported number of
> virtqueues as well as a new command VIRTIO_NET_CTRL_RFS to program
> packet steering for unidirectional protocols.
[...]
> +Programming of the receive flow classificator is implicit.
> + Transmitting a packet of a specific flow on transmitqX will cause incoming
> + packets for this flow to be steered to receiveqX.
> + For uni-directional protocols, or where no packets have been transmitted
> + yet, device will steer a packet to a random queue out of the specified
> + receiveq0..receiveqn.
[...]

It doesn't seem like this is usable to implement accelerated RFS in the
guest, though perhaps that doesn't matter.  On the host side, presumably
you'll want vhost_net to do the equivalent of sock_rps_record_flow() -
only without a socket?  But in any case, that requires an rxhash, so I
don't see how this is supposed to work.

Ben.

-- 
Ben Hutchings, Staff 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