netdev - Re: [PATCH 0/2] AF_PACKET fanout 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: Windows password security audit tool. GUI, reports in PDF.

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

Message-Id: <20110705.201950.199250194399828543.davem@davemloft.net>
Date:	Tue, 05 Jul 2011 20:19:50 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	therbert@...gle.com
Cc:	victor@...iniac.net, netdev@...r.kernel.org, willemb@...gle.com
Subject: Re: [PATCH 0/2] AF_PACKET fanout support

From: Tom Herbert <therbert@...gle.com>
Date: Tue, 5 Jul 2011 20:13:27 -0700

>>> Also, another useful mode of steering would be to steer packets to a
>>> socket which was recently processed by a thread running on the same
>>> CPU; somewhat analogous to RFS (cc'ed WIllem Bruijn who is already
>>> working on this I believe).
>>
>> This sounds like a good way to overload a local socket and prevent
>> pushing the work to lesser used sockets on other cpus.
>>
> Sure, it you're not using RPS or RSS!  These should already be
> distributing the RX work amongst CPUs.

One idea I did have while working on the PACKET_FANOUT bits was
to allow a packet socket to be bound to a particular cpu.  And
to implement this we'd have a per-cpu list of packet_type taps.

But in order for the user to make sure he gets all the traffic,
he'd have to make sure he bound one AF_PACKET socket to every
online cpu and then listened for all cpu hotplug events.

It doesn't really work.
--
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