netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Daniel Borkmann <dborkman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
To: Thomas Graf <tgraf-G/eBtMaohhA@public.gmane.org>
Cc: dev-yBygre7rU0TnMu66kgdUjQ@public.gmane.org,
	netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org,
	eric.dumazet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org
Subject: Re: [PATCH 2/2 net-next] openvswitch: Use skb_zerocopy() for upcall
Date: Fri, 08 Nov 2013 12:24:21 +0100	[thread overview]
Message-ID: <527CC9E5.2070303@redhat.com> (raw)
In-Reply-To: <9369d871e13fe5b6e468b269450b9f2032a970aa.1383906944.git.tgraf-G/eBtMaohhA@public.gmane.org>

On 11/08/2013 11:47 AM, Thomas Graf wrote:
> Use of skb_zerocopy() avoids the expensive call to memcpy() when
> copying the packet data into the Netlink skb. Completes checksum
> through skb_checksum_help() if needed.
>
> Netlink messaged must be properly padded and aligned to meet
> sanity checks of the user space counterpart.
>
> Cost of memcpy is significantly reduced from:
> +   7.48%       vhost-8471  [k] memcpy
> +   5.57%     ovs-vswitchd  [k] memcpy
> +   2.81%       vhost-8471  [k] csum_partial_copy_generic
>
> to:
> +   5.72%     ovs-vswitchd  [k] memcpy
> +   3.32%       vhost-5153  [k] memcpy
> +   0.68%       vhost-5153  [k] skb_zerocopy
>
> (megaflows disabled)
>
> Signed-off-by: Thomas Graf <tgraf-G/eBtMaohhA@public.gmane.org>
> Cc: Jesse Gross <jesse-l0M0P4e3n4LQT0dZR+AlfA@public.gmane.org>
> Cc: Eric Dumazet <eric.dumazet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>

Reviewed-by: Daniel Borkmann <dborkman-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>

  parent reply	other threads:[~2013-11-08 11:24 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-11-08 10:47 [PATCH 0/2 v4] Open vSwitch zerocopy upcall Thomas Graf
2013-11-08 10:47 ` [PATCH 1/2 net-next] net: Export skb_zerocopy() to zerocopy from one skb to another Thomas Graf
     [not found]   ` <107fca409db2405bf3c650a03ea2254d3d6b63dc.1383906944.git.tgraf-G/eBtMaohhA@public.gmane.org>
2013-11-08 11:06     ` Daniel Borkmann
2013-11-08 10:47 ` [PATCH 2/2 net-next] openvswitch: Use skb_zerocopy() for upcall Thomas Graf
     [not found]   ` <9369d871e13fe5b6e468b269450b9f2032a970aa.1383906944.git.tgraf-G/eBtMaohhA@public.gmane.org>
2013-11-08 11:24     ` Daniel Borkmann [this message]
2013-11-14  7:13 ` [PATCH 0/2 v4] Open vSwitch zerocopy upcall David Miller
     [not found]   ` <20131114.021357.2293924326693299062.davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org>
2013-11-15  9:34     ` Jesse Gross
  -- strict thread matches above, loose matches on Subject: below --
2013-11-08  9:15 [PATCH 0/2 v3] " Thomas Graf
2013-11-08  9:15 ` [PATCH 2/2 net-next] openvswitch: Use skb_zerocopy() for upcall Thomas Graf
2013-11-09 22:02   ` Ben Hutchings
     [not found]     ` <1384034549.3802.41.camel-/LGg1Z1CJKQ+9kgCwbf1HqK4ta4zdZpAajtMo4Cw6ucAvxtiuMwx3w@public.gmane.org>
2013-11-10 23:40       ` Thomas Graf
2013-11-11  1:55         ` Jesse Gross

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=527CC9E5.2070303@redhat.com \
    --to=dborkman-h+wxahxf7alqt0dzr+alfa@public.gmane.org \
    --cc=davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org \
    --cc=dev-yBygre7rU0TnMu66kgdUjQ@public.gmane.org \
    --cc=eric.dumazet-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \
    --cc=netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=tgraf-G/eBtMaohhA@public.gmane.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).