archive mirror
 help / color / mirror / Atom feed
From: Pablo Neira Ayuso <>
To: Aleksander Jan Bajkowski <>
Subject: Re: [PATCH nf] Revert "netfilter: flowtable: Remove redundant hw refresh bit"
Date: Mon, 14 Jun 2021 23:53:51 +0200	[thread overview]
Message-ID: <20210614215351.GA734@salvia> (raw)
In-Reply-To: <>


On Mon, Jun 14, 2021 at 09:34:40PM +0200, Aleksander Jan Bajkowski wrote:
> This reverts commit c07531c01d8284aedaf95708ea90e76d11af0e21.
> The previously mentioned commit significantly reduces NAT performance
> in OpenWRT. Another user reports a high ping issue. The results of
> IPv4 NAT benchmark on BT Home Hub 5A (with software flow offloading):
> * 5.4.124             515 Mb/s
> * 5.10.41             570 Mb/s
> * 5.10.42             250 Mb/s
> * 5.10.42 + revert    580 Mb/s
> Reverting this commit fixes this issue.

The xt_flowoffload module is inconditionally setting on the hardware
offload flag:

static int __init xt_flowoffload_tg_init(void)
       int ret;


       ret = init_flowtable(&flowtable[0]);
       if (ret)
               return ret;

       ret = init_flowtable(&flowtable[1]);
       if (ret)
               goto cleanup;

       flowtable[1].ft.flags = NF_FLOWTABLE_HW_OFFLOAD;

which is triggering the slow down because packet path is allocating
work to offload the entry to hardware, however, this driver does not
support for hardware offload.

Probably this module can be updated to unset the flowtable flag if the
harware does not support hardware offload.

  reply	other threads:[~2021-06-14 21:55 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-06-14 19:34 [PATCH nf] Revert "netfilter: flowtable: Remove redundant hw refresh bit" Aleksander Jan Bajkowski
2021-06-14 21:53 ` Pablo Neira Ayuso [this message]
2021-07-11  1:02   ` Martin Blumenstingl
2021-07-11 12:33     ` Aleksander Bajkowski
2021-07-12  9:46     ` Pablo Neira Ayuso
2021-07-12 10:18       ` Felix Fietkau

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:

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

  git send-email \
    --in-reply-to=20210614215351.GA734@salvia \ \ \ \ \ \ \ \ \ \ \ \

* 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).