public inbox for netdev@vger.kernel.org 
 help / color / mirror / Atom feed
From: John Fastabend <john.fastabend@gmail•com>
To: Eric Dumazet <edumazet@google•com>,
	"David S . Miller" <davem@davemloft•net>
Cc: netdev <netdev@vger•kernel.org>,
	Willem de Bruijn <willemb@google•com>,
	Adam Belay <abelay@google•com>, Zach Brown <zach.brown@ni•com>,
	Tariq Toukan <tariqt@mellanox•com>,
	Yuval Mintz <Yuval.Mintz@cavium•com>,
	Ariel Elior <ariel.elior@cavium•com>,
	Eric Dumazet <eric.dumazet@gmail•com>
Subject: Re: [PATCH net-next 0/5] net: busy-poll: allow preemption and other optimizations
Date: Wed, 16 Nov 2016 10:03:43 -0800	[thread overview]
Message-ID: <582C9F7F.2070807@gmail.com> (raw)
In-Reply-To: <1479233715-9905-1-git-send-email-edumazet@google.com>

On 16-11-15 10:15 AM, Eric Dumazet wrote:
> It is time to have preemption points in sk_busy_loop() and improve
> its scalability.
> 
> Also napi_complete() and friends can tell drivers when it is safe to
> not re-enable device interrupts, saving some overhead under
> high busy polling.
> 
> mlx4 and bnx2x are changed accordingly, to show how this busy polling
> status can be exploited by drivers.
> 
> Next steps will implement Zach Brown suggestion, where NAPI polling
> would be enabled all the time for some chosen queues.
> This is needed for efficient epoll() support anyway.

Would you expect to make this a per queue option of the hardware
configured via ethtool/netlink/sysfs and like where users steer traffic
to particular queues using existing ntuple filters or 'tc' or infer it
from the socket layer?

So configuration would be (a) enable busy-polling on queues x,y,z and
then (b) use ntuple/RSS/etc to steer relative traffic to queues. In
this case traffic doesn't need to be bound to a socket in any way.
Seems like a useful generalization.

Thanks,
John

> 
> Eric Dumazet (5):
>   net: busy-poll: allow preemption in sk_busy_loop()
>   net: busy-poll: remove need_resched() from sk_can_busy_loop()
>   net: busy-poll: return busypolling status to drivers
>   net/mlx4_en: use napi_complete_done() return value
>   bnx2x: switch to napi_complete_done()
> 
>  drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c |  15 ++--
>  drivers/net/ethernet/mellanox/mlx4/en_rx.c      |   4 +-
>  include/linux/netdevice.h                       |  17 +++-
>  include/net/busy_poll.h                         |   5 +-
>  net/core/dev.c                                  | 110 +++++++++++++++++++-----
>  5 files changed, 113 insertions(+), 38 deletions(-)
> 

  parent reply	other threads:[~2016-11-16 18:04 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-11-15 18:15 [PATCH net-next 0/5] net: busy-poll: allow preemption and other optimizations Eric Dumazet
2016-11-15 18:15 ` [PATCH net-next 1/5] net: busy-poll: allow preemption in sk_busy_loop() Eric Dumazet
2016-11-15 18:15 ` [PATCH net-next 2/5] net: busy-poll: remove need_resched() from sk_can_busy_loop() Eric Dumazet
2016-11-15 18:15 ` [PATCH net-next 3/5] net: busy-poll: return busypolling status to drivers Eric Dumazet
2016-11-15 18:15 ` [PATCH net-next 4/5] net/mlx4_en: use napi_complete_done() return value Eric Dumazet
2016-11-15 18:15 ` [PATCH net-next 5/5] bnx2x: switch to napi_complete_done() Eric Dumazet
2016-11-16 18:03 ` John Fastabend [this message]
2016-11-16 18:41 ` [PATCH net-next 0/5] net: busy-poll: allow preemption and other optimizations David Miller

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=582C9F7F.2070807@gmail.com \
    --to=john.fastabend@gmail$(echo .)com \
    --cc=Yuval.Mintz@cavium$(echo .)com \
    --cc=abelay@google$(echo .)com \
    --cc=ariel.elior@cavium$(echo .)com \
    --cc=davem@davemloft$(echo .)net \
    --cc=edumazet@google$(echo .)com \
    --cc=eric.dumazet@gmail$(echo .)com \
    --cc=netdev@vger$(echo .)kernel.org \
    --cc=tariqt@mellanox$(echo .)com \
    --cc=willemb@google$(echo .)com \
    --cc=zach.brown@ni$(echo .)com \
    /path/to/YOUR_REPLY

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