netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: David Howells <dhowells@redhat.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: dhowells@redhat.com, netdev@vger.kernel.org,
	linux-afs@lists.infradead.org, linux-kernel@vger.kernel.org,
	Paolo Abeni <pabeni@redhat.com>
Subject: Re: [PATCH net 2/2] rxrpc: Fix the data_ready handler
Date: Fri, 05 Oct 2018 17:33:20 +0100	[thread overview]
Message-ID: <25989.1538757200@warthog.procyon.org.uk> (raw)
In-Reply-To: <80cf9647-ffdf-210a-7b0e-22bf35a57239@gmail.com>

Eric Dumazet <eric.dumazet@gmail.com> wrote:

> sk_data_ready is not meant to process packets, it is meant to signal
> to another entity (preferably running in process context and thus with proper
> schedule points, and not blocking BH) that there is data ready to be consumed.

The issue is that I need to route the packets to the appropriate call, and the
BH appears to be the right place to do this, especially as I can quickly parse
and discard certain types of packet right there.

If I move all of this to process context then that adds extra context switches
between the routing process and the destination process.

> Under DOS, it is possible multiple cpus will sk_data_ready in parallel.

Ummm...  I've been led to believe that sk_data_ready will *not* be called in
parallel and that the code it calls can assume non-reentrancy.  Is this not
the case?

What about the patch I attached, whereby I use the encap_rcv() hook.  Do you
say that won't work?

David

  reply	other threads:[~2018-10-05 16:33 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-05 13:42 [PATCH net 0/2] rxrpc: Fixes David Howells
2018-10-05 13:43 ` [PATCH net 1/2] rxrpc: Fix some missed refs to init_net David Howells
2018-10-05 13:43 ` [PATCH net 2/2] rxrpc: Fix the data_ready handler David Howells
2018-10-05 13:52   ` Eric Dumazet
2018-10-05 14:18     ` David Howells
2018-10-05 16:07       ` Eric Dumazet
2018-10-05 16:33         ` David Howells [this message]
2018-10-05 17:44           ` Eric Dumazet

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=25989.1538757200@warthog.procyon.org.uk \
    --to=dhowells@redhat.com \
    --cc=eric.dumazet@gmail.com \
    --cc=linux-afs@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=pabeni@redhat.com \
    /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).