linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Stefan Hajnoczi <stefanha@gmail.com>
To: Jason Wang <jasowang@redhat.com>
Cc: mst@redhat.com, kvm@vger.kernel.org,
	virtualization@lists.linux-foundation.org,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next V2 3/3] tun: rx batching
Date: Thu, 5 Jan 2017 09:27:50 +0000	[thread overview]
Message-ID: <20170105092750.GA25138@stefanha-x1.localdomain> (raw)
In-Reply-To: <73da2ef8-2454-5614-d637-0ce7c5287433@redhat.com>

[-- Attachment #1: Type: text/plain, Size: 830 bytes --]

On Wed, Jan 04, 2017 at 11:03:32AM +0800, Jason Wang wrote:
> On 2017年01月03日 21:33, Stefan Hajnoczi wrote:
> > On Wed, Dec 28, 2016 at 04:09:31PM +0800, Jason Wang wrote:
> > > +static int tun_rx_batched(struct tun_file *tfile, struct sk_buff *skb,
> > > +			  int more)
> > > +{
> > > +	struct sk_buff_head *queue = &tfile->sk.sk_write_queue;
> > > +	struct sk_buff_head process_queue;
> > > +	int qlen;
> > > +	bool rcv = false;
> > > +
> > > +	spin_lock(&queue->lock);
> > Should this be spin_lock_bh()?  Below and in tun_get_user() there are
> > explicit local_bh_disable() calls so I guess BHs can interrupt us here
> > and this would deadlock.
> 
> sk_write_queue were accessed only in this function which runs under process
> context, so no need for spin_lock_bh() here.

I see, thanks!

Stefan

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 455 bytes --]

      reply	other threads:[~2017-01-05  9:28 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-12-28  8:09 [PATCH net-next V2 0/3] vhost net tx batching Jason Wang
2016-12-28  8:09 ` [PATCH net-next V2 1/3] vhost: better detection of available buffers Jason Wang
2017-01-03 13:08   ` Stefan Hajnoczi
2016-12-28  8:09 ` [PATCH net-next V2 2/3] vhost_net: tx batching Jason Wang
2017-01-03 13:16   ` Stefan Hajnoczi
2016-12-28  8:09 ` [PATCH net-next V2 3/3] tun: rx batching Jason Wang
2016-12-29 16:35   ` David Miller
2016-12-30  5:14     ` Jason Wang
2017-01-03 13:33   ` Stefan Hajnoczi
2017-01-04  3:03     ` Jason Wang
2017-01-05  9:27       ` Stefan Hajnoczi [this message]

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=20170105092750.GA25138@stefanha-x1.localdomain \
    --to=stefanha@gmail.com \
    --cc=jasowang@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mst@redhat.com \
    --cc=netdev@vger.kernel.org \
    --cc=virtualization@lists.linux-foundation.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).