All of lore.kernel.org
 help / color / mirror / Atom feed
From: linas@austin.ibm.com (Linas Vepstas)
To: utz.bacher@de.ibm.com, Arnd Bergmann <arnd.bergmann@de.ibm.com>,
	Maxim Shchetynin <maxim@de.ibm.com>,
	linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2]: Spider ethernet driver -- protect chain head
Date: Fri, 21 Apr 2006 20:03:21 -0500	[thread overview]
Message-ID: <20060422010321.GO7242@austin.ibm.com> (raw)
In-Reply-To: <20060422001140.GA12826@gate.ebshome.net>

On Fri, Apr 21, 2006 at 05:11:40PM -0700, Eugene Surovegin wrote:
> On Fri, Apr 21, 2006 at 06:45:51PM -0500, Linas Vepstas wrote:
> > Prevent a potential race. If two threads are both calling
> > the transmit routine, both can potentially try to grab the
> > same dma descriptor. Serialize access to the head of the
> > tx ring with spinlocks.
> 
> Two threads cannot be in spider_net_xmit() simultaneosuly because 
> hard_start_xmit entry point is already protected by net_device 
> xmit_lock, see Documentation/net/netdevices.txt

Ahh, thank you. I was wondering why I never semmed to see this
this happen in "real life".

--linas

      reply	other threads:[~2006-04-22  1:03 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2006-04-21 23:29 [PATCH 1/2]: Spider ethernet driver spinlocks Linas Vepstas
2006-04-21 23:29 ` Linas Vepstas
2006-04-21 23:45 ` [PATCH 2/2]: Spider ethernet driver -- protect chain head Linas Vepstas
2006-04-21 23:45   ` Linas Vepstas
2006-04-22  0:11   ` Eugene Surovegin
2006-04-22  0:11     ` Eugene Surovegin
2006-04-22  1:03     ` Linas Vepstas [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=20060422010321.GO7242@austin.ibm.com \
    --to=linas@austin.ibm.com \
    --cc=arnd.bergmann@de.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linuxppc-dev@ozlabs.org \
    --cc=maxim@de.ibm.com \
    --cc=utz.bacher@de.ibm.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.