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From: Lee Revell <rlrevell@joe-job.com>
To: Alain Schroeder <alain@parkautomat.net>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
	Jan-Benedict Glaw <jbglaw@lug-owl.de>
Subject: Re: tun.c patch to fix "smp_processor_id() in preemptible code"
Date: Fri, 15 Oct 2004 18:35:03 -0400	[thread overview]
Message-ID: <1097879702.6737.7.camel@krustophenia.net> (raw)
In-Reply-To: <1097876587.4170.16.camel@marvin.home.parkautomat.net>

On Fri, 2004-10-15 at 17:43, Alain Schroeder wrote:
> I was getting these traces on a SMP host:

Your patch:

+       preempt_disable();
        netif_rx_ni(skb);
+       preempt_enable();

just wraps this code in preempt_disable/enable:

static inline int netif_rx_ni(struct sk_buff *skb)
{
       int err = netif_rx(skb);
       if (softirq_pending(smp_processor_id()))
               do_softirq();
       return err;
}

Isn't this considered an incorrect use of preempt_disable/enable?  My
reasoning is that if this was correct we would see preempt_dis/enable
sprinkled all over the code which it isn't.

Why do you have to call do_softirq like that?  I was under the
impression that you raise a softirq and it gets run later.

Lee


  parent reply	other threads:[~2004-10-15 23:55 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-10-15 21:43 tun.c patch to fix "smp_processor_id() in preemptible code" Alain Schroeder
2004-10-15 22:22 ` Herbert Xu
2004-10-15 22:35 ` Lee Revell [this message]
     [not found]   ` <200410172314.38597.vda@port.imtp.ilyichevsk.odessa.ua>
2004-10-19 18:31     ` Lee Revell
2004-10-19 21:35       ` Herbert Xu
2004-10-19 21:51         ` Lee Revell
2004-10-19 21:54           ` Herbert Xu
2004-10-19 22:10             ` Lee Revell
2004-10-19 22:33               ` David S. Miller
2004-10-19 22:42                 ` Lee Revell
2004-10-19 22:42                   ` David S. Miller
2004-10-19 22:51                     ` Lee Revell
2004-10-20  0:44                       ` David S. Miller

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