From: Zoltan Kiss <zoltan.kiss@citrix.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
"xen-devel@lists.xenproject.org" <xen-devel@lists.xenproject.org>,
Malcolm Crossley <malcolm.crossley@citrix.com>,
Jonathan Davies <Jonathan.Davies@citrix.com>,
Paul Durrant <Paul.Durrant@citrix.com>,
Wei Liu <wei.liu2@citrix.com>,
Ian Campbell <Ian.Campbell@citrix.com>
Subject: Re: NAPI rescheduling and the delay caused by it
Date: Wed, 11 Dec 2013 18:52:21 +0000 [thread overview]
Message-ID: <52A8B465.60304@citrix.com> (raw)
In-Reply-To: <1386638065.30495.338.camel@edumazet-glaptop2.roam.corp.google.com>
On 10/12/13 01:14, Eric Dumazet wrote:
> On Mon, 2013-12-09 at 23:39 +0000, Zoltan Kiss wrote:
>> I found another suspect however: my grant mapping patches do the
>> unmapping from the NAPI instance where otherwise we receive the
>> packets from the guest. But this means we call napi_schedule from the
>> zerocopy callback, which can be run by anyone who free up that skb,
>> including an another VIF's RX thread (which actually does the transmit
>> TO the guest). I guess that might be bad.
>
> Same problem : napi_schedule() is meant to be used from interrupt
> context.
Indeed, avoiding napi_schedule seems to solve the issue. Thanks for the
advices!
Zoli
prev parent reply other threads:[~2013-12-11 18:52 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-12-04 18:55 NAPI rescheduling and the delay caused by it Zoltan Kiss
2013-12-04 20:41 ` Eric Dumazet
2013-12-04 21:23 ` Zoltan Kiss
2013-12-04 23:32 ` Eric Dumazet
2013-12-09 23:39 ` Zoltan Kiss
2013-12-10 1:14 ` Eric Dumazet
2013-12-10 1:17 ` Eric Dumazet
2013-12-11 18:52 ` Zoltan Kiss [this message]
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