From: David Vrabel <david.vrabel@citrix•com>
To: Zoltan Kiss <zoltan.kiss@citrix•com>,
David Vrabel <david.vrabel@citrix•com>,
Wei Liu <wei.liu2@citrix•com>, <netdev@vger•kernel.org>,
<xen-devel@lists•xen.org>
Cc: Ian Campbell <ian.campbell@citrix•com>
Subject: Re: [Xen-devel] [PATCH net v2 1/3] xen-netback: move NAPI add/remove calls
Date: Mon, 11 Aug 2014 14:01:06 +0100 [thread overview]
Message-ID: <53E8BE92.5070606@citrix.com> (raw)
In-Reply-To: <53E8BBCB.50308@citrix.com>
On 11/08/14 13:49, Zoltan Kiss wrote:
> On 11/08/14 13:35, David Vrabel wrote:
>> On 08/08/14 17:37, Wei Liu wrote:
>>> Originally napi_add was in init_queue and napi_del was in deinit_queue,
>>> while kthreads were handled in _connect and _disconnect. Move napi_add
>>> and napi_remove to _connect and _disconnect so that they reside togother
>>> with kthread operations.
>>>
>>> Signed-off-by: Wei Liu <wei.liu2@citrix•com>
>>> Cc: Ian Campbell <ian.campbell@citrix•com>
>>> Cc: Zoltan Kiss <zoltan.kiss@citrix•com>
>>> ---
>>> drivers/net/xen-netback/interface.c | 12 ++++++++----
>>> 1 file changed, 8 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/net/xen-netback/interface.c
>>> b/drivers/net/xen-netback/interface.c
>>> index 48a55cd..fdb4fca 100644
>>> --- a/drivers/net/xen-netback/interface.c
>>> +++ b/drivers/net/xen-netback/interface.c
>>> @@ -528,9 +528,6 @@ int xenvif_init_queue(struct xenvif_queue *queue)
>>>
>>> init_timer(&queue->rx_stalled);
>>>
>>> - netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll,
>>> - XENVIF_NAPI_WEIGHT);
>>> -
>>> return 0;
>>> }
>>>
>>> @@ -618,6 +615,9 @@ int xenvif_connect(struct xenvif_queue *queue,
>>> unsigned long tx_ring_ref,
>>> wake_up_process(queue->task);
>>> wake_up_process(queue->dealloc_task);
>>>
>>> + netif_napi_add(queue->vif->dev, &queue->napi, xenvif_poll,
>>> + XENVIF_NAPI_WEIGHT);
>>> +
>>> return 0;
>>>
>>> err_rx_unbind:
>>> @@ -675,6 +675,11 @@ void xenvif_disconnect(struct xenvif *vif)
>>>
>>> for (queue_index = 0; queue_index < num_queues; ++queue_index) {
>>> queue = &vif->queues[queue_index];
>>> + netif_napi_del(&queue->napi);
>>> + }
>>
>> Why have you added an additional loop over all the queues? The ordering
>> looks wrong as well. I think you want
>>
>> 1. unbind from irqhandler
>> 2. napi del
>> 3. stop task
>> 4. stop dealloc task
>> 5. unmap frontend rings.
> And that's how they are ordered.
No, it isn't. Did you mistakenly look at netfront which is correctly
ordered already?
You must unbind the irq handler before calling netif_napi_del() or an
interrupt may occur and the handler may call napi_schedule() with a
deleted instance.
David
next prev parent reply other threads:[~2014-08-11 13:01 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-08-08 16:37 [PATCH net v2 0/3] xen-netback: synchronisation between core driver and netback Wei Liu
2014-08-08 16:37 ` [PATCH net v2 1/3] xen-netback: move NAPI add/remove calls Wei Liu
2014-08-08 16:49 ` Sergei Shtylyov
2014-08-08 16:52 ` Wei Liu
2014-08-11 12:35 ` [Xen-devel] " David Vrabel
2014-08-11 12:49 ` Zoltan Kiss
2014-08-11 13:01 ` David Vrabel [this message]
2014-08-11 13:14 ` Zoltan Kiss
2014-08-11 13:43 ` Wei Liu
2014-08-11 13:59 ` David Vrabel
2014-08-11 14:08 ` Wei Liu
2014-08-08 16:37 ` [PATCH net v2 2/3] xen-netback: don't stop dealloc kthread too early Wei Liu
2014-08-11 12:10 ` [Xen-devel] " David Vrabel
2014-08-11 13:48 ` Wei Liu
2014-08-11 13:58 ` David Vrabel
2014-08-11 14:13 ` Zoltan Kiss
2014-08-11 14:44 ` Wei Liu
2014-08-11 15:23 ` David Vrabel
2014-08-11 20:39 ` Wei Liu
2014-08-11 14:31 ` Wei Liu
2014-08-11 14:34 ` David Vrabel
2014-08-11 14:39 ` Wei Liu
2014-08-08 16:37 ` [PATCH net v2 3/3] xen-netback: remove loop waiting function Wei Liu
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=53E8BE92.5070606@citrix.com \
--to=david.vrabel@citrix$(echo .)com \
--cc=ian.campbell@citrix$(echo .)com \
--cc=netdev@vger$(echo .)kernel.org \
--cc=wei.liu2@citrix$(echo .)com \
--cc=xen-devel@lists$(echo .)xen.org \
--cc=zoltan.kiss@citrix$(echo .)com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
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