Re: [Xen-devel] [PATCH resend] xen-netback: switch to threaded irq for control ring

On 22/09/16 12:31, Paul Durrant wrote:

quoted

-----Original Message-----
From: Juergen Gross [mailto:jgross@suse.com]
Sent: 22 September 2016 11:17
To: Paul Durrant <redacted>; xen-devel@lists.xenproject.org;
netdev@vger.kernel.orga [off-list ref]; linux-
kernel@vger.kernel.org
Cc: Wei Liu <redacted>
Subject: Re: [Xen-devel] [PATCH resend] xen-netback: switch to threaded irq
for control ring

On 22/09/16 11:09, Paul Durrant wrote:

quoted

quoted

-----Original Message-----
From: Xen-devel [mailto:xen-devel-bounces@lists.xen.org] On Behalf Of
Juergen Gross
Sent: 22 September 2016 10:03
To: xen-devel@lists.xenproject.org; netdev@vger.kernel.orga; linux-
kernel@vger.kernel.org
Cc: Juergen Gross <jgross@suse.com>; Wei Liu <redacted>
Subject: [Xen-devel] [PATCH resend] xen-netback: switch to threaded
irq for control ring

Instead of open coding it use the threaded irq mechanism in xen-netback.

Signed-off-by: Juergen Gross <jgross@suse.com>

How have you tested this change?

Only compile-tested and loaded the module. As this feature isn't being used
in linux netfront AFAIK it is not easily testable. OTOH the code modification is
rather limited and I've used the threaded irq in the Xen scsiback driver
myself, so I'm rather confident it will work.

OK. How about doing the rx interrupt/task too so that it can be easily tested with a linux netfront?

I'd like to, but this would require some more work. The rx kthread isn't
activated by an event only, but by a timer, too. This isn't easy to map
to the threaded irq framework. If, however, you are confident the timer
isn't really necessary I'd be happy to provide a patch switching the
rx task to the threaded irq, too.

And to be honest: this wouldn't verify that the control ring related
patch is really working. The mechanism itself _is_ working as it is
already in use in xen-scsiback in a very similar environment.


Juergen