WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

[Xen-ia64-devel] [PATCH][RFC] correction trouble of short message in UDP

To: xen-devel <xen-devel@xxxxxxxxxxxxxxxxxxx>
Subject: [Xen-ia64-devel] [PATCH][RFC] correction trouble of short message in UDP
From: Tomonari Horikoshi <t.horikoshi@xxxxxxxxxxxxxx>
Date: Thu, 25 Jan 2007 20:04:10 +0900
Cc: xen-ia64-devel <xen-ia64-devel@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Thu, 25 Jan 2007 03:03:55 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
List-help: <mailto:xen-ia64-devel-request@lists.xensource.com?subject=help>
List-id: Discussion of the ia64 port of Xen <xen-ia64-devel.lists.xensource.com>
List-post: <mailto:xen-ia64-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-ia64-devel>, <mailto:xen-ia64-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-ia64-devel>, <mailto:xen-ia64-devel-request@lists.xensource.com?subject=unsubscribe>
Sender: xen-ia64-devel-bounces@xxxxxxxxxxxxxxxxxxx
Hi all.

I modified the patch to the following trouble.

"When I executed "netperf" by a short message of UDP, 
 PV domain issued Call trace."

This error occurs because earliness grant is filled from 
the queue check of tx_slot when a lot of message is sent. 

I stopped "Add netfornt tx_queue_len" being used, and I was added to check 
gnttab_empty_grant_references() in netfront_tx_slot_available().


I confirmed the not error because of this correction. 
Is there a better correction?


Best regards.

Tomonari Horikoshi,


Tomonari Horikoshi wrote:----------------------
Sent:    Thu, 25 Jan 2007 13:44:30 +0900
Subject: Re: [Xen-devel] [PATCH] Add netfornt tx_queue_len

> Hi Herbert-san
> 
> Thank you for your comment.
> 
> I agreed.
> I examine the another way. 
> 
> It is likely to go well if something is added to the check 
> on netfront_tx_slot_available(). 
> 
> Best regards.
> 
> Tomonari Horikoshi,
> 
> Herbert Xu wrote:----------------------
> Sent:    Wed, 24 Jan 2007 13:29:51 +1100
> Subject: Re: [Xen-devel] [PATCH] Add netfornt tx_queue_len
> 
> > On Wed, Jan 24, 2007 at 01:37:55AM +0000, Tomonari Horikoshi wrote:
> > > 
> > > When I executed "netperf" by a short message of UDP, 
> > > PV domain and PV-on-HVM driver issued Call trace.
> > > 
> > > I think that GrantEntry was filled with a lot of messages processings.
> > > 
> > > This problem is generated in IA64 only.
> > > Probably, I think that I am the following problems. 
> > > 
> > >   In IA64
> > >     NET_TX_RING_SIZE 1024,  NR_GRANT_ENTRIES 2048
> > >   In x86
> > >     NET_TX_RING_SIZE  256,  NR_GRANT_ENTRIES 2048
> > > 
> > > I corrected to check "number of unprocessing queue > tx_queue_len" before 
> > > Grant was filled.
> > > 
> > > However, my correction influences x86. 
> > > Please teach to me in that when there is a better improvement. 
> > 
> > Sorry, but this patch looks bogus.  The tx queue is maintained by
> > Linux and has nothing to do with the driver.  So limiting its length
> > based on internal state of the driver can't be right.
> > 
> > We need to find out what's really going wrong with the grant table
> > entries here.
> > 
> > Cheers,


Attachment: netfront_chk_grant.patch
Description: Binary data

_______________________________________________
Xen-ia64-devel mailing list
Xen-ia64-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-ia64-devel