From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: [PATCH] fix netfront alloc_page error handling bug,
 need to raise up rx_refill timer if rx request buffer not big
 enough for backend
Date: Thu, 14 Nov 2013 11:38:03 +0000
Message-ID: <5284B61B.5030604@citrix.com>
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To: annie li <annie.li@oracle.com>
Cc: Ma JieYue <jieyue.majy@aliyun-inc.com>, xen-devel@lists.xen.org
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On 14/11/13 02:39, annie li wrote:
> 
> With this assumption, is it easier to fix this issue by moving mod_timer
> directly
>             mod_timer(&np->rx_refill_timer,
>                   jiffies + (HZ/10));
> above
>             if (i != 0)
>                 goto refill;
> 
> in xennet_alloc_rx_buffers?

Yes, always setting the timer if we didn't reach the target is a better
fix I think.

However, we probably want to reduce the fill target if we are under
memory pressure.

Something like:

no_skb:
               /* Memory pressure, reduce fill target. */
	       if (--np->rx_target < np->rx_target_min)
                   np->rx_target = np->rx_target_min;
               mod_timer(...);
               goto refill;

perhaps?

David