From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Vrabel <david.vrabel@citrix.com>
Subject: Re: netback grant copying issues
Date: Mon, 7 Sep 2015 16:11:42 +0100
Message-ID: <55EDA92E.2070701@citrix.com>
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To: Jan Beulich <JBeulich@suse.com>, Wei Liu <wei.liu2@citrix.com>, Ian
	Campbell <Ian.Campbell@eu.citrix.com>
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On 04/09/15 10:27, Jan Beulich wrote:
> Ian, Wei,
> 
> I seem to be seeing two issues in the grant copy handling of netback,
> solely from code inspection:
> 
> 1) Shouldn't MAX_GRANT_COPY_OPS, to take care of the copying
> the header may require, be
> ((MAX_SKB_FRAGS + 1) * XEN_NETIF_RX_RING_SIZE)?

We really should have the copy batches be independent of ring size and
skb format.

e.g., Call xenvif_gnt_copy_add(ref, ptr, len) for each copy op needed.
This will issue the hypercall when the batch is full.  There would need
to be axenvif_gnt_copy_flush() at the end for last hypercall for the
remaining ops.

David