Re: [PATCH net-next v3 1/9] xen-netback: Introduce TX grant map definitions

[Roger Pau Monné]

On 09/01/14 16:30, Wei Liu wrote:
> On Wed, Jan 08, 2014 at 12:10:10AM +0000, Zoltan Kiss wrote:
>> This patch contains the new definitions necessary for grant mapping.
>>
>> v2:
>> - move unmapping to separate thread. The NAPI instance has to be scheduled
>>   even from thread context, which can cause huge delays
>> - that causes unfortunately bigger struct xenvif
>> - store grant handle after checking validity
>>
>> v3:
>> - fix comment in xenvif_tx_dealloc_action()
>> - call unmap hypercall directly instead of gnttab_unmap_refs(), which does
>>   unnecessary m2p_override. Also remove pages_to_[un]map members
> 
> Is it worthy to have another function call
> gnttab_unmap_refs_no_m2p_override in Xen core driver, or just add a
> parameter to control wether we need to touch m2p_override? I *think* it
> will benefit block driver as well?

Anthony Liguori posted a patch to perform something similar in blkback,
but I think the patch never made it upstream:

https://lkml.org/lkml/2013/11/12/749

Probably a good time to revisit it so this mechanism can be used by both
blkback and netback?

Roger.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/