Re: [PATCH] xen-blkback: allocate list of pending reqs in small chunks

["Roger Pau Monné" <roger.pau@citrix.com>]

On 29/04/13 20:37, Konrad Rzeszutek Wilk wrote:
> On Fri, Apr 26, 2013 at 03:47:40PM +0100, David Vrabel wrote:
>> On 26/04/13 14:45, Roger Pau Monne wrote:
>>> Allocate pending requests in smaller chunks instead of allocating them
>>> all at the same time.
>>>
>>> This change also removes the global array of pending_reqs, it is no
>>> longer necessay.
>>>
>>> Variables related to the grant mapping have been grouped into a struct
>>> called "grant_page", this allows to allocate them in smaller chunks,
>>> and also improves memory locality.
>>>
>> [...]
>>> diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
>>> index afab208..2841c0f 100644
>>> --- a/drivers/block/xen-blkback/xenbus.c
>>> +++ b/drivers/block/xen-blkback/xenbus.c
>>> @@ -127,22 +128,53 @@ static struct xen_blkif *xen_blkif_alloc(domid_t domid)
>>>         blkif->free_pages_num = 0;
>>>         atomic_set(&blkif->persistent_gnt_in_use, 0);
>>>
>>> -       blkif->pending_reqs = kcalloc(XEN_BLKIF_REQS,
>>> -                                     sizeof(blkif->pending_reqs[0]),
>>> -                                     GFP_KERNEL);
>>> -       if (!blkif->pending_reqs) {
>>> -               kmem_cache_free(xen_blkif_cachep, blkif);
>>> -               return ERR_PTR(-ENOMEM);
>>> -       }
>>>         INIT_LIST_HEAD(&blkif->pending_free);
>>> +
>>> +       pr_alert("sizeof req: %lu\n", sizeof(*req));
>>
>> Stray pr_alert() here.
>>
>> Looks good otherwise.
>>
>> Reviewed-by: David Vrabel <david.vrabel@citrix.com>
> 
> Roger, could you repost it please and also include Tested-by: Sander.. on it
> please?

Done, see v3.