Re: [dpdk-dev] [PATCH v1] net/i40e: support request any number of queues

["Yan, Zhirun" <zhirun.yan@intel.com>]

> -----Original Message-----
> From: Kevin Traynor [mailto:ktraynor@redhat.com]
> Sent: Wednesday, January 16, 2019 1:34 AM
> To: Yan, Zhirun <zhirun.yan@intel.com>; dev@dpdk.org; Zhang, Qi Z
> <qi.z.zhang@intel.com>
> Subject: Re: [dpdk-dev] [PATCH v1] net/i40e: support request any number of
> queues
> 
> On 01/15/2019 02:57 PM, Zhirun Yan wrote:
> > Before this patch, VF must request a specific queues(1/2/4/8/16) with
> > DPDK PF. This patch align the number of requested queues to next power
> > of 2. So VF can request any number queues from 1 to 16.
> >
> > Signed-off-by: Zhirun Yan <zhirun.yan@intel.com>
> > ---
> >  drivers/net/i40e/i40e_pf.c | 5 ++++-
> >  1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/i40e/i40e_pf.c b/drivers/net/i40e/i40e_pf.c
> > index 092e0d3e9..d110dffb7 100644
> > --- a/drivers/net/i40e/i40e_pf.c
> > +++ b/drivers/net/i40e/i40e_pf.c
> > @@ -1271,7 +1271,10 @@
> i40e_pf_host_process_cmd_request_queues(struct i40e_pf_vf *vf, uint8_t
> *msg)
> >  	} else {
> >  		i40e_vc_notify_vf_reset(vf);
> >  		vf->vsi->nb_qps = req_pairs;
> > -		pf->vf_nb_qps = req_pairs;
> > +		if (rte_is_power_of_2(req_pairs))
> > +			pf->vf_nb_qps = req_pairs;
> > +		else
> > +			pf->vf_nb_qps = i40e_align_floor(req_pairs) << 1;
> 
> Shouldn't you do this before you validate against the number of free queue
> pairs? or it is somehow handled

Before PF alloc queue to VF, PF will check the queue number in i40e_res_pool_alloc().
Suppose there are 15 queues left in PF, this part will check 12 as a valid value if request 12 queues,
 But PF  will refuse to alloc 16 queue.

> 
> >  		i40e_pf_host_process_cmd_reset_vf(vf);
> >
> >  		return 0;
> >