[PATCH v2 2/8] vdpa/ifc: add multi queue support

[Pei, Andy]

Hi Chenbo,

Thanks for your reply.
My reply is inline.

> -----Original Message-----
> From: Xia, Chenbo <chenbo.xia at intel.com>
> Sent: Friday, September 9, 2022 8:29 AM
> To: Pei, Andy <andy.pei at intel.com>; dev at dpdk.org
> Cc: Xu, Rosen <rosen.xu at intel.com>; Huang, Wei <wei.huang at intel.com>; Cao,
> Gang <gang.cao at intel.com>; maxime.coquelin at redhat.com; Huang Wei
> <wei_huang at intel.com>
> Subject: RE: [PATCH v2 2/8] vdpa/ifc: add multi queue support
> 
> > -----Original Message-----
> > From: Pei, Andy <andy.pei at intel.com>
> > Sent: Thursday, September 8, 2022 1:54 PM
> > To: dev at dpdk.org
> > Cc: Xia, Chenbo <chenbo.xia at intel.com>; Xu, Rosen
> > <rosen.xu at intel.com>; Huang, Wei <wei.huang at intel.com>; Cao, Gang
> > <gang.cao at intel.com>; maxime.coquelin at redhat.com; Huang Wei
> > <wei_huang at intel.com>
> > Subject: [PATCH v2 2/8] vdpa/ifc: add multi queue support
> 
> multi-queue
> 
Sure.
> >
> > Enable VHOST_USER_PROTOCOL_F_MQ feature.
> > ExposeIFCVF_MQ_OFFSET register to enable multi queue.
> 
> Please rephase it in a better way, at least add a space before
> IFCVF_MP_OFFSET...
> 
I will make it "Expose IFCVF_MQ_OFFSET register to enable multi queue."
> >
> > Signed-off-by: Andy Pei <andy.pei at intel.com>
> > Signed-off-by: Huang Wei <wei_huang at intel.com>
> > ---
> >  drivers/vdpa/ifc/base/ifcvf.c | 5 +++++
> > drivers/vdpa/ifc/base/ifcvf.h | 2 ++  drivers/vdpa/ifc/ifcvf_vdpa.c |
> > 1 +
> >  3 files changed, 8 insertions(+)
> >
> > diff --git a/drivers/vdpa/ifc/base/ifcvf.c
> > b/drivers/vdpa/ifc/base/ifcvf.c index f1e1474..34c8226 100644
> > --- a/drivers/vdpa/ifc/base/ifcvf.c
> > +++ b/drivers/vdpa/ifc/base/ifcvf.c
> > @@ -90,6 +90,11 @@
> >  	if (!hw->lm_cfg)
> >  		WARNINGOUT("HW support live migration not support!\n");
> >
> > +	if (hw->mem_resource[4].addr)
> > +		hw->mq_cfg = hw->mem_resource[4].addr +
> IFCVF_MQ_OFFSET;
> > +	else
> > +		hw->mq_cfg = NULL;
> 
> Could you help me understand the logic here? There are two cases that BAR 4
> mmap-able and not mmap-able?
> 
For some hardware implementation, for example the BAR 4 of PF is NULL, while BAR 4 of VF is not.
This code makes sure hw->mq_cfg is a valid address.

I am planning a optimization to check parameter consistent at init phase.
For example, if hardware does not support HW-assist live migration, we cannot use parameter like "sw-live-migration=0".

> Thanks,
> Chenbo
> 
> > +
> >  	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
> >  			hw->isr == NULL || hw->dev_cfg == NULL) {
> >  		DEBUGOUT("capability incomplete\n"); diff --git
> > a/drivers/vdpa/ifc/base/ifcvf.h b/drivers/vdpa/ifc/base/ifcvf.h index
> > 7ede738..ad505f1 100644
> > --- a/drivers/vdpa/ifc/base/ifcvf.h
> > +++ b/drivers/vdpa/ifc/base/ifcvf.h
> > @@ -50,6 +50,7 @@
> >
> >  #define IFCVF_LM_CFG_SIZE		0x40
> >  #define IFCVF_LM_RING_STATE_OFFSET	0x20
> > +#define IFCVF_MQ_OFFSET			0x28
> >
> >  #define IFCVF_LM_LOGGING_CTRL		0x0
> >
> > @@ -149,6 +150,7 @@ struct ifcvf_hw {
> >  	u16    *notify_base;
> >  	u16    *notify_addr[IFCVF_MAX_QUEUES * 2];
> >  	u8     *lm_cfg;
> > +	u8     *mq_cfg;
> >  	struct vring_info vring[IFCVF_MAX_QUEUES * 2];
> >  	u8 nr_vring;
> >  	int device_type;
> > diff --git a/drivers/vdpa/ifc/ifcvf_vdpa.c
> > b/drivers/vdpa/ifc/ifcvf_vdpa.c index 61d0250..2d165c0 100644
> > --- a/drivers/vdpa/ifc/ifcvf_vdpa.c
> > +++ b/drivers/vdpa/ifc/ifcvf_vdpa.c
> > @@ -1248,6 +1248,7 @@ struct rte_vdpa_dev_info {
> >  		 1ULL << VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD | \
> >  		 1ULL << VHOST_USER_PROTOCOL_F_HOST_NOTIFIER | \
> >  		 1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD | \
> > +		 1ULL << VHOST_USER_PROTOCOL_F_MQ | \
> >  		 1ULL << VHOST_USER_PROTOCOL_F_STATUS)
> >
> >  #define VDPA_BLK_PROTOCOL_FEATURES \
> > --
> > 1.8.3.1