Re: [dpdk-dev] [PATCH] virtio: split virtio rx/tx queue

[Yuanhan Liu <yuanhan.liu@linux.intel.com>]

On Mon, May 30, 2016 at 02:40:00AM +0000, Xie, Huawei wrote:
> On 5/27/2016 5:06 PM, Yuanhan Liu wrote:
> > On Tue, May 24, 2016 at 09:38:32PM +0800, Huawei Xie wrote:
> >>  	vq->vq_ring_mem = mz->phys_addr;
> >>  	vq->vq_ring_virt_mem = mz->addr;
> >> -	PMD_INIT_LOG(DEBUG, "vq->vq_ring_mem:      0x%"PRIx64, (uint64_t)mz->phys_addr);
> >> -	PMD_INIT_LOG(DEBUG, "vq->vq_ring_virt_mem: 0x%"PRIx64, (uint64_t)(uintptr_t)mz->addr);
> >> -	vq->virtio_net_hdr_mz  = NULL;
> >> -	vq->virtio_net_hdr_mem = 0;
> >> +	PMD_INIT_LOG(DEBUG, "vq->vq_ring_mem:      0x%"PRIx64,
> >> +		     (uint64_t)mz->phys_addr);
> >> +	PMD_INIT_LOG(DEBUG, "vq->vq_ring_virt_mem: 0x%"PRIx64,
> >> +		     (uint64_t)(uintptr_t)mz->addr);
> >> +
> >> +	hdr_mz = rte_memzone_reserve_aligned(vq_hdr_name, sz_hdr_mz, socket_id,
> >> +					     0, RTE_CACHE_LINE_SIZE);
> > We don't need allocate hdr_mz for Rx queue, and in such case, sz_hdr_mz
> > is 0. I'm wondering what hdr_mz would be then, NULL?
> >
> > Anyway, you should skip the hdr_mz allocation for Rx queue, and I also
> > would suggest you to move the vq_hdr_name setup here.
> 
> will check sz_hdr_mz before the zone allocation.
> 
> 
> >
> >> +	if (hdr_mz == NULL) {
> >> +		if (rte_errno == EEXIST)
> >> +			hdr_mz = rte_memzone_lookup(vq_hdr_name);
> >> +		if (hdr_mz == NULL) {
> >> +			ret = -ENOMEM;
> >> +			goto fail_q_alloc;
> >> +		}
> >> +	}
> >>  
> > ...
> >>  
> >>  	PMD_INIT_FUNC_TRACE();
> >>  	ret = virtio_dev_queue_setup(dev, VTNET_CQ, VTNET_SQ_CQ_QUEUE_IDX,
> >> -			vtpci_queue_idx, 0, socket_id, &vq);
> >> +			vtpci_queue_idx, 0, socket_id, (void **)&cvq);
> > Unnecessary cast. Note that there are few others like that in this
> > patch.
> 
> This cast is needed.

Oh, right, indeed. Sorry.

> >
> >> -		PMD_RX_LOG(DEBUG, "dequeue:%d", num);
> >> -		PMD_RX_LOG(DEBUG, "packet len:%d", len[0]);
> >> +		PMD_RX_LOG(DEBUG, "dequeue:%d\n", num);
> >> +		PMD_RX_LOG(DEBUG, "packet len:%d\n", len[0]);
> > We should not append "\n" for PMD_RX_LOG; this macro alreadys does it.
> 
> Weird. Will remove it. Thanks.
> 
> >
> > Another note is that you might want to run checkpatch; I saw quite many
> > warnings.
> 
> Had checked. The warnings are all due to 80 char limitation of
> virtio_rxq_stats_strings. Just 4 or 5 chars cross 80 line limit. I
> prefer to keep the fields aligned.

Agreed. However, I was talking about others warnings.

	--yliu

---
CHECK:BRACES: braces {} should be used on all arms of this statement
#198: FILE: drivers/net/virtio/virtio_ethdev.c:343:
+       if (queue_type == VTNET_RQ)
[...]
+       else if (queue_type == VTNET_TQ) {
[...]
+       } else if (queue_type == VTNET_CQ) {
[...]

CHECK:CAMELCASE: Avoid CamelCase: <PRIx64>
#280: FILE: drivers/net/virtio/virtio_ethdev.c:404:
+       PMD_INIT_LOG(DEBUG, "vq->vq_ring_mem:      0x%"PRIx64,

CHECK:CONCATENATED_STRING: Concatenated strings should use spaces
between elements
#280: FILE: drivers/net/virtio/virtio_ethdev.c:404:
+       PMD_INIT_LOG(DEBUG, "vq->vq_ring_mem:      0x%"PRIx64,

CHECK:CONCATENATED_STRING: Concatenated strings should use spaces
between elements
#282: FILE: drivers/net/virtio/virtio_ethdev.c:406:
+       PMD_INIT_LOG(DEBUG, "vq->vq_ring_virt_mem: 0x%"PRIx64,

WARNING:UNSPECIFIED_INT: Prefer 'unsigned int' to bare use of 'unsigned'
#482: FILE: drivers/net/virtio/virtio_ethdev.c:753:
+       unsigned nstats = dev->data->nb_tx_queues * VIRTIO_NB_TXQ_XSTATS
+

WARNING:LONG_LINE: line over 80 characters
#551: FILE: drivers/net/virtio/virtio_ethdev.c:819:
+               memset(txvq->stats.size_bins, 0,
sizeof(txvq->stats.size_bins[0]) * 8);

WARNING:LONG_LINE: line over 80 characters
#571: FILE: drivers/net/virtio/virtio_ethdev.c:832:
+               memset(rxvq->stats.size_bins, 0,
sizeof(rxvq->stats.size_bins[0]) * 8);

CHECK:MULTIPLE_ASSIGNMENTS: multiple assignments should be avoided
#1529: FILE: drivers/net/virtio/virtio_rxtx_simple.c:362:
+       nb_commit = nb_pkts = RTE_MIN((vq->vq_free_cnt >> 1), nb_pkts);

CHECK:SPACING: No space is necessary after a cast
#1530: FILE: drivers/net/virtio/virtio_rxtx_simple.c:363:
+       desc_idx = (uint16_t) (vq->vq_avail_idx & desc_idx_max);