d/numam-dpdk
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

net/virtio: allocate fake mbuf in Rx queue

Browse Source 
While it is worth clarifying whether the fake mbuf
in virtnet_rx struct is really necessary, it is sure
that it heavily impacts cache usage by being part of
the struct. Indeed, it uses two cachelines, and
requires alignment on a cacheline.

Before this series, it means it took 120 bytes in
virtnet_rx struct:

struct virtnet_rx {
 struct virtqueue *vq; /*0 8*/

 /* XXX 56 bytes hole, try to pack */

 /* --- cacheline 1 boundary (64 bytes) --- */
 struct rte_mbuf fake_mbuf __attribute__((__aligned__(64))); /*64 128*/
 /* --- cacheline 3 boundary (192 bytes) --- */

This patch allocates it using malloc in order to optimize
virtnet_rx cache usage and so virtqueue cache usage.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>
Tested-by: Balazs Nemeth <bnemeth@redhat.com>
This commit is contained in:
Maxime Coquelin 2021-03-16 10:38:24 +01:00 committed by Chenbo Xia
parent 76fd789cc7
commit b59d4d5502
3 changed files with 17 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/net/virtio/virtio_ethdev.c
View File

@ -435,6 +435,7 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t queue_idx)
int queue_type = virtio_get_queue_type(hw, queue_idx);
int ret;
int numa_node = dev->device->numa_node;
struct rte_mbuf *fake_mbuf = NULL;
PMD_INIT_LOG(INFO, "setting up queue: %u on NUMA node %d",
queue_idx, numa_node);
@ -550,10 +551,19 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t queue_idx)
goto free_hdr_mz;
}
fake_mbuf = rte_zmalloc_socket("sw_ring", sizeof(*fake_mbuf),
RTE_CACHE_LINE_SIZE, numa_node);
if (!fake_mbuf) {
PMD_INIT_LOG(ERR, "can not allocate fake mbuf");
ret = -ENOMEM;
goto free_sw_ring;
}
vq->sw_ring = sw_ring;
rxvq = &vq->rxq;
rxvq->port_id = dev->data->port_id;
rxvq->mz = mz;
rxvq->fake_mbuf = fake_mbuf;
} else if (queue_type == VTNET_TQ) {
txvq = &vq->txq;
txvq->port_id = dev->data->port_id;
@ -612,6 +622,8 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t queue_idx)
clean_vq:
hw->cvq = NULL;
rte_free(fake_mbuf);
free_sw_ring:
rte_free(sw_ring);
free_hdr_mz:
rte_memzone_free(hdr_mz);
@ -641,6 +653,7 @@ virtio_free_queues(struct virtio_hw *hw)
queue_type = virtio_get_queue_type(hw, i);
if (queue_type == VTNET_RQ) {
rte_free(vq->rxq.fake_mbuf);
rte_free(vq->sw_ring);
rte_memzone_free(vq->rxq.mz);
} else if (queue_type == VTNET_TQ) {

9
drivers/net/virtio/virtio_rxtx.c
View File

@ -703,12 +703,9 @@ virtio_dev_rx_queue_setup_finish(struct rte_eth_dev *dev, uint16_t queue_idx)
virtio_rxq_vec_setup(rxvq);
}
memset(&rxvq->fake_mbuf, 0, sizeof(rxvq->fake_mbuf));
for (desc_idx = 0; desc_idx < RTE_PMD_VIRTIO_RX_MAX_BURST;
desc_idx++) {
vq->sw_ring[vq->vq_nentries + desc_idx] =
&rxvq->fake_mbuf;
}
memset(rxvq->fake_mbuf, 0, sizeof(*rxvq->fake_mbuf));
for (desc_idx = 0; desc_idx < RTE_PMD_VIRTIO_RX_MAX_BURST; desc_idx++)
vq->sw_ring[vq->vq_nentries + desc_idx] = rxvq->fake_mbuf;
if (hw->use_vec_rx && !virtio_with_packed_queue(hw)) {
while (vq->vq_free_cnt >= RTE_VIRTIO_VPMD_RX_REARM_THRESH) {

2
drivers/net/virtio/virtio_rxtx.h
View File

@ -19,7 +19,7 @@ struct virtnet_stats {
struct virtnet_rx {
/* dummy mbuf, for wraparound when processing RX ring. */
struct rte_mbuf fake_mbuf;
struct rte_mbuf *fake_mbuf;
uint64_t mbuf_initializer; /**< value to init mbufs. */
struct rte_mempool *mpool; /**< mempool for mbuf allocation */