#define wmb() rte_wmb()
#define rmb() rte_rmb()
+#ifdef RTE_PMD_PACKET_PREFETCH
+#define rte_packet_prefetch(p) rte_prefetch1(p)
+#else
+#define rte_packet_prefetch(p) do {} while(0)
+#endif
+
#define VIRTQUEUE_MAX_NAME_SZ 32
#define RTE_MBUF_DATA_DMA_ADDR(mb) \
* VQ_RING_DESC_CHAIN_END.
*/
uint16_t vq_desc_head_idx;
+ uint16_t vq_desc_tail_idx;
/**
* Last consumed descriptor in the used table,
* trails vq_ring.used->idx.
*/
uint16_t vq_used_cons_idx;
+ uint16_t vq_avail_idx;
void *virtio_net_hdr_mem; /**< hdr for each xmit packet */
struct vq_desc_extra {
#define VIRTQUEUE_NUSED(vq) ((uint16_t)((vq)->vq_ring.used->idx - (vq)->vq_used_cons_idx))
static inline void
-vq_ring_update_avail(struct virtqueue *vq, uint16_t desc_idx)
+vq_update_avail_idx(struct virtqueue *vq)
+{
+ rte_compiler_barrier();
+ vq->vq_ring.avail->idx = vq->vq_avail_idx;
+}
+
+static inline void
+vq_update_avail_ring(struct virtqueue *vq, uint16_t desc_idx)
{
uint16_t avail_idx;
/*
* Place the head of the descriptor chain into the next slot and make
- * it usable to the host. The chain is made available now rather than
- * deferring to virtqueue_notify() in the hopes that if the host is
- * currently running on another CPU, we can keep it processing the new
- * descriptor.
+ * it usable to the host. We wait to inform the host until after the burst
+ * is complete to avoid cache alignment issues with descriptors. This
+ * also helps to avoid any contention on the available index.
*/
- avail_idx = (uint16_t)(vq->vq_ring.avail->idx & (vq->vq_nentries - 1));
+ avail_idx = (uint16_t)(vq->vq_avail_idx & (vq->vq_nentries - 1));
vq->vq_ring.avail->ring[avail_idx] = desc_idx;
- mb();
- vq->vq_ring.avail->idx++;
+ vq->vq_avail_idx++;
}
static inline int virtqueue_kick_prepare(struct virtqueue * vq)
static inline void
vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx)
{
- struct vring_desc *dp;
+ struct vring_desc *dp, *dp_tail;
struct vq_desc_extra *dxp;
+ uint16_t desc_idx_last = desc_idx;
dp = &vq->vq_ring.desc[desc_idx];
dxp = &vq->vq_descx[desc_idx];
vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt + dxp->ndescs);
if ((dp->flags & VRING_DESC_F_INDIRECT) == 0) {
while (dp->flags & VRING_DESC_F_NEXT) {
+ desc_idx_last = dp->next;
dp = &vq->vq_ring.desc[dp->next];
}
}
* newly freed chain. If the virtqueue was completely used, then
* head would be VQ_RING_DESC_CHAIN_END (ASSERTed above).
*/
- dp->next = vq->vq_desc_head_idx;
- vq->vq_desc_head_idx = desc_idx;
+ if (vq->vq_desc_tail_idx == VQ_RING_DESC_CHAIN_END) {
+ vq->vq_desc_head_idx = desc_idx;
+ } else {
+ dp_tail = &vq->vq_ring.desc[vq->vq_desc_tail_idx];
+ dp_tail->next = desc_idx;
+ }
+ vq->vq_desc_tail_idx = desc_idx_last;
+ dp->next = VQ_RING_DESC_CHAIN_END;
}
static inline int
start_dp[idx].flags = VRING_DESC_F_WRITE;
idx = start_dp[idx].next;
vq->vq_desc_head_idx = idx;
+ if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
+ vq->vq_desc_tail_idx = idx;
vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed);
- vq_ring_update_avail(vq, head_idx);
+ vq_update_avail_ring(vq, head_idx);
return (0);
}
idx = head_idx;
dxp = &txvq->vq_descx[idx];
+ if (dxp->cookie != NULL)
+ rte_pktmbuf_free_seg(dxp->cookie);
dxp->cookie = (void *)cookie;
dxp->ndescs = needed;
start_dp[idx].flags = 0;
idx = start_dp[idx].next;
txvq->vq_desc_head_idx = idx;
+ if (txvq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END)
+ txvq->vq_desc_tail_idx = idx;
txvq->vq_free_cnt = (uint16_t)(txvq->vq_free_cnt - needed);
- vq_ring_update_avail(txvq, head_idx);
+ vq_update_avail_ring(txvq, head_idx);
return (0);
}
static inline uint16_t
-virtqueue_dequeue_burst(struct virtqueue *vq, struct rte_mbuf **rx_pkts, uint32_t *len, uint16_t num)
+virtqueue_dequeue_burst_rx(struct virtqueue *vq, struct rte_mbuf **rx_pkts, uint32_t *len, uint16_t num)
{
struct vring_used_elem *uep;
struct rte_mbuf *cookie;
uint16_t used_idx, desc_idx;
uint16_t i;
+
/* Caller does the check */
for (i = 0; i < num ; i ++) {
used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
uep = &vq->vq_ring.used->ring[used_idx];
desc_idx = (uint16_t) uep->id;
+ len[i] = uep->len;
cookie = (struct rte_mbuf *)vq->vq_descx[desc_idx].cookie;
if (unlikely(cookie == NULL)) {
PMD_DRV_LOG(ERR, "vring descriptor with no mbuf cookie at %u\n",
vq->vq_used_cons_idx);
break;
}
- len[i] = uep->len;
+ rte_prefetch0(cookie);
+ rte_packet_prefetch(cookie->pkt.data);
rx_pkts[i] = cookie;
vq->vq_used_cons_idx++;
vq_ring_free_chain(vq, desc_idx);
return (i);
}
+static inline uint16_t
+virtqueue_dequeue_pkt_tx(struct virtqueue *vq)
+{
+ struct vring_used_elem *uep;
+ uint16_t used_idx, desc_idx;
+
+ used_idx = (uint16_t)(vq->vq_used_cons_idx & (vq->vq_nentries - 1));
+ uep = &vq->vq_ring.used->ring[used_idx];
+ desc_idx = (uint16_t) uep->id;
+ vq->vq_used_cons_idx++;
+ vq_ring_free_chain(vq, desc_idx);
+
+ return 0;
+}
+
#ifdef RTE_LIBRTE_VIRTIO_DEBUG_DUMP
#define VIRTQUEUE_DUMP(vq) do { \
uint16_t used_idx, nused; \
git.droids-corp.org / dpdk.git / blobdiff