vdpa/mlx5: optimize notification events
[dpdk.git] / drivers / vdpa / mlx5 / mlx5_vdpa_event.c
index dd60150..743e52a 100644 (file)
@@ -12,6 +12,7 @@
 #include <rte_atomic.h>
 #include <rte_common.h>
 #include <rte_io.h>
+#include <rte_alarm.h>
 
 #include <mlx5_common.h>
 
@@ -19,6 +20,9 @@
 #include "mlx5_vdpa.h"
 
 
+#define MLX5_VDPA_DEFAULT_TIMER_DELAY_US 500u
+#define MLX5_VDPA_NO_TRAFFIC_TIME_S 2LLU
+
 void
 mlx5_vdpa_event_qp_global_release(struct mlx5_vdpa_priv *priv)
 {
@@ -26,10 +30,23 @@ mlx5_vdpa_event_qp_global_release(struct mlx5_vdpa_priv *priv)
                mlx5_glue->devx_free_uar(priv->uar);
                priv->uar = NULL;
        }
+#ifdef HAVE_IBV_DEVX_EVENT
        if (priv->eventc) {
+               union {
+                       struct mlx5dv_devx_async_event_hdr event_resp;
+                       uint8_t buf[sizeof(struct mlx5dv_devx_async_event_hdr)
+                                                                        + 128];
+               } out;
+
+               /* Clean all pending events. */
+               while (mlx5_glue->devx_get_event(priv->eventc, &out.event_resp,
+                      sizeof(out.buf)) >=
+                      (ssize_t)sizeof(out.event_resp.cookie))
+                       ;
                mlx5_glue->devx_destroy_event_channel(priv->eventc);
                priv->eventc = NULL;
        }
+#endif
        priv->eqn = 0;
 }
 
@@ -79,7 +96,7 @@ mlx5_vdpa_cq_destroy(struct mlx5_vdpa_cq *cq)
        memset(cq, 0, sizeof(*cq));
 }
 
-static inline void
+static inline void __rte_unused
 mlx5_vdpa_cq_arm(struct mlx5_vdpa_priv *priv, struct mlx5_vdpa_cq *cq)
 {
        uint32_t arm_sn = cq->arm_sn << MLX5_CQ_SQN_OFFSET;
@@ -100,6 +117,7 @@ mlx5_vdpa_cq_arm(struct mlx5_vdpa_priv *priv, struct mlx5_vdpa_cq *cq)
        *((uint32_t *)addr + 1) = db_be >> 32;
 #endif
        cq->arm_sn++;
+       cq->armed = 1;
 }
 
 static int
@@ -157,6 +175,16 @@ mlx5_vdpa_cq_create(struct mlx5_vdpa_priv *priv, uint16_t log_desc_n,
                rte_errno = errno;
                goto error;
        }
+       if (callfd != -1) {
+               ret = mlx5_glue->devx_subscribe_devx_event_fd(priv->eventc,
+                                                             callfd,
+                                                             cq->cq->obj, 0);
+               if (ret) {
+                       DRV_LOG(ERR, "Failed to subscribe CQE event fd.");
+                       rte_errno = errno;
+                       goto error;
+               }
+       }
        cq->callfd = callfd;
        /* Init CQ to ones to be in HW owner in the start. */
        memset((void *)(uintptr_t)cq->umem_buf, 0xFF, attr.db_umem_offset);
@@ -168,27 +196,27 @@ error:
        return -1;
 }
 
-static inline void __rte_unused
-mlx5_vdpa_cq_poll(struct mlx5_vdpa_priv *priv __rte_unused,
-                 struct mlx5_vdpa_cq *cq)
+static inline uint32_t
+mlx5_vdpa_cq_poll(struct mlx5_vdpa_cq *cq)
 {
        struct mlx5_vdpa_event_qp *eqp =
                                container_of(cq, struct mlx5_vdpa_event_qp, cq);
        const unsigned int cq_size = 1 << cq->log_desc_n;
        const unsigned int cq_mask = cq_size - 1;
+       uint32_t total = 0;
        int ret;
 
        do {
-               volatile struct mlx5_cqe *cqe = cq->cqes + (cq->cq_ci &
-                                                           cq_mask);
+               volatile struct mlx5_cqe *cqe = cq->cqes + ((cq->cq_ci + total)
+                                                           cq_mask);
 
-               ret = check_cqe(cqe, cq_size, cq->cq_ci);
+               ret = check_cqe(cqe, cq_size, cq->cq_ci + total);
                switch (ret) {
                case MLX5_CQE_STATUS_ERR:
                        cq->errors++;
                        /*fall-through*/
                case MLX5_CQE_STATUS_SW_OWN:
-                       cq->cq_ci++;
+                       total++;
                        break;
                case MLX5_CQE_STATUS_HW_OWN:
                default:
@@ -196,21 +224,86 @@ mlx5_vdpa_cq_poll(struct mlx5_vdpa_priv *priv __rte_unused,
                }
        } while (ret != MLX5_CQE_STATUS_HW_OWN);
        rte_io_wmb();
+       cq->cq_ci += total;
        /* Ring CQ doorbell record. */
        cq->db_rec[0] = rte_cpu_to_be_32(cq->cq_ci);
        rte_io_wmb();
        /* Ring SW QP doorbell record. */
        eqp->db_rec[0] = rte_cpu_to_be_32(cq->cq_ci + cq_size);
+       return total;
+}
+
+static void
+mlx5_vdpa_arm_all_cqs(struct mlx5_vdpa_priv *priv)
+{
+       struct mlx5_vdpa_cq *cq;
+       int i;
+
+       for (i = 0; i < priv->nr_virtqs; i++) {
+               cq = &priv->virtqs[i].eqp.cq;
+               if (cq->cq && !cq->armed)
+                       mlx5_vdpa_cq_arm(priv, cq);
+       }
+}
+
+static void *
+mlx5_vdpa_poll_handle(void *arg)
+{
+       struct mlx5_vdpa_priv *priv = arg;
+       int i;
+       struct mlx5_vdpa_cq *cq;
+       uint32_t total;
+       uint64_t current_tic;
+
+       pthread_mutex_lock(&priv->timer_lock);
+       while (!priv->timer_on)
+               pthread_cond_wait(&priv->timer_cond, &priv->timer_lock);
+       pthread_mutex_unlock(&priv->timer_lock);
+       while (1) {
+               total = 0;
+               for (i = 0; i < priv->nr_virtqs; i++) {
+                       cq = &priv->virtqs[i].eqp.cq;
+                       if (cq->cq && !cq->armed) {
+                               uint32_t comp = mlx5_vdpa_cq_poll(cq);
+
+                               if (comp) {
+                                       /* Notify guest for descs consuming. */
+                                       if (cq->callfd != -1)
+                                               eventfd_write(cq->callfd,
+                                                             (eventfd_t)1);
+                                       total += comp;
+                               }
+                       }
+               }
+               current_tic = rte_rdtsc();
+               if (!total) {
+                       /* No traffic ? stop timer and load interrupts. */
+                       if (current_tic - priv->last_traffic_tic >=
+                           rte_get_timer_hz() * MLX5_VDPA_NO_TRAFFIC_TIME_S) {
+                               DRV_LOG(DEBUG, "Device %s traffic was stopped.",
+                                       priv->vdev->device->name);
+                               mlx5_vdpa_arm_all_cqs(priv);
+                               pthread_mutex_lock(&priv->timer_lock);
+                               priv->timer_on = 0;
+                               while (!priv->timer_on)
+                                       pthread_cond_wait(&priv->timer_cond,
+                                                         &priv->timer_lock);
+                               pthread_mutex_unlock(&priv->timer_lock);
+                               continue;
+                       }
+               } else {
+                       priv->last_traffic_tic = current_tic;
+               }
+               usleep(priv->timer_delay_us);
+       }
+       return NULL;
 }
 
 static void
 mlx5_vdpa_interrupt_handler(void *cb_arg)
 {
-#ifndef HAVE_IBV_DEVX_EVENT
-       (void)cb_arg;
-       return;
-#else
        struct mlx5_vdpa_priv *priv = cb_arg;
+#ifdef HAVE_IBV_DEVX_EVENT
        union {
                struct mlx5dv_devx_async_event_hdr event_resp;
                uint8_t buf[sizeof(struct mlx5dv_devx_async_event_hdr) + 128];
@@ -221,17 +314,30 @@ mlx5_vdpa_interrupt_handler(void *cb_arg)
                                       (ssize_t)sizeof(out.event_resp.cookie)) {
                struct mlx5_vdpa_cq *cq = (struct mlx5_vdpa_cq *)
                                               (uintptr_t)out.event_resp.cookie;
-               rte_spinlock_lock(&cq->sl);
-               mlx5_vdpa_cq_poll(priv, cq);
-               mlx5_vdpa_cq_arm(priv, cq);
-               if (cq->callfd != -1)
-                       /* Notify guest for descriptors consuming. */
-                       eventfd_write(cq->callfd, (eventfd_t)1);
-               rte_spinlock_unlock(&cq->sl);
-               DRV_LOG(DEBUG, "CQ %d event: new cq_ci = %u.", cq->cq->id,
-                       cq->cq_ci);
+               struct mlx5_vdpa_event_qp *eqp = container_of(cq,
+                                                struct mlx5_vdpa_event_qp, cq);
+               struct mlx5_vdpa_virtq *virtq = container_of(eqp,
+                                                  struct mlx5_vdpa_virtq, eqp);
+
+               mlx5_vdpa_cq_poll(cq);
+               /* Don't arm again - timer will take control. */
+               DRV_LOG(DEBUG, "Device %s virtq %d cq %d event was captured."
+                       " Timer is %s, cq ci is %u.\n",
+                       priv->vdev->device->name,
+                       (int)virtq->index, cq->cq->id,
+                       priv->timer_on ? "on" : "off", cq->cq_ci);
+               cq->armed = 0;
+       }
+#endif
+
+       /* Traffic detected: make sure timer is on. */
+       priv->last_traffic_tic = rte_rdtsc();
+       pthread_mutex_lock(&priv->timer_lock);
+       if (!priv->timer_on) {
+               priv->timer_on = 1;
+               pthread_cond_signal(&priv->timer_cond);
        }
-#endif /* HAVE_IBV_DEVX_ASYNC */
+       pthread_mutex_unlock(&priv->timer_lock);
 }
 
 int
@@ -243,12 +349,21 @@ mlx5_vdpa_cqe_event_setup(struct mlx5_vdpa_priv *priv)
        if (!priv->eventc)
                /* All virtqs are in poll mode. */
                return 0;
+       pthread_mutex_init(&priv->timer_lock, NULL);
+       pthread_cond_init(&priv->timer_cond, NULL);
+       priv->timer_on = 0;
+       priv->timer_delay_us = MLX5_VDPA_DEFAULT_TIMER_DELAY_US;
+       ret = pthread_create(&priv->timer_tid, NULL, mlx5_vdpa_poll_handle,
+                            (void *)priv);
+       if (ret) {
+               DRV_LOG(ERR, "Failed to create timer thread.");
+               return -1;
+       }
        flags = fcntl(priv->eventc->fd, F_GETFL);
        ret = fcntl(priv->eventc->fd, F_SETFL, flags | O_NONBLOCK);
        if (ret) {
                DRV_LOG(ERR, "Failed to change event channel FD.");
-               rte_errno = errno;
-               return -rte_errno;
+               goto error;
        }
        priv->intr_handle.fd = priv->eventc->fd;
        priv->intr_handle.type = RTE_INTR_HANDLE_EXT;
@@ -256,9 +371,12 @@ mlx5_vdpa_cqe_event_setup(struct mlx5_vdpa_priv *priv)
                                       mlx5_vdpa_interrupt_handler, priv)) {
                priv->intr_handle.fd = 0;
                DRV_LOG(ERR, "Failed to register CQE interrupt %d.", rte_errno);
-               return -rte_errno;
+               goto error;
        }
        return 0;
+error:
+       mlx5_vdpa_cqe_event_unset(priv);
+       return -1;
 }
 
 void
@@ -266,6 +384,7 @@ mlx5_vdpa_cqe_event_unset(struct mlx5_vdpa_priv *priv)
 {
        int retries = MLX5_VDPA_INTR_RETRIES;
        int ret = -EAGAIN;
+       void *status;
 
        if (priv->intr_handle.fd) {
                while (retries-- && ret == -EAGAIN) {
@@ -276,11 +395,16 @@ mlx5_vdpa_cqe_event_unset(struct mlx5_vdpa_priv *priv)
                                DRV_LOG(DEBUG, "Try again to unregister fd %d "
                                        "of CQ interrupt, retries = %d.",
                                        priv->intr_handle.fd, retries);
-                               usleep(MLX5_VDPA_INTR_RETRIES_USEC);
+                               rte_pause();
                        }
                }
                memset(&priv->intr_handle, 0, sizeof(priv->intr_handle));
        }
+       if (priv->timer_tid) {
+               pthread_cancel(priv->timer_tid);
+               pthread_join(priv->timer_tid, &status);
+       }
+       priv->timer_tid = 0;
 }
 
 void