On 1/29/20 11:09 AM, Matan Azrad wrote:
> As an arrangement to the vitrio queues creation, a 2 QPs and CQ may be
> created for the virtio queue.
>
> The design is to trigger an event for the guest and for the vdpa driver
> when a new CQE is posted by the HW after the packet transition.
>
> This patch add the basic operations to create and destroy the above HW
> objects and to trigger the CQE events when a new CQE is posted.
>
> Signed-off-by: Matan Azrad <ma...@mellanox.com>
> Acked-by: Viacheslav Ovsiienko <viachesl...@mellanox.com>
> ---
> drivers/common/mlx5/mlx5_prm.h | 4 +
> drivers/vdpa/mlx5/Makefile | 1 +
> drivers/vdpa/mlx5/meson.build | 1 +
> drivers/vdpa/mlx5/mlx5_vdpa.h | 89 ++++++++
> drivers/vdpa/mlx5/mlx5_vdpa_event.c | 399
> ++++++++++++++++++++++++++++++++++++
> 5 files changed, 494 insertions(+)
> create mode 100644 drivers/vdpa/mlx5/mlx5_vdpa_event.c
>
> diff --git a/drivers/common/mlx5/mlx5_prm.h b/drivers/common/mlx5/mlx5_prm.h
> index b48cd0a..b533798 100644
> --- a/drivers/common/mlx5/mlx5_prm.h
> +++ b/drivers/common/mlx5/mlx5_prm.h
> @@ -392,6 +392,10 @@ struct mlx5_cqe {
> /* CQE format value. */
> #define MLX5_COMPRESSED 0x3
>
> +/* CQ doorbell cmd types. */
> +#define MLX5_CQ_DBR_CMD_SOL_ONLY (1 << 24)
> +#define MLX5_CQ_DBR_CMD_ALL (0 << 24)
> +
> /* Action type of header modification. */
> enum {
> MLX5_MODIFICATION_TYPE_SET = 0x1,
> diff --git a/drivers/vdpa/mlx5/Makefile b/drivers/vdpa/mlx5/Makefile
> index 5472797..7f13756 100644
> --- a/drivers/vdpa/mlx5/Makefile
> +++ b/drivers/vdpa/mlx5/Makefile
> @@ -9,6 +9,7 @@ LIB = librte_pmd_mlx5_vdpa.a
> # Sources.
> SRCS-$(CONFIG_RTE_LIBRTE_MLX5_VDPA_PMD) += mlx5_vdpa.c
> SRCS-$(CONFIG_RTE_LIBRTE_MLX5_VDPA_PMD) += mlx5_vdpa_mem.c
> +SRCS-$(CONFIG_RTE_LIBRTE_MLX5_VDPA_PMD) += mlx5_vdpa_event.c
>
> # Basic CFLAGS.
> CFLAGS += -O3
> diff --git a/drivers/vdpa/mlx5/meson.build b/drivers/vdpa/mlx5/meson.build
> index 7e5dd95..c609f7c 100644
> --- a/drivers/vdpa/mlx5/meson.build
> +++ b/drivers/vdpa/mlx5/meson.build
> @@ -13,6 +13,7 @@ deps += ['hash', 'common_mlx5', 'vhost', 'bus_pci', 'eal',
> 'sched']
> sources = files(
> 'mlx5_vdpa.c',
> 'mlx5_vdpa_mem.c',
> + 'mlx5_vdpa_event.c',
> )
> cflags_options = [
> '-std=c11',
> diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.h b/drivers/vdpa/mlx5/mlx5_vdpa.h
> index e27baea..30030b7 100644
> --- a/drivers/vdpa/mlx5/mlx5_vdpa.h
> +++ b/drivers/vdpa/mlx5/mlx5_vdpa.h
> @@ -9,9 +9,40 @@
>
> #include <rte_vdpa.h>
> #include <rte_vhost.h>
> +#include <rte_spinlock.h>
> +#include <rte_interrupts.h>
>
> #include <mlx5_glue.h>
> #include <mlx5_devx_cmds.h>
> +#include <mlx5_prm.h>
> +
> +
> +#define MLX5_VDPA_INTR_RETRIES 256
> +#define MLX5_VDPA_INTR_RETRIES_USEC 1000
> +
> +struct mlx5_vdpa_cq {
> + uint16_t log_desc_n;
> + uint32_t cq_ci:24;
> + uint32_t arm_sn:2;
> + rte_spinlock_t sl;
> + struct mlx5_devx_obj *cq;
> + struct mlx5dv_devx_umem *umem_obj;
> + union {
> + volatile void *umem_buf;
> + volatile struct mlx5_cqe *cqes;
> + };
> + volatile uint32_t *db_rec;
> + uint64_t errors;
> +};
> +
> +struct mlx5_vdpa_event_qp {
> + struct mlx5_vdpa_cq cq;
> + struct mlx5_devx_obj *fw_qp;
> + struct mlx5_devx_obj *sw_qp;
> + struct mlx5dv_devx_umem *umem_obj;
> + void *umem_buf;
> + volatile uint32_t *db_rec;
> +};
>
> struct mlx5_vdpa_query_mr {
> SLIST_ENTRY(mlx5_vdpa_query_mr) next;
> @@ -34,6 +65,10 @@ struct mlx5_vdpa_priv {
> uint32_t gpa_mkey_index;
> struct ibv_mr *null_mr;
> struct rte_vhost_memory *vmem;
> + uint32_t eqn;
> + struct mlx5dv_devx_event_channel *eventc;
> + struct mlx5dv_devx_uar *uar;
> + struct rte_intr_handle intr_handle;
> SLIST_HEAD(mr_list, mlx5_vdpa_query_mr) mr_list;
> };
>
> @@ -57,4 +92,58 @@ struct mlx5_vdpa_priv {
> */
> int mlx5_vdpa_mem_register(struct mlx5_vdpa_priv *priv);
>
> +
> +/**
> + * Create an event QP and all its related resources.
> + *
> + * @param[in] priv
> + * The vdpa driver private structure.
> + * @param[in] desc_n
> + * Number of descriptors.
> + * @param[in] callfd
> + * The guest notification file descriptor.
> + * @param[in/out] eqp
> + * Pointer to the event QP structure.
> + *
> + * @return
> + * 0 on success, -1 otherwise and rte_errno is set.
> + */
> +int mlx5_vdpa_event_qp_create(struct mlx5_vdpa_priv *priv, uint16_t desc_n,
> + int callfd, struct mlx5_vdpa_event_qp *eqp);
> +
> +/**
> + * Destroy an event QP and all its related resources.
> + *
> + * @param[in/out] eqp
> + * Pointer to the event QP structure.
> + */
> +void mlx5_vdpa_event_qp_destroy(struct mlx5_vdpa_event_qp *eqp);
> +
> +/**
> + * Release all the event global resources.
> + *
> + * @param[in] priv
> + * The vdpa driver private structure.
> + */
> +void mlx5_vdpa_event_qp_global_release(struct mlx5_vdpa_priv *priv);
> +
> +/**
> + * Setup CQE event.
> + *
> + * @param[in] priv
> + * The vdpa driver private structure.
> + *
> + * @return
> + * 0 on success, a negative errno value otherwise and rte_errno is set.
> + */
> +int mlx5_vdpa_cqe_event_setup(struct mlx5_vdpa_priv *priv);
> +
> +/**
> + * Unset CQE event .
> + *
> + * @param[in] priv
> + * The vdpa driver private structure.
> + */
> +void mlx5_vdpa_cqe_event_unset(struct mlx5_vdpa_priv *priv);
> +
> #endif /* RTE_PMD_MLX5_VDPA_H_ */
> diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_event.c
> b/drivers/vdpa/mlx5/mlx5_vdpa_event.c
> new file mode 100644
> index 0000000..35518ad
> --- /dev/null
> +++ b/drivers/vdpa/mlx5/mlx5_vdpa_event.c
> @@ -0,0 +1,399 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2019 Mellanox Technologies, Ltd
> + */
> +#include <unistd.h>
> +#include <stdint.h>
> +#include <fcntl.h>
> +
> +#include <rte_malloc.h>
> +#include <rte_errno.h>
> +#include <rte_lcore.h>
> +#include <rte_atomic.h>
> +#include <rte_common.h>
> +#include <rte_io.h>
> +
> +#include <mlx5_common.h>
> +
> +#include "mlx5_vdpa_utils.h"
> +#include "mlx5_vdpa.h"
> +
> +
> +void
> +mlx5_vdpa_event_qp_global_release(struct mlx5_vdpa_priv *priv)
> +{
> + if (priv->uar) {
> + mlx5_glue->devx_free_uar(priv->uar);
> + priv->uar = NULL;
> + }
> + if (priv->eventc) {
> + mlx5_glue->devx_destroy_event_channel(priv->eventc);
> + priv->eventc = NULL;
> + }
> + priv->eqn = 0;
> +}
> +
> +/* Prepare all the global resources for all the event objects.*/
> +static int
> +mlx5_vdpa_event_qp_global_prepare(struct mlx5_vdpa_priv *priv)
> +{
> + uint32_t lcore;
> +
> + if (priv->eventc)
> + return 0;
> + lcore = (uint32_t)rte_lcore_to_cpu_id(-1);
> + if (mlx5_glue->devx_query_eqn(priv->ctx, lcore, &priv->eqn)) {
> + rte_errno = errno;
> + DRV_LOG(ERR, "Failed to query EQ number %d.", rte_errno);
> + return -1;
> + }
> + priv->eventc = mlx5_glue->devx_create_event_channel(priv->ctx,
> + MLX5DV_DEVX_CREATE_EVENT_CHANNEL_FLAGS_OMIT_EV_DATA);
> + if (!priv->eventc) {
> + rte_errno = errno;
> + DRV_LOG(ERR, "Failed to create event channel %d.",
> + rte_errno);
> + goto error;
> + }
> + priv->uar = mlx5_glue->devx_alloc_uar(priv->ctx, 0);
> + if (!priv->uar) {
> + rte_errno = errno;
> + DRV_LOG(ERR, "Failed to allocate UAR.");
> + goto error;
> + }
> + return 0;
> +error:
> + mlx5_vdpa_event_qp_global_release(priv);
> + return -1;
> +}
> +
> +static void
> +mlx5_vdpa_cq_destroy(struct mlx5_vdpa_cq *cq)
> +{
> + if (cq->cq)
> + claim_zero(mlx5_devx_cmd_destroy(cq->cq));
> + if (cq->umem_obj)
> + claim_zero(mlx5_glue->devx_umem_dereg(cq->umem_obj));
> + if (cq->umem_buf)
> + rte_free((void *)(uintptr_t)cq->umem_buf);
> + memset(cq, 0, sizeof(*cq));
> +}
> +
> +static inline void
> +mlx5_vdpa_cq_arm(struct mlx5_vdpa_priv *priv, struct mlx5_vdpa_cq *cq)
> +{
> + const unsigned int cqe_mask = (1 << cq->log_desc_n) - 1;
> + uint32_t arm_sn = cq->arm_sn << MLX5_CQ_SQN_OFFSET;
> + uint32_t cq_ci = cq->cq_ci & MLX5_CI_MASK & cqe_mask;
> + uint32_t doorbell_hi = arm_sn | MLX5_CQ_DBR_CMD_ALL | cq_ci;
> + uint64_t doorbell = ((uint64_t)doorbell_hi << 32) | cq->cq->id;
> + uint64_t db_be = rte_cpu_to_be_64(doorbell);
> + uint32_t *addr = RTE_PTR_ADD(priv->uar->base_addr, MLX5_CQ_DOORBELL);
> +
> + rte_io_wmb();
> + cq->db_rec[MLX5_CQ_ARM_DB] = rte_cpu_to_be_32(doorbell_hi);
> + rte_wmb();
> +#ifdef RTE_ARCH_64
> + *(uint64_t *)addr = db_be;
> +#else
> + *(uint32_t *)addr = db_be;
> + rte_io_wmb();
> + *((uint32_t *)addr + 1) = db_be >> 32;
> +#endif
> + cq->arm_sn++;
> +}
> +
> +static int
> +mlx5_vdpa_cq_create(struct mlx5_vdpa_priv *priv, uint16_t log_desc_n,
> + int callfd, struct mlx5_vdpa_cq *cq)
> +{
> + struct mlx5_devx_cq_attr attr;
> + size_t pgsize = sysconf(_SC_PAGESIZE);
> + uint32_t umem_size;
> + int ret;
> + uint16_t event_nums[1] = {0};
> +
> + cq->log_desc_n = log_desc_n;
> + umem_size = sizeof(struct mlx5_cqe) * (1 << log_desc_n) +
> + sizeof(*cq->db_rec) * 2;
> + cq->umem_buf = rte_zmalloc(__func__, umem_size, 4096);
> + if (!cq->umem_buf) {
> + DRV_LOG(ERR, "Failed to allocate memory for CQ.");
> + rte_errno = ENOMEM;
> + return -ENOMEM;
> + }
> + cq->umem_obj = mlx5_glue->devx_umem_reg(priv->ctx,
> + (void *)(uintptr_t)cq->umem_buf,
> + umem_size,
> + IBV_ACCESS_LOCAL_WRITE);
> + if (!cq->umem_obj) {
> + DRV_LOG(ERR, "Failed to register umem for CQ.");
> + goto error;
> + }
> + attr.q_umem_valid = 1;
> + attr.db_umem_valid = 1;
> + attr.use_first_only = 0;
> + attr.overrun_ignore = 0;
> + attr.uar_page_id = priv->uar->page_id;
> + attr.q_umem_id = cq->umem_obj->umem_id;
> + attr.q_umem_offset = 0;
> + attr.db_umem_id = cq->umem_obj->umem_id;
> + attr.db_umem_offset = sizeof(struct mlx5_cqe) * (1 << log_desc_n);
> + attr.eqn = priv->eqn;
> + attr.log_cq_size = log_desc_n;
> + attr.log_page_size = rte_log2_u32(pgsize);
> + cq->cq = mlx5_devx_cmd_create_cq(priv->ctx, &attr);
> + if (!cq->cq)
> + goto error;
> + cq->db_rec = RTE_PTR_ADD(cq->umem_buf, (uintptr_t)attr.db_umem_offset);
> + cq->cq_ci = 0;
> + rte_spinlock_init(&cq->sl);
> + /* Subscribe CQ event to the event channel controlled by the driver. */
> + ret = mlx5_glue->devx_subscribe_devx_event(priv->eventc, cq->cq->obj,
> + sizeof(event_nums),
> + event_nums,
> + (uint64_t)(uintptr_t)cq);
> + if (ret) {
> + DRV_LOG(ERR, "Failed to subscribe CQE event.");
> + rte_errno = errno;
> + goto error;
> + }
> + /* Subscribe CQ event to the guest FD only if it is not in poll mode. */
> + 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;
> + }
> + }
> + /* First arming. */
> + mlx5_vdpa_cq_arm(priv, cq);
> + return 0;
> +error:
> + mlx5_vdpa_cq_destroy(cq);
> + return -1;
> +}
> +
> +static inline void __rte_unused
> +mlx5_vdpa_cq_poll(struct mlx5_vdpa_priv *priv __rte_unused,
> + struct mlx5_vdpa_cq *cq)
> +{
> + struct mlx5_vdpa_event_qp *eqp =
> + container_of(cq, struct mlx5_vdpa_event_qp, cq);
> + const unsigned int cqe_size = 1 << cq->log_desc_n;
> + const unsigned int cqe_mask = cqe_size - 1;
> + int ret;
> +
> + do {
> + volatile struct mlx5_cqe *cqe = cq->cqes + (cq->cq_ci &
> + cqe_mask);
> +
> + ret = check_cqe(cqe, cqe_size, cq->cq_ci);
> + switch (ret) {
> + case MLX5_CQE_STATUS_ERR:
> + cq->errors++;
> + /*fall-through*/
> + case MLX5_CQE_STATUS_SW_OWN:
> + cq->cq_ci++;
> + break;
> + case MLX5_CQE_STATUS_HW_OWN:
> + default:
> + break;
> + }
> + } while (ret != MLX5_CQE_STATUS_HW_OWN);
Isn't there a risk of endless loop here?
> + rte_io_wmb();
> + /* 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 + cqe_size);
> +}
> +