[RFC] regexdev: add maximum number of mbuf segments field

[RFC] regexdev: add maximum number of mbuf segments field

[Gerry Gribbon]

Allows application to query maximum number of mbuf segments that can
be chained together.

Signed-off-by: Gerry Gribbon <ggribbon@nvidia.com>
---
 drivers/regex/mlx5/mlx5_regex.h          |  1 +
 drivers/regex/mlx5/mlx5_regex_fastpath.c | 43 ++++++++++++++++++++++++
 drivers/regex/mlx5/mlx5_rxp.c            |  1 +
 lib/regexdev/rte_regexdev.h              |  2 ++
 4 files changed, 47 insertions(+)

diff --git a/drivers/regex/mlx5/mlx5_regex.h b/drivers/regex/mlx5/mlx5_regex.h
index 89495301ac..98fe95b781 100644
--- a/drivers/regex/mlx5/mlx5_regex.h
+++ b/drivers/regex/mlx5/mlx5_regex.h
@@ -94,4 +94,5 @@ uint16_t mlx5_regexdev_dequeue(struct rte_regexdev *dev, uint16_t qp_id,
 		       struct rte_regex_ops **ops, uint16_t nb_ops);
 uint16_t mlx5_regexdev_enqueue_gga(struct rte_regexdev *dev, uint16_t qp_id,
 		       struct rte_regex_ops **ops, uint16_t nb_ops);
+uint16_t mlx5_regexdev_max_segs_get(void);
 #endif /* MLX5_REGEX_H */
diff --git a/drivers/regex/mlx5/mlx5_regex_fastpath.c b/drivers/regex/mlx5/mlx5_regex_fastpath.c
index 9a2db7e43f..16f48627e5 100644
--- a/drivers/regex/mlx5/mlx5_regex_fastpath.c
+++ b/drivers/regex/mlx5/mlx5_regex_fastpath.c
@@ -41,6 +41,39 @@
 /* In WQE set mode, the pi should be quarter of the MLX5_REGEX_MAX_WQE_INDEX. */
 #define MLX5_REGEX_UMR_QP_PI_IDX(pi, ops) \
 	(((pi) + (ops)) & (MLX5_REGEX_MAX_WQE_INDEX >> 2))
+#ifdef RTE_LIBRTE_MLX5_DEBUG
+#define MLX5_REGEX_DEBUG 0
+#endif
+#ifdef HAVE_MLX5_UMR_IMKEY
+static uint16_t max_nb_segs = MLX5_REGEX_MAX_KLM_NUM;
+#else
+static uint16_t max_nb_segs = 1;
+#endif
+
+uint16_t
+mlx5_regexdev_max_segs_get(void)
+{
+	return max_nb_segs;
+}
+
+#ifdef MLX5_REGEX_DEBUG
+static inline uint16_t
+validate_ops(struct rte_regex_ops **ops, uint16_t nb_ops)
+{
+	uint16_t nb_left = nb_ops;
+	struct rte_mbuf *mbuf;
+
+	while (nb_left--) {
+		mbuf = ops[nb_left]->mbuf;
+		if ((mbuf->pkt_len > MLX5_RXP_MAX_JOB_LENGTH) ||
+		    (mbuf->nb_segs > max_nb_segs)) {
+			DRV_LOG(ERR, "Failed to validate regex ops");
+			return 1;
+		}
+	}
+	return 0;
+}
+#endif
 
 static inline uint32_t
 qp_size_get(struct mlx5_regex_hw_qp *qp)
@@ -375,6 +408,11 @@ mlx5_regexdev_enqueue_gga(struct rte_regexdev *dev, uint16_t qp_id,
 	struct mlx5_regex_hw_qp *qp_obj;
 	size_t hw_qpid, nb_left = nb_ops, nb_desc;
 
+#ifdef MLX5_REGEX_DEBUG
+	if (validate_ops(ops, nb_ops))
+		return 0;
+#endif
+
 	while ((hw_qpid = ffs(queue->free_qps))) {
 		hw_qpid--; /* ffs returns 1 for bit 0 */
 		qp_obj = &queue->qps[hw_qpid];
@@ -409,6 +447,11 @@ mlx5_regexdev_enqueue(struct rte_regexdev *dev, uint16_t qp_id,
 	struct mlx5_regex_hw_qp *qp_obj;
 	size_t hw_qpid, job_id, i = 0;
 
+#ifdef MLX5_REGEX_DEBUG
+	if (validate_ops(ops, nb_ops))
+		return 0;
+#endif
+
 	while ((hw_qpid = ffs(queue->free_qps))) {
 		hw_qpid--; /* ffs returns 1 for bit 0 */
 		qp_obj = &queue->qps[hw_qpid];
diff --git a/drivers/regex/mlx5/mlx5_rxp.c b/drivers/regex/mlx5/mlx5_rxp.c
index ed3af15e40..35a4cfb7ac 100644
--- a/drivers/regex/mlx5/mlx5_rxp.c
+++ b/drivers/regex/mlx5/mlx5_rxp.c
@@ -45,6 +45,7 @@ mlx5_regex_info_get(struct rte_regexdev *dev __rte_unused,
 			      RTE_REGEXDEV_CAPA_QUEUE_PAIR_OOS_F;
 	info->rule_flags = 0;
 	info->max_queue_pairs = UINT16_MAX;
+	info->max_num_mbuf_segs = mlx5_regexdev_max_segs_get();
 	return 0;
 }
 
diff --git a/lib/regexdev/rte_regexdev.h b/lib/regexdev/rte_regexdev.h
index 3bce8090f6..7d2e1ee1d0 100644
--- a/lib/regexdev/rte_regexdev.h
+++ b/lib/regexdev/rte_regexdev.h
@@ -622,6 +622,8 @@ struct rte_regexdev_info {
 	/**< Supported compiler rule flags.
 	 * @see RTE_REGEX_PCRE_RULE_*, struct rte_regexdev_rule::rule_flags
 	 */
+	uint16_t max_num_mbuf_segs;
+	/**< Maximum number of mbuf segments that can be chained together. */
 };
 
 /**
-- 
2.25.1

Re: [RFC] regexdev: add maximum number of mbuf segments field

[Stephen Hemminger]

On Tue, 26 Jul 2022 10:47:07 +0000
Gerry Gribbon <ggribbon@nvidia.com> wrote:

> diff --git a/lib/regexdev/rte_regexdev.h b/lib/regexdev/rte_regexdev.h
> index 3bce8090f6..7d2e1ee1d0 100644
> --- a/lib/regexdev/rte_regexdev.h
> +++ b/lib/regexdev/rte_regexdev.h
> @@ -622,6 +622,8 @@ struct rte_regexdev_info {
>  	/**< Supported compiler rule flags.
>  	 * @see RTE_REGEX_PCRE_RULE_*, struct rte_regexdev_rule::rule_flags
>  	 */
> +	uint16_t max_num_mbuf_segs;
> +	/**< Maximum number of mbuf segments that can be chained together. */
>  };
>  
>  /**

Did you notice that that struct is sparse and there is already
an existing hole that could be reused.  This is going to be an API/ABI
breakage already so reusing the hole will be ok.

Also, please update the release notes for this.