On 19/03/2021 20:57, pbhagavatula@marvell.com wrote:

quoted

From: Pavan Nikhilesh <redacted>

Introduce rte_event_vector datastructure which is capable of holding
multiple uintptr_t of the same flow thereby allowing applications
to vectorize their pipeline and reducing the complexity of pipelining
the events across multiple stages.
This approach also reduces the scheduling overhead on a event

device.

quoted

Add a event vector mempool create handler to create mempools

based on

quoted

the best mempool ops available on a given platform.

Signed-off-by: Pavan Nikhilesh <redacted>
---
 doc/guides/prog_guide/eventdev.rst |  36 +++++++++-
 lib/librte_eventdev/rte_eventdev.h | 112

++++++++++++++++++++++++++++-

quoted

 lib/librte_eventdev/version.map    |   3 +
 3 files changed, 148 insertions(+), 3 deletions(-)

[SNIP]

quoted

diff --git a/lib/librte_eventdev/rte_eventdev.h

b/lib/librte_eventdev/rte_eventdev.h

quoted

index ce1fc2ce0..5586a3f15 100644

--- a/lib/librte_eventdev/rte_eventdev.h
+++ b/lib/librte_eventdev/rte_eventdev.h

@@ -212,8 +212,10 @@ extern "C" {

 #include <rte_common.h>
 #include <rte_config.h>
-#include <rte_memory.h>
 #include <rte_errno.h>
+#include <rte_mbuf_pool_ops.h>
+#include <rte_memory.h>
+#include <rte_mempool.h>

 #include "rte_eventdev_trace_fp.h"

@@ -913,6 +915,25 @@

rte_event_dev_stop_flush_callback_register(uint8_t dev_id,

quoted

 int
 rte_event_dev_close(uint8_t dev_id);

+/**
+ * Event vector structure.
+ */
+struct rte_event_vector {
+	uint64_t nb_elem : 16;
+	/**< Number of elements in this event vector. */
+	uint64_t rsvd : 48;
+	uint64_t impl_opaque;
+	union {
+		struct rte_mbuf *mbufs[0];
+		void *ptrs[0];
+		uint64_t *u64s[0];
+	} __rte_aligned(16);
+	/**< Start of the vector array union. Depending upon the event

type the

quoted

+	 * vector array can be an array of mbufs or pointers or opaque

u64

quoted

+	 * values.
+	 */
+};
+
 /* Scheduler type definitions */
 #define RTE_SCHED_TYPE_ORDERED          0
 /**< Ordered scheduling

@@ -986,6 +1007,21 @@ rte_event_dev_close(uint8_t dev_id);
  */
 #define RTE_EVENT_TYPE_ETH_RX_ADAPTER   0x4
 /**< The event generated from event eth Rx adapter */
+#define RTE_EVENT_TYPE_VECTOR           0x8
+/**< Indicates that event is a vector.
+ * All vector event types should be an logical OR of

EVENT_TYPE_VECTOR.

quoted

+ * This simplifies the pipeline design as we can split processing the

events

quoted

+ * between vector events and normal event across event types.
+ * Example:
+ *	if (ev.event_type & RTE_EVENT_TYPE_VECTOR) {
+ *		// Classify and handle vector event.
+ *	} else {
+ *		// Classify and handle event.
+ *	}
+ */
+#define RTE_EVENT_TYPE_CPU_VECTOR

(RTE_EVENT_TYPE_VECTOR | RTE_EVENT_TYPE_CPU)

quoted

+/**< The event vector generated from cpu for pipelining. */
+
 #define RTE_EVENT_TYPE_MAX              0x10
 /**< Maximum number of event types */

@@ -1108,6 +1144,8 @@ struct rte_event {
 		/**< Opaque event pointer */
 		struct rte_mbuf *mbuf;
 		/**< mbuf pointer if dequeued event is associated with

mbuf */

quoted

+		struct rte_event_vector *vec;
+		/**< Event vector pointer. */
 	};
 };

@@ -2023,6 +2061,78 @@ rte_event_dev_xstats_reset(uint8_t

dev_id,

quoted

  */
 int rte_event_dev_selftest(uint8_t dev_id);

+/**
+ * Get the memory required per event vector based on the number of

elements per

quoted

+ * vector.
+ * This should be used to create the mempool that holds the event

vectors.

quoted

+ *
+ * @param name
+ *   The name of the vector pool.
+ * @param n
+ *   The number of elements in the mbuf pool.
+ * @param cache_size
+ *   Size of the per-core object cache. See rte_mempool_create() for
+ *   details.
+ * @param nb_elem
+ *   The number of elements then a single event vector should be

able to hold.

quoted

+ * @param socket_id
+ *   The socket identifier where the memory should be allocated. The
+ *   value can be *SOCKET_ID_ANY* if there is no NUMA constraint

for the

quoted

+ *   reserved zone
+ *
+ * @return
+ *   The pointer to the newly allocated mempool, on success. NULL

on error

quoted

+ *   with rte_errno set appropriately. Possible rte_errno values

include:

quoted

+ *    - E_RTE_NO_CONFIG - function could not get pointer to

rte_config structure

quoted

+ *    - E_RTE_SECONDARY - function was called from a secondary

process instance

quoted

+ *    - EINVAL - cache size provided is too large, or priv_size is not

aligned.

quoted

+ *    - ENOSPC - the maximum number of memzones has already been

allocated

quoted

+ *    - EEXIST - a memzone with the same name already exists
+ *    - ENOMEM - no appropriate memory area found in which to

create memzone

quoted

+ */
+__rte_experimental
+static inline struct rte_mempool *
+rte_event_vector_pool_create(const char *name, unsigned int n,
+			     unsigned int cache_size, uint16_t nb_elem,
+			     int socket_id)

Handling in-lined function is tricky at best from an ABI stability PoV.

Since this function is used at initialization time and I would suggest since
performance is not issue here.
There is no need for this function to be an inline.

Makes sense, I will move it to .c in the next version.

Thanks, 
Pavan.

quoted

+{
+	const char *mp_ops_name;
+	struct rte_mempool *mp;
+	unsigned int elt_sz;
+	int ret;
+
+	if (!nb_elem) {
+		RTE_LOG(ERR, EVENTDEV,
+			"Invalid number of elements=%d requested\n",

nb_elem);

quoted

+		rte_errno = -EINVAL;
+		return NULL;
+	}
+
+	elt_sz =
+		sizeof(struct rte_event_vector) + (nb_elem *

sizeof(uintptr_t));

quoted

+	mp = rte_mempool_create_empty(name, n, elt_sz, cache_size,

0, socket_id,

quoted

+				      0);
+	if (mp == NULL)
+		return NULL;
+
+	mp_ops_name = rte_mbuf_best_mempool_ops();
+	ret = rte_mempool_set_ops_byname(mp, mp_ops_name,

NULL);

quoted

+	if (ret != 0) {
+		RTE_LOG(ERR, EVENTDEV, "error setting mempool

handler\n");

quoted

+		goto err;
+	}
+
+	ret = rte_mempool_populate_default(mp);
+	if (ret < 0)
+		goto err;
+
+	return mp;
+err:
+	rte_mempool_free(mp);
+	rte_errno = -ret;
+	return NULL;
+}
+
 #ifdef __cplusplus
 }
 #endif

diff --git a/lib/librte_eventdev/version.map

b/lib/librte_eventdev/version.map

quoted

index 3e5c09cfd..a070ef56e 100644

--- a/lib/librte_eventdev/version.map
+++ b/lib/librte_eventdev/version.map

@@ -138,6 +138,9 @@ EXPERIMENTAL {
 	__rte_eventdev_trace_port_setup;
 	# added in 20.11
 	rte_event_pmd_pci_probe_named;
+
+	#added in 21.05
+	rte_event_vector_pool_create;
 };

 INTERNAL {