[dpdk-dev] [PATCH v9 6/6] lib/eventdev: use custom element size ring for event rings

[Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>]

Use custom element size ring APIs to replace event ring
implementation. This avoids code duplication.

Signed-off-by: Honnappa Nagarahalli <honnappa.nagarahalli@arm.com>
Reviewed-by: Gavin Hu <gavin.hu@arm.com>
Reviewed-by: Ola Liljedahl <ola.liljedahl@arm.com>
---
 lib/librte_eventdev/rte_event_ring.c | 147 ++-------------------------
 lib/librte_eventdev/rte_event_ring.h |  45 ++++----
 2 files changed, 24 insertions(+), 168 deletions(-)

diff --git a/lib/librte_eventdev/rte_event_ring.c b/lib/librte_eventdev/rte_event_ring.c
index 50190de01..d27e23901 100644
--- a/lib/librte_eventdev/rte_event_ring.c
+++ b/lib/librte_eventdev/rte_event_ring.c
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: BSD-3-Clause
  * Copyright(c) 2017 Intel Corporation
+ * Copyright(c) 2019 Arm Limited
  */
 
 #include <sys/queue.h>
@@ -11,13 +12,6 @@
 #include <rte_eal_memconfig.h>
 #include "rte_event_ring.h"
 
-TAILQ_HEAD(rte_event_ring_list, rte_tailq_entry);
-
-static struct rte_tailq_elem rte_event_ring_tailq = {
-	.name = RTE_TAILQ_EVENT_RING_NAME,
-};
-EAL_REGISTER_TAILQ(rte_event_ring_tailq)
-
 int
 rte_event_ring_init(struct rte_event_ring *r, const char *name,
 	unsigned int count, unsigned int flags)
@@ -35,150 +29,21 @@ struct rte_event_ring *
 rte_event_ring_create(const char *name, unsigned int count, int socket_id,
 		unsigned int flags)
 {
-	char mz_name[RTE_MEMZONE_NAMESIZE];
-	struct rte_event_ring *r;
-	struct rte_tailq_entry *te;
-	const struct rte_memzone *mz;
-	ssize_t ring_size;
-	int mz_flags = 0;
-	struct rte_event_ring_list *ring_list = NULL;
-	const unsigned int requested_count = count;
-	int ret;
-
-	ring_list = RTE_TAILQ_CAST(rte_event_ring_tailq.head,
-		rte_event_ring_list);
-
-	/* for an exact size ring, round up from count to a power of two */
-	if (flags & RING_F_EXACT_SZ)
-		count = rte_align32pow2(count + 1);
-	else if (!rte_is_power_of_2(count)) {
-		rte_errno = EINVAL;
-		return NULL;
-	}
-
-	ring_size = sizeof(*r) + (count * sizeof(struct rte_event));
-
-	ret = snprintf(mz_name, sizeof(mz_name), "%s%s",
-		RTE_RING_MZ_PREFIX, name);
-	if (ret < 0 || ret >= (int)sizeof(mz_name)) {
-		rte_errno = ENAMETOOLONG;
-		return NULL;
-	}
-
-	te = rte_zmalloc("RING_TAILQ_ENTRY", sizeof(*te), 0);
-	if (te == NULL) {
-		RTE_LOG(ERR, RING, "Cannot reserve memory for tailq\n");
-		rte_errno = ENOMEM;
-		return NULL;
-	}
-
-	rte_mcfg_tailq_write_lock();
-
-	/*
-	 * reserve a memory zone for this ring. If we can't get rte_config or
-	 * we are secondary process, the memzone_reserve function will set
-	 * rte_errno for us appropriately - hence no check in this this function
-	 */
-	mz = rte_memzone_reserve(mz_name, ring_size, socket_id, mz_flags);
-	if (mz != NULL) {
-		r = mz->addr;
-		/* Check return value in case rte_ring_init() fails on size */
-		int err = rte_event_ring_init(r, name, requested_count, flags);
-		if (err) {
-			RTE_LOG(ERR, RING, "Ring init failed\n");
-			if (rte_memzone_free(mz) != 0)
-				RTE_LOG(ERR, RING, "Cannot free memzone\n");
-			rte_free(te);
-			rte_mcfg_tailq_write_unlock();
-			return NULL;
-		}
-
-		te->data = (void *) r;
-		r->r.memzone = mz;
-
-		TAILQ_INSERT_TAIL(ring_list, te, next);
-	} else {
-		r = NULL;
-		RTE_LOG(ERR, RING, "Cannot reserve memory\n");
-		rte_free(te);
-	}
-	rte_mcfg_tailq_write_unlock();
-
-	return r;
+	return (struct rte_event_ring *)rte_ring_create_elem(name,
+						sizeof(struct rte_event),
+						count, socket_id, flags);
 }
 
 
 struct rte_event_ring *
 rte_event_ring_lookup(const char *name)
 {
-	struct rte_tailq_entry *te;
-	struct rte_event_ring *r = NULL;
-	struct rte_event_ring_list *ring_list;
-
-	ring_list = RTE_TAILQ_CAST(rte_event_ring_tailq.head,
-			rte_event_ring_list);
-
-	rte_mcfg_tailq_read_lock();
-
-	TAILQ_FOREACH(te, ring_list, next) {
-		r = (struct rte_event_ring *) te->data;
-		if (strncmp(name, r->r.name, RTE_RING_NAMESIZE) == 0)
-			break;
-	}
-
-	rte_mcfg_tailq_read_unlock();
-
-	if (te == NULL) {
-		rte_errno = ENOENT;
-		return NULL;
-	}
-
-	return r;
+	return (struct rte_event_ring *)rte_ring_lookup(name);
 }
 
 /* free the ring */
 void
 rte_event_ring_free(struct rte_event_ring *r)
 {
-	struct rte_event_ring_list *ring_list = NULL;
-	struct rte_tailq_entry *te;
-
-	if (r == NULL)
-		return;
-
-	/*
-	 * Ring was not created with rte_event_ring_create,
-	 * therefore, there is no memzone to free.
-	 */
-	if (r->r.memzone == NULL) {
-		RTE_LOG(ERR, RING,
-			"Cannot free ring (not created with rte_event_ring_create()");
-		return;
-	}
-
-	if (rte_memzone_free(r->r.memzone) != 0) {
-		RTE_LOG(ERR, RING, "Cannot free memory\n");
-		return;
-	}
-
-	ring_list = RTE_TAILQ_CAST(rte_event_ring_tailq.head,
-			rte_event_ring_list);
-	rte_mcfg_tailq_write_lock();
-
-	/* find out tailq entry */
-	TAILQ_FOREACH(te, ring_list, next) {
-		if (te->data == (void *) r)
-			break;
-	}
-
-	if (te == NULL) {
-		rte_mcfg_tailq_write_unlock();
-		return;
-	}
-
-	TAILQ_REMOVE(ring_list, te, next);
-
-	rte_mcfg_tailq_write_unlock();
-
-	rte_free(te);
+	rte_ring_free((struct rte_ring *)r);
 }
diff --git a/lib/librte_eventdev/rte_event_ring.h b/lib/librte_eventdev/rte_event_ring.h
index 827a3209e..c0861b0ec 100644
--- a/lib/librte_eventdev/rte_event_ring.h
+++ b/lib/librte_eventdev/rte_event_ring.h
@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: BSD-3-Clause
  * Copyright(c) 2016-2017 Intel Corporation
+ * Copyright(c) 2019 Arm Limited
  */
 
 /**
@@ -19,6 +20,7 @@
 #include <rte_memory.h>
 #include <rte_malloc.h>
 #include <rte_ring.h>
+#include <rte_ring_elem.h>
 #include "rte_eventdev.h"
 
 #define RTE_TAILQ_EVENT_RING_NAME "RTE_EVENT_RING"
@@ -88,22 +90,17 @@ rte_event_ring_enqueue_burst(struct rte_event_ring *r,
 		const struct rte_event *events,
 		unsigned int n, uint16_t *free_space)
 {
-	uint32_t prod_head, prod_next;
-	uint32_t free_entries;
+	unsigned int num;
+	uint32_t space;
 
-	n = __rte_ring_move_prod_head(&r->r, r->r.prod.single, n,
-			RTE_RING_QUEUE_VARIABLE,
-			&prod_head, &prod_next, &free_entries);
-	if (n == 0)
-		goto end;
+	num = rte_ring_enqueue_burst_elem(&r->r, events,
+				sizeof(struct rte_event), n,
+				&space);
 
-	ENQUEUE_PTRS(&r->r, &r[1], prod_head, events, n, struct rte_event);
-
-	update_tail(&r->r.prod, prod_head, prod_next, r->r.prod.single, 1);
-end:
 	if (free_space != NULL)
-		*free_space = free_entries - n;
-	return n;
+		*free_space = space;
+
+	return num;
 }
 
 /**
@@ -129,23 +126,17 @@ rte_event_ring_dequeue_burst(struct rte_event_ring *r,
 		struct rte_event *events,
 		unsigned int n, uint16_t *available)
 {
-	uint32_t cons_head, cons_next;
-	uint32_t entries;
-
-	n = __rte_ring_move_cons_head(&r->r, r->r.cons.single, n,
-			RTE_RING_QUEUE_VARIABLE,
-			&cons_head, &cons_next, &entries);
-	if (n == 0)
-		goto end;
+	unsigned int num;
+	uint32_t remaining;
 
-	DEQUEUE_PTRS(&r->r, &r[1], cons_head, events, n, struct rte_event);
+	num = rte_ring_dequeue_burst_elem(&r->r, events,
+				sizeof(struct rte_event), n,
+				&remaining);
 
-	update_tail(&r->r.cons, cons_head, cons_next, r->r.cons.single, 0);
-
-end:
 	if (available != NULL)
-		*available = entries - n;
-	return n;
+		*available = remaining;
+
+	return num;
 }
 
 /*
-- 
2.17.1