[PATCH v4 02/14] ring: create common structure for prod and cons metadata

[Bruce Richardson <bruce.richardson@intel.com>]

create a common structure to hold the metadata for the producer and
the consumer, since both need essentially the same information - the
head and tail values, the ring size and mask.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>
---
V3: removed union and replaced with "single" variable
V2: renamed the shared structure based on maintainer feedback.
---
 lib/librte_pdump/rte_pdump.c    |  2 +-
 lib/librte_port/rte_port_ring.c | 12 ++++++------
 lib/librte_ring/rte_ring.c      |  4 ++--
 lib/librte_ring/rte_ring.h      | 41 +++++++++++++++++++----------------------
 4 files changed, 28 insertions(+), 31 deletions(-)

diff --git a/lib/librte_pdump/rte_pdump.c b/lib/librte_pdump/rte_pdump.c
index a580a6a..cc0b5b1 100644
--- a/lib/librte_pdump/rte_pdump.c
+++ b/lib/librte_pdump/rte_pdump.c
@@ -740,7 +740,7 @@ pdump_validate_ring_mp(struct rte_ring *ring, struct rte_mempool *mp)
 		rte_errno = EINVAL;
 		return -1;
 	}
-	if (ring->prod.sp_enqueue || ring->cons.sc_dequeue) {
+	if (ring->prod.single || ring->cons.single) {
 		RTE_LOG(ERR, PDUMP, "ring with either SP or SC settings"
 		" is not valid for pdump, should have MP and MC settings\n");
 		rte_errno = EINVAL;
diff --git a/lib/librte_port/rte_port_ring.c b/lib/librte_port/rte_port_ring.c
index 3b9d3d0..0df1bcf 100644
--- a/lib/librte_port/rte_port_ring.c
+++ b/lib/librte_port/rte_port_ring.c
@@ -73,8 +73,8 @@ rte_port_ring_reader_create_internal(void *params, int socket_id,
 	/* Check input parameters */
 	if ((conf == NULL) ||
 		(conf->ring == NULL) ||
-		(conf->ring->cons.sc_dequeue && is_multi) ||
-		(!(conf->ring->cons.sc_dequeue) && !is_multi)) {
+		(conf->ring->cons.single && is_multi) ||
+		(!(conf->ring->cons.single) && !is_multi)) {
 		RTE_LOG(ERR, PORT, "%s: Invalid Parameters\n", __func__);
 		return NULL;
 	}
@@ -198,8 +198,8 @@ rte_port_ring_writer_create_internal(void *params, int socket_id,
 	/* Check input parameters */
 	if ((conf == NULL) ||
 		(conf->ring == NULL) ||
-		(conf->ring->prod.sp_enqueue && is_multi) ||
-		(!(conf->ring->prod.sp_enqueue) && !is_multi) ||
+		(conf->ring->prod.single && is_multi) ||
+		(!(conf->ring->prod.single) && !is_multi) ||
 		(conf->tx_burst_sz > RTE_PORT_IN_BURST_SIZE_MAX)) {
 		RTE_LOG(ERR, PORT, "%s: Invalid Parameters\n", __func__);
 		return NULL;
@@ -467,8 +467,8 @@ rte_port_ring_writer_nodrop_create_internal(void *params, int socket_id,
 	/* Check input parameters */
 	if ((conf == NULL) ||
 		(conf->ring == NULL) ||
-		(conf->ring->prod.sp_enqueue && is_multi) ||
-		(!(conf->ring->prod.sp_enqueue) && !is_multi) ||
+		(conf->ring->prod.single && is_multi) ||
+		(!(conf->ring->prod.single) && !is_multi) ||
 		(conf->tx_burst_sz > RTE_PORT_IN_BURST_SIZE_MAX)) {
 		RTE_LOG(ERR, PORT, "%s: Invalid Parameters\n", __func__);
 		return NULL;
diff --git a/lib/librte_ring/rte_ring.c b/lib/librte_ring/rte_ring.c
index 4bc6da1..93a8692 100644
--- a/lib/librte_ring/rte_ring.c
+++ b/lib/librte_ring/rte_ring.c
@@ -145,8 +145,8 @@ rte_ring_init(struct rte_ring *r, const char *name, unsigned count,
 		return -ENAMETOOLONG;
 	r->flags = flags;
 	r->prod.watermark = count;
-	r->prod.sp_enqueue = !!(flags & RING_F_SP_ENQ);
-	r->cons.sc_dequeue = !!(flags & RING_F_SC_DEQ);
+	r->prod.single = !!(flags & RING_F_SP_ENQ);
+	r->cons.single = !!(flags & RING_F_SC_DEQ);
 	r->prod.size = r->cons.size = count;
 	r->prod.mask = r->cons.mask = count-1;
 	r->prod.head = r->cons.head = 0;
diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h
index 399ae3b..331c94f 100644
--- a/lib/librte_ring/rte_ring.h
+++ b/lib/librte_ring/rte_ring.h
@@ -1,7 +1,7 @@
 /*-
  *   BSD LICENSE
  *
- *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *   Copyright(c) 2010-2017 Intel Corporation. All rights reserved.
  *   All rights reserved.
  *
  *   Redistribution and use in source and binary forms, with or without
@@ -147,6 +147,16 @@ struct rte_memzone; /* forward declaration, so as not to require memzone.h */
 #define CONS_ALIGN RTE_CACHE_LINE_SIZE
 #endif
 
+/* structure to hold a pair of head/tail values and other metadata */
+struct rte_ring_headtail {
+	volatile uint32_t head;  /**< Prod/consumer head. */
+	volatile uint32_t tail;  /**< Prod/consumer tail. */
+	uint32_t size;           /**< Size of ring. */
+	uint32_t mask;           /**< Mask (size-1) of ring. */
+	uint32_t single;         /**< True if single prod/cons */
+	uint32_t watermark;      /**< Max items before EDQUOT in producer. */
+};
+
 /**
  * An RTE ring structure.
  *
@@ -169,23 +179,10 @@ struct rte_ring {
 			/**< Memzone, if any, containing the rte_ring */
 
 	/** Ring producer status. */
-	struct prod {
-		uint32_t watermark;      /**< Maximum items before EDQUOT. */
-		uint32_t sp_enqueue;     /**< True, if single producer. */
-		uint32_t size;           /**< Size of ring. */
-		uint32_t mask;           /**< Mask (size-1) of ring. */
-		volatile uint32_t head;  /**< Producer head. */
-		volatile uint32_t tail;  /**< Producer tail. */
-	} prod __rte_aligned(PROD_ALIGN);
+	struct rte_ring_headtail prod __rte_aligned(PROD_ALIGN);
 
 	/** Ring consumer status. */
-	struct cons {
-		uint32_t sc_dequeue;     /**< True, if single consumer. */
-		uint32_t size;           /**< Size of the ring. */
-		uint32_t mask;           /**< Mask (size-1) of ring. */
-		volatile uint32_t head;  /**< Consumer head. */
-		volatile uint32_t tail;  /**< Consumer tail. */
-	} cons __rte_aligned(CONS_ALIGN);
+	struct rte_ring_headtail cons __rte_aligned(CONS_ALIGN);
 
 #ifdef RTE_LIBRTE_RING_DEBUG
 	struct rte_ring_debug_stats stats[RTE_MAX_LCORE];
@@ -837,7 +834,7 @@ static inline int __attribute__((always_inline))
 rte_ring_enqueue_bulk(struct rte_ring *r, void * const *obj_table,
 		      unsigned n)
 {
-	if (r->prod.sp_enqueue)
+	if (r->prod.single)
 		return rte_ring_sp_enqueue_bulk(r, obj_table, n);
 	else
 		return rte_ring_mp_enqueue_bulk(r, obj_table, n);
@@ -904,7 +901,7 @@ rte_ring_sp_enqueue(struct rte_ring *r, void *obj)
 static inline int __attribute__((always_inline))
 rte_ring_enqueue(struct rte_ring *r, void *obj)
 {
-	if (r->prod.sp_enqueue)
+	if (r->prod.single)
 		return rte_ring_sp_enqueue(r, obj);
 	else
 		return rte_ring_mp_enqueue(r, obj);
@@ -975,7 +972,7 @@ rte_ring_sc_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n)
 static inline int __attribute__((always_inline))
 rte_ring_dequeue_bulk(struct rte_ring *r, void **obj_table, unsigned n)
 {
-	if (r->cons.sc_dequeue)
+	if (r->cons.single)
 		return rte_ring_sc_dequeue_bulk(r, obj_table, n);
 	else
 		return rte_ring_mc_dequeue_bulk(r, obj_table, n);
@@ -1039,7 +1036,7 @@ rte_ring_sc_dequeue(struct rte_ring *r, void **obj_p)
 static inline int __attribute__((always_inline))
 rte_ring_dequeue(struct rte_ring *r, void **obj_p)
 {
-	if (r->cons.sc_dequeue)
+	if (r->cons.single)
 		return rte_ring_sc_dequeue(r, obj_p);
 	else
 		return rte_ring_mc_dequeue(r, obj_p);
@@ -1206,7 +1203,7 @@ static inline unsigned __attribute__((always_inline))
 rte_ring_enqueue_burst(struct rte_ring *r, void * const *obj_table,
 		      unsigned n)
 {
-	if (r->prod.sp_enqueue)
+	if (r->prod.single)
 		return rte_ring_sp_enqueue_burst(r, obj_table, n);
 	else
 		return rte_ring_mp_enqueue_burst(r, obj_table, n);
@@ -1274,7 +1271,7 @@ rte_ring_sc_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n)
 static inline unsigned __attribute__((always_inline))
 rte_ring_dequeue_burst(struct rte_ring *r, void **obj_table, unsigned n)
 {
-	if (r->cons.sc_dequeue)
+	if (r->cons.single)
 		return rte_ring_sc_dequeue_burst(r, obj_table, n);
 	else
 		return rte_ring_mc_dequeue_burst(r, obj_table, n);
-- 
2.9.3