X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=lib%2Flibrte_ring%2Frte_ring.h;h=e359affc5b8da775ac1567b741c50d9ee0040179;hb=e961cf425e021ca0dcbd781098647720d05b0c60;hp=943c97cf4a8c664b93d925bd11808c94ceac34b6;hpb=693f715da45c48ec1ec0fe4ba2f3b5ffd11ba53e;p=dpdk.git

diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h
index 943c97cf4a..e359affc5b 100644
--- a/lib/librte_ring/rte_ring.h
+++ b/lib/librte_ring/rte_ring.h
@@ -100,12 +100,13 @@ extern "C" {
 #include <rte_lcore.h>
 #include <rte_atomic.h>
 #include <rte_branch_prediction.h>
+#include <rte_memzone.h>
 
 #define RTE_TAILQ_RING_NAME "RTE_RING"
 
 enum rte_ring_queue_behavior {
 	RTE_RING_QUEUE_FIXED = 0, /* Enq/Deq a fixed number of items from a ring */
-	RTE_RING_QUEUE_VARIABLE   /* Enq/Deq as many items a possible from ring */
+	RTE_RING_QUEUE_VARIABLE   /* Enq/Deq as many items as possible from ring */
 };
 
 #ifdef RTE_LIBRTE_RING_DEBUG
@@ -126,8 +127,10 @@ struct rte_ring_debug_stats {
 } __rte_cache_aligned;
 #endif
 
-#define RTE_RING_NAMESIZE 32 /**< The maximum length of a ring name. */
 #define RTE_RING_MZ_PREFIX "RG_"
+/**< The maximum length of a ring name. */
+#define RTE_RING_NAMESIZE (RTE_MEMZONE_NAMESIZE - \
+			   sizeof(RTE_RING_MZ_PREFIX) + 1)
 
 #ifndef RTE_RING_PAUSE_REP_COUNT
 #define RTE_RING_PAUSE_REP_COUNT 0 /**< Yield after pause num of times, no yield
@@ -147,7 +150,12 @@ struct rte_memzone; /* forward declaration, so as not to require memzone.h */
  * a problem.
  */
 struct rte_ring {
-	char name[RTE_RING_NAMESIZE];    /**< Name of the ring. */
+	/*
+	 * Note: this field kept the RTE_MEMZONE_NAMESIZE size due to ABI
+	 * compatibility requirements, it could be changed to RTE_RING_NAMESIZE
+	 * next time the ABI changes
+	 */
+	char name[RTE_MEMZONE_NAMESIZE];    /**< Name of the ring. */
 	int flags;                       /**< Flags supplied at creation. */
 	const struct rte_memzone *memzone;
 			/**< Memzone, if any, containing the rte_ring */
@@ -179,7 +187,7 @@ struct rte_ring {
 	struct rte_ring_debug_stats stats[RTE_MAX_LCORE];
 #endif
 
-	void * ring[0] __rte_cache_aligned; /**< Memory space of ring starts here.
+	void *ring[] __rte_cache_aligned;   /**< Memory space of ring starts here.
 	                                     * not volatile so need to be careful
 	                                     * about compiler re-ordering */
 };
@@ -333,7 +341,7 @@ void rte_ring_free(struct rte_ring *r);
 int rte_ring_set_water_mark(struct rte_ring *r, unsigned count);
 
 /**
- * Dump the status of the ring to the console.
+ * Dump the status of the ring to a file.
  *
  * @param f
  *   A pointer to a file for output
@@ -431,6 +439,11 @@ __rte_ring_mp_do_enqueue(struct rte_ring *r, void * const *obj_table,
 	uint32_t mask = r->prod.mask;
 	int ret;
 
+	/* Avoid the unnecessary cmpset operation below, which is also
+	 * potentially harmful when n equals 0. */
+	if (n == 0)
+		return 0;
+
 	/* move prod.head atomically */
 	do {
 		/* Reset n to the initial burst count */
@@ -618,6 +631,11 @@ __rte_ring_mc_do_dequeue(struct rte_ring *r, void **obj_table,
 	unsigned i, rep = 0;
 	uint32_t mask = r->prod.mask;
 
+	/* Avoid the unnecessary cmpset operation below, which is also
+	 * potentially harmful when n equals 0. */
+	if (n == 0)
+		return 0;
+
 	/* move cons.head atomically */
 	do {
 		/* Restore n as it may change every loop */