[dpdk-dev] [PATCH 2/7] rte_ring: make ring tailq completely local

[Anatoly Burakov <anatoly.burakov@intel.com>]

---
 lib/librte_eal/linuxapp/eal/eal_ivshmem.c | 14 +++++++++++--
 lib/librte_ring/Makefile                  |  4 ++--
 lib/librte_ring/rte_ring.c                | 33 +++++++++++++++++++++++--------
 lib/librte_ring/rte_ring.h                |  2 --
 4 files changed, 39 insertions(+), 14 deletions(-)

diff --git a/lib/librte_eal/linuxapp/eal/eal_ivshmem.c b/lib/librte_eal/linuxapp/eal/eal_ivshmem.c
index 4ad76a7..69e5ea6 100644
--- a/lib/librte_eal/linuxapp/eal/eal_ivshmem.c
+++ b/lib/librte_eal/linuxapp/eal/eal_ivshmem.c
@@ -50,6 +50,7 @@
 #include <rte_errno.h>
 #include <rte_ring.h>
 #include <rte_mempool.h>
+#include <rte_malloc.h>
 #include <rte_common.h>
 #include <rte_ivshmem.h>
 #include <rte_tailq_elem.h>
@@ -101,7 +102,7 @@ static int memseg_idx;
 static int pagesz;
 
 /* Tailq heads to add rings to */
-TAILQ_HEAD(rte_ring_list, rte_ring);
+TAILQ_HEAD(rte_ring_list, rte_tailq_entry);
 
 /*
  * Utility functions
@@ -754,6 +755,7 @@ rte_eal_ivshmem_obj_init(void)
 	struct ivshmem_segment * seg;
 	struct rte_memzone * mz;
 	struct rte_ring * r;
+	struct rte_tailq_entry *te;
 	unsigned i, ms, idx;
 	uint64_t offset;
 
@@ -819,7 +821,15 @@ rte_eal_ivshmem_obj_init(void)
 
 		r = (struct rte_ring*) (mz->addr_64);
 
-		TAILQ_INSERT_TAIL(ring_list, r, next);
+		te = rte_zmalloc("RING_TAILQ_ENTRY", sizeof(*te), 0);
+		if (te == NULL) {
+			RTE_LOG(ERR, EAL, "Cannot allocate ring tailq entry!\n");
+			return -1;
+		}
+
+		te->data = (void *) r;
+
+		TAILQ_INSERT_TAIL(ring_list, te, next);
 
 		RTE_LOG(DEBUG, EAL, "Found ring: '%s' at %p\n", r->name, mz->addr);
 	}
diff --git a/lib/librte_ring/Makefile b/lib/librte_ring/Makefile
index 550507d..2380a43 100644
--- a/lib/librte_ring/Makefile
+++ b/lib/librte_ring/Makefile
@@ -42,7 +42,7 @@ SRCS-$(CONFIG_RTE_LIBRTE_RING) := rte_ring.c
 # install includes
 SYMLINK-$(CONFIG_RTE_LIBRTE_RING)-include := rte_ring.h
 
-# this lib needs eal
-DEPDIRS-$(CONFIG_RTE_LIBRTE_RING) += lib/librte_eal
+# this lib needs eal and rte_malloc
+DEPDIRS-$(CONFIG_RTE_LIBRTE_RING) += lib/librte_eal lib/librte_malloc
 
 include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/lib/librte_ring/rte_ring.c b/lib/librte_ring/rte_ring.c
index 2fe4024..d2ff3fe 100644
--- a/lib/librte_ring/rte_ring.c
+++ b/lib/librte_ring/rte_ring.c
@@ -75,6 +75,7 @@
 #include <rte_log.h>
 #include <rte_memory.h>
 #include <rte_memzone.h>
+#include <rte_malloc.h>
 #include <rte_launch.h>
 #include <rte_tailq.h>
 #include <rte_eal.h>
@@ -89,7 +90,7 @@
 
 #include "rte_ring.h"
 
-TAILQ_HEAD(rte_ring_list, rte_ring);
+TAILQ_HEAD(rte_ring_list, rte_tailq_entry);
 
 /* true if x is a power of 2 */
 #define POWEROF2(x) ((((x)-1) & (x)) == 0)
@@ -155,6 +156,7 @@ rte_ring_create(const char *name, unsigned count, int socket_id,
 {
 	char mz_name[RTE_MEMZONE_NAMESIZE];
 	struct rte_ring *r;
+	struct rte_tailq_entry *te;
 	const struct rte_memzone *mz;
 	ssize_t ring_size;
 	int mz_flags = 0;
@@ -173,6 +175,13 @@ rte_ring_create(const char *name, unsigned count, int socket_id,
 		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_snprintf(mz_name, sizeof(mz_name), "%s%s", RTE_RING_MZ_PREFIX, name);
 
 	rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
@@ -186,10 +195,14 @@ rte_ring_create(const char *name, unsigned count, int socket_id,
 		/* no need to check return value here, we already checked the
 		 * arguments above */
 		rte_ring_init(r, name, count, flags);
-		TAILQ_INSERT_TAIL(ring_list, r, next);
+
+		te->data = (void *) r;
+
+		TAILQ_INSERT_TAIL(ring_list, te, next);
 	} else {
 		r = NULL;
 		RTE_LOG(ERR, RING, "Cannot reserve memory\n");
+		rte_free(te);
 	}
 	rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
 
@@ -272,7 +285,7 @@ rte_ring_dump(FILE *f, const struct rte_ring *r)
 void
 rte_ring_list_dump(FILE *f)
 {
-	const struct rte_ring *mp;
+	const struct rte_tailq_entry *te;
 	struct rte_ring_list *ring_list;
 
 	/* check that we have an initialised tail queue */
@@ -284,8 +297,8 @@ rte_ring_list_dump(FILE *f)
 
 	rte_rwlock_read_lock(RTE_EAL_TAILQ_RWLOCK);
 
-	TAILQ_FOREACH(mp, ring_list, next) {
-		rte_ring_dump(f, mp);
+	TAILQ_FOREACH(te, ring_list, next) {
+		rte_ring_dump(f, (struct rte_ring *) te->data);
 	}
 
 	rte_rwlock_read_unlock(RTE_EAL_TAILQ_RWLOCK);
@@ -295,7 +308,8 @@ rte_ring_list_dump(FILE *f)
 struct rte_ring *
 rte_ring_lookup(const char *name)
 {
-	struct rte_ring *r;
+	struct rte_tailq_entry *te;
+	struct rte_ring *r = NULL;
 	struct rte_ring_list *ring_list;
 
 	/* check that we have an initialized tail queue */
@@ -307,15 +321,18 @@ rte_ring_lookup(const char *name)
 
 	rte_rwlock_read_lock(RTE_EAL_TAILQ_RWLOCK);
 
-	TAILQ_FOREACH(r, ring_list, next) {
+	TAILQ_FOREACH(te, ring_list, next) {
+		r = (struct rte_ring *) te->data;
 		if (strncmp(name, r->name, RTE_RING_NAMESIZE) == 0)
 			break;
 	}
 
 	rte_rwlock_read_unlock(RTE_EAL_TAILQ_RWLOCK);
 
-	if (r == NULL)
+	if (te == NULL) {
 		rte_errno = ENOENT;
+		return NULL;
+	}
 
 	return r;
 }
diff --git a/lib/librte_ring/rte_ring.h b/lib/librte_ring/rte_ring.h
index 4f3e20f..3920830 100644
--- a/lib/librte_ring/rte_ring.h
+++ b/lib/librte_ring/rte_ring.h
@@ -138,8 +138,6 @@ struct rte_ring_debug_stats {
  * a problem.
  */
 struct rte_ring {
-	TAILQ_ENTRY(rte_ring) next;      /**< Next in list. */
-
 	char name[RTE_RING_NAMESIZE];    /**< Name of the ring. */
 	int flags;                       /**< Flags supplied at creation. */
 
-- 
1.8.1.4