[PATCH v7 2/5] lib/mbuf: introduce helper to create mempool with flags

[Xiaolong Ye <xiaolong.ye@intel.com>]

This allows applications to create mbuf mempool with specific flags
such as MEMPOOL_F_NO_SPREAD if they want fixed size memory objects.

Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>
Signed-off-by: Xiaolong Ye <xiaolong.ye@intel.com>
---
 lib/librte_mbuf/rte_mbuf.c           | 29 ++++++++++++++----
 lib/librte_mbuf/rte_mbuf.h           | 45 ++++++++++++++++++++++++++++
 lib/librte_mbuf/rte_mbuf_version.map |  1 +
 3 files changed, 70 insertions(+), 5 deletions(-)

diff --git a/lib/librte_mbuf/rte_mbuf.c b/lib/librte_mbuf/rte_mbuf.c
index 21f6f7404..c1db9e298 100644
--- a/lib/librte_mbuf/rte_mbuf.c
+++ b/lib/librte_mbuf/rte_mbuf.c
@@ -106,11 +106,10 @@ rte_pktmbuf_init(struct rte_mempool *mp,
 	m->next = NULL;
 }
 
-/* Helper to create a mbuf pool with given mempool ops name*/
-struct rte_mempool *
-rte_pktmbuf_pool_create_by_ops(const char *name, unsigned int n,
+static struct rte_mempool *
+rte_pktmbuf_pool_create_by_ops_with_flags(const char *name, unsigned int n,
 	unsigned int cache_size, uint16_t priv_size, uint16_t data_room_size,
-	int socket_id, const char *ops_name)
+	unsigned int flags, int socket_id, const char *ops_name)
 {
 	struct rte_mempool *mp;
 	struct rte_pktmbuf_pool_private mbp_priv;
@@ -130,7 +129,7 @@ rte_pktmbuf_pool_create_by_ops(const char *name, unsigned int n,
 	mbp_priv.mbuf_priv_size = priv_size;
 
 	mp = rte_mempool_create_empty(name, n, elt_size, cache_size,
-		 sizeof(struct rte_pktmbuf_pool_private), socket_id, 0);
+		 sizeof(struct rte_pktmbuf_pool_private), socket_id, flags);
 	if (mp == NULL)
 		return NULL;
 
@@ -157,6 +156,16 @@ rte_pktmbuf_pool_create_by_ops(const char *name, unsigned int n,
 	return mp;
 }
 
+/* Helper to create a mbuf pool with given mempool ops name*/
+struct rte_mempool *
+rte_pktmbuf_pool_create_by_ops(const char *name, unsigned int n,
+	unsigned int cache_size, uint16_t priv_size, uint16_t data_room_size,
+	int socket_id, const char *ops_name)
+{
+	return rte_pktmbuf_pool_create_by_ops_with_flags(name, n, cache_size,
+			 priv_size, data_room_size, 0, socket_id, ops_name);
+}
+
 /* helper to create a mbuf pool */
 struct rte_mempool *
 rte_pktmbuf_pool_create(const char *name, unsigned int n,
@@ -167,6 +176,16 @@ rte_pktmbuf_pool_create(const char *name, unsigned int n,
 			data_room_size, socket_id, NULL);
 }
 
+/* helper to create a mbuf pool with flags (e.g. NO_SPREAD) */
+struct rte_mempool * __rte_experimental
+rte_pktmbuf_pool_create_with_flags(const char *name, unsigned int n,
+	unsigned int cache_size, uint16_t priv_size, uint16_t data_room_size,
+	unsigned int flags, int socket_id)
+{
+	return rte_pktmbuf_pool_create_by_ops_with_flags(name, n, cache_size,
+			priv_size, data_room_size, flags, socket_id, NULL);
+}
+
 /* do some sanity checks on a mbuf: panic if it fails */
 void
 rte_mbuf_sanity_check(const struct rte_mbuf *m, int is_header)
diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index d961ccaf6..105ead6de 100644
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h
@@ -1266,6 +1266,51 @@ rte_pktmbuf_pool_create(const char *name, unsigned n,
 	unsigned cache_size, uint16_t priv_size, uint16_t data_room_size,
 	int socket_id);
 
+/**
+ * Create a mbuf pool with flags.
+ *
+ * This function creates and initializes a packet mbuf pool. It is
+ * a wrapper to rte_mempool functions.
+ *
+ * @warning
+ * @b EXPERIMENTAL: This API may change without prior notice.
+ *
+ * @param name
+ *   The name of the mbuf pool.
+ * @param n
+ *   The number of elements in the mbuf pool. The optimum size (in terms
+ *   of memory usage) for a mempool is when n is a power of two minus one:
+ *   n = (2^q - 1).
+ * @param cache_size
+ *   Size of the per-core object cache. See rte_mempool_create() for
+ *   details.
+ * @param priv_size
+ *   Size of application private are between the rte_mbuf structure
+ *   and the data buffer. This value must be aligned to RTE_MBUF_PRIV_ALIGN.
+ * @param data_room_size
+ *   Size of data buffer in each mbuf, including RTE_PKTMBUF_HEADROOM.
+ * @param flags
+ *   Flags controlling the behavior of the mempool. See
+ *   rte_mempool_create() for details.
+ * @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
+ *   reserved zone.
+ * @return
+ *   The pointer to the new allocated mempool, on success. NULL on error
+ *   with rte_errno set appropriately. Possible rte_errno values include:
+ *    - E_RTE_NO_CONFIG - function could not get pointer to rte_config structure
+ *    - E_RTE_SECONDARY - function was called from a secondary process instance
+ *    - EINVAL - cache size provided is too large, or priv_size is not aligned.
+ *    - ENOSPC - the maximum number of memzones has already been allocated
+ *    - EEXIST - a memzone with the same name already exists
+ *    - ENOMEM - no appropriate memory area found in which to create memzone
+ */
+struct rte_mempool * __rte_experimental
+rte_pktmbuf_pool_create_with_flags(const char *name, unsigned int n,
+	unsigned int cache_size, uint16_t priv_size, uint16_t data_room_size,
+	unsigned int flags, int socket_id);
+
 /**
  * Create a mbuf pool with a given mempool ops name
  *
diff --git a/lib/librte_mbuf/rte_mbuf_version.map b/lib/librte_mbuf/rte_mbuf_version.map
index 2662a37bf..2579538e0 100644
--- a/lib/librte_mbuf/rte_mbuf_version.map
+++ b/lib/librte_mbuf/rte_mbuf_version.map
@@ -50,4 +50,5 @@ EXPERIMENTAL {
 	global:
 
 	rte_mbuf_check;
+	rte_pktmbuf_pool_create_with_flags;
 } DPDK_18.08;
-- 
2.17.1