[dpdk-dev] [PATCH] rte_mbuf: mbuf bulk alloc/free functions added + unittest

[dpdk-dev] [PATCH] rte_mbuf: mbuf bulk alloc/free functions added + unittest

[vadim.suraev]

From: "vadim.suraev@gmail.com" <vadim.suraev@gmail.com>

- an API function to allocate a bulk of rte_mbufs
- an API function to free a bulk of rte_mbufs
- an API function to free a chained rte_mbuf
- unittest for above

Signed-off-by: vadim.suraev@gmail.com <vadim.suraev@gmail.com>
---
 app/test/test_mbuf.c       |   94 +++++++++++++++++++++++++++++++++++++++++++-
 lib/librte_mbuf/rte_mbuf.h |   89 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 182 insertions(+), 1 deletion(-)

diff --git a/app/test/test_mbuf.c b/app/test/test_mbuf.c
index 1ff66cb..b20c6a4 100644
--- a/app/test/test_mbuf.c
+++ b/app/test/test_mbuf.c
@@ -77,6 +77,7 @@
 #define REFCNT_RING_SIZE        (REFCNT_MBUF_NUM * REFCNT_MAX_REF)
 
 #define MAKE_STRING(x)          # x
+#define MBUF_POOL_LOCAL_CACHE_SIZE 32
 
 static struct rte_mempool *pktmbuf_pool = NULL;
 
@@ -405,6 +406,84 @@ test_pktmbuf_pool(void)
 	return ret;
 }
 
+/* test pktmbuf bulk allocation and freeing
+*/
+static int
+test_pktmbuf_pool_bulk(void)
+{
+	unsigned i;
+	/* size of mempool - size of local cache, otherwise may fail */
+	unsigned mbufs_to_allocate = NB_MBUF - MBUF_POOL_LOCAL_CACHE_SIZE;
+	struct rte_mbuf *m[mbufs_to_allocate];
+	int ret = 0;
+	unsigned mbuf_count_before_allocation = rte_mempool_count(pktmbuf_pool);
+
+	for (i = 0; i < mbufs_to_allocate; i++)
+		m[i] = NULL;
+	/* alloc NB_MBUF-MBUF_POOL_LOCAL_CACHE_SIZE mbufs */
+	ret = rte_pktmbuf_alloc_bulk(pktmbuf_pool, m, mbufs_to_allocate);
+	if (ret) {
+		printf("cannot allocate %d mbufs bulk mempool_cnt=%d ret=%d\n",
+			mbufs_to_allocate,
+			rte_mempool_count(pktmbuf_pool),
+			ret);
+		return -1;
+	}
+	if ((rte_mempool_count(pktmbuf_pool) + mbufs_to_allocate) !=
+	    mbuf_count_before_allocation) {
+		printf("mempool count %d + allocated %d != initial %d\n",
+			rte_mempool_count(pktmbuf_pool),
+			mbufs_to_allocate,
+			mbuf_count_before_allocation);
+		return -1;
+	}
+	/* free them */
+	rte_pktmbuf_bulk_free(m, mbufs_to_allocate);
+
+	if (rte_mempool_count(pktmbuf_pool)  != mbuf_count_before_allocation) {
+		printf("mempool count %d != initial %d\n",
+			rte_mempool_count(pktmbuf_pool),
+			mbuf_count_before_allocation);
+		return -1;
+	}
+	for (i = 0; i < mbufs_to_allocate; i++)
+		m[i] = NULL;
+
+	/* alloc NB_MBUF-MBUF_POOL_LOCAL_CACHE_SIZE mbufs */
+	ret = rte_pktmbuf_alloc_bulk(pktmbuf_pool, m, mbufs_to_allocate);
+	if (ret) {
+		printf("cannot allocate %d mbufs bulk mempool_cnt=%d ret=%d\n",
+			mbufs_to_allocate,
+			rte_mempool_count(pktmbuf_pool),
+			ret);
+		return -1;
+	}
+	if ((rte_mempool_count(pktmbuf_pool) + mbufs_to_allocate) !=
+	    mbuf_count_before_allocation) {
+		printf("mempool count %d + allocated %d != initial %d\n",
+			rte_mempool_count(pktmbuf_pool),
+					  mbufs_to_allocate,
+					  mbuf_count_before_allocation);
+		return -1;
+	}
+
+	/* chain it */
+	for (i = 0; i < mbufs_to_allocate - 1; i++) {
+		m[i]->next = m[i + 1];
+		m[0]->nb_segs++;
+	}
+	/* free them */
+	rte_pktmbuf_free_chain(m[0]);
+
+	if (rte_mempool_count(pktmbuf_pool)  != mbuf_count_before_allocation) {
+		printf("mempool count %d != initial %d\n",
+			rte_mempool_count(pktmbuf_pool),
+					  mbuf_count_before_allocation);
+		return -1;
+	}
+	return ret;
+}
+
 /*
  * test that the pointer to the data on a packet mbuf is set properly
  */
@@ -766,7 +845,8 @@ test_mbuf(void)
 	if (pktmbuf_pool == NULL) {
 		pktmbuf_pool =
 			rte_mempool_create("test_pktmbuf_pool", NB_MBUF,
-					   MBUF_SIZE, 32,
+					   MBUF_SIZE,
+					   MBUF_POOL_LOCAL_CACHE_SIZE,
 					   sizeof(struct rte_pktmbuf_pool_private),
 					   rte_pktmbuf_pool_init, NULL,
 					   rte_pktmbuf_init, NULL,
@@ -790,6 +870,18 @@ test_mbuf(void)
 		return -1;
 	}
 
+	/* test bulk allocation and freeing */
+	if (test_pktmbuf_pool_bulk() < 0) {
+		printf("test_pktmbuf_pool_bulk() failed\n");
+		return -1;
+	}
+
+	/* once again to ensure all mbufs were freed */
+	if (test_pktmbuf_pool_bulk() < 0) {
+		printf("test_pktmbuf_pool_bulk() failed\n");
+		return -1;
+	}
+
 	/* test that the pointer to the data on a packet mbuf is set properly */
 	if (test_pktmbuf_pool_ptr() < 0) {
 		printf("test_pktmbuf_pool_ptr() failed\n");
diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index 17ba791..a5029a0 100644
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h
@@ -825,6 +825,95 @@ static inline void rte_pktmbuf_free(struct rte_mbuf *m)
 }
 
 /**
+ * Allocate a bulk of mbufs, initiate refcnt and resets
+ *
+ * @param pool
+ *    memory pool to allocate from
+ * @param mbufs
+ *    Array of pointers to mbuf
+ * @param count
+ *    Array size
+ */
+static inline int rte_pktmbuf_alloc_bulk(struct rte_mempool *pool,
+					 struct rte_mbuf **mbufs,
+					 unsigned count)
+{
+	unsigned idx;
+	int rc = 0;
+
+	rc = rte_mempool_get_bulk(pool, (void **)mbufs, count);
+	if (unlikely(rc))
+		return rc;
+
+	for (idx = 0; idx < count; idx++) {
+		RTE_MBUF_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
+		rte_mbuf_refcnt_set(mbufs[idx], 1);
+		rte_pktmbuf_reset(mbufs[idx]);
+	}
+	return rc;
+}
+
+/**
+ * Free a bulk of mbufs into its original mempool.
+ * This function assumes refcnt equals 0
+ * as well as the freed mbufs are direct
+ *
+ * @param mbufs
+ *    Array of pointers to mbuf
+ * @param count
+ *    Array size
+ */
+static inline void rte_pktmbuf_bulk_free(struct rte_mbuf **mbufs,
+					 unsigned count)
+{
+	unsigned idx;
+
+	RTE_MBUF_ASSERT(count > 0);
+
+	for (idx = 0; idx < count; idx++) {
+		rte_mbuf_refcnt_update(mbufs[idx], -1);
+		RTE_MBUF_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 0);
+	}
+	rte_mempool_put_bulk(mbufs[0]->pool, (void **)mbufs, count);
+}
+
+/**
+ * Free chained (scattered) mbufs into its original mempool(s).
+ *
+ * @param head
+ *    The head of mbufs to be freed chain. Must not be NULL
+ */
+static inline void rte_pktmbuf_free_chain(struct rte_mbuf *head)
+{
+	struct rte_mbuf *mbufs[head->nb_segs];
+	unsigned mbufs_count = 0;
+	struct rte_mbuf *next;
+
+	while (head) {
+		next = head->next;
+		head->next = NULL;
+		head = __rte_pktmbuf_prefree_seg(head);
+		if (likely(head != NULL)) {
+			RTE_MBUF_ASSERT(rte_mbuf_refcnt_read(head) == 0);
+			if (likely((!mbufs_count) ||
+				   (head->pool == mbufs[0]->pool)))
+				mbufs[mbufs_count++] = head;
+			else {
+				rte_mempool_put_bulk(mbufs[0]->pool,
+						     (void **)mbufs,
+						     mbufs_count);
+				mbufs_count = 0;
+			}
+		}
+		head = next;
+	}
+	if (mbufs_count > 0)
+		rte_mempool_put_bulk(mbufs[0]->pool,
+				     (void **)mbufs,
+				     mbufs_count);
+}
+
+/**
  * Creates a "clone" of the given packet mbuf.
  *
  * Walks through all segments of the given packet mbuf, and for each of them:
-- 
1.7.9.5

Re: [dpdk-dev] [PATCH] rte_mbuf: mbuf bulk alloc/free functions added + unittest

[Thomas Monjalon]

Hi Vadim,

It would be easier to track your changes if you were adding v2 and changelog.
Thanks

2015-03-17 22:16, vadim.suraev@gmail.com:
> From: "vadim.suraev@gmail.com" <vadim.suraev@gmail.com>
> 
> - an API function to allocate a bulk of rte_mbufs
> - an API function to free a bulk of rte_mbufs
> - an API function to free a chained rte_mbuf
> - unittest for above
> 
> Signed-off-by: vadim.suraev@gmail.com <vadim.suraev@gmail.com>

You should put your name before the email address.

> ---
>  app/test/test_mbuf.c       |   94 +++++++++++++++++++++++++++++++++++++++++++-
>  lib/librte_mbuf/rte_mbuf.h |   89 +++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 182 insertions(+), 1 deletion(-)