Hi Vadim,
> -----Original Message-----
> From: vadim.suraev at gmail.com [mailto:vadim.suraev at gmail.com]
> Sent: Tuesday, March 17, 2015 9:36 PM
> To: dev at dpdk.org
> Cc: olivier.matz at 6wind.com; stephen at networkplumber.org; Ananyev,
> Konstantin; vadim.suraev at gmail.com
> Subject: [PATCH v2] rte_mbuf: mbuf bulk alloc/free functions added + unittest
>
> From: "vadim.suraev at gmail.com" <vadim.suraev at gmail.com>
>
> This patch adds mbuf bulk allocation/freeing functions and unittest
>
> Signed-off-by: Vadim Suraev
> <vadim.suraev at gmail.com>
> ---
> New in v2:
> - function rte_pktmbuf_alloc_bulk added
> - function rte_pktmbuf_bulk_free added
> - function rte_pktmbuf_free_chain added
> - applied reviewers' comments
>
> 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..995237d 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 1
> + * as well as the freed mbufs are direct
I think your forgot to mention in comments one more requirement for that
function:
all mbufs have to be from the same mempool.
> + *
> + * @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);
You can do just:
rte_mbuf_refcnt_set(m, 0);
here and move your assert above it.
Something like:
RTE_MBUF_ASSERT(rte_mbuf_refcnt_read(mbufs[idx]) == 1);
rte_mbuf_refcnt_set(m, 0);
Also probably would be a good thing to add one more assert here,
something like:
RTE_MBUF_ASSERT(mbufs[idx]->pool == mufs[0]->pool);
> + 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;
Shouldn't the line above be inside if (head != NULL) {...} block?
> + head = __rte_pktmbuf_prefree_seg(head);
> + if (likely(head != NULL)) {
> + RTE_MBUF_ASSERT(rte_mbuf_refcnt_read(head) == 0);
I don't think there is any use of the assert above.
If prefree_seg returns non-NULL value, it sets refcnt to 0 for that mbuf.
> + 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
