[v6,1/2] mbuf: add bulk free function
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Commit Message
Add function for freeing a bulk of mbufs.
v6:
* Remove __rte_always_inline from static function.
The compiler will inline anyway.
v5:
* Rename variables from "free" to "pending" for improved readability.
* Add prefix __ to rte_pktmbuf_free_seg_via_array().
* Add array size parameter to __rte_pktmbuf_free_seg_via_array().
The compiler will optimize the parameter away anyway.
* Add description to __rte_pktmbuf_free_seg_via_array().
* Minor description updates.
v4:
* Mark as experimental by adding __rte_experimental.
* Add function to experimental section of map file.
* Fix source code formatting regarding pointer to pointer.
* Squash multiple modifications into one.
v3:
* Bugfix: Handle pakets with multiple segments.
* Add inline helper function, mainly for readability.
* Fix source code formatting regarding indentation.
v2:
* Function is not inline.
* Optimize to free multible mbufs belonging to the same mempool in
bulk. Inspired by ixgbe_tx_free_bufs(), but allowing NULL pointers
in the array, just like rte_pktmbuf_free() can take a NULL pointer.
* Use unsigned int instead of unsigned. Passes checkpatch, but
mismatches the original coding style of the modified files.
* Fix a typo in the description headline: mempools is plural.
Signed-off-by: Morten Brørup <mb@smartsharesystems.com>
---
lib/librte_mbuf/rte_mbuf.c | 66 ++++++++++++++++++++++++++++
lib/librte_mbuf/rte_mbuf.h | 15 +++++++
lib/librte_mbuf/rte_mbuf_version.map | 1 +
3 files changed, 82 insertions(+)
@@ -245,6 +245,72 @@ int rte_mbuf_check(const struct rte_mbuf *m, int is_header,
return 0;
}
+/**
+ * @internal helper function for freeing a bulk of packet mbuf segments
+ * via an array holding the packet mbuf segments from the same mempool
+ * pending to be freed.
+ *
+ * @param m
+ * The packet mbuf segment to be freed.
+ * @param pending
+ * Pointer to the array of packet mbuf segments pending to be freed.
+ * @param nb_pending
+ * Pointer to the number of elements held in the array.
+ * @param pending_sz
+ * Number of elements the array can hold.
+ * Note: The compiler should optimize this parameter away when using a
+ * constant value, such as RTE_PKTMBUF_FREE_PENDING_SZ.
+ */
+static __rte_always_inline void
+__rte_pktmbuf_free_seg_via_array(struct rte_mbuf *m,
+ struct rte_mbuf ** const pending, unsigned int * const nb_pending,
+ const unsigned int pending_sz)
+{
+ m = rte_pktmbuf_prefree_seg(m);
+ if (likely(m != NULL)) {
+ if (*nb_pending == pending_sz ||
+ (*nb_pending > 0 && m->pool != pending[0]->pool)) {
+ rte_mempool_put_bulk(pending[0]->pool,
+ (void **)pending, *nb_pending);
+ *nb_pending = 0;
+ }
+
+ pending[(*nb_pending)++] = m;
+ }
+}
+
+/**
+ * Size of the array holding mbufs from the same membool pending to be freed
+ * in bulk.
+ */
+#define RTE_PKTMBUF_FREE_PENDING_SZ 64
+
+/* Free a bulk of packet mbufs back into their original mempools. */
+void rte_pktmbuf_free_bulk(struct rte_mbuf **mbufs, unsigned int count)
+{
+ struct rte_mbuf *m, *m_next, *pending[RTE_PKTMBUF_FREE_PENDING_SZ];
+ unsigned int idx, nb_pending = 0;
+
+ for (idx = 0; idx < count; idx++) {
+ m = mbufs[idx];
+ if (unlikely(m == NULL))
+ continue;
+
+ __rte_mbuf_sanity_check(m, 1);
+
+ do {
+ m_next = m->next;
+ __rte_pktmbuf_free_seg_via_array(m,
+ pending, &nb_pending,
+ RTE_PKTMBUF_FREE_PENDING_SZ);
+ m = m_next;
+ } while (m != NULL);
+ }
+
+ if (nb_pending > 0)
+ rte_mempool_put_bulk(pending[0]->pool, (void **)pending, nb_pending);
+}
+
/* dump a mbuf on console */
void
rte_pktmbuf_dump(FILE *f, const struct rte_mbuf *m, unsigned dump_len)
@@ -1907,6 +1907,21 @@ static inline void rte_pktmbuf_free(struct rte_mbuf *m)
}
}
+/**
+ * Free a bulk of packet mbufs back into their original mempools.
+ *
+ * Free a bulk of mbufs, and all their segments in case of chained buffers.
+ * Each segment is added back into its original mempool.
+ *
+ * @param mbufs
+ * Array of pointers to packet mbufs.
+ * The array may contain NULL pointers.
+ * @param count
+ * Array size.
+ */
+__rte_experimental
+void rte_pktmbuf_free_bulk(struct rte_mbuf **mbufs, unsigned int count);
+
/**
* Creates a "clone" of the given packet mbuf.
*
@@ -50,4 +50,5 @@ EXPERIMENTAL {
global:
rte_mbuf_check;
+ rte_pktmbuf_free_bulk;
} DPDK_18.08;