[PATCH v4 05/31] net/ena: fix fast mbuf free

[PATCH v4 05/31] net/ena: fix fast mbuf free

[shaibran]

From: Shai Brandes <shaibran@amazon.com>

In case the application enables fast mbuf release optimization,
the driver releases 256 TX mbufs in bulk upon reaching the
TX free threshold.
The existing implementation utilizes rte_mempool_put_bulk for bulk
freeing TXs, which exclusively supports direct mbufs.
In case the application transmits indirect bufs, the driver must
also decrement the mbuf reference count and unlink the mbuf segment.
For such case, the driver should employ rte_pktmbuf_free_bulk.

Fixes: c339f53823f3 ("net/ena: support fast mbuf free")
Cc: stable@dpdk.org

Signed-off-by: Shai Brandes <shaibran@amazon.com>
Reviewed-by: Amit Bernstein <amitbern@amazon.com>
---
 doc/guides/rel_notes/release_24_03.rst | 1 +
 drivers/net/ena/ena_ethdev.c           | 6 ++----
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/doc/guides/rel_notes/release_24_03.rst b/doc/guides/rel_notes/release_24_03.rst
index a30be47241..cbd4669cbb 100644
--- a/doc/guides/rel_notes/release_24_03.rst
+++ b/doc/guides/rel_notes/release_24_03.rst
@@ -107,6 +107,7 @@ New Features
 
   * Removed the reporting of `rx_overruns` errors from xstats and instead updated `imissed` stat with its value.
   * Added support for sub-optimal configuration notifications from the device.
+  * Restructured fast release of mbufs when RTE_ETH_TX_OFFLOAD_MBUF_FAST_FREE optimization is enabled.
 
 * **Updated Atomic Rules' Arkville driver.**
 
diff --git a/drivers/net/ena/ena_ethdev.c b/drivers/net/ena/ena_ethdev.c
index 3157237c0d..537ee9f8c3 100644
--- a/drivers/net/ena/ena_ethdev.c
+++ b/drivers/net/ena/ena_ethdev.c
@@ -3122,8 +3122,7 @@ ena_tx_cleanup_mbuf_fast(struct rte_mbuf **mbufs_to_clean,
 		m_next = mbuf->next;
 		mbufs_to_clean[mbuf_cnt++] = mbuf;
 		if (mbuf_cnt == buf_size) {
-			rte_mempool_put_bulk(mbufs_to_clean[0]->pool, (void **)mbufs_to_clean,
-				(unsigned int)mbuf_cnt);
+			rte_pktmbuf_free_bulk(mbufs_to_clean, mbuf_cnt);
 			mbuf_cnt = 0;
 		}
 		mbuf = m_next;
@@ -3191,8 +3190,7 @@ static int ena_tx_cleanup(void *txp, uint32_t free_pkt_cnt)
 	}
 
 	if (mbuf_cnt != 0)
-		rte_mempool_put_bulk(mbufs_to_clean[0]->pool,
-			(void **)mbufs_to_clean, mbuf_cnt);
+		rte_pktmbuf_free_bulk(mbufs_to_clean, mbuf_cnt);
 
 	/* Notify completion handler that full cleanup was performed */
 	if (free_pkt_cnt == 0 || total_tx_pkts < cleanup_budget)
-- 
2.17.1

Re: [PATCH v4 05/31] net/ena: fix fast mbuf free

[Ferruh Yigit]

On 3/12/2024 6:06 PM, shaibran@amazon.com wrote:
> From: Shai Brandes <shaibran@amazon.com>
> 
> In case the application enables fast mbuf release optimization,
> the driver releases 256 TX mbufs in bulk upon reaching the
> TX free threshold.
> The existing implementation utilizes rte_mempool_put_bulk for bulk
> freeing TXs, which exclusively supports direct mbufs.
> In case the application transmits indirect bufs, the driver must
> also decrement the mbuf reference count and unlink the mbuf segment.
> For such case, the driver should employ rte_pktmbuf_free_bulk.
> 
> Fixes: c339f53823f3 ("net/ena: support fast mbuf free")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Shai Brandes <shaibran@amazon.com>
> Reviewed-by: Amit Bernstein <amitbern@amazon.com>
>

Dropped release notes update while merging, as user impact of the change
is low, or no more than fixing a defect.