ethdev: add mbuf fast free Tx offload

PMDs which expose this offload cap supports optimization for fast release
of mbufs following successful Tx.
Such optimization requires that per queue, all mbufs come from the same
mempool and has refcnt = 1.

Signed-off-by: Shahaf Shuler <shahafs@mellanox.com>
Reviewed-by: Andrew Rybchenko <arybchenko@solarflare.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>

diff --git a/doc/guides/nics/features.rst b/doc/guides/nics/features.rst
index 17745dace004c4794913d923a3c02371b067f3a5..6538470ac7d71f08f429170681040ab1c6ae684e 100644 (file)
--- a/doc/guides/nics/features.rst
+++ b/doc/guides/nics/features.rst
@@ -628,6 +628,15 @@ Supports packet type parsing and returns a list of supported types.
 
 .. _nic_features_timesync:
 
+Mbuf fast free
+--------------
+
+Supports optimization for fast release of mbufs following successful Tx.
+Requires that per queue, all mbufs come from the same mempool and has refcnt = 1.
+
+* **[uses]       rte_eth_txconf,rte_eth_txmode**: ``offloads:DEV_TX_OFFLOAD_MBUF_FAST_FREE``.
+* **[provides]   rte_eth_dev_info**: ``tx_offload_capa,tx_queue_offload_capa:DEV_TX_OFFLOAD_MBUF_FAST_FREE``.
+
 Timesync
 --------
 

diff --git a/doc/guides/nics/features/default.ini b/doc/guides/nics/features/default.ini
index 5424306964bae05e8ebced493537cecc17c2a563..9a599019555daafb148bb34f392428fbc917ef33 100644 (file)
--- a/doc/guides/nics/features/default.ini
+++ b/doc/guides/nics/features/default.ini
@@ -75,3 +75,4 @@ x86-64               =
 Usage doc            =
 Design doc           =
 Perf doc             =
+Mbuf fast free       =

diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index 856a54a8efdccf3f92b6fdbebc2a9127c1e8ea75..59756dd822b6cf05ace7fc2877c797eae9a88e0c 100644 (file)
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -1232,6 +1232,9 @@ rte_eth_convert_txq_flags(const uint32_t txq_flags, uint64_t *tx_offloads)
                offloads |= DEV_TX_OFFLOAD_UDP_CKSUM;
        if (!(txq_flags & ETH_TXQ_FLAGS_NOXSUMTCP))
                offloads |= DEV_TX_OFFLOAD_TCP_CKSUM;
+       if ((txq_flags & ETH_TXQ_FLAGS_NOREFCOUNT) &&
+           (txq_flags & ETH_TXQ_FLAGS_NOMULTMEMP))
+               offloads |= DEV_TX_OFFLOAD_MBUF_FAST_FREE;
 
        *tx_offloads = offloads;
 }
@@ -1254,6 +1257,8 @@ rte_eth_convert_txq_offloads(const uint64_t tx_offloads, uint32_t *txq_flags)
                flags |= ETH_TXQ_FLAGS_NOXSUMUDP;
        if (!(tx_offloads & DEV_TX_OFFLOAD_TCP_CKSUM))
                flags |= ETH_TXQ_FLAGS_NOXSUMTCP;
+       if (tx_offloads & DEV_TX_OFFLOAD_MBUF_FAST_FREE)
+               flags |= (ETH_TXQ_FLAGS_NOREFCOUNT | ETH_TXQ_FLAGS_NOMULTMEMP);
 
        *txq_flags = flags;
 }

diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index da91f8740526760f662d4a275b3edabc3322f4a6..78de045ed9f51805f9ffa2cd62a43b5d2ebf38d6 100644 (file)
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -991,6 +991,11 @@ struct rte_eth_conf {
  */
 #define DEV_TX_OFFLOAD_MULTI_SEGS      0x00008000
 /**< Device supports multi segment send. */
+#define DEV_TX_OFFLOAD_MBUF_FAST_FREE  0x00010000
+/**< Device supports optimization for fast release of mbufs.
+ *   When set application must guarantee that per-queue all mbufs comes from
+ *   the same mempool and has refcnt = 1.
+ */
 
 struct rte_pci_device;