[dpdk-dev] [PATCH v2 9/9] mbuf: remove seqn field

[David Marchand <david.marchand@redhat.com>]

As announced in the deprecation note, the field seqn is removed to give
more space to the dynamic fields.

This is how the mbuf layout looks like (pahole-style):

word  type                              name                byte  size
 0    void *                            buf_addr;         /*   0 +  8 */
 1    rte_iova_t                        buf_iova          /*   8 +  8 */
      /* --- RTE_MARKER64               rearm_data;                   */
 2    uint16_t                          data_off;         /*  16 +  2 */
      uint16_t                          refcnt;           /*  18 +  2 */
      uint16_t                          nb_segs;          /*  20 +  2 */
      uint16_t                          port;             /*  22 +  2 */
 3    uint64_t                          ol_flags;         /*  24 +  8 */
      /* --- RTE_MARKER                 rx_descriptor_fields1;        */
 4    uint32_t             union        packet_type;      /*  32 +  4 */
      uint32_t                          pkt_len;          /*  36 +  4 */
 5    uint16_t                          data_len;         /*  40 +  2 */
      uint16_t                          vlan_tci;         /*  42 +  2 */
 5.5  uint64_t             union        hash;             /*  44 +  8 */
 6.5  uint16_t                          vlan_tci_outer;   /*  52 +  2 */
      uint16_t                          buf_len;          /*  54 +  2 */
 7    uint64_t                          timestamp;        /*  56 +  8 */
      /* --- RTE_MARKER                 cacheline1;                   */
 8    struct rte_mempool *              pool;             /*  64 +  8 */
 9    struct rte_mbuf *                 next;             /*  72 +  8 */
10    uint64_t             union        tx_offload;       /*  80 +  8 */
11    struct rte_mbuf_ext_shared_info * shinfo;           /*  88 +  8 */
12    uint16_t                          priv_size;        /*  96 +  2 */
      uint16_t                          timesync;         /*  98 +  2 */
12.5  uint32_t                          dynfield1[7];     /* 100 + 28 */
16    /* --- END                                             128      */

Signed-off-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
---
 doc/guides/rel_notes/deprecation.rst   |  1 -
 doc/guides/rel_notes/release_20_11.rst |  3 +++
 lib/librte_mbuf/rte_mbuf_core.h        | 15 ++++++---------
 3 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst
index 0f6f1df12a..fe3fd3956c 100644
--- a/doc/guides/rel_notes/deprecation.rst
+++ b/doc/guides/rel_notes/deprecation.rst
@@ -87,7 +87,6 @@ Deprecation Notices
   The following static fields will be moved as dynamic:
 
   - ``timestamp``
-  - ``seqn``
 
   As a consequence, the layout of the ``struct rte_mbuf`` will be re-arranged,
   avoiding impact on vectorized implementation of the driver datapaths,
diff --git a/doc/guides/rel_notes/release_20_11.rst b/doc/guides/rel_notes/release_20_11.rst
index 3d7edbfdbb..c0a9fc96aa 100644
--- a/doc/guides/rel_notes/release_20_11.rst
+++ b/doc/guides/rel_notes/release_20_11.rst
@@ -429,6 +429,9 @@ API Changes
 * mbuf: Removed the unioned fields ``userdata`` and ``udata64``
   from the structure ``rte_mbuf``. It is replaced with dynamic fields.
 
+* mbuf: Removed the field ``seqn`` from the structure ``rte_mbuf``.
+  It is replaced with dynamic fields.
+
 * pci: Removed the ``rte_kernel_driver`` enum defined in rte_dev.h and
   replaced with a private enum in the PCI subsystem.
 
diff --git a/lib/librte_mbuf/rte_mbuf_core.h b/lib/librte_mbuf/rte_mbuf_core.h
index a65eaaf692..3fb5abda3c 100644
--- a/lib/librte_mbuf/rte_mbuf_core.h
+++ b/lib/librte_mbuf/rte_mbuf_core.h
@@ -640,6 +640,11 @@ struct rte_mbuf {
 		};
 	};
 
+	/** Shared data for external buffer attached to mbuf. See
+	 * rte_pktmbuf_attach_extbuf().
+	 */
+	struct rte_mbuf_ext_shared_info *shinfo;
+
 	/** Size of the application private data. In case of an indirect
 	 * mbuf, it stores the direct mbuf private data size.
 	 */
@@ -648,15 +653,7 @@ struct rte_mbuf {
 	/** Timesync flags for use with IEEE1588. */
 	uint16_t timesync;
 
-	/** Sequence number. See also rte_reorder_insert(). */
-	uint32_t seqn;
-
-	/** Shared data for external buffer attached to mbuf. See
-	 * rte_pktmbuf_attach_extbuf().
-	 */
-	struct rte_mbuf_ext_shared_info *shinfo;
-
-	uint64_t dynfield1[3]; /**< Reserved for dynamic fields. */
+	uint32_t dynfield1[7]; /**< Reserved for dynamic fields. */
 } __rte_cache_aligned;
 
 /**
-- 
2.23.0