The l2_len and l3_len fields are used for TX offloads and so should be
put on the second cache line, along with the other fields only used on
TX.
Updates in V2:
* The l2 and l3 lengths can be accessed as a single uint16_t for
performance, as well as individually.
Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
---
lib/librte_mbuf/rte_mbuf.h | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)
diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index 508021b..1c6e115 100644
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h
@@ -159,13 +159,7 @@ struct rte_mbuf {
uint16_t reserved2; /**< Unused field. Required for padding */
uint16_t data_len; /**< Amount of data in segment buffer. */
uint32_t pkt_len; /**< Total pkt len: sum of all segments. */
- union {
- uint16_t l2_l3_len; /**< combined l2/l3 lengths as single var */
- struct {
- uint16_t l3_len:9; /**< L3 (IP) Header Length. */
- uint16_t l2_len:7; /**< L2 (MAC) Header Length. */
- };
- };
+ uint16_t reserved;
uint16_t vlan_tci; /**< VLAN Tag Control Identifier (CPU order)
*/
union {
uint32_t rss; /**< RSS hash result if RSS enabled */
@@ -181,6 +175,14 @@ struct rte_mbuf {
struct rte_mempool *pool; /**< Pool from which mbuf was allocated. */
struct rte_mbuf *next; /**< Next segment of scattered packet. */
+ /* fields to support TX offloads */
+ union {
+ uint16_t l2_l3_len; /**< combined l2/l3 lengths as single var */
+ struct {
+ uint16_t l3_len:9; /**< L3 (IP) Header Length. */
+ uint16_t l2_len:7; /**< L2 (MAC) Header Length. */
+ };
+ };
} __rte_cache_aligned;
/**
--
1.9.3
