[dpdk-dev] [PATCH 14/15] examples/rxtx_callbacks: switch to dynamic mbuf field

[Thomas Monjalon]

The example used the deprecated mbuf field udata64.
It is moved to a dynamic field in order to allow removal of udata64.

Note: RTE_MBUF_DYNFIELD_TIMESTAMP_NAME is an existing mbuf field name.

Signed-off-by: Thomas Monjalon <tho...@monjalon.net>
---
 doc/guides/sample_app_ug/rxtx_callbacks.rst |  4 ++--
 examples/rxtx_callbacks/main.c              | 19 +++++++++++++++++--
 2 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/doc/guides/sample_app_ug/rxtx_callbacks.rst 
b/doc/guides/sample_app_ug/rxtx_callbacks.rst
index 62d1f39d7e..8c3b49ae62 100644
--- a/doc/guides/sample_app_ug/rxtx_callbacks.rst
+++ b/doc/guides/sample_app_ug/rxtx_callbacks.rst
@@ -152,7 +152,7 @@ all packets received:
         uint64_t now = rte_rdtsc();
 
         for (i = 0; i < nb_pkts; i++)
-            pkts[i]->udata64 = now;
+            TIMESTAMP_FIELD(pkts[i]) = now;
 
         return nb_pkts;
     }
@@ -179,7 +179,7 @@ packets prior to transmission:
         unsigned i;
 
         for (i = 0; i < nb_pkts; i++)
-            cycles += now - pkts[i]->udata64;
+            cycles += now - TIMESTAMP_FIELD(pkts[i]);
 
         latency_numbers.total_cycles += cycles;
         latency_numbers.total_pkts   += nb_pkts;
diff --git a/examples/rxtx_callbacks/main.c b/examples/rxtx_callbacks/main.c
index 6fe39546dd..8f9852bf6f 100644
--- a/examples/rxtx_callbacks/main.c
+++ b/examples/rxtx_callbacks/main.c
@@ -10,6 +10,7 @@
 #include <rte_cycles.h>
 #include <rte_lcore.h>
 #include <rte_mbuf.h>
+#include <rte_mbuf_dyn.h>
 
 #define RX_RING_SIZE 1024
 #define TX_RING_SIZE 1024
@@ -18,6 +19,10 @@
 #define MBUF_CACHE_SIZE 250
 #define BURST_SIZE 32
 
+static int timestamp_dynfield_offset;
+#define TIMESTAMP_FIELD(mbuf) \
+       (*RTE_MBUF_DYNFIELD(mbuf, timestamp_dynfield_offset, uint64_t *))
+
 static const char usage[] =
        "%s EAL_ARGS -- [-t]\n";
 
@@ -47,7 +52,7 @@ add_timestamps(uint16_t port __rte_unused, uint16_t qidx 
__rte_unused,
        uint64_t now = rte_rdtsc();
 
        for (i = 0; i < nb_pkts; i++)
-               pkts[i]->udata64 = now;
+               TIMESTAMP_FIELD(pkts[i]) = now;
        return nb_pkts;
 }
 
@@ -65,7 +70,7 @@ calc_latency(uint16_t port, uint16_t qidx __rte_unused,
                rte_eth_read_clock(port, &ticks);
 
        for (i = 0; i < nb_pkts; i++) {
-               cycles += now - pkts[i]->udata64;
+               cycles += now - TIMESTAMP_FIELD(pkts[i]);
                if (hw_timestamping)
                        queue_ticks += ticks - pkts[i]->timestamp;
        }
@@ -261,6 +266,11 @@ main(int argc, char *argv[])
        };
        int opt, option_index;
 
+       static const struct rte_mbuf_dynfield timestamp_dynfield_desc = {
+               .name = RTE_MBUF_DYNFIELD_TIMESTAMP_NAME,
+               .size = sizeof(uint64_t),
+               .align = __alignof__(uint64_t),
+       };
 
        /* init EAL */
        int ret = rte_eal_init(argc, argv);
@@ -292,6 +302,11 @@ main(int argc, char *argv[])
        if (mbuf_pool == NULL)
                rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
 
+       timestamp_dynfield_offset =
+               rte_mbuf_dynfield_register(&timestamp_dynfield_desc);
+       if (timestamp_dynfield_offset < 0)
+               rte_exit(EXIT_FAILURE, "Cannot register mbuf field\n");
+
        /* initialize all ports */
        RTE_ETH_FOREACH_DEV(portid)
                if (port_init(portid, mbuf_pool) != 0)
-- 
2.28.0