trace: implement registration payload

The trace function payloads such as rte_trace_point_emit_* have
dual functions. The first to emit the payload for the registration
function and the second one to act as trace memory emitters.

When it is used as registration payload, it will do the following to
fulfill the registration job.
- Find out the size of the event,
- Generate metadata field string using __rte_trace_point_emit_field().

Signed-off-by: Jerin Jacob <jerinj@marvell.com>
Signed-off-by: Sunil Kumar Kori <skori@marvell.com>
Acked-by: David Marchand <david.marchand@redhat.com>

diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
index e82bb9e..da269de 100644 (file)
--- a/lib/librte_eal/common/eal_common_trace.c
+++ b/lib/librte_eal/common/eal_common_trace.c
@@ -378,6 +378,25 @@ trace_mem_per_thread_free(void)
        rte_spinlock_unlock(&trace->lock);
 }
 
+void
+__rte_trace_point_emit_field(size_t sz, const char *in, const char *datatype)
+{
+       char *field = RTE_PER_LCORE(ctf_field);
+       int count = RTE_PER_LCORE(ctf_count);
+       size_t size;
+       int rc;
+
+       size = RTE_MAX(0, TRACE_CTF_FIELD_SIZE - 1 - count);
+       RTE_PER_LCORE(trace_point_sz) += sz;
+       rc = snprintf(RTE_PTR_ADD(field, count), size, "%s %s;", datatype, in);
+       if (rc <= 0 || (size_t)rc >= size) {
+               RTE_PER_LCORE(trace_point_sz) = 0;
+               trace_crit("CTF field is too long");
+               return;
+       }
+       RTE_PER_LCORE(ctf_count) += rc;
+}
+
 int
 __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
                void (*register_fn)(void))

diff --git a/lib/librte_eal/include/rte_trace_point.h b/lib/librte_eal/include/rte_trace_point.h
index fc3d9c4..34dcba3 100644 (file)
--- a/lib/librte_eal/include/rte_trace_point.h
+++ b/lib/librte_eal/include/rte_trace_point.h
@@ -236,6 +236,25 @@ __rte_trace_point_fp_is_enabled(void)
 __rte_experimental
 void __rte_trace_mem_per_thread_alloc(void);
 
+/**
+ * @internal
+ *
+ * Helper function to emit field.
+ *
+ * @param sz
+ *   The tracepoint size.
+ * @param field
+ *   The name of the trace event.
+ * @param type
+ *   The datatype of the trace event as string.
+ * @return
+ *   - 0: Success.
+ *   - <0: Failure.
+ */
+__rte_experimental
+void __rte_trace_point_emit_field(size_t sz, const char *field,
+       const char *type);
+
 /**
  * @internal
  *

diff --git a/lib/librte_eal/include/rte_trace_point_register.h b/lib/librte_eal/include/rte_trace_point_register.h
index 6c5872a..4e2306f 100644 (file)
--- a/lib/librte_eal/include/rte_trace_point_register.h
+++ b/lib/librte_eal/include/rte_trace_point_register.h
@@ -17,4 +17,24 @@ RTE_DECLARE_PER_LCORE(volatile int, trace_point_sz);
        __rte_trace_point_register(&__##trace, RTE_STR(name), \
                (void (*)(void)) trace)
 
+#define __rte_trace_point_emit_header_generic(t) \
+       RTE_PER_LCORE(trace_point_sz) = __RTE_TRACE_EVENT_HEADER_SZ
+
+#define __rte_trace_point_emit_header_fp(t) \
+       __rte_trace_point_emit_header_generic(t)
+
+#define __rte_trace_point_emit(in, type) \
+do { \
+       RTE_BUILD_BUG_ON(sizeof(type) != sizeof(typeof(in))); \
+       __rte_trace_point_emit_field(sizeof(type), RTE_STR(in), \
+               RTE_STR(type)); \
+} while (0)
+
+#define rte_trace_point_emit_string(in) \
+do { \
+       RTE_SET_USED(in); \
+       __rte_trace_point_emit_field(__RTE_TRACE_EMIT_STRING_LEN_MAX, \
+               RTE_STR(in)"[32]", "string_bounded_t"); \
+} while (0)
+
 #endif /* _RTE_TRACE_POINT_REGISTER_H_ */

diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
index b4b3a92..8b51c8a 100644 (file)
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -338,6 +338,7 @@ EXPERIMENTAL {
 
        # added in 20.05
        __rte_trace_mem_per_thread_alloc;
+       __rte_trace_point_emit_field;
        __rte_trace_point_register;
        per_lcore_trace_mem;
        per_lcore_trace_point_sz;