trace: implement register API

[dpdk.git] / lib / librte_eal / common / eal_common_trace.c

diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
index 33a6e56..966bcf0 100644 (file)
--- a/lib/librte_eal/common/eal_common_trace.c
+++ b/lib/librte_eal/common/eal_common_trace.c
@@ -2,6 +2,107 @@
  * Copyright(C) 2020 Marvell International Ltd.
  */
 
-#include <rte_trace.h>
-#include <rte_trace_point.h>
+#include <inttypes.h>
+#include <sys/queue.h>
 
+#include <rte_common.h>
+#include <rte_errno.h>
+#include <rte_lcore.h>
+#include <rte_per_lcore.h>
+#include <rte_string_fns.h>
+
+#include "eal_trace.h"
+
+RTE_DEFINE_PER_LCORE(volatile int, trace_point_sz);
+static RTE_DEFINE_PER_LCORE(char, ctf_field[TRACE_CTF_FIELD_SIZE]);
+static RTE_DEFINE_PER_LCORE(int, ctf_count);
+
+static struct trace_point_head tp_list = STAILQ_HEAD_INITIALIZER(tp_list);
+static struct trace trace;
+
+int
+__rte_trace_point_register(rte_trace_point_t *handle, const char *name,
+               void (*register_fn)(void))
+{
+       char *field = RTE_PER_LCORE(ctf_field);
+       struct trace_point *tp;
+       uint16_t sz;
+
+       /* Sanity checks of arguments */
+       if (name == NULL || register_fn == NULL || handle == NULL) {
+               trace_err("invalid arguments");
+               rte_errno = EINVAL;
+               goto fail;
+       }
+
+       /* Check the size of the trace point object */
+       RTE_PER_LCORE(trace_point_sz) = 0;
+       RTE_PER_LCORE(ctf_count) = 0;
+       register_fn();
+       if (RTE_PER_LCORE(trace_point_sz) == 0) {
+               trace_err("missing rte_trace_emit_header() in register fn");
+               rte_errno = EBADF;
+               goto fail;
+       }
+
+       /* Is size overflowed */
+       if (RTE_PER_LCORE(trace_point_sz) > UINT16_MAX) {
+               trace_err("trace point size overflowed");
+               rte_errno = ENOSPC;
+               goto fail;
+       }
+
+       /* Are we running out of space to store trace points? */
+       if (trace.nb_trace_points > UINT16_MAX) {
+               trace_err("trace point exceeds the max count");
+               rte_errno = ENOSPC;
+               goto fail;
+       }
+
+       /* Get the size of the trace point */
+       sz = RTE_PER_LCORE(trace_point_sz);
+       tp = calloc(1, sizeof(struct trace_point));
+       if (tp == NULL) {
+               trace_err("fail to allocate trace point memory");
+               rte_errno = ENOMEM;
+               goto fail;
+       }
+
+       /* Initialize the trace point */
+       if (rte_strscpy(tp->name, name, TRACE_POINT_NAME_SIZE) < 0) {
+               trace_err("name is too long");
+               rte_errno = E2BIG;
+               goto free;
+       }
+
+       /* Copy the field data for future use */
+       if (rte_strscpy(tp->ctf_field, field, TRACE_CTF_FIELD_SIZE) < 0) {
+               trace_err("CTF field size is too long");
+               rte_errno = E2BIG;
+               goto free;
+       }
+
+       /* Clear field memory for the next event */
+       memset(field, 0, TRACE_CTF_FIELD_SIZE);
+
+       /* Form the trace handle */
+       *handle = sz;
+       *handle |= trace.nb_trace_points << __RTE_TRACE_FIELD_ID_SHIFT;
+
+       trace.nb_trace_points++;
+       tp->handle = handle;
+
+       /* Add the trace point at tail */
+       STAILQ_INSERT_TAIL(&tp_list, tp, next);
+       __atomic_thread_fence(__ATOMIC_RELEASE);
+
+       /* All Good !!! */
+       return 0;
+free:
+       free(tp);
+fail:
+       if (trace.register_errno == 0)
+               trace.register_errno = rte_errno;
+
+       return -rte_errno;
+}