trace: implement operation APIs

This patch implements the following public trace APIs.

- rte_trace_is_enabled()
- rte_trace_mode_get()
- rte_trace_mode_set()
- rte_trace_pattern()
- rte_trace_point_disable()
- rte_trace_point_enable()
- rte_trace_point_is_enabled()
- rte_trace_point_lookup()
- rte_trace_regexp()

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>

lib/librte_eal/common/eal_common_trace.c

@@ -2,8 +2,10 @@
  * Copyright(C) 2020 Marvell International Ltd.
  */
 
+#include <fnmatch.h>
 #include <inttypes.h>
 #include <sys/queue.h>
+#include <regex.h>
 
 #include <rte_common.h>
 #include <rte_errno.h>
@@ -20,6 +22,145 @@ static RTE_DEFINE_PER_LCORE(int, ctf_count);
 static struct trace_point_head tp_list = STAILQ_HEAD_INITIALIZER(tp_list);
 static struct trace trace;
 
+bool
+rte_trace_is_enabled(void)
+{
+	return trace.status;
+}
+
+static void
+trace_mode_set(rte_trace_point_t *trace, enum rte_trace_mode mode)
+{
+	if (mode == RTE_TRACE_MODE_OVERWRITE)
+		__atomic_and_fetch(trace, ~__RTE_TRACE_FIELD_ENABLE_DISCARD,
+			__ATOMIC_RELEASE);
+	else
+		__atomic_or_fetch(trace, __RTE_TRACE_FIELD_ENABLE_DISCARD,
+			__ATOMIC_RELEASE);
+}
+
+void
+rte_trace_mode_set(enum rte_trace_mode mode)
+{
+	struct trace_point *tp;
+
+	if (!rte_trace_is_enabled())
+		return;
+
+	STAILQ_FOREACH(tp, &tp_list, next)
+		trace_mode_set(tp->handle, mode);
+
+	trace.mode = mode;
+}
+
+enum
+rte_trace_mode rte_trace_mode_get(void)
+{
+	return trace.mode;
+}
+
+static bool
+trace_point_is_invalid(rte_trace_point_t *t)
+{
+	return (t == NULL) || (trace_id_get(t) >= trace.nb_trace_points);
+}
+
+bool
+rte_trace_point_is_enabled(rte_trace_point_t *trace)
+{
+	uint64_t val;
+
+	if (trace_point_is_invalid(trace))
+		return false;
+
+	val = __atomic_load_n(trace, __ATOMIC_ACQUIRE);
+	return (val & __RTE_TRACE_FIELD_ENABLE_MASK) != 0;
+}
+
+int
+rte_trace_point_enable(rte_trace_point_t *trace)
+{
+	if (trace_point_is_invalid(trace))
+		return -ERANGE;
+
+	__atomic_or_fetch(trace, __RTE_TRACE_FIELD_ENABLE_MASK,
+		__ATOMIC_RELEASE);
+	return 0;
+}
+
+int
+rte_trace_point_disable(rte_trace_point_t *trace)
+{
+	if (trace_point_is_invalid(trace))
+		return -ERANGE;
+
+	__atomic_and_fetch(trace, ~__RTE_TRACE_FIELD_ENABLE_MASK,
+		__ATOMIC_RELEASE);
+	return 0;
+}
+
+int
+rte_trace_pattern(const char *pattern, bool enable)
+{
+	struct trace_point *tp;
+	int rc = 0, found = 0;
+
+	STAILQ_FOREACH(tp, &tp_list, next) {
+		if (fnmatch(pattern, tp->name, 0) == 0) {
+			if (enable)
+				rc = rte_trace_point_enable(tp->handle);
+			else
+				rc = rte_trace_point_disable(tp->handle);
+			found = 1;
+		}
+		if (rc < 0)
+			return rc;
+	}
+
+	return rc | found;
+}
+
+int
+rte_trace_regexp(const char *regex, bool enable)
+{
+	struct trace_point *tp;
+	int rc = 0, found = 0;
+	regex_t r;
+
+	if (regcomp(&r, regex, 0) != 0)
+		return -EINVAL;
+
+	STAILQ_FOREACH(tp, &tp_list, next) {
+		if (regexec(&r, tp->name, 0, NULL, 0) == 0) {
+			if (enable)
+				rc = rte_trace_point_enable(tp->handle);
+			else
+				rc = rte_trace_point_disable(tp->handle);
+			found = 1;
+		}
+		if (rc < 0)
+			return rc;
+	}
+	regfree(&r);
+
+	return rc | found;
+}
+
+rte_trace_point_t *
+rte_trace_point_lookup(const char *name)
+{
+	struct trace_point *tp;
+
+	if (name == NULL)
+		return NULL;
+
+	STAILQ_FOREACH(tp, &tp_list, next)
+		if (strncmp(tp->name, name, TRACE_POINT_NAME_SIZE) == 0)
+			return tp->handle;
+
+	return NULL;
+}
+
 int
 __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
 		void (*register_fn)(void))

lib/librte_eal/common/eal_trace.h

@@ -26,9 +26,19 @@ struct trace_point {
 
 struct trace {
 	int register_errno;
+	bool status;
+	enum rte_trace_mode mode;
 	uint32_t nb_trace_points;
 };
 
+/* Helper functions */
+static inline uint16_t
+trace_id_get(rte_trace_point_t *trace)
+{
+	return (*trace & __RTE_TRACE_FIELD_ID_MASK) >>
+		__RTE_TRACE_FIELD_ID_SHIFT;
+}
+
 /* Trace point list functions */
 STAILQ_HEAD(trace_point_head, trace_point);
 

lib/librte_eal/rte_eal_version.map

@@ -341,4 +341,13 @@ EXPERIMENTAL {
 	per_lcore_trace_point_sz;
 	rte_log_can_log;
 	rte_thread_getname;
+	rte_trace_is_enabled;
+	rte_trace_mode_get;
+	rte_trace_mode_set;
+	rte_trace_pattern;
+	rte_trace_point_disable;
+	rte_trace_point_enable;
+	rte_trace_point_is_enabled;
+	rte_trace_point_lookup;
+	rte_trace_regexp;
 };