A new API is proposed, to get tep event describing given dynamic event:
tracefs_dynevent_get_event()
The API detects any newly created dynamic events, but does not detect
the deletion.
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@xxxxxxxxx>
---
Documentation/libtracefs-dynevents.txt | 14 +++++++++++--
include/tracefs.h | 2 ++
src/tracefs-dynevents.c | 29 ++++++++++++++++++++++++++
3 files changed, 43 insertions(+), 2 deletions(-)
diff --git a/Documentation/libtracefs-dynevents.txt b/Documentation/libtracefs-dynevents.txt
index a374651..7de06be 100644
--- a/Documentation/libtracefs-dynevents.txt
+++ b/Documentation/libtracefs-dynevents.txt
@@ -4,8 +4,8 @@ libtracefs(3)
NAME
----
tracefs_dynevent_create, tracefs_dynevent_destroy, tracefs_dynevent_destroy_all,
-tracefs_dynevent_free, tracefs_dynevent_list_free, tracefs_dynevent_get_all, tracefs_dynevent_info -
-Create, destroy, free and get dynamic events.
+tracefs_dynevent_free, tracefs_dynevent_list_free, tracefs_dynevent_get_all, tracefs_dynevent_info,
+tracefs_dynevent_get_event - Create, destroy, free and get dynamic events.
SYNOPSIS
--------
@@ -23,6 +23,7 @@ void *tracefs_dynevent_list_free*(struct tracefs_dynevent pass:[*]pass:[*]_event
struct tracefs_dynevent pass:[*]*tracefs_dynevent_get*(enum tracefs_dynevent_type _type_, const char pass:[*]_system_, const char pass:[*]_event_);
struct tracefs_dynevent pass:[*]pass:[*]*tracefs_dynevent_get_all*(unsigned int _types_, const char pass:[*]_system_);
enum tracefs_dynevent_type *tracefs_dynevent_info*(struct tracefs_dynevent pass:[*]_dynevent_, char pass:[*]pass:[*]_system_, char pass:[*]pass:[*]_event_, char pass:[*]pass:[*]_prefix_, char pass:[*]pass:[*]_addr_, char pass:[*]pass:[*]_format_);
+struct tep_event pass:[*]*tracefs_dynevent_get_event*(struct tep_handle pass:[*]_tep_, struct tracefs_dynevent pass:[*]_dynevent_);
--
DESCRIPTION
@@ -68,6 +69,11 @@ if relevant for this event type. If _format_ is non NULL, it will hold the forma
dynamic event. Note, that the content in _group_, _event_, _prefix_, _addr_, and _format_ must be
freed with free(3) if they are set.
+The *tracefs_dynevent_get_event*() function returns tep event, describing the given dynamic event.
+If the dynamic event is newly created and not yet loaded in the @tep, the dynamic event system is
+rescanned for any new events. The returned pointer to tep event is controlled by @tep and must not
+be freed.
+
RETURN VALUE
------------
@@ -88,6 +94,10 @@ in case of an error or in case there are no events in the system. That array mus
on error. If _system_, _event_, _prefix_, _addr_, or _format_ are non NULL, they will contain
allocated strings that must be freed by free(3).
+The *tracefs_dynevent_get_event*() function returns pointer to tep event or NULL in case of an error
+or if the requested dynamic event is missing. The returned pointer to tep event is controlled by
+@tep and must not be freed.
+
ERRORS
------
The following errors are for all the above calls:
diff --git a/include/tracefs.h b/include/tracefs.h
index 9662603..fbd7d31 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -262,6 +262,8 @@ tracefs_dynevent_get(enum tracefs_dynevent_type type, const char *system, const
enum tracefs_dynevent_type
tracefs_dynevent_info(struct tracefs_dynevent *dynevent, char **system,
char **event, char **prefix, char **addr, char **format);
+struct tep_event *
+tracefs_dynevent_get_event(struct tep_handle *tep, struct tracefs_dynevent *dynevent);
struct tracefs_dynevent *
tracefs_eprobe_alloc(const char *system, const char *event,
diff --git a/src/tracefs-dynevents.c b/src/tracefs-dynevents.c
index ea07d13..2ff3c87 100644
--- a/src/tracefs-dynevents.c
+++ b/src/tracefs-dynevents.c
@@ -752,3 +752,32 @@ error:
return TRACEFS_DYNEVENT_UNKNOWN;
}
+
+/**
+ * tracefs_dynevent_get_event - return tep event, representing the given dynamic event
+ * @tep: a handle to the trace event parser context, that holds the events
+ * @dynevent: a dynamic event context, describing given dynamic event.
+ *
+ * Returns pointer to tep event, describing the given dynamic event. The pointer
+ * is managed by @tep handle and must not be freed. In case of an error, or in case
+ * the requested dynamic event is missing in the @tep handler - NULL is returned.
+ */
+struct tep_event *
+tracefs_dynevent_get_event(struct tep_handle *tep, struct tracefs_dynevent *dynevent)
+{
+ struct tep_event *event;
+
+ if (!tep || !dynevent || !dynevent->event)
+ return NULL;
+
+ /* If the dynamic event is already loaded in the tep, return it */
+ event = tep_find_event_by_name(tep, dynevent->system, dynevent->event);
+ if (event)
+ return event;
+
+ /* Try to load any new events from the given system */
+ if (trace_load_events(tep, NULL, dynevent->system))
+ return NULL;
+
+ return tep_find_event_by_name(tep, dynevent->system, dynevent->event);
+}
--
2.33.1
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