[PATCH v2 1/4] perf/trace: Add function to find event type by name

[Takao Indoh]

This patch adds function to find struct trace_event by event name like
"sched_switch" , and return its type so that Intel PT logger can enable
the trace event in kernel. Intel PT logger needs this because it needs
sched_switch tracing to collect side-band data.

Signed-off-by: Takao Indoh 
---
 include/linux/trace_events.h|2 ++
 kernel/trace/trace_event_perf.c |   22 ++
 2 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index ed27917..d3cae4b 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -616,6 +616,8 @@ perf_trace_buf_submit(void *raw_data, int size, int rctx, 
u64 addr,
 {
perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task);
 }
+
+int perf_trace_event_get_type_by_name(char *system, char *name);
 #endif
 
 #endif /* _LINUX_TRACE_EVENT_H */
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index abfc903..1a851d5 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -21,6 +21,28 @@ typedef typeof(unsigned long [PERF_MAX_TRACE_SIZE / 
sizeof(unsigned long)])
 /* Count the events in use (per event id, not per instance) */
 static int total_ref_count;
 
+int perf_trace_event_get_type_by_name(char *system, char *name)
+{
+   struct trace_event_call *tp_event;
+   int ret = 0;
+   /*
+* All type is larger than __TRACE_LAST_TYPE + 1. Therefore return zero
+* as a invalid type if not found.
+*/
+
+   mutex_lock(_mutex);
+   list_for_each_entry(tp_event, _events, list) {
+   if (!strcmp(tp_event->class->system, system) &&
+   !strcmp(trace_event_name(tp_event), name)) {
+   ret = tp_event->event.type;
+   break;
+   }
+   }
+   mutex_unlock(_mutex);
+
+   return ret;
+}
+
 static int perf_trace_event_perm(struct trace_event_call *tp_event,
 struct perf_event *p_event)
 {
-- 
1.7.1


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[PATCH v2 1/4] perf/trace: Add function to find event type by name

[Takao Indoh]

This patch adds function to find struct trace_event by event name like
"sched_switch" , and return its type so that Intel PT logger can enable
the trace event in kernel. Intel PT logger needs this because it needs
sched_switch tracing to collect side-band data.

Signed-off-by: Takao Indoh 
---
 include/linux/trace_events.h|2 ++
 kernel/trace/trace_event_perf.c |   22 ++
 2 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index ed27917..d3cae4b 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -616,6 +616,8 @@ perf_trace_buf_submit(void *raw_data, int size, int rctx, 
u64 addr,
 {
perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task);
 }
+
+int perf_trace_event_get_type_by_name(char *system, char *name);
 #endif
 
 #endif /* _LINUX_TRACE_EVENT_H */
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index abfc903..1a851d5 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -21,6 +21,28 @@ typedef typeof(unsigned long [PERF_MAX_TRACE_SIZE / 
sizeof(unsigned long)])
 /* Count the events in use (per event id, not per instance) */
 static int total_ref_count;
 
+int perf_trace_event_get_type_by_name(char *system, char *name)
+{
+   struct trace_event_call *tp_event;
+   int ret = 0;
+   /*
+* All type is larger than __TRACE_LAST_TYPE + 1. Therefore return zero
+* as a invalid type if not found.
+*/
+
+   mutex_lock(_mutex);
+   list_for_each_entry(tp_event, _events, list) {
+   if (!strcmp(tp_event->class->system, system) &&
+   !strcmp(trace_event_name(tp_event), name)) {
+   ret = tp_event->event.type;
+   break;
+   }
+   }
+   mutex_unlock(_mutex);
+
+   return ret;
+}
+
 static int perf_trace_event_perm(struct trace_event_call *tp_event,
 struct perf_event *p_event)
 {
-- 
1.7.1


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/