tracefs_set_tracer - set the tracer
tracefs_stop_tracer - clear the tracer
Signed-off-by: Sameeruddin shaik <sameeross1994@xxxxxxxxx>
diff --git a/include/tracefs.h b/include/tracefs.h
index 55ee867..47d3282 100644
--- a/include/tracefs.h
+++ b/include/tracefs.h
@@ -173,4 +173,26 @@ int tracefs_function_filter(struct tracefs_instance *instance, const char *filte
int tracefs_function_notrace(struct tracefs_instance *instance, const char *filter,
const char *module, unsigned int flags);
+/*
+ * Tracers
+ */
+enum tracefs_tracers {
+ TRACEFS_TRACER_NOP = 0,
+ TRACEFS_TRACER_FUNCTION,
+ TRACEFS_TRACER_FUNCTION_GRAPH,
+ TRACEFS_TRACER_IRQSOFF,
+ TRACEFS_TRACER_PREEMPTOFF,
+ TRACEFS_TRACER_PREEMPTIRQSOFF,
+ TRACEFS_TRACER_WAKEUP,
+ TRACEFS_TRACER_WAKEUP_RT,
+ TRACEFS_TRACER_WAKEUP_DL,
+ TRACEFS_TRACER_MMIOTRACE,
+ TRACEFS_TRACER_HWLAT,
+ TRACEFS_TRACER_BRANCH,
+ TRACEFS_TRACER_BLOCK,
+};
+
+int tracefs_set_tracer(struct tracefs_instance *instance, enum tracefs_tracers tracer);
+
+int tracefs_stop_tracer(struct tracefs_instance *instance);
#endif /* _TRACE_FS_H */
diff --git a/src/tracefs-tools.c b/src/tracefs-tools.c
index 6ef17f6..ceddeda 100644
--- a/src/tracefs-tools.c
+++ b/src/tracefs-tools.c
@@ -25,6 +25,7 @@ __hidden pthread_mutex_t toplevel_lock = PTHREAD_MUTEX_INITIALIZER;
#define TRACE_FILTER "set_ftrace_filter"
#define TRACE_NOTRACE "set_ftrace_notrace"
#define TRACE_FILTER_LIST "available_filter_functions"
+#define TRACER "current_tracer"
/* File descriptor for Top level set_ftrace_filter */
static int ftrace_filter_fd = -1;
@@ -910,3 +911,88 @@ int tracefs_function_notrace(struct tracefs_instance *instance, const char *filt
tracefs_put_tracing_file(filter_path);
return ret;
}
+
+int write_tracer(int fd, const char *tracer)
+{
+ int ret;
+
+ ret = write(fd, tracer, strlen(tracer));
+ if (ret < strlen(tracer))
+ return -1;
+ return ret;
+}
+
+/**
+* tracefs_set_tracer - fucntion to set the tracer
+* @instance: ftrace instance, can be NULL for top tracing instance
+* @tracer: Tracer that has to be set, which can be integer from 0 - 13
+* or and enum value
+*/
+
+int tracefs_set_tracer(struct tracefs_instance *instance, enum tracefs_tracers tracer)
+{
+ char *tracer_path;
+ int ret = -1;
+ int fd = -1;
+
+ tracer_path = tracefs_instance_get_file(instance, TRACER);
+ if (!tracer_path)
+ return -1;
+
+ fd = open(tracer_path, O_WRONLY);
+ if (fd < 0)
+ goto out;
+
+ switch(tracer) {
+ case 0:
+ ret = write_tracer(fd , "nop");
+ break;
+ case 1:
+ ret = write_tracer(fd, "function");
+ break;
+ case 2:
+ ret = write_tracer(fd, "function_graph");
+ break;
+ case 3:
+ ret = write_tracer(fd, "irqsoff");
+ break;
+ case 4:
+ ret = write_tracer(fd, "preemptoff");
+ break;
+ case 5:
+ ret = write_tracer(fd, "preemptirqsoff");
+ break;
+ case 6:
+ ret = write_tracer(fd, "wakeup");
+ break;
+ case 7:
+ ret = write_tracer(fd, "wakeup_rt");
+ break;
+ case 8:
+ ret = write_tracer(fd, "wakeup_dl");
+ break;
+ case 9:
+ ret = write_tracer(fd, "mmiotrace");
+ break;
+ case 10:
+ ret = write_tracer(fd, "hwlat");
+ break;
+ case 11:
+ ret = write_tracer(fd, "branch");
+ break;
+ case 12:
+ ret = write_tracer(fd, "blk");
+ break;
+ default:
+ ret = -1;
+ }
+
+ out:
+ tracefs_put_tracing_file(tracer_path);
+ return ret;
+}
+
+int tracefs_stop_tracer(struct tracefs_instance *instance)
+{
+ return tracefs_set_tracer(instance, TRACEFS_TRACER_NOP);
+}
--
2.7.4
|