Add ftrace support
authorMichal Sojka <sojkam1@fel.cvut.cz>
Fri, 3 Dec 2010 16:13:47 +0000 (17:13 +0100)
committerMichal Sojka <sojkam1@fel.cvut.cz>
Fri, 3 Dec 2010 16:13:47 +0000 (17:13 +0100)
latester/latester.c

index f418567..9f0a466 100644 (file)
@@ -35,6 +35,8 @@
 
 #include "histogram.h"
 
+//#define FTRACE
+
 #ifndef DEBUG
 #define dbg(level, fmt, arg...) do {} while (0)
 #else
@@ -278,6 +280,42 @@ static inline get_tstamp(struct timespec *ts)
        clock_gettime(CLOCK_REALTIME, ts);
 }
 
+
+int trace_fd = -1;
+int marker_fd = -1;
+
+int init_ftrace()
+{
+#ifdef FTRACE
+       char *debugfs;
+       char path[256];
+       FILE *f;
+       
+       debugfs = "/sys/kernel/debug";
+       if (debugfs) {
+               strcpy(path, debugfs);
+               strcat(path,"/tracing/tracing_on");
+               trace_fd = open(path, O_WRONLY);
+               if (trace_fd >= 0)
+                       write(trace_fd, "1", 1);
+
+               strcpy(path, debugfs);
+               strcat(path,"/tracing/trace_marker");
+               marker_fd = open(path, O_WRONLY);
+
+               strcpy(path, debugfs);
+               strcat(path,"/tracing/set_ftrace_pid");
+               f = fopen(path, "w");
+               fprintf(f, "%d\n", getpid());
+               fclose(f);
+               system("echo function_graph > /sys/kernel/debug/tracing/current_tracer");
+               system("echo can_send > /sys/kernel/debug/tracing/set_graph_function");
+               system("echo > /sys/kernel/debug/tracing/trace");
+               system("echo 1 > /sys/kernel/debug/tracing/tracing_enabled");
+       }
+#endif /* FTRACE */
+}
+
 int send_frame(int socket)
 {
        struct can_frame frame;
@@ -311,7 +349,17 @@ int send_frame(int socket)
        mi->length = frame.can_dlc;
        get_tstamp(&mi->ts_sent);
        mi->sent = frame;
+       
+       if (trace_fd >= 0)
+               write(trace_fd, "1", 1);
        ret = write(socket, &frame, sizeof(frame));
+       if (marker_fd >= 0) {
+               char marker[100];
+               sprintf(marker, "write returned %d\n", ret);
+               write(marker_fd, marker, strlen(marker));
+       }
+       if (trace_fd >= 0)
+               write(trace_fd, "0", 1);
        return ret;
 }
 
@@ -627,6 +675,8 @@ int main(int argc, const char *argv[])
        ret = fcntl(completion_pipe[1], F_SETFL, O_NONBLOCK);
        if (ret == -1)
                error(1, errno, "pipe fcntl");
+
+       init_ftrace();
        
        pthread_create(&thread, 0, measure_thread, NULL);