1 files changed, 97 insertions, 13 deletions

diff --git a/trace-cmd.c b/trace-cmd.c
index 5e394a6..75bc325 100644
--- a/trace-cmd.c
+++ b/trace-cmd.c
@@ -57,6 +57,8 @@ static int sleep_time = 1000;
 static int cpu_count;
 static int *pids;
 
+static int filter_task;
+
 struct event_list {
         struct event_list *next;
         const char *event;
@@ -229,6 +231,65 @@ static int set_ftrace(int set)
         return 0;
 }
 
+static char *get_tracing_file(const char *name);
+static void put_tracing_file(char *file);
+
+static void clear_trace(void)
+{
+        FILE *fp;
+        char *path;
+
+        /* reset the trace */
+        path = get_tracing_file("trace");
+        fp = fopen(path, "w");
+        if (!fp)
+                die("writing to '%s'", path);
+        put_tracing_file(path);
+        fwrite("0", 1, 1, fp);
+        fclose(fp);
+}
+
+static void update_ftrace_pid(const char *pid)
+{
+        char *path;
+        int fd;
+
+        path = get_tracing_file("set_ftrace_pid");
+        if (!path)
+                return;
+
+        fd = open(path, O_WRONLY);
+        if (fd < 0)
+                return;
+
+        if (write(fd, pid, strlen(pid)) < 0)
+                die("error writing to %s", path);
+
+        close(fd);
+}
+
+static void update_pid_event_filters(char *pid);
+
+static void update_task_filter(void)
+{
+        int pid = getpid();
+        char spid[100];
+
+        if (!filter_task) {
+                update_ftrace_pid("");
+                return;
+        }
+
+        snprintf(spid, 100, "%d", pid);
+
+        update_ftrace_pid(spid);
+
+        update_pid_event_filters(spid);
+
+        /* clear the trace */
+
+}
+
 void run_cmd(int argc, char **argv)
 {
         int status;
@@ -238,6 +299,7 @@ void run_cmd(int argc, char **argv)
                 die("failed to fork");
         if (!pid) {
                 /* child */
+                update_task_filter();
                 if (execvp(argv[0], argv))
                         exit(-1);
         }
@@ -664,22 +726,12 @@ static void disable_tracing(void)
 
 static void disable_all(void)
 {
-        FILE *fp;
-        char *path;
-
         disable_tracing();
 
         set_plugin("nop");
         disable_event("all");
 
-        /* reset the trace */
-        path = get_tracing_file("trace");
-        fp = fopen(path, "w");
-        if (!fp)
-                die("writing to '%s'", path);
-        put_tracing_file(path);
-        fwrite("0", 1, 1, fp);
-        fclose(fp);
+        clear_trace();
 }
 
 static void reset_max_latency(void)
@@ -697,6 +749,33 @@ static void reset_max_latency(void)
         fclose(fp);
 }
 
+static void update_pid_event_filters(char *pid)
+{
+        struct event_list *event;
+        char *filter;
+
+        filter = malloc_or_die(strlen(pid) + strlen("(common_pid==)") + 1);
+        sprintf(filter, "(common_pid==%s)", pid);
+
+        for (event = event_selection; event; event = event->next) {
+                if (!event->neg) {
+                        if (event->filter) {
+                                event->filter =
+                                        realloc(event->filter,
+                                                strlen(event->filter) +
+                                                strlen("&&") +
+                                                strlen(filter) + 1);
+                                        strcat(event->filter, "&&");
+                                        strcat(event->filter, filter);
+                        } else
+                                event->filter = strdup(filter);
+                        enable_event(event->event, event->filter);
+                }
+        }
+
+        free(filter);
+}
+
 static void enable_events(void)
 {
         struct event_list *event;
@@ -889,10 +968,11 @@ void usage(char **argv)
         printf("\n"
                "%s version %s\n\n"
                "usage:\n"
-               " %s record [-v][-e event [-f filter]][-p plugin][-d][-o file][-s usecs][-O option ] [command ...]\n"
+               " %s record [-v][-e event [-f filter]][-p plugin][-F][-d][-o file][-s usecs][-O option ] [command ...]\n"
                "          -e run command with event enabled\n"
                "          -f filter for previous -e event\n"
                "          -p run command with plugin enabled\n"
+               "          -F filter only on the given process\n"
                "          -v will negate all -e after it (disable those events)\n"
                "          -d disable function tracer when running\n"
                "          -o data output file [default trace.dat]\n"
@@ -981,7 +1061,7 @@ int main (int argc, char **argv)
                    (strcmp(argv[1], "start") == 0) ||
                    ((extract = strcmp(argv[1], "extract") == 0))) {
 
-                while ((c = getopt(argc-1, argv+1, "+he:f:p:do:O:s:v")) >= 0) {
+                while ((c = getopt(argc-1, argv+1, "+he:f:Fp:do:O:s:v")) >= 0) {
                         switch (c) {
                         case 'h':
                                 usage(argv);
@@ -1018,6 +1098,9 @@ int main (int argc, char **argv)
                                 }
                                 break;
 
+                        case 'F':
+                                filter_task = 1;
+                                break;
                         case 'v':
                                 if (extract)
                                         usage(argv);
@@ -1173,6 +1256,7 @@ int main (int argc, char **argv)
                 if (run_command)
                         run_cmd((argc - optind) - 1, &argv[optind + 1]);
                 else {
+                        update_task_filter();
                         /* sleep till we are woken with Ctrl^C */
                         printf("Hit Ctrl^C to stop recording\n");
                         while (!finished)