tracing: Fix set_ftrace_filter probe function display

If one or more function probes (like traceon) are enabled,
and there's no other function filter, the first probe
func is skipped (which one depends on the position in the hash).

$ echo sys_open:traceon sys_close:traceon > ./set_ftrace_filter
$ cat set_ftrace_filter
#### all functions enabled ####
sys_close:traceon:unlimited
$

The reason was, that in the case of no other function filter,
the func_pos was not properly updated before calling t_hash_start.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1297874134-7008-1-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 888b611897d3737fddb0c890084cacfbe2a359b3..c075f4ea6b94f1c9772915b064082341d843e9d5 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1467,7 +1467,7 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
                return t_hash_next(m, pos);
 
        (*pos)++;
-       iter->pos = *pos;
+       iter->pos = iter->func_pos = *pos;
 
        if (iter->flags & FTRACE_ITER_PRINTALL)
                return t_hash_start(m, pos);
@@ -1502,7 +1502,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
        if (!rec)
                return t_hash_start(m, pos);
 
-       iter->func_pos = *pos;
        iter->func = rec;
 
        return iter;