trace_stat: Fix missing entry in stat file

One entry is missing in the output of a stat file.

The cause is, when stat_seq_start() is called the 2nd time, we
should start from the (pos-1)th elem in the rbtree but not pos,
because pos == 0 is the header.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4A891A65.70009@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Li Zefan 2009-08-17 16:52:53 +08:00 committed by Ingo Molnar
parent ba8b3a40ba
commit 97d53202a5

View file

@ -203,17 +203,21 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos)
{
struct stat_session *session = s->private;
struct rb_node *node;
int n = *pos;
int i;
/* Prevent from tracer switch or rbtree modification */
mutex_lock(&session->stat_mutex);
/* If we are in the beginning of the file, print the headers */
if (!*pos && session->ts->stat_headers)
return SEQ_START_TOKEN;
if (session->ts->stat_headers) {
if (n == 0)
return SEQ_START_TOKEN;
n--;
}
node = rb_first(&session->stat_root);
for (i = 0; node && i < *pos; i++)
for (i = 0; node && i < n; i++)
node = rb_next(node);
return node;