tracing/ftrace: fix a memory leak in stat tracing

Impact: fix memory leak

This patch fixes a memory leak inside reset_stat_list(). The freeing
loop iterated only once.

Also turn the stat_list into a simple struct list_head, which
simplify the code and avoid an unused static pointer.

Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Frederic Weisbecker 2009-01-06 21:33:30 +01:00 committed by Ingo Molnar
parent 431aa3fbf5
commit ff288b274a

View File

@ -21,7 +21,7 @@ struct trace_stat_list {
void *stat;
};
static struct trace_stat_list stat_list;
static LIST_HEAD(stat_list);
/*
* This is a copy of the current tracer to avoid racy
@ -39,22 +39,12 @@ static DEFINE_MUTEX(stat_list_mutex);
static void reset_stat_list(void)
{
struct trace_stat_list *node;
struct list_head *next;
struct trace_stat_list *node, *next;
if (list_empty(&stat_list.list))
return;
node = list_entry(stat_list.list.next, struct trace_stat_list, list);
next = node->list.next;
while (&node->list != next) {
kfree(node);
node = list_entry(next, struct trace_stat_list, list);
}
list_for_each_entry_safe(node, next, &stat_list, list)
kfree(node);
INIT_LIST_HEAD(&stat_list.list);
INIT_LIST_HEAD(&stat_list);
}
void init_tracer_stat(struct tracer *trace)
@ -107,7 +97,7 @@ static int stat_seq_init(void)
}
INIT_LIST_HEAD(&new_entry->list);
list_add(&new_entry->list, &stat_list.list);
list_add(&new_entry->list, &stat_list);
new_entry->stat = current_tracer.stat_start();
prev_stat = new_entry->stat;
@ -130,7 +120,7 @@ static int stat_seq_init(void)
if (!new_entry->stat)
break;
list_for_each_entry(iter_entry, &stat_list.list, list) {
list_for_each_entry(iter_entry, &stat_list, list) {
/* Insertion with a descendent sorting */
if (current_tracer.stat_cmp(new_entry->stat,
iter_entry->stat) > 0) {
@ -141,7 +131,7 @@ static int stat_seq_init(void)
/* The current smaller value */
} else if (list_is_last(&iter_entry->list,
&stat_list.list)) {
&stat_list)) {
list_add(&new_entry->list, &iter_entry->list);
break;
}
@ -162,7 +152,7 @@ static int stat_seq_init(void)
static void *stat_seq_start(struct seq_file *s, loff_t *pos)
{
struct trace_stat_list *l = (struct trace_stat_list *)s->private;
struct list_head *l = (struct list_head *)s->private;
/* Prevent from tracer switch or stat_list modification */
mutex_lock(&stat_list_mutex);
@ -171,14 +161,14 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos)
if (!*pos && current_tracer.stat_headers)
current_tracer.stat_headers(s);
return seq_list_start(&l->list, *pos);
return seq_list_start(l, *pos);
}
static void *stat_seq_next(struct seq_file *s, void *p, loff_t *pos)
{
struct trace_stat_list *l = (struct trace_stat_list *)s->private;
struct list_head *l = (struct list_head *)s->private;
return seq_list_next(p, &l->list, pos);
return seq_list_next(p, l, pos);
}
static void stat_seq_stop(struct seq_file *m, void *p)
@ -188,8 +178,10 @@ static void stat_seq_stop(struct seq_file *m, void *p)
static int stat_seq_show(struct seq_file *s, void *v)
{
struct trace_stat_list *l = list_entry(v, struct trace_stat_list, list);
return current_tracer.stat_show(s, l->stat);
struct trace_stat_list *entry =
list_entry(v, struct trace_stat_list, list);
return current_tracer.stat_show(s, entry->stat);
}
static const struct seq_operations trace_stat_seq_ops = {
@ -237,7 +229,6 @@ static int __init tracing_stat_init(void)
struct dentry *d_tracing;
struct dentry *entry;
INIT_LIST_HEAD(&stat_list.list);
d_tracing = tracing_init_dentry();
entry = debugfs_create_file("trace_stat", 0444, d_tracing,