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Diffstat (limited to 'kernel/trace/trace_events.c')
-rw-r--r--kernel/trace/trace_events.c56
1 files changed, 18 insertions, 38 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 56c260b83a9..d128f65778e 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -232,10 +232,9 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_parser parser;
- size_t read = 0;
- ssize_t ret;
+ ssize_t read, ret;
- if (!cnt || cnt < 0)
+ if (!cnt)
return 0;
ret = tracing_update_buffers();
@@ -247,7 +246,7 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
read = trace_get_user(&parser, ubuf, cnt, ppos);
- if (trace_parser_loaded((&parser))) {
+ if (read >= 0 && trace_parser_loaded((&parser))) {
int set = 1;
if (*parser.buffer == '!')
@@ -271,42 +270,32 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
static void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct list_head *list = m->private;
- struct ftrace_event_call *call;
+ struct ftrace_event_call *call = v;
(*pos)++;
- for (;;) {
- if (list == &ftrace_events)
- return NULL;
-
- call = list_entry(list, struct ftrace_event_call, list);
-
+ list_for_each_entry_continue(call, &ftrace_events, list) {
/*
* The ftrace subsystem is for showing formats only.
* They can not be enabled or disabled via the event files.
*/
if (call->regfunc)
- break;
-
- list = list->next;
+ return call;
}
- m->private = list->next;
-
- return call;
+ return NULL;
}
static void *t_start(struct seq_file *m, loff_t *pos)
{
- struct ftrace_event_call *call = NULL;
+ struct ftrace_event_call *call;
loff_t l;
mutex_lock(&event_mutex);
- m->private = ftrace_events.next;
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
for (l = 0; l <= *pos; ) {
- call = t_next(m, NULL, &l);
+ call = t_next(m, call, &l);
if (!call)
break;
}
@@ -316,37 +305,28 @@ static void *t_start(struct seq_file *m, loff_t *pos)
static void *
s_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct list_head *list = m->private;
- struct ftrace_event_call *call;
+ struct ftrace_event_call *call = v;
(*pos)++;
- retry:
- if (list == &ftrace_events)
- return NULL;
-
- call = list_entry(list, struct ftrace_event_call, list);
-
- if (!call->enabled) {
- list = list->next;
- goto retry;
+ list_for_each_entry_continue(call, &ftrace_events, list) {
+ if (call->enabled)
+ return call;
}
- m->private = list->next;
-
- return call;
+ return NULL;
}
static void *s_start(struct seq_file *m, loff_t *pos)
{
- struct ftrace_event_call *call = NULL;
+ struct ftrace_event_call *call;
loff_t l;
mutex_lock(&event_mutex);
- m->private = ftrace_events.next;
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
for (l = 0; l <= *pos; ) {
- call = s_next(m, NULL, &l);
+ call = s_next(m, call, &l);
if (!call)
break;
}