diff options
| -rw-r--r-- | kernel/trace/trace_events.c | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index fd16a254173c..e8c445d1f190 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -682,13 +682,23 @@ static ssize_t event_enable_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_file *file = filp->private_data; + struct ftrace_event_file *file; + unsigned long flags; char *buf; - if (file->flags & FTRACE_EVENT_FL_ENABLED) { - if (file->flags & FTRACE_EVENT_FL_SOFT_DISABLED) + mutex_lock(&event_mutex); + file = event_file_data(filp); + if (likely(file)) + flags = file->flags; + mutex_unlock(&event_mutex); + + if (!file) + return -ENODEV; + + if (flags & FTRACE_EVENT_FL_ENABLED) { + if (flags & FTRACE_EVENT_FL_SOFT_DISABLED) buf = "0*\n"; - else if (file->flags & FTRACE_EVENT_FL_SOFT_MODE) + else if (flags & FTRACE_EVENT_FL_SOFT_MODE) buf = "1*\n"; else buf = "1\n"; @@ -702,13 +712,10 @@ static ssize_t event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - struct ftrace_event_file *file = filp->private_data; + struct ftrace_event_file *file; unsigned long val; int ret; - if (!file) - return -EINVAL; - ret = kstrtoul_from_user(ubuf, cnt, 10, &val); if (ret) return ret; @@ -720,8 +727,11 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, switch (val) { case 0: case 1: + ret = -ENODEV; mutex_lock(&event_mutex); - ret = ftrace_event_enable_disable(file, val); + file = event_file_data(filp); + if (likely(file)) + ret = ftrace_event_enable_disable(file, val); mutex_unlock(&event_mutex); break; |