Messages in this thread Patch in this message | | | Subject | Re: [BUG] ftrace: available_filter_functions empty after unloading module | From | Steven Rostedt <> | Date | Thu, 13 Dec 2012 12:08:05 -0500 |
| |
On Thu, 2012-12-13 at 08:34 -0500, Steven Rostedt wrote: > On Mon, 2012-12-10 at 12:45 +0100, Piotr Haber wrote: > > > > So you unloaded a module that you were tracing, correct? Hmm, the > > > warning that you hit was an accounting error. The accounting of what > > > functions are traced and what isn't. For some reason it tried to disable > > > a function that wasn't being traced. > > Yes, it happens when i unload a module that i traced before > > > > > Can you easily reproduce this? If so, can you give my your .config and > > > the steps you used to trigger it. > > Not 100% but it happens often enough to be annoying > > Attached is the config > > As for reproduction, i load the brcmsmac module, add all it symbols to > > set_ftrace_filter, associate with AP and unload the module > > nothing fancy, i use 'function' tracer > > Thanks, I'll see if I can reproduce it. >
I'm having trouble reproducing. Can you apply the below patch and try to reproduce it. And then show me the contents of /debug/tracing/enabled_functions.
Thanks,
-- Steve
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 4451aa3..e069227 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -2390,9 +2390,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos) struct ftrace_ops *ops = iter->ops; struct dyn_ftrace *rec = NULL; - if (unlikely(ftrace_disabled)) - return NULL; - if (iter->flags & FTRACE_ITER_HASH) return t_hash_next(m, pos); @@ -2449,9 +2446,6 @@ static void *t_start(struct seq_file *m, loff_t *pos) mutex_lock(&ftrace_lock); - if (unlikely(ftrace_disabled)) - return NULL; - /* * If an lseek was done, then reset and start from beginning. */ @@ -2557,9 +2551,6 @@ ftrace_enabled_open(struct inode *inode, struct file *file) { struct ftrace_iterator *iter; - if (unlikely(ftrace_disabled)) - return -ENODEV; - iter = __seq_open_private(file, &show_ftrace_seq_ops, sizeof(*iter)); if (iter) { iter->pg = ftrace_pages_start;
| |