Re: [PATCH] tracing: Add a way to filter function addresses to function names

[Zheng Yejian]

On 2022/12/20 02:21, Steven Rostedt wrote:
> On Mon, 19 Dec 2022 10:38:50 +0800
> Zheng Yejian <zhengyejian1@xxxxxxxxxx> wrote:
>
> > > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
> > > index 33e0b4f8ebe6..db6e2f399440 100644
> > > --- a/kernel/trace/trace_events.c
> > > +++ b/kernel/trace/trace_events.c
> > > @@ -2822,7 +2822,7 @@ static __init int setup_trace_triggers(char *str)
> > >    		if (!trigger)
> > >    			break;
> > >    		bootup_triggers[i].event = strsep(&trigger, ".");
> > > -		bootup_triggers[i].trigger = strsep(&trigger, ".");
> > > +		bootup_triggers[i].trigger = strsep(&trigger, "");
> >
> > Would it be better to change to:
> >
> >        bootup_triggers[i].trigger = trigger;
>
> Sure, I'll make the update.
>
> > Because there is unnecessary loop if call strsep(s, "") :-)
> >     strsep(s, ct) {
> >       strpbrk(cs, ct) {
> >         // when 'ct' is empty string, here will always return NULL
> >         // after traversing string 'cs'
>
> I'm not sure what you mean about an extra loop.

I just mean above "traversing string 'cs'" in strpbrk(s, "") is 
unnecessary. Sorry for making the ambiguity :-(

> Thanks,
>
> -- Steve