Messages in this thread | | | Date | Mon, 24 Aug 2009 00:54:08 -0700 | From | "Justin P. Mattock" <> | Subject | Re: system gets stuck in a lock during boot |
| |
Peter Zijlstra wrote: > On Mon, 2009-08-24 at 14:13 +0800, Li Zefan wrote: > >> Peter Zijlstra wrote: >> >>> On Mon, 2009-08-24 at 10:41 +0800, Li Zefan wrote: >>> >>> >>>>> @@ -940,7 +940,7 @@ event_create_dir(struct ftrace_event_call *call, struct dentr >>>>> entry = trace_create_file("enable", 0644, call->dir, call, >>>>> enable); >>>>> >>>>> - if (call->id) >>>>> + if (call->id&& call->profile_enable) >>>>> >>>> We do an extra check on ->profile_enable, shouldn't cause bug.. >>>> >>>> >>>>> entry = trace_create_file("id", 0444, call->dir, call, >>>>> id); >>>>> >>>> Any way, I don't think this commit does the right thing: >>>> >>>> - If CONFIG_EVENT_PROFILE=y, we'll create events/<dir>/<event>/id, >>>> except events/ftrace/<event>/id. >>>> >>>> - if CONFIG_EVENT_PROFILE=n, there's no 'id' file at all! >>>> >>>> I think it's better to skip ftrace/ dir in perf tool code, instead of >>>> skipping creating id files in ftrace code. >>>> >>> No, it does do the right thing. Your patch breaks things because not all >>> tracepoints are created through TRACE_EVENT() and will thus not have >>> their profile_enable/disable hooks set. >>> >>> By giving them an ID file, there is no way to distinguish good from bad >>> tracepoints. >>> >>> >> But removing the id file from events/ftrace/ might break some ftrace >> binary parsers? >> >> And this commit makes 'id' file disapeared with CONFIG_EVENT_PROFILE=n. >> > > I introduced the id file for EVENT_PROFILE, tough luck if someone else > relies on it. > > >>> Expempting ftrace is no solid solution, suppose someone else does a >>> TRACE_EVENT_FORMAT() tracepoint, how would you know you could use it as >>> a profile event source? >>> >>> >> Agree. >> >> >>> The id files really must stay conditional. >>> >>> >> I don't think it's a good idea to connect it with perfcounter >> this way. Wouldn't adding a 'profilable' file more intuitive? >> > > its called: id ;-) > > Alright, I'm going to go back to the beginning and start my build from scratch(make sure things are legit).
Justin P. Mattock
| |