Re: Re: [PATCH v2 1/5] perf probe: Split add_perf_probe_events()

[Namhyung Kim]

Hi Masami,

On Thu, Sep 10, 2015 at 05:00:07AM +0000, åæéå / HIRAMATUïMASAMI wrote:
> >From: Namhyung Kim [mailto:namhyung@xxxxxxxxx] On Behalf Of Namhyung Kim
> >The del_perf_probe_events() uses strfilter, but I think it can be
> >problematic if other instances or users are using similar events at
> >the same time.
> 
> Yeah, since perf probe doesn't lock the ftrace, there should be a
> timing bug, but it can be fixed easily by ignoring -ENOENT. :) 

By ignoring -ENOENT?  Are you saying that there's a race between two
deleters?  Yes, of course, but I think that the bug will hit an adder
and a deleter especially if automatic probing is used (by eBPF and/or
SDT recording).

What about this?