perf probe: Fix an error when deleting probes successfully
perf probe: Fix an error when deleting probes successfully

Fix a bug in del_perf_probe_events() which returns an error (-ENOENT)
even if the probes are successfully deleted.

This happens only if the probes are on user-apps and not on kernel,
simply because it doesn't clear the previous error.

So, without this fix, we get an error even though events are being
successfully removed.

  ------
  # ./perf probe -x ./perf del_perf_probe_events
  Added new event:
    probe_perf:del_perf_probe_events (on del_perf_probe_events in ...

  You can now use it in all perf tools, such as:

          perf record -e probe_perf:del_perf_probe_events -aR sleep 1

  # ./perf probe -d \*:\*
  Removed event: probe_perf:del_perf_probe_events
    Error: Failed to delete events.
  ------

This fixes the above error.
  ------
  # ./perf probe -d \*:\*
  Removed event: probe_perf:del_perf_probe_events
  ------

Reported-by: Arnaldo Carvalho de Melo <293abb6b76d7791c0732cc517d38c4b5c734b87f@kernel.org>
Signed-off-by: Masami Hiramatsu <60fcdccfd958d359debfe6e6e7417cd7f1aaa9e3@hitachi.com>
Tested-by: Arnaldo Carvalho de Melo <293abb6b76d7791c0732cc517d38c4b5c734b87f@redhat.com>
Cc: David Ahern <b80c1600f604d3b0d768f26f90a76757e76005dd@gmail.com>
Cc: Jiri Olsa <2c6594f608aa3d41e98d48846a6328831f7084ad@redhat.com>
Cc: Namhyung Kim <5c915a589b3ddf58cebf14bec41bcc143b37ac3c@kernel.org>
Cc: Peter Zijlstra <3fddac958924aef220f202ca567388ddab3f14a8@infradead.org>
Cc: Richard Weinberger <320bca71fc381a4a025636043ca86e734e31cf8b@nod.at>
Link: bb531b3b51e1582ed857e2d17724823cabeae766@localhost.localdomain
Signed-off-by: Arnaldo Carvalho de Melo <293abb6b76d7791c0732cc517d38c4b5c734b87f@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs