Messages in this thread | | | Date | Thu, 10 Sep 2015 11:23:25 +0900 | From | Namhyung Kim <> | Subject | Re: [PATCH v2 1/5] perf probe: Split add_perf_probe_events() |
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On Sun, Sep 06, 2015 at 03:47:37PM +0800, Wangnan (F) wrote: > Hi Namhyung,
Hi,
> > Thanks for this patchset. > > Could you plase have a look at patch 5/27 and 6/27 in my newest pull > request? > These 2 patches utilize new probing API to create probe point and collect > probe_trace_events. I'm not very sure I fully understand your design > principle, > especially the cleanup part, because I can see different functions dealing > with > cleanup: > > cleanup_perf_probe_events > del_perf_probe_events > clear_perf_probe_event > clear_probe_trace_event > > But non of them works perfectly for me.
The cleanup_perf_probe_events() is just to keep the existing logic as long as possible. But I think it needs to call clear_perf_probe_event().
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.
So for your case, IMHO it'd better keeping the perf/trace events after probing and reusing the events for unprobing. I'll take a look at it.
> > In bpf_prog_priv__clear() function of 6/27, I copied some code from > cleanup_perf_probe_events(), because I think when destroying bpf programs, > the probe_trace_events should also be cleanuped, but we don't need call > exit_symbol_maps() many times, because we are in 'perf record', and not > sure whether other parts of perf need symbol maps. Otherwise I think > directly > calling cleanup_perf_probe_events() sould be better.
Yeah, I also think exit_symbol_maps() should not be a part of the cleanup. I'll send a patch soon.
> > You can find patch from: > > http://lkml.kernel.org/n/1441523623-152703-6-git-send-email-wangnan0@huawei.com > > http://lkml.kernel.org/n/1441523623-152703-7-git-send-email-wangnan0@huawei.com
Thanks for your work! Namhyung
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