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Re: [RFC PATCH v9 49/50 -fix] perf probe: Init symbol as kprobe if any event is kprobe

From Arnaldo Carvalho de Melo <acme@kernel.org>
Newsgroups linux.kernel
Subject Re: [RFC PATCH v9 49/50 -fix] perf probe: Init symbol as kprobe if any event is kprobe
Date 2015-06-29 16:40 +0200
Message-ID <pGIo1-5Kx-3@gated-at.bofh.it> (permalink)
References <pFCE2-1an-25@gated-at.bofh.it> <pFXp7-5B5-7@gated-at.bofh.it>
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Em Sat, Jun 27, 2015 at 12:25:45PM +0000, Wang Nan escreveu:
> Before this patch, add_perf_probe_events() init symbol maps only for
> uprobe if the first 'struct perf_probe_event' passed to it is a uprobe
> event. This is a trick because 'perf probe''s command line syntax
> constrains the first elements of the probe_event arrays must be kprobes
> if there is one.
> 
> However, with the incoming BPF uprobe support, the constrain is not
> hold since 'perf record' will also probe on k/u probes through BPF
> object, and is possible to pass an array with kprobe but the first
> element is uprobe.
> 
> This patch init symbol maps for kprobes even if all of events are
> uprobes, because the extra cost should be small enough.
> 
> Signed-off-by: Wang Nan <wangnan0@huawei.com>
> ---

Please add more info here, i.e. is this to be applied on top of the
original 49/50? I guess so, but please state this in the future to speed
things up.

- Arnaldo

>  tools/perf/util/probe-event.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> index ea08015..e74ca8f 100644
> --- a/tools/perf/util/probe-event.c
> +++ b/tools/perf/util/probe-event.c
> @@ -2804,7 +2804,7 @@ int add_perf_probe_events(struct perf_probe_event *pevs, int npevs,
>  {
>  	int i, ret;
>  
> -	ret = init_symbol_maps(pevs->uprobes);
> +	ret = init_symbol_maps(false);
>  	if (ret < 0)
>  		return ret;
>  
> -- 
> 1.8.3.4
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Re: [RFC PATCH v9 49/50 -fix] perf probe: Init symbol as kprobe if  any event is kprobe Arnaldo Carvalho de Melo <acme@kernel.org> - 2015-06-29 16:40 +0200
  Re: [RFC PATCH v9 49/50 -fix] perf probe: Init symbol as kprobe if  any event is kprobe "Wangnan (F)" <wangnan0@huawei.com> - 2015-06-30 03:50 +0200
    Re: [RFC PATCH v9 49/50 -fix] perf probe: Init symbol as kprobe if  any event is kprobe "Wangnan (F)" <wangnan0@huawei.com> - 2015-07-01 03:40 +0200

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