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References: <20220612061508.1449636-1-asmadeus@codewreck.org>
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From:   Ian Rogers <irogers@google.com>
Date:   Mon, 4 Jul 2022 14:39:05 -0700
Message-ID: <CAP-5=fXgNTW1eXRZhz-s_AfP+v1Oyx1zdksm-Q0B4YVPAgjKxw@mail.gmail.com>
Subject: Re: [PATCH] perf parse: Allow names to start with digits
To:     Dominique Martinet <asmadeus@codewreck.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org
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On Sat, Jun 11, 2022 at 11:16 PM Dominique Martinet
<asmadeus@codewreck.org> wrote:
>
> Tracepoints can start with digits, although we don't have many of these:
>
> $ rg -g '*.h' '\bTRACE_EVENT\([0-9]'
> net/mac802154/trace.h
> 53:TRACE_EVENT(802154_drv_return_int,
> ...
>
> net/ieee802154/trace.h
> 66:TRACE_EVENT(802154_rdev_add_virtual_intf,
> ...
>
> include/trace/events/9p.h
> 124:TRACE_EVENT(9p_client_req,
> ...
>
> Just allow names to start with digits too so e.g. perf probe -e '9p:*'
> works
>
> Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
> ---
>  tools/perf/util/parse-events.l | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l
> index 5b6e4b5249cf..4133d6950d29 100644
> --- a/tools/perf/util/parse-events.l
> +++ b/tools/perf/util/parse-events.l
> @@ -211,7 +211,7 @@ bpf_source  [^,{}]+\.c[a-zA-Z0-9._]*
>  num_dec                [0-9]+
>  num_hex                0x[a-fA-F0-9]+
>  num_raw_hex    [a-fA-F0-9]+
> -name           [a-zA-Z_*?\[\]][a-zA-Z0-9_*?.\[\]!]*
> +name           [a-zA-Z0-9_*?\[\]][a-zA-Z0-9_*?.\[\]!]*

Perhaps this would be cleaner as:
name           [a-zA-Z0-9_*?\[\]!]+
except that would allow a name to start with an exclamation. Would
that be an issue?

Thanks,
Ian

>  name_tag       [\'][a-zA-Z_*?\[\]][a-zA-Z0-9_*?\-,\.\[\]:=]*[\']
>  name_minus     [a-zA-Z_*?][a-zA-Z0-9\-_*?.:]*
>  drv_cfg_term   [a-zA-Z0-9_\.]+(=[a-zA-Z0-9_*?\.:]+)?
> --
> 2.36.1
>