From: Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>
To: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>, Jiri Olsa <jolsa@redhat.com>,
Namhyung Kim <namhyung@kernel.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] perf/probe: Skip same probe address
Date: Fri, 20 Sep 2019 15:26:46 -0300 [thread overview]
Message-ID: <20190920182646.GC4865@kernel.org> (raw)
In-Reply-To: <156886447061.10772.4261569305869149178.stgit@devnote2>
Em Thu, Sep 19, 2019 at 12:41:10PM +0900, Masami Hiramatsu escreveu:
> Fix to skip making a same probe address on given line.
>
> Since dwarf line info contains several entries for one line
> with different column, perf probe will make a different
> probe on same address if user specifies a probe point by
> "function:line" or "file:line".
>
> e.g.
> $ perf probe -D kernel_read:8
> p:probe/kernel_read_L8 kernel_read+39
> p:probe/kernel_read_L8_1 kernel_read+39
>
> This skips such duplicated probe address.
Thanks, applied to perf/urgent.
- Arnaldo
> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
> ---
> tools/perf/util/probe-finder.c | 19 +++++++++++++++++++
> 1 file changed, 19 insertions(+)
>
> diff --git a/tools/perf/util/probe-finder.c b/tools/perf/util/probe-finder.c
> index 025fc4491993..02ca95deaf2c 100644
> --- a/tools/perf/util/probe-finder.c
> +++ b/tools/perf/util/probe-finder.c
> @@ -1244,6 +1244,17 @@ static int expand_probe_args(Dwarf_Die *sc_die, struct probe_finder *pf,
> return n;
> }
>
> +static bool trace_event_finder_overlap(struct trace_event_finder *tf)
> +{
> + int i;
> +
> + for (i = 0; i < tf->ntevs; i++) {
> + if (tf->pf.addr == tf->tevs[i].point.address)
> + return true;
> + }
> + return false;
> +}
> +
> /* Add a found probe point into trace event list */
> static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf)
> {
> @@ -1254,6 +1265,14 @@ static int add_probe_trace_event(Dwarf_Die *sc_die, struct probe_finder *pf)
> struct perf_probe_arg *args = NULL;
> int ret, i;
>
> + /*
> + * For some reason (e.g. different column assigned to same address)
> + * This callback can be called with the address which already passed.
> + * Ignore it first.
> + */
> + if (trace_event_finder_overlap(tf))
> + return 0;
> +
> /* Check number of tevs */
> if (tf->ntevs == tf->max_tevs) {
> pr_warning("Too many( > %d) probe point found.\n",
--
- Arnaldo
next prev parent reply other threads:[~2019-09-20 18:27 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-19 3:41 [PATCH] perf/probe: Skip same probe address Masami Hiramatsu
2019-09-20 18:26 ` Arnaldo Carvalho de Melo [this message]
2019-09-22 10:52 ` [tip: perf/urgent] perf probe: Skip same probe address for a given line tip-bot2 for Masami Hiramatsu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20190920182646.GC4865@kernel.org \
--to=arnaldo.melo@gmail.com \
--cc=jolsa@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mhiramat@kernel.org \
--cc=namhyung@kernel.org \
--cc=wangnan0@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).