On Fri, 10 Jul 2020 16:48:47 +0530
Srikar Dronamraju <sri...@linux.vnet.ibm.com> wrote:
> * Masami Hiramatsu <mhira...@kernel.org> [2020-07-09 17:07:01]:
>
> > There is a case that the several same-name symbols points
> > same address. In that case, perf probe returns an error.
> >
> > E.g.
> >
> > With this patch;
> >
> > # perf probe -x /lib64/libc-2.30.so -a "memcpy arg1=%di"
> > Failed to find the location of the '%di' variable at this address.
> > Perhaps it has been optimized out.
> > Use -V with the --range option to show '%di' location range.
> > Added new events:
> > probe_libc:memcpy (on memcpy in /usr/lib64/libc-2.30.so with
> > arg1=%di)
> > probe_libc:memcpy (on memcpy in /usr/lib64/libc-2.30.so with
> > arg1=%di)
> >
> > You can now use it in all perf tools, such as:
> >
> > perf record -e probe_libc:memcpy -aR sleep 1
> >
> >
> > Reported-by: Andi Kleen <a...@firstfloor.org>
> > Signed-off-by: Masami Hiramatsu <mhira...@kernel.org>
>
> One small nit:
>
> > ---
> > tools/perf/util/probe-event.c | 9 +++++++++
> > 1 file changed, 9 insertions(+)
> >
> > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> > index df713a5d1e26..1e95a336862c 100644
> > --- a/tools/perf/util/probe-event.c
> > +++ b/tools/perf/util/probe-event.c
> > @@ -2968,6 +2968,15 @@ static int find_probe_trace_events_from_map(struct
> > perf_probe_event *pev,
> > for (j = 0; j < num_matched_functions; j++) {
> > sym = syms[j];
> >
> > + /* There can be duplicated symbols in the map */
> > + for (i = 0; i < j; i++)
> > + if (sym->start == syms[i]->start) {
> > + pr_debug("find duplicated symbol %s @ %lx\n",
> > sym->name, sym->start);
>
> Would "Found" sound better than "find"?
OK.
>
> > + break;
> > + }
> > + if (i != j)
> > + continue;
> > +
>
> Reviewed-by: Srikar Dronamraju <sri...@linux.vnet.ibm.com>
Thank you!
>
>
> > tev = (*tevs) + ret;
> > tp = &tev->point;
> > if (ret == num_matched_functions) {
> >
>
> --
> Thanks and Regards
> Srikar Dronamraju
--
Masami Hiramatsu <mhira...@kernel.org>
