Re: [PATCHv2 2/8] perf probe: Improve detection of file/function name in the probe pattern

From: Arnaldo Carvalho de Melo
Date: Thu Mar 12 2015 - 16:25:27 EST


Em Thu, Mar 12, 2015 at 05:24:14PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Mon, Dec 15, 2014 at 08:20:32PM +0530, Naveen N. Rao escreveu:
> > Currently, perf probe considers patterns including a '.' to be a file.
> > However, this causes problems on powerpc ABIv1 where all functions have
> > a leading '.':
> >
> > $ perf probe -F | grep schedule_timeout_interruptible
> > .schedule_timeout_interruptible
> > $ perf probe .schedule_timeout_interruptible
> > Semantic error :File always requires line number or lazy pattern.
> > Error: Command Parse Error.
> >
> > Fix this by checking the probe pattern in more detail.
>
> Masami, can I have your Acked-by or Reviewed-by?

It is limited to powerpc, but I would even so be happy if you could look
at it,

Thanks,

- Arnaldo

> > Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
> > ---
> > tools/perf/util/probe-event.c | 23 ++++++++++++++++++++---
> > 1 file changed, 20 insertions(+), 3 deletions(-)
> >
> > diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c
> > index 28eb141..9943ff3 100644
> > --- a/tools/perf/util/probe-event.c
> > +++ b/tools/perf/util/probe-event.c
> > @@ -999,6 +999,24 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
> > arg = tmp;
> > }
> >
> > + /*
> > + * Check arg is function or file name and copy it.
> > + *
> > + * We consider arg to be a file spec if and only if it satisfies
> > + * all of the below criteria::
> > + * - it does not include any of "+@%",
> > + * - it includes one of ":;", and
> > + * - it has a period '.' in the name.
> > + *
> > + * Otherwise, we consider arg to be a function specification.
> > + */
> > + c = 0;
> > + if (!strpbrk(arg, "+@%") && (ptr = strpbrk(arg, ";:")) != NULL) {
> > + /* This is a file spec if it includes a '.' before ; or : */
> > + if (memchr(arg, '.', ptr-arg))
> > + c = 1;
> > + }
> > +
> > ptr = strpbrk(arg, ";:+@%");
> > if (ptr) {
> > nc = *ptr;
> > @@ -1009,10 +1027,9 @@ static int parse_perf_probe_point(char *arg, struct perf_probe_event *pev)
> > if (tmp == NULL)
> > return -ENOMEM;
> >
> > - /* Check arg is function or file and copy it */
> > - if (strchr(tmp, '.')) /* File */
> > + if (c == 1)
> > pp->file = tmp;
> > - else /* Function */
> > + else
> > pp->function = tmp;
> >
> > /* Parse other options */
> > --
> > 2.1.3
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