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

From: Masami Hiramatsu
Date: Fri Mar 13 2015 - 07:20:28 EST


(2015/03/13 5:24), Arnaldo Carvalho de Melo wrote:
> 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?

As far as I can see, this is not enough for fixing that issue.
Could you fold the first half of [4/8] to this patch?
I also have some comments on it. See below.

>
>> 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;

Oh please, don't reuse 'char c' for a boolean flag, you should
introduce new 'bool file_loc' etc.

>> + if (!strpbrk(arg, "+@%") && (ptr = strpbrk(arg, ";:")) != NULL) {
>> + /* This is a file spec if it includes a '.' before ; or : */
>> + if (memchr(arg, '.', ptr-arg))
^^ add spaces around '-'.

Thank you,


>> + 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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--
Masami HIRAMATSU
Software Platform Research Dept. Linux Technology Research Center
Hitachi, Ltd., Yokohama Research Laboratory
E-mail: masami.hiramatsu.pt@xxxxxxxxxxx


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