Re: [PATCH 6/7] perf auxtrace: Make auxtrace_queues__add_buffer() allocate struct buffer

From: Arnaldo Carvalho de Melo
Date: Thu Apr 05 2018 - 07:33:13 EST


Em Thu, Apr 05, 2018 at 09:17:01AM +0300, Adrian Hunter escreveu:
> On 07/03/18 16:11, Arnaldo Carvalho de Melo wrote:
> > Em Wed, Mar 07, 2018 at 10:06:50AM +0200, Adrian Hunter escreveu:
> >> On 06/03/18 22:25, Arnaldo Carvalho de Melo wrote:
> >>> Em Tue, Mar 06, 2018 at 11:13:17AM +0200, Adrian Hunter escreveu:
> >>>> In preparation for supporting AUX area sampling buffers,
> >>>> auxtrace_queues__add_buffer() needs to be more generic. To that end, move
> >>>> memory allocation for struct buffer into it.
> >>>>
> >>>> Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> >>>> ---
> >>>> tools/perf/util/auxtrace.c | 54 +++++++++++++++++++++-------------------------
> >>>> 1 file changed, 24 insertions(+), 30 deletions(-)
> >>>>
> >>>> diff --git a/tools/perf/util/auxtrace.c b/tools/perf/util/auxtrace.c
> >>>> index fb357a00dd86..e1aff91c54a8 100644
> >>>> --- a/tools/perf/util/auxtrace.c
> >>>> +++ b/tools/perf/util/auxtrace.c
> >>>> @@ -308,7 +308,11 @@ static int auxtrace_queues__add_buffer(struct auxtrace_queues *queues,
> >>>> struct auxtrace_buffer *buffer,
> >>>> struct auxtrace_buffer **buffer_ptr)
> >>>> {
> >>>> - int err;
> >>>> + int err = -ENOMEM;
> >>>> +
> >>>> + buffer = memdup(buffer, sizeof(*buffer));
> >>>
> >>> this is a bit strange, why not make buffer a local variable in this
> >>> function then?
> >>
> >> Do you mean the following?
> >>
> >> struct auxtrace_buffer *new_buf;
> >>
> >> new_buf = memdup(buffer, sizeof(*buffer));
> >
> > I hadn't noticed that you were using buffer as both r and l value :-\
> >
> > If all you want is to receive that buffer, duplicate it and then use
> > just the duplicate, not needing any reference to the original buffer,
> > then your code is correct, it just looked strange from a quick look, so
> > nevermind, I'll continue processing this one and the others.
>
> Looks like this patch and patch 7 "perf auxtrace: Make
> auxtrace_queues__add_buffer() do CPU filtering" got left behind. They still
> apply cleanly.

Thanks for the reminder, I'll process it.

- Arnaldo