Re: [RFC/PATCHSET 0/5] perf ftrace: Implement function latency histogram (v1)

From: Namhyung Kim <namhyung@kernel.org>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>, Ingo Molnar <mingo@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Andi Kleen <ak@linux.intel.com>, Ian Rogers <irogers@google.com>,
	Stephane Eranian <eranian@google.com>,
	Song Liu <songliubraving@fb.com>,
	Changbin Du <changbin.du@gmail.com>
Subject: Re: [RFC/PATCHSET 0/5] perf ftrace: Implement function latency histogram (v1)
Date: Wed, 15 Dec 2021 10:08:53 -0800	[thread overview]
Message-ID: <CAM9d7cgKUHiJJXG5+OnzGv=5abS==ugxcnfrwgGxf35vyRb+Bw@mail.gmail.com> (raw)
In-Reply-To: <YboNUk+ThCpEf8mQ@kernel.org>

Hi Arnaldo,

On Wed, Dec 15, 2021 at 8:08 AM Arnaldo Carvalho de Melo
<acme@kernel.org> wrote:
>
> Em Wed, Dec 15, 2021 at 12:30:10PM -0300, Arnaldo Carvalho de Melo escreveu:
> > Em Mon, Dec 13, 2021 at 11:40:16AM -0800, Namhyung Kim escreveu:
> > > On Mon, Dec 13, 2021 at 10:24 AM Arnaldo Carvalho de Melo
> > > <acme@kernel.org> wrote:
> > > >
> > > > Em Mon, Nov 29, 2021 at 03:18:25PM -0800, Namhyung Kim escreveu:
> > > > > Hello,
> > > > >
> > > > > I've implemented 'latency' subcommand in the perf ftrace command to
> > > > > show a histogram of function latency.
> > > >
> > > > This still applies cleanly, I'll test it later.
> > >
> > > Thank you Arnaldo!  While I have some small modifications
> > > but the functionality should be the same.  Please let me know
> > > if you have any suggestions.
> >
> > So, it is failing here with:
>
> So that 'fd' variable and the cpumap.h problems goes away when the last
> patch is applied, but for bisection its better to apply the patch below
> to 4/5.

Sure, I will move them.  Thanks for pointing that out.

>
> I tested it all, cool stuff, will you resubmit soon?

Yep!

>
> I pushed it to the tmp.perf/ftrace_bpf branch on my repo at:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git
>
> https://git.kernel.org/pub/scm/linux/kernel/git/acme/linux.git/log/?h=tmp.perf/ftrace_bpf
>
> With committer testing notes.

Thanks for the test!
Namhyung

>
> > Fixed with:
> >
> >
> > diff --git a/tools/perf/util/bpf_ftrace.c b/tools/perf/util/bpf_ftrace.c
> > index 1975a6fe73c9fa8b..f5b49fc056ab8b95 100644
> > --- a/tools/perf/util/bpf_ftrace.c
> > +++ b/tools/perf/util/bpf_ftrace.c
> > @@ -5,6 +5,7 @@
> >
> >  #include <linux/err.h>
> >
> > +#include "util/cpumap.h"
> >  #include "util/ftrace.h"
> >  #include "util/debug.h"
> >  #include "util/bpf_counter.h"
> > @@ -15,7 +16,7 @@ static struct func_latency_bpf *skel;
> >
> >  int perf_ftrace__latency_prepare_bpf(struct perf_ftrace *ftrace)
> >  {
> > -     int fd, err;
> > +     int err;
> >       struct filter_entry *func;
> >       struct bpf_link *begin_link, *end_link;
> >
>
> --
>
> - Arnaldo