Re: [RFC] perf script: callchain handling is not useful

From: Namhyung Kim
Date: Wed Aug 29 2018 - 20:33:32 EST


Hi,

On Wed, Aug 29, 2018 at 08:14:12AM -0700, Stephane Eranian wrote:
> On Wed, Aug 29, 2018 at 6:54 AM Arnaldo Carvalho de Melo
> <acme@xxxxxxxxxx> wrote:
> >
> > Em Tue, Aug 28, 2018 at 07:41:31PM -0700, Stephane Eranian escreveu:
> > > Hi,
> > >
> > > I am doing the following simple collection with callchain and load profiling:
> > >
> > > $ perf record -g -d -e cpu/event=0xd0,umask=0x81/pp my_test_program
> > >
> > > But when I type:
> > > $ perf script -F ip,addr
> > > ffff9d4821346878
> > > ffffffff9d58df25
> > > ffffffff9d58e054
> > > ffffffff9d5965bb
> > > ffffffff9d640650
> > > ffffffff9d697d06
> > > ffffffff9d63ec60
> > > ffffffff9d640322
> > > ffffffff9d64070c
> > > ffffffff9d455a60
> > > 7030c7
> > >
> > > ffff9d4638ba84a0
> > > ffffffff9d5df447
> > > ffffffff9d5eaf4a
> > > ffffffff9d63e165
> > > ffffffff9d63e439
> > > ffffffff9d697d98
> > > ffffffff9d63ec60
> > > ffffffff9d640322
> > > ffffffff9d64070c
> > > ffffffff9d455a60
> > > 7030c7
> > > I also see the callchain and it is not clear which is the IP. Further
> > > more parsing becomes more difficult because of multiple lines per
> > > sample. I understand that multiline is likely because of
> > > symbolization. But if I don't want symbolization, it should be
> > > possible to print all in one line.
> >
> > Humm, to have this not break possibly existing scripts, perhaps we can
> > have something like:
> >
> > $ perf script -F ip,-callchain,addr
> >
> > ?
> >
> > And if asked explicitely for the callchain, then it gets added in the
> > same line?
> >
> Yeah, that should do it.
> Thanks.

I found this:

$ perf script -h |& grep -A1 hide
-G, --hide-call-graph
When printing symbols do not display call chain

Thanks,
Namhyung