Re: [RFC] perf trace: Fix compilation error for make NO_LIBBPF=1 DEBUG=1

[Jiri Olsa <jolsa@redhat.com>]

On Mon, May 18, 2020 at 01:09:53PM -0300, Arnaldo Carvalho de Melo wrote:
> Em Mon, May 18, 2020 at 04:35:28PM +0200, Jiri Olsa escreveu:
> > On Mon, May 18, 2020 at 11:19:15AM -0300, Arnaldo Carvalho de Melo wrote:
> > > Em Mon, May 18, 2020 at 04:10:27PM +0200, Jiri Olsa escreveu:
> > > > I haven't tested if this breaks some perf trace functionality,
> > > > hence RFC ;-)
> > > 
> > > Thanks for the patch, looks ok, applying, please let me know if you need
> > > to do something else with it.
> > 
> > just wasn't sure the hook will work with NULL,
> > so if you're ok with it, then it's ok ;-)
> > 
> > thanks,
> > jirka
> 
> you forgot this, right?

ugh yea.. I did not test the test :-\ sry

jirka

> 
> 
> diff --git a/tools/perf/tests/make b/tools/perf/tests/make
> index c3c59def9f87..29ce0da7fca6 100644
> --- a/tools/perf/tests/make
> +++ b/tools/perf/tests/make
> @@ -145,6 +145,7 @@ run += make_no_libaudit
>  run += make_no_libbionic
>  run += make_no_auxtrace
>  run += make_no_libbpf
> +run += make_no_libbpf_DEBUG
>  run += make_with_babeltrace
>  run += make_with_clangllvm
>  run += make_help
>  
> > > 
> > > - Arnaldo
> > >  
> > > > The perf compilation fails for NO_LIBBPF=1 DEBUG=1 with:
> > > > 
> > > >   $ make NO_LIBBPF=1 DEBUG=1
> > > >     BUILD:   Doing 'make -j8' parallel build
> > > >     CC       builtin-trace.o
> > > >     LD       perf-in.o
> > > >     LINK     perf
> > > >   /usr/bin/ld: perf-in.o: in function `trace__find_bpf_map_by_name':
> > > >   /home/jolsa/kernel/linux-perf/tools/perf/builtin-trace.c:4608: undefined reference to `bpf_object__find_map_by_name'
> > > >   collect2: error: ld returned 1 exit status
> > > >   make[2]: *** [Makefile.perf:631: perf] Error 1
> > > >   make[1]: *** [Makefile.perf:225: sub-make] Error 2
> > > >   make: *** [Makefile:70: all] Error 2
> > > > 
> > > > Moving trace__find_bpf_map_by_name calls under HAVE_LIBBPF_SUPPORT
> > > > ifdef and add make test for this.
> > > > 
> > > > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> > > > ---
> > > >  tools/perf/builtin-trace.c | 54 ++++++++++++++++++++++++--------------
> > > >  tools/perf/tests/make      |  1 +
> > > >  2 files changed, 35 insertions(+), 20 deletions(-)
> > > > 
> > > > diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
> > > > index 56bcf1ab19f8..61bafca1018a 100644
> > > > --- a/tools/perf/builtin-trace.c
> > > > +++ b/tools/perf/builtin-trace.c
> > > > @@ -3174,6 +3174,26 @@ static int trace__set_ev_qualifier_tp_filter(struct trace *trace)
> > > >  }
> > > >  
> > > >  #ifdef HAVE_LIBBPF_SUPPORT
> > > > +static struct bpf_map *trace__find_bpf_map_by_name(struct trace *trace, const char *name)
> > > > +{
> > > > +	if (trace->bpf_obj == NULL)
> > > > +		return NULL;
> > > > +
> > > > +	return bpf_object__find_map_by_name(trace->bpf_obj, name);
> > > > +}
> > > > +
> > > > +static void trace__set_bpf_map_filtered_pids(struct trace *trace)
> > > > +{
> > > > +	trace->filter_pids.map = trace__find_bpf_map_by_name(trace, "pids_filtered");
> > > > +}
> > > > +
> > > > +static void trace__set_bpf_map_syscalls(struct trace *trace)
> > > > +{
> > > > +	trace->syscalls.map = trace__find_bpf_map_by_name(trace, "syscalls");
> > > > +	trace->syscalls.prog_array.sys_enter = trace__find_bpf_map_by_name(trace, "syscalls_sys_enter");
> > > > +	trace->syscalls.prog_array.sys_exit  = trace__find_bpf_map_by_name(trace, "syscalls_sys_exit");
> > > > +}
> > > > +
> > > >  static struct bpf_program *trace__find_bpf_program_by_title(struct trace *trace, const char *name)
> > > >  {
> > > >  	if (trace->bpf_obj == NULL)
> > > > @@ -3512,6 +3532,20 @@ static void trace__delete_augmented_syscalls(struct trace *trace)
> > > >  	trace->bpf_obj = NULL;
> > > >  }
> > > >  #else // HAVE_LIBBPF_SUPPORT
> > > > +static struct bpf_map *trace__find_bpf_map_by_name(struct trace *trace __maybe_unused,
> > > > +						   const char *name __maybe_unused)
> > > > +{
> > > > +	return NULL;
> > > > +}
> > > > +
> > > > +static void trace__set_bpf_map_filtered_pids(struct trace *trace __maybe_unused)
> > > > +{
> > > > +}
> > > > +
> > > > +static void trace__set_bpf_map_syscalls(struct trace *trace __maybe_unused)
> > > > +{
> > > > +}
> > > > +
> > > >  static int trace__set_ev_qualifier_bpf_filter(struct trace *trace __maybe_unused)
> > > >  {
> > > >  	return 0;
> > > > @@ -4600,26 +4634,6 @@ static int trace__parse_cgroups(const struct option *opt, const char *str, int u
> > > >  	return 0;
> > > >  }
> > > >  
> > > > -static struct bpf_map *trace__find_bpf_map_by_name(struct trace *trace, const char *name)
> > > > -{
> > > > -	if (trace->bpf_obj == NULL)
> > > > -		return NULL;
> > > > -
> > > > -	return bpf_object__find_map_by_name(trace->bpf_obj, name);
> > > > -}
> > > > -
> > > > -static void trace__set_bpf_map_filtered_pids(struct trace *trace)
> > > > -{
> > > > -	trace->filter_pids.map = trace__find_bpf_map_by_name(trace, "pids_filtered");
> > > > -}
> > > > -
> > > > -static void trace__set_bpf_map_syscalls(struct trace *trace)
> > > > -{
> > > > -	trace->syscalls.map = trace__find_bpf_map_by_name(trace, "syscalls");
> > > > -	trace->syscalls.prog_array.sys_enter = trace__find_bpf_map_by_name(trace, "syscalls_sys_enter");
> > > > -	trace->syscalls.prog_array.sys_exit  = trace__find_bpf_map_by_name(trace, "syscalls_sys_exit");
> > > > -}
> > > > -
> > > >  static int trace__config(const char *var, const char *value, void *arg)
> > > >  {
> > > >  	struct trace *trace = arg;
> > > > diff --git a/tools/perf/tests/make b/tools/perf/tests/make
> > > > index 5d0c3a9c47a1..c3c59def9f87 100644
> > > > --- a/tools/perf/tests/make
> > > > +++ b/tools/perf/tests/make
> > > > @@ -84,6 +84,7 @@ make_no_libaudit    := NO_LIBAUDIT=1
> > > >  make_no_libbionic   := NO_LIBBIONIC=1
> > > >  make_no_auxtrace    := NO_AUXTRACE=1
> > > >  make_no_libbpf	    := NO_LIBBPF=1
> > > > +make_no_libbpf_DEBUG := NO_LIBBPF=1 DEBUG=1
> > > >  make_no_libcrypto   := NO_LIBCRYPTO=1
> > > >  make_with_babeltrace:= LIBBABELTRACE=1
> > > >  make_no_sdt	    := NO_SDT=1
> > > > -- 
> > > > 2.25.4
> > > > 
> > > 
> > > -- 
> > > 
> > > - Arnaldo
> > > 
> > 
> 
> -- 
> 
> - Arnaldo
>