Re: [PATCH 12/12] perf maps: Set maps pointer in the kmap area for kernel maps

[Arnaldo Carvalho de Melo]

Em Wed, Dec 18, 2019 at 10:05:04AM +0100, Jiri Olsa escreveu:
> On Tue, Dec 17, 2019 at 11:48:28AM -0300, Arnaldo Carvalho de Melo wrote:
> 
> SNIP
> 
> > +	machine->vmlinux_map = map__new2(0, kernel, &machine->kmaps);
> >  	if (machine->vmlinux_map == NULL)
> >  		return -1;
> >  
> > @@ -1098,7 +1097,6 @@ __machine__create_kernel_maps(struct machine *machine, struct dso *kernel)
> >  	if (!kmap)
> >  		return -1;
> >  
> > -	kmap->kmaps = &machine->kmaps;
> >  	maps__insert(&machine->kmaps, map);
> >  
> >  	return 0;
> > diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
> > index fdd5bddb3075..a2cdfe62df94 100644
> > --- a/tools/perf/util/map.c
> > +++ b/tools/perf/util/map.c
> > @@ -223,7 +223,7 @@ struct map *map__new(struct machine *machine, u64 start, u64 len,
> >   * they are loaded) and for vmlinux, where only after we load all the
> >   * symbols we'll know where it starts and ends.
> >   */
> > -struct map *map__new2(u64 start, struct dso *dso)
> > +struct map *map__new2(u64 start, struct dso *dso, struct maps *kmaps)
> >  {
> >  	struct map *map = calloc(1, (sizeof(*map) +
> >  				     (dso->kernel ? sizeof(struct kmap) : 0)));
> > @@ -232,6 +232,19 @@ struct map *map__new2(u64 start, struct dso *dso)
> >  		 * ->end will be filled after we load all the symbols
> >  		 */
> >  		map__init(map, start, 0, 0, dso);
> 
> we are passing NULL for kmaps in some cases,
> should we check it in here and warn?
> 
> 		if (!WARN_ON_ONCE(!kmaps, "too bad..") && dso->kernel)

I'll add that, yeah

- Arnaldo