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

Arnaldo Carvalho de Melo
2019-12-18T14:24:38Z

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