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

From: Jiri Olsa
Date: Wed Dec 18 2019 - 04:05:17 EST


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)


jirka