On Wed, May 22, 2019 at 01:06:57PM -0300, Arnaldo Carvalho de Melo wrote: > Em Wed, May 08, 2019 at 03:20:06PM +0200, Jiri Olsa escreveu: > > We need to preserve eBPF maps even if they are > > covered by kcore, because we need to access > > eBPF dso for source data. > > So, I reordered this one with the previous, as to get the output you > added to 07/12 we need what is in 08/12, and they are otherwise > completely independent, right?
right jirka > > - Arnaldo > > > Adding map_groups__merge_in function to do that. > > It merges map into map_groups by splitting the > > new map within the existing map regions. > > > > Suggested-by: Adrian Hunter <[email protected]> > > Link: http://lkml.kernel.org/n/[email protected] > > Signed-off-by: Jiri Olsa <[email protected]> > > --- > > tools/perf/util/symbol.c | 97 ++++++++++++++++++++++++++++++++++++++-- > > 1 file changed, 93 insertions(+), 4 deletions(-) > > > > diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c > > index 5cbad55cd99d..29780fcd049c 100644 > > --- a/tools/perf/util/symbol.c > > +++ b/tools/perf/util/symbol.c > > @@ -1166,6 +1166,85 @@ static int kcore_mapfn(u64 start, u64 len, u64 > > pgoff, void *data) > > return 0; > > } > > > > +/* > > + * Merges map into map_groups by splitting the new map > > + * within the existing map regions. > > + */ > > +static int map_groups__merge_in(struct map_groups *kmaps, struct map > > *new_map) > > +{ > > + struct map *old_map; > > + LIST_HEAD(merged); > > + > > + for (old_map = map_groups__first(kmaps); old_map; > > + old_map = map_groups__next(old_map)) { > > + > > + /* no overload with this one */ > > + if (new_map->end < old_map->start || > > + new_map->start >= old_map->end) > > + continue; > > + > > + if (new_map->start < old_map->start) { > > + /* > > + * |new...... > > + * |old.... > > + */ > > + if (new_map->end < old_map->end) { > > + /* > > + * |new......| -> |new..| > > + * |old....| -> |old....| > > + */ > > + new_map->end = old_map->start; > > + } else { > > + /* > > + * |new.............| -> |new..| |new..| > > + * |old....| -> |old....| > > + */ > > + struct map *m = map__clone(new_map); > > + > > + if (!m) > > + return -ENOMEM; > > + > > + m->end = old_map->start; > > + list_add_tail(&m->node, &merged); > > + new_map->start = old_map->end; > > + } > > + } else { > > + /* > > + * |new...... > > + * |old.... > > + */ > > + if (new_map->end < old_map->end) { > > + /* > > + * |new..| -> x > > + * |old.........| -> |old.........| > > + */ > > + map__put(new_map); > > + new_map = NULL; > > + break; > > + } else { > > + /* > > + * |new......| -> |new...| > > + * |old....| -> |old....| > > + */ > > + new_map->start = old_map->end; > > + } > > + } > > + } > > + > > + while (!list_empty(&merged)) { > > + old_map = list_entry(merged.next, struct map, node); > > + list_del_init(&old_map->node); > > + map_groups__insert(kmaps, old_map); > > + map__put(old_map); > > + } > > + > > + if (new_map) { > > + map_groups__insert(kmaps, new_map); > > + map__put(new_map); > > + } > > + return 0; > > +} > > + > > static int dso__load_kcore(struct dso *dso, struct map *map, > > const char *kallsyms_filename) > > { > > @@ -1222,7 +1301,12 @@ static int dso__load_kcore(struct dso *dso, struct > > map *map, > > while (old_map) { > > struct map *next = map_groups__next(old_map); > > > > - if (old_map != map) > > + /* > > + * We need to preserve eBPF maps even if they are > > + * covered by kcore, because we need to access > > + * eBPF dso for source data. > > + */ > > + if (old_map != map && !__map__is_bpf_prog(old_map)) > > map_groups__remove(kmaps, old_map); > > old_map = next; > > } > > @@ -1256,11 +1340,16 @@ static int dso__load_kcore(struct dso *dso, struct > > map *map, > > map_groups__remove(kmaps, map); > > map_groups__insert(kmaps, map); > > map__put(map); > > + map__put(new_map); > > } else { > > - map_groups__insert(kmaps, new_map); > > + /* > > + * Merge kcore map into existing maps, > > + * and ensure that current maps (eBPF) > > + * stay intact. > > + */ > > + if (map_groups__merge_in(kmaps, new_map)) > > + goto out_err; > > } > > - > > - map__put(new_map); > > } > > > > if (machine__is(machine, "x86_64")) { > > -- > > 2.20.1 > > -- > > - Arnaldo
