[PATCH v6 16/47] perf maps: Refactor maps__fixup_overlappings

From: Ian Rogers
Date: Wed Dec 06 2023 - 20:22:25 EST


Rename to maps__fixup_overlap_and_insert as the given mapping is
always inserted. Factor out first_ending_after as a utility
function. Minor variable name changes. Switch to using debug_file()
rather than passing a debug FILE*.

Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
---
tools/perf/util/maps.c | 57 ++++++++++++++++++++++++----------------
tools/perf/util/maps.h | 2 +-
tools/perf/util/thread.c | 3 +--
3 files changed, 37 insertions(+), 25 deletions(-)

diff --git a/tools/perf/util/maps.c b/tools/perf/util/maps.c
index f13fd3a9686b..94a97923527d 100644
--- a/tools/perf/util/maps.c
+++ b/tools/perf/util/maps.c
@@ -334,20 +334,16 @@ size_t maps__fprintf(struct maps *maps, FILE *fp)
return args.printed;
}

-int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
+/*
+ * Find first map where end > map->start.
+ * Same as find_vma() in kernel.
+ */
+static struct rb_node *first_ending_after(struct maps *maps, const struct map *map)
{
struct rb_root *root;
struct rb_node *next, *first;
- int err = 0;
-
- down_write(maps__lock(maps));

root = maps__entries(maps);
-
- /*
- * Find first map where end > map->start.
- * Same as find_vma() in kernel.
- */
next = root->rb_node;
first = NULL;
while (next) {
@@ -361,8 +357,23 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
} else
next = next->rb_right;
}
+ return first;
+}
+
+/*
+ * Adds new to maps, if new overlaps existing entries then the existing maps are
+ * adjusted or removed so that new fits without overlapping any entries.
+ */
+int maps__fixup_overlap_and_insert(struct maps *maps, struct map *new)
+{
+
+ struct rb_node *next;
+ int err = 0;
+ FILE *fp = debug_file();
+
+ down_write(maps__lock(maps));

- next = first;
+ next = first_ending_after(maps, new);
while (next && !err) {
struct map_rb_node *pos = rb_entry(next, struct map_rb_node, rb_node);
next = rb_next(&pos->rb_node);
@@ -371,27 +382,27 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
* Stop if current map starts after map->end.
* Maps are ordered by start: next will not overlap for sure.
*/
- if (map__start(pos->map) >= map__end(map))
+ if (map__start(pos->map) >= map__end(new))
break;

if (verbose >= 2) {

if (use_browser) {
pr_debug("overlapping maps in %s (disable tui for more info)\n",
- map__dso(map)->name);
+ map__dso(new)->name);
} else {
- fputs("overlapping maps:\n", fp);
- map__fprintf(map, fp);
+ pr_debug("overlapping maps:\n");
+ map__fprintf(new, fp);
map__fprintf(pos->map, fp);
}
}

- rb_erase_init(&pos->rb_node, root);
+ rb_erase_init(&pos->rb_node, maps__entries(maps));
/*
* Now check if we need to create new maps for areas not
* overlapped by the new map:
*/
- if (map__start(map) > map__start(pos->map)) {
+ if (map__start(new) > map__start(pos->map)) {
struct map *before = map__clone(pos->map);

if (before == NULL) {
@@ -399,7 +410,7 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
goto put_map;
}

- map__set_end(before, map__start(map));
+ map__set_end(before, map__start(new));
err = __maps__insert(maps, before);
if (err) {
map__put(before);
@@ -411,7 +422,7 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
map__put(before);
}

- if (map__end(map) < map__end(pos->map)) {
+ if (map__end(new) < map__end(pos->map)) {
struct map *after = map__clone(pos->map);

if (after == NULL) {
@@ -419,10 +430,10 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
goto put_map;
}

- map__set_start(after, map__end(map));
- map__add_pgoff(after, map__end(map) - map__start(pos->map));
- assert(map__map_ip(pos->map, map__end(map)) ==
- map__map_ip(after, map__end(map)));
+ map__set_start(after, map__end(new));
+ map__add_pgoff(after, map__end(new) - map__start(pos->map));
+ assert(map__map_ip(pos->map, map__end(new)) ==
+ map__map_ip(after, map__end(new)));
err = __maps__insert(maps, after);
if (err) {
map__put(after);
@@ -436,6 +447,8 @@ int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp)
map__put(pos->map);
free(pos);
}
+ /* Add the map. */
+ err = __maps__insert(maps, new);
up_write(maps__lock(maps));
return err;
}
diff --git a/tools/perf/util/maps.h b/tools/perf/util/maps.h
index b94ad5c8fea7..62e94d443c02 100644
--- a/tools/perf/util/maps.h
+++ b/tools/perf/util/maps.h
@@ -133,7 +133,7 @@ struct addr_map_symbol;

int maps__find_ams(struct maps *maps, struct addr_map_symbol *ams);

-int maps__fixup_overlappings(struct maps *maps, struct map *map, FILE *fp);
+int maps__fixup_overlap_and_insert(struct maps *maps, struct map *new);

struct map *maps__find_by_name(struct maps *maps, const char *name);

diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c
index b6986a81aa6d..3d47b5c5528b 100644
--- a/tools/perf/util/thread.c
+++ b/tools/perf/util/thread.c
@@ -345,8 +345,7 @@ int thread__insert_map(struct thread *thread, struct map *map)
if (ret)
return ret;

- maps__fixup_overlappings(thread__maps(thread), map, stderr);
- return maps__insert(thread__maps(thread), map);
+ return maps__fixup_overlap_and_insert(thread__maps(thread), map);
}

struct thread__prepare_access_maps_cb_args {
--
2.43.0.rc2.451.g8631bc7472-goog