[PATCH 06/25] perf maps: Do not use an rbtree to sort by map name
From: Arnaldo Carvalho de Melo
Date: Tue Nov 19 2019 - 06:33:27 EST
From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
This is only used for the kernel maps, shave 24 bytes out 'struct map'
and just traverse the existing per ip rbtree to look for maps by name,
use a front end cache to reuse the last search if its the same name.
After this 'struct map' is down to just two cachelines:
$ pahole -C map ~/bin/perf
struct map {
union {
struct rb_node rb_node __attribute__((__aligned__(8))); /* 0 24 */
struct list_head node; /* 0 16 */
} __attribute__((__aligned__(8))); /* 0 24 */
u64 start; /* 24 8 */
u64 end; /* 32 8 */
_Bool erange_warned; /* 40 1 */
/* XXX 3 bytes hole, try to pack */
u32 priv; /* 44 4 */
u32 prot; /* 48 4 */
u32 flags; /* 52 4 */
u64 pgoff; /* 56 8 */
/* --- cacheline 1 boundary (64 bytes) --- */
u64 reloc; /* 64 8 */
u32 maj; /* 72 4 */
u32 min; /* 76 4 */
u64 ino; /* 80 8 */
u64 ino_generation; /* 88 8 */
u64 (*map_ip)(struct map *, u64); /* 96 8 */
u64 (*unmap_ip)(struct map *, u64); /* 104 8 */
struct dso * dso; /* 112 8 */
refcount_t refcnt; /* 120 4 */
/* size: 128, cachelines: 2, members: 17 */
/* sum members: 121, holes: 1, sum holes: 3 */
/* padding: 4 */
/* forced alignments: 1 */
} __attribute__((__aligned__(8)));
$
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: https://lkml.kernel.org/n/tip-bvr8fqfgzxtgnhnwt5sssx5g@xxxxxxxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/tests/map_groups.c | 2 +-
tools/perf/util/map.c | 30 ------------------------------
tools/perf/util/map.h | 1 -
tools/perf/util/map_groups.h | 1 -
tools/perf/util/symbol.c | 16 ++--------------
5 files changed, 3 insertions(+), 47 deletions(-)
diff --git a/tools/perf/tests/map_groups.c b/tools/perf/tests/map_groups.c
index b52adad55f8d..6b9f1cdcbe5b 100644
--- a/tools/perf/tests/map_groups.c
+++ b/tools/perf/tests/map_groups.c
@@ -25,7 +25,7 @@ static int check_maps(struct map_def *merged, unsigned int size, struct map_grou
TEST_ASSERT_VAL("wrong map start", map->start == merged[i].start);
TEST_ASSERT_VAL("wrong map end", map->end == merged[i].end);
TEST_ASSERT_VAL("wrong map name", !strcmp(map->dso->name, merged[i].name));
- TEST_ASSERT_VAL("wrong map refcnt", refcount_read(&map->refcnt) == 2);
+ TEST_ASSERT_VAL("wrong map refcnt", refcount_read(&map->refcnt) == 1);
i++;
}
diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c
index 69b9e9b3d915..49e353eaa337 100644
--- a/tools/perf/util/map.c
+++ b/tools/perf/util/map.c
@@ -26,7 +26,6 @@
#include "ui/ui.h"
static void __maps__insert(struct maps *maps, struct map *map);
-static void __maps__insert_name(struct maps *maps, struct map *map);
static inline int is_anon_memory(const char *filename, u32 flags)
{
@@ -566,7 +565,6 @@ u64 map__objdump_2mem(struct map *map, u64 ip)
static void maps__init(struct maps *maps)
{
maps->entries = RB_ROOT;
- maps->names = RB_ROOT;
init_rwsem(&maps->lock);
}
@@ -589,8 +587,6 @@ static void __maps__purge(struct maps *maps)
maps__for_each_entry_safe(maps, pos, next) {
rb_erase_init(&pos->rb_node, &maps->entries);
map__put(pos);
- rb_erase_init(&pos->rb_node_name, &maps->names);
- map__put(pos);
}
}
@@ -736,7 +732,6 @@ size_t map_groups__fprintf(struct map_groups *mg, FILE *fp)
static void __map_groups__insert(struct map_groups *mg, struct map *map)
{
__maps__insert(&mg->maps, map);
- __maps__insert_name(&mg->maps, map);
}
int map_groups__fixup_overlappings(struct map_groups *mg, struct map *map, FILE *fp)
@@ -893,32 +888,10 @@ static void __maps__insert(struct maps *maps, struct map *map)
map__get(map);
}
-static void __maps__insert_name(struct maps *maps, struct map *map)
-{
- struct rb_node **p = &maps->names.rb_node;
- struct rb_node *parent = NULL;
- struct map *m;
- int rc;
-
- while (*p != NULL) {
- parent = *p;
- m = rb_entry(parent, struct map, rb_node_name);
- rc = strcmp(m->dso->short_name, map->dso->short_name);
- if (rc < 0)
- p = &(*p)->rb_left;
- else
- p = &(*p)->rb_right;
- }
- rb_link_node(&map->rb_node_name, parent, p);
- rb_insert_color(&map->rb_node_name, &maps->names);
- map__get(map);
-}
-
void maps__insert(struct maps *maps, struct map *map)
{
down_write(&maps->lock);
__maps__insert(maps, map);
- __maps__insert_name(maps, map);
up_write(&maps->lock);
}
@@ -926,9 +899,6 @@ static void __maps__remove(struct maps *maps, struct map *map)
{
rb_erase_init(&map->rb_node, &maps->entries);
map__put(map);
-
- rb_erase_init(&map->rb_node_name, &maps->names);
- map__put(map);
}
void maps__remove(struct maps *maps, struct map *map)
diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h
index 365deb6375ab..a31e80991189 100644
--- a/tools/perf/util/map.h
+++ b/tools/perf/util/map.h
@@ -23,7 +23,6 @@ struct map {
struct rb_node rb_node;
struct list_head node;
};
- struct rb_node rb_node_name;
u64 start;
u64 end;
bool erange_warned;
diff --git a/tools/perf/util/map_groups.h b/tools/perf/util/map_groups.h
index 3f361405a4d4..26fc68bd4f60 100644
--- a/tools/perf/util/map_groups.h
+++ b/tools/perf/util/map_groups.h
@@ -16,7 +16,6 @@ struct thread;
struct maps {
struct rb_root entries;
- struct rb_root names;
struct rw_semaphore lock;
};
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 88f4cfbdb69a..0fb9bd8bcf0d 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1764,24 +1764,12 @@ struct map *map_groups__find_by_name(struct map_groups *mg, const char *name)
{
struct maps *maps = &mg->maps;
struct map *map;
- struct rb_node *node;
down_read(&maps->lock);
- for (node = maps->names.rb_node; node; ) {
- int rc;
-
- map = rb_entry(node, struct map, rb_node_name);
-
- rc = strcmp(map->dso->short_name, name);
- if (rc < 0)
- node = node->rb_left;
- else if (rc > 0)
- node = node->rb_right;
- else
-
+ maps__for_each_entry(maps, map)
+ if (strcmp(map->dso->short_name, name) == 0)
goto out_unlock;
- }
map = NULL;
--
2.21.0