[tip: perf/core] perf maps: Do not use an rbtree to sort by map name
From: tip-bot2 for Arnaldo Carvalho de Melo
Date: Tue Nov 19 2019 - 11:58:40 EST
The following commit has been merged into the perf/core branch of tip:
Commit-ID: c5c584d2dbb0883f1e6f61872964a4a3a35a2017
Gitweb: https://git.kernel.org/tip/c5c584d2dbb0883f1e6f61872964a4a3a35a2017
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Wed, 13 Nov 2019 16:16:25 -03:00
Committer: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
CommitterDate: Mon, 18 Nov 2019 11:19:51 -03:00
perf maps: Do not use an rbtree to sort by map name
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 b52adad..6b9f1cd 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 69b9e9b..49e353e 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 365deb6..a31e809 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 3f36140..26fc68b 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 88f4cfb..0fb9bd8 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;