linux/tools/perf/util/map.c
Arnaldo Carvalho de Melo 0a1eae391d perf tools: Don't keep unreferenced maps when unmaps are detected
For a file with:

[root@emilia linux-2.6-tip]# perf report -D -fi allmodconfig-j32.perf.data | grep events:
     TOTAL events:      36933
      MMAP events:       9056
      LOST events:          0
      COMM events:       1702
      EXIT events:       1887
  THROTTLE events:          8
UNTHROTTLE events:          8
      FORK events:       1894
      READ events:          0
    SAMPLE events:      22378
      ATTR events:          0
EVENT_TYPE events:          0
TRACING_DATA events:          0
  BUILD_ID events:          0
[root@emilia linux-2.6-tip]#

Testing with valgrind and making perf_session__delete() a nop, so that
we can notice how many maps were actually deleted due to not having any
samples on it:

==== HEAP SUMMARY:

Before:

==10339==     in use at exit: 8,909,997 bytes in 68,690 blocks
==10339==   total heap usage: 78,696 allocs, 10,007 frees, 11,925,853 bytes allocated

After:

==10506==     in use at exit: 8,902,605 bytes in 68,606 blocks
==10506==   total heap usage: 78,696 allocs, 10,091 frees, 11,925,853 bytes allocated

I.e. just 84 detected unmaps with no hits out of 9056 for this workload,
not much, but in some other long running workload this may save more
bytes.

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2010-08-02 19:45:23 -03:00

683 lines
15 KiB
C

#include "symbol.h"
#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include "map.h"
const char *map_type__name[MAP__NR_TYPES] = {
[MAP__FUNCTION] = "Functions",
[MAP__VARIABLE] = "Variables",
};
static inline int is_anon_memory(const char *filename)
{
return strcmp(filename, "//anon") == 0;
}
void map__init(struct map *self, enum map_type type,
u64 start, u64 end, u64 pgoff, struct dso *dso)
{
self->type = type;
self->start = start;
self->end = end;
self->pgoff = pgoff;
self->dso = dso;
self->map_ip = map__map_ip;
self->unmap_ip = map__unmap_ip;
RB_CLEAR_NODE(&self->rb_node);
self->groups = NULL;
self->referenced = false;
}
struct map *map__new(struct list_head *dsos__list, u64 start, u64 len,
u64 pgoff, u32 pid, char *filename,
enum map_type type)
{
struct map *self = malloc(sizeof(*self));
if (self != NULL) {
char newfilename[PATH_MAX];
struct dso *dso;
int anon;
anon = is_anon_memory(filename);
if (anon) {
snprintf(newfilename, sizeof(newfilename), "/tmp/perf-%d.map", pid);
filename = newfilename;
}
dso = __dsos__findnew(dsos__list, filename);
if (dso == NULL)
goto out_delete;
map__init(self, type, start, start + len, pgoff, dso);
if (anon) {
set_identity:
self->map_ip = self->unmap_ip = identity__map_ip;
} else if (strcmp(filename, "[vdso]") == 0) {
dso__set_loaded(dso, self->type);
goto set_identity;
}
}
return self;
out_delete:
free(self);
return NULL;
}
void map__delete(struct map *self)
{
free(self);
}
void map__fixup_start(struct map *self)
{
struct rb_root *symbols = &self->dso->symbols[self->type];
struct rb_node *nd = rb_first(symbols);
if (nd != NULL) {
struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
self->start = sym->start;
}
}
void map__fixup_end(struct map *self)
{
struct rb_root *symbols = &self->dso->symbols[self->type];
struct rb_node *nd = rb_last(symbols);
if (nd != NULL) {
struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
self->end = sym->end;
}
}
#define DSO__DELETED "(deleted)"
int map__load(struct map *self, symbol_filter_t filter)
{
const char *name = self->dso->long_name;
int nr;
if (dso__loaded(self->dso, self->type))
return 0;
nr = dso__load(self->dso, self, filter);
if (nr < 0) {
if (self->dso->has_build_id) {
char sbuild_id[BUILD_ID_SIZE * 2 + 1];
build_id__sprintf(self->dso->build_id,
sizeof(self->dso->build_id),
sbuild_id);
pr_warning("%s with build id %s not found",
name, sbuild_id);
} else
pr_warning("Failed to open %s", name);
pr_warning(", continuing without symbols\n");
return -1;
} else if (nr == 0) {
const size_t len = strlen(name);
const size_t real_len = len - sizeof(DSO__DELETED);
if (len > sizeof(DSO__DELETED) &&
strcmp(name + real_len + 1, DSO__DELETED) == 0) {
pr_warning("%.*s was updated, restart the long "
"running apps that use it!\n",
(int)real_len, name);
} else {
pr_warning("no symbols found in %s, maybe install "
"a debug package?\n", name);
}
return -1;
}
/*
* Only applies to the kernel, as its symtabs aren't relative like the
* module ones.
*/
if (self->dso->kernel)
map__reloc_vmlinux(self);
return 0;
}
struct symbol *map__find_symbol(struct map *self, u64 addr,
symbol_filter_t filter)
{
if (map__load(self, filter) < 0)
return NULL;
return dso__find_symbol(self->dso, self->type, addr);
}
struct symbol *map__find_symbol_by_name(struct map *self, const char *name,
symbol_filter_t filter)
{
if (map__load(self, filter) < 0)
return NULL;
if (!dso__sorted_by_name(self->dso, self->type))
dso__sort_by_name(self->dso, self->type);
return dso__find_symbol_by_name(self->dso, self->type, name);
}
struct map *map__clone(struct map *self)
{
struct map *map = malloc(sizeof(*self));
if (!map)
return NULL;
memcpy(map, self, sizeof(*self));
return map;
}
int map__overlap(struct map *l, struct map *r)
{
if (l->start > r->start) {
struct map *t = l;
l = r;
r = t;
}
if (l->end > r->start)
return 1;
return 0;
}
size_t map__fprintf(struct map *self, FILE *fp)
{
return fprintf(fp, " %Lx-%Lx %Lx %s\n",
self->start, self->end, self->pgoff, self->dso->name);
}
/*
* objdump wants/reports absolute IPs for ET_EXEC, and RIPs for ET_DYN.
* map->dso->adjust_symbols==1 for ET_EXEC-like cases.
*/
u64 map__rip_2objdump(struct map *map, u64 rip)
{
u64 addr = map->dso->adjust_symbols ?
map->unmap_ip(map, rip) : /* RIP -> IP */
rip;
return addr;
}
u64 map__objdump_2ip(struct map *map, u64 addr)
{
u64 ip = map->dso->adjust_symbols ?
addr :
map->unmap_ip(map, addr); /* RIP -> IP */
return ip;
}
void map_groups__init(struct map_groups *self)
{
int i;
for (i = 0; i < MAP__NR_TYPES; ++i) {
self->maps[i] = RB_ROOT;
INIT_LIST_HEAD(&self->removed_maps[i]);
}
self->machine = NULL;
}
static void maps__delete(struct rb_root *self)
{
struct rb_node *next = rb_first(self);
while (next) {
struct map *pos = rb_entry(next, struct map, rb_node);
next = rb_next(&pos->rb_node);
rb_erase(&pos->rb_node, self);
map__delete(pos);
}
}
static void maps__delete_removed(struct list_head *self)
{
struct map *pos, *n;
list_for_each_entry_safe(pos, n, self, node) {
list_del(&pos->node);
map__delete(pos);
}
}
void map_groups__exit(struct map_groups *self)
{
int i;
for (i = 0; i < MAP__NR_TYPES; ++i) {
maps__delete(&self->maps[i]);
maps__delete_removed(&self->removed_maps[i]);
}
}
void map_groups__flush(struct map_groups *self)
{
int type;
for (type = 0; type < MAP__NR_TYPES; type++) {
struct rb_root *root = &self->maps[type];
struct rb_node *next = rb_first(root);
while (next) {
struct map *pos = rb_entry(next, struct map, rb_node);
next = rb_next(&pos->rb_node);
rb_erase(&pos->rb_node, root);
/*
* We may have references to this map, for
* instance in some hist_entry instances, so
* just move them to a separate list.
*/
list_add_tail(&pos->node, &self->removed_maps[pos->type]);
}
}
}
struct symbol *map_groups__find_symbol(struct map_groups *self,
enum map_type type, u64 addr,
struct map **mapp,
symbol_filter_t filter)
{
struct map *map = map_groups__find(self, type, addr);
if (map != NULL) {
if (mapp != NULL)
*mapp = map;
return map__find_symbol(map, map->map_ip(map, addr), filter);
}
return NULL;
}
struct symbol *map_groups__find_symbol_by_name(struct map_groups *self,
enum map_type type,
const char *name,
struct map **mapp,
symbol_filter_t filter)
{
struct rb_node *nd;
for (nd = rb_first(&self->maps[type]); nd; nd = rb_next(nd)) {
struct map *pos = rb_entry(nd, struct map, rb_node);
struct symbol *sym = map__find_symbol_by_name(pos, name, filter);
if (sym == NULL)
continue;
if (mapp != NULL)
*mapp = pos;
return sym;
}
return NULL;
}
size_t __map_groups__fprintf_maps(struct map_groups *self,
enum map_type type, int verbose, FILE *fp)
{
size_t printed = fprintf(fp, "%s:\n", map_type__name[type]);
struct rb_node *nd;
for (nd = rb_first(&self->maps[type]); nd; nd = rb_next(nd)) {
struct map *pos = rb_entry(nd, struct map, rb_node);
printed += fprintf(fp, "Map:");
printed += map__fprintf(pos, fp);
if (verbose > 2) {
printed += dso__fprintf(pos->dso, type, fp);
printed += fprintf(fp, "--\n");
}
}
return printed;
}
size_t map_groups__fprintf_maps(struct map_groups *self, int verbose, FILE *fp)
{
size_t printed = 0, i;
for (i = 0; i < MAP__NR_TYPES; ++i)
printed += __map_groups__fprintf_maps(self, i, verbose, fp);
return printed;
}
static size_t __map_groups__fprintf_removed_maps(struct map_groups *self,
enum map_type type,
int verbose, FILE *fp)
{
struct map *pos;
size_t printed = 0;
list_for_each_entry(pos, &self->removed_maps[type], node) {
printed += fprintf(fp, "Map:");
printed += map__fprintf(pos, fp);
if (verbose > 1) {
printed += dso__fprintf(pos->dso, type, fp);
printed += fprintf(fp, "--\n");
}
}
return printed;
}
static size_t map_groups__fprintf_removed_maps(struct map_groups *self,
int verbose, FILE *fp)
{
size_t printed = 0, i;
for (i = 0; i < MAP__NR_TYPES; ++i)
printed += __map_groups__fprintf_removed_maps(self, i, verbose, fp);
return printed;
}
size_t map_groups__fprintf(struct map_groups *self, int verbose, FILE *fp)
{
size_t printed = map_groups__fprintf_maps(self, verbose, fp);
printed += fprintf(fp, "Removed maps:\n");
return printed + map_groups__fprintf_removed_maps(self, verbose, fp);
}
int map_groups__fixup_overlappings(struct map_groups *self, struct map *map,
int verbose, FILE *fp)
{
struct rb_root *root = &self->maps[map->type];
struct rb_node *next = rb_first(root);
int err = 0;
while (next) {
struct map *pos = rb_entry(next, struct map, rb_node);
next = rb_next(&pos->rb_node);
if (!map__overlap(pos, map))
continue;
if (verbose >= 2) {
fputs("overlapping maps:\n", fp);
map__fprintf(map, fp);
map__fprintf(pos, fp);
}
rb_erase(&pos->rb_node, root);
/*
* Now check if we need to create new maps for areas not
* overlapped by the new map:
*/
if (map->start > pos->start) {
struct map *before = map__clone(pos);
if (before == NULL) {
err = -ENOMEM;
goto move_map;
}
before->end = map->start - 1;
map_groups__insert(self, before);
if (verbose >= 2)
map__fprintf(before, fp);
}
if (map->end < pos->end) {
struct map *after = map__clone(pos);
if (after == NULL) {
err = -ENOMEM;
goto move_map;
}
after->start = map->end + 1;
map_groups__insert(self, after);
if (verbose >= 2)
map__fprintf(after, fp);
}
move_map:
/*
* If we have references, just move them to a separate list.
*/
if (pos->referenced)
list_add_tail(&pos->node, &self->removed_maps[map->type]);
else
map__delete(pos);
if (err)
return err;
}
return 0;
}
/*
* XXX This should not really _copy_ te maps, but refcount them.
*/
int map_groups__clone(struct map_groups *self,
struct map_groups *parent, enum map_type type)
{
struct rb_node *nd;
for (nd = rb_first(&parent->maps[type]); nd; nd = rb_next(nd)) {
struct map *map = rb_entry(nd, struct map, rb_node);
struct map *new = map__clone(map);
if (new == NULL)
return -ENOMEM;
map_groups__insert(self, new);
}
return 0;
}
static u64 map__reloc_map_ip(struct map *map, u64 ip)
{
return ip + (s64)map->pgoff;
}
static u64 map__reloc_unmap_ip(struct map *map, u64 ip)
{
return ip - (s64)map->pgoff;
}
void map__reloc_vmlinux(struct map *self)
{
struct kmap *kmap = map__kmap(self);
s64 reloc;
if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->unrelocated_addr)
return;
reloc = (kmap->ref_reloc_sym->unrelocated_addr -
kmap->ref_reloc_sym->addr);
if (!reloc)
return;
self->map_ip = map__reloc_map_ip;
self->unmap_ip = map__reloc_unmap_ip;
self->pgoff = reloc;
}
void maps__insert(struct rb_root *maps, struct map *map)
{
struct rb_node **p = &maps->rb_node;
struct rb_node *parent = NULL;
const u64 ip = map->start;
struct map *m;
while (*p != NULL) {
parent = *p;
m = rb_entry(parent, struct map, rb_node);
if (ip < m->start)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
rb_link_node(&map->rb_node, parent, p);
rb_insert_color(&map->rb_node, maps);
}
void maps__remove(struct rb_root *self, struct map *map)
{
rb_erase(&map->rb_node, self);
}
struct map *maps__find(struct rb_root *maps, u64 ip)
{
struct rb_node **p = &maps->rb_node;
struct rb_node *parent = NULL;
struct map *m;
while (*p != NULL) {
parent = *p;
m = rb_entry(parent, struct map, rb_node);
if (ip < m->start)
p = &(*p)->rb_left;
else if (ip > m->end)
p = &(*p)->rb_right;
else
return m;
}
return NULL;
}
int machine__init(struct machine *self, const char *root_dir, pid_t pid)
{
map_groups__init(&self->kmaps);
RB_CLEAR_NODE(&self->rb_node);
INIT_LIST_HEAD(&self->user_dsos);
INIT_LIST_HEAD(&self->kernel_dsos);
self->kmaps.machine = self;
self->pid = pid;
self->root_dir = strdup(root_dir);
return self->root_dir == NULL ? -ENOMEM : 0;
}
static void dsos__delete(struct list_head *self)
{
struct dso *pos, *n;
list_for_each_entry_safe(pos, n, self, node) {
list_del(&pos->node);
dso__delete(pos);
}
}
void machine__exit(struct machine *self)
{
map_groups__exit(&self->kmaps);
dsos__delete(&self->user_dsos);
dsos__delete(&self->kernel_dsos);
free(self->root_dir);
self->root_dir = NULL;
}
void machine__delete(struct machine *self)
{
machine__exit(self);
free(self);
}
struct machine *machines__add(struct rb_root *self, pid_t pid,
const char *root_dir)
{
struct rb_node **p = &self->rb_node;
struct rb_node *parent = NULL;
struct machine *pos, *machine = malloc(sizeof(*machine));
if (!machine)
return NULL;
if (machine__init(machine, root_dir, pid) != 0) {
free(machine);
return NULL;
}
while (*p != NULL) {
parent = *p;
pos = rb_entry(parent, struct machine, rb_node);
if (pid < pos->pid)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
rb_link_node(&machine->rb_node, parent, p);
rb_insert_color(&machine->rb_node, self);
return machine;
}
struct machine *machines__find(struct rb_root *self, pid_t pid)
{
struct rb_node **p = &self->rb_node;
struct rb_node *parent = NULL;
struct machine *machine;
struct machine *default_machine = NULL;
while (*p != NULL) {
parent = *p;
machine = rb_entry(parent, struct machine, rb_node);
if (pid < machine->pid)
p = &(*p)->rb_left;
else if (pid > machine->pid)
p = &(*p)->rb_right;
else
return machine;
if (!machine->pid)
default_machine = machine;
}
return default_machine;
}
struct machine *machines__findnew(struct rb_root *self, pid_t pid)
{
char path[PATH_MAX];
const char *root_dir;
struct machine *machine = machines__find(self, pid);
if (!machine || machine->pid != pid) {
if (pid == HOST_KERNEL_ID || pid == DEFAULT_GUEST_KERNEL_ID)
root_dir = "";
else {
if (!symbol_conf.guestmount)
goto out;
sprintf(path, "%s/%d", symbol_conf.guestmount, pid);
if (access(path, R_OK)) {
pr_err("Can't access file %s\n", path);
goto out;
}
root_dir = path;
}
machine = machines__add(self, pid, root_dir);
}
out:
return machine;
}
void machines__process(struct rb_root *self, machine__process_t process, void *data)
{
struct rb_node *nd;
for (nd = rb_first(self); nd; nd = rb_next(nd)) {
struct machine *pos = rb_entry(nd, struct machine, rb_node);
process(pos, data);
}
}
char *machine__mmap_name(struct machine *self, char *bf, size_t size)
{
if (machine__is_host(self))
snprintf(bf, size, "[%s]", "kernel.kallsyms");
else if (machine__is_default_guest(self))
snprintf(bf, size, "[%s]", "guest.kernel.kallsyms");
else
snprintf(bf, size, "[%s.%d]", "guest.kernel.kallsyms", self->pid);
return bf;
}