1
linux/tools/perf/util/map.c

235 lines
4.9 KiB
C
Raw Normal View History

#include "symbol.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "debug.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;
}
static int strcommon(const char *pathname, char *cwd, int cwdlen)
{
int n = 0;
while (n < cwdlen && pathname[n] == cwd[n])
++n;
return n;
}
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);
}
struct map *map__new(u64 start, u64 len, u64 pgoff, u32 pid, char *filename,
enum map_type type, char *cwd, int cwdlen)
{
struct map *self = malloc(sizeof(*self));
if (self != NULL) {
char newfilename[PATH_MAX];
struct dso *dso;
int anon;
if (cwd) {
int n = strcommon(filename, cwd, cwdlen);
if (n == cwdlen) {
snprintf(newfilename, sizeof(newfilename),
".%s", filename + n);
filename = newfilename;
}
}
anon = is_anon_memory(filename);
if (anon) {
snprintf(newfilename, sizeof(newfilename), "/tmp/perf-%d.map", pid);
filename = newfilename;
}
dso = dsos__findnew(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);
}
perf annotate: Fix it for non-prelinked *.so The problem was we were incorrectly calculating objdump addresses for sym->start and sym->end, look: For simple ET_DYN type DSO (*.so) with one function, objdump -dS output is something like this: 000004ac <my_strlen>: int my_strlen(const char *s) 4ac: 55 push %ebp 4ad: 89 e5 mov %esp,%ebp 4af: 83 ec 10 sub $0x10,%esp { i.e. we have relative-to-dso-mapping IPs (=RIP) there. For ET_EXEC type and probably for prelinked libs as well (sorry can't test - I don't use prelink) objdump outputs absolute IPs, e.g. 08048604 <zz_strlen>: extern "C" int zz_strlen(const char *s) 8048604: 55 push %ebp 8048605: 89 e5 mov %esp,%ebp 8048607: 83 ec 10 sub $0x10,%esp { So, if sym->start is always relative to dso mapping(*), we'll have to unmap it for ET_EXEC like cases, and leave as is for ET_DYN cases. (*) and it is - we've explicitely made it relative. Look for adjust_symbols handling in dso__load_sym() Previously we were always unmapping sym->start and for ET_DYN dsos resulting addresses were wrong, and so objdump output was empty. The end result was that perf annotate output for symbols from non-prelinked *.so had always 0.00% percents only, which is wrong. To fix it, let's introduce a helper for converting rip to objdump address, and also let's document what map_ip() and unmap_ip() do -- I had to study sources for several hours to understand it. Signed-off-by: Kirill Smelkov <kirr@landau.phys.spbu.ru> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <1265223128-11786-8-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-03 11:52:07 -07:00
/*
* 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;
}
perf top: Fix annotate for userspace First, for programs and prelinked libraries, annotate code was fooled by objdump output IPs (src->eip in the code) being wrongly converted to absolute IPs. In such case there were no conversion needed, but in src->eip = strtoull(src->line, NULL, 16); src->eip = map->unmap_ip(map, src->eip); // = eip + map->start - map->pgoff we were reading absolute address from objdump (e.g. 8048604) and then almost doubling it, because eip & map->start are approximately close for small programs. Needless to say, that later, in record_precise_ip() there was no matching with real runtime IPs. And second, like with `perf annotate` the problem with non-prelinked *.so was that we were doing rip -> objdump address conversion wrong. Also, because unlike `perf annotate`, `perf top` code does annotation based on absolute IPs for performance reasons(*), new helper for mapping objdump addresse to IP is introduced. (*) we get samples info in absolute IPs, and since we do lots of hit-testing on absolute IPs at runtime in record_precise_ip(), it's better to convert objdump addresses to IPs once and do no conversion at runtime. I also had to fix how objdump output is parsed (with hardcoded 8/16 characters format, which was inappropriate for ET_DYN dsos with small addresses like '4ac') Also note, that not all objdump output lines has associtated IPs, e.g. look at source lines here: 000004ac <my_strlen>: extern "C" int my_strlen(const char *s) 4ac: 55 push %ebp 4ad: 89 e5 mov %esp,%ebp 4af: 83 ec 10 sub $0x10,%esp { int len = 0; 4b2: c7 45 fc 00 00 00 00 movl $0x0,-0x4(%ebp) 4b9: eb 08 jmp 4c3 <my_strlen+0x17> while (*s) { ++len; 4bb: 83 45 fc 01 addl $0x1,-0x4(%ebp) ++s; 4bf: 83 45 08 01 addl $0x1,0x8(%ebp) So we mark them with eip=0, and ignore such lines in annotate lookup code. Signed-off-by: Kirill Smelkov <kirr@landau.phys.spbu.ru> [ Note: one hunk of this patch was applied by Mike in 57d8188 ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <1265550376-12665-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2010-02-07 06:46:15 -07:00
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;
}