kernel-fxtec-pro1x/tools/perf/util/map.h
Kirill Smelkov ee11b90b12 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 17:30:20 +01:00

92 lines
2.1 KiB
C

#ifndef __PERF_MAP_H
#define __PERF_MAP_H
#include <linux/compiler.h>
#include <linux/list.h>
#include <linux/rbtree.h>
#include <linux/types.h>
enum map_type {
MAP__FUNCTION = 0,
MAP__VARIABLE,
};
#define MAP__NR_TYPES (MAP__VARIABLE + 1)
struct dso;
struct ref_reloc_sym;
struct map_groups;
struct map {
union {
struct rb_node rb_node;
struct list_head node;
};
u64 start;
u64 end;
enum map_type type;
u64 pgoff;
/* ip -> dso rip */
u64 (*map_ip)(struct map *, u64);
/* dso rip -> ip */
u64 (*unmap_ip)(struct map *, u64);
struct dso *dso;
};
struct kmap {
struct ref_reloc_sym *ref_reloc_sym;
struct map_groups *kmaps;
};
static inline struct kmap *map__kmap(struct map *self)
{
return (struct kmap *)(self + 1);
}
static inline u64 map__map_ip(struct map *map, u64 ip)
{
return ip - map->start + map->pgoff;
}
static inline u64 map__unmap_ip(struct map *map, u64 ip)
{
return ip + map->start - map->pgoff;
}
static inline u64 identity__map_ip(struct map *map __used, u64 ip)
{
return ip;
}
/* rip/ip <-> addr suitable for passing to `objdump --start-address=` */
u64 map__rip_2objdump(struct map *map, u64 rip);
u64 map__objdump_2ip(struct map *map, u64 addr);
struct symbol;
struct mmap_event;
typedef int (*symbol_filter_t)(struct map *map, struct symbol *sym);
void map__init(struct map *self, enum map_type type,
u64 start, u64 end, u64 pgoff, struct dso *dso);
struct map *map__new(struct mmap_event *event, enum map_type,
char *cwd, int cwdlen);
void map__delete(struct map *self);
struct map *map__clone(struct map *self);
int map__overlap(struct map *l, struct map *r);
size_t map__fprintf(struct map *self, FILE *fp);
int map__load(struct map *self, symbol_filter_t filter);
struct symbol *map__find_symbol(struct map *self,
u64 addr, symbol_filter_t filter);
struct symbol *map__find_symbol_by_name(struct map *self, const char *name,
symbol_filter_t filter);
void map__fixup_start(struct map *self);
void map__fixup_end(struct map *self);
void map__reloc_vmlinux(struct map *self);
#endif /* __PERF_MAP_H */