perf symbols: Add interface to read DSO image data

Adding following interface for DSO object to allow
reading of DSO image data:

  dso__data_fd
    - opens DSO and returns file descriptor
      Binary types are used to locate/open DSO in following order:
        DSO_BINARY_TYPE__BUILD_ID_CACHE
        DSO_BINARY_TYPE__SYSTEM_PATH_DSO
      In other word we first try to open DSO build-id path,
      and if that fails we try to open DSO system path.

  dso__data_read_offset
    - reads DSO data from specified offset

  dso__data_read_addr
    - reads DSO data from specified address/map.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arun Sharma <asharma@fb.com>
Cc: Benjamin Redelings <benjamin.redelings@nescent.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Cc: Ulrich Drepper <drepper@gmail.com>
Link: http://lkml.kernel.org/r/1342959280-5361-11-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Jiri Olsa 2012-07-22 14:14:33 +02:00 committed by Arnaldo Carvalho de Melo
parent 44f24cb315
commit 949d160b69
2 changed files with 117 additions and 0 deletions

View file

@ -65,6 +65,14 @@ static enum dso_binary_type binary_type_symtab[] = {
#define DSO_BINARY_TYPE__SYMTAB_CNT sizeof(binary_type_symtab)
static enum dso_binary_type binary_type_data[] = {
DSO_BINARY_TYPE__BUILD_ID_CACHE,
DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
DSO_BINARY_TYPE__NOT_FOUND,
};
#define DSO_BINARY_TYPE__DATA_CNT sizeof(binary_type_data)
int dso__name_len(const struct dso *dso)
{
if (!dso)
@ -336,6 +344,7 @@ struct dso *dso__new(const char *name)
for (i = 0; i < MAP__NR_TYPES; ++i)
dso->symbols[i] = dso->symbol_names[i] = RB_ROOT;
dso->symtab_type = DSO_BINARY_TYPE__NOT_FOUND;
dso->data_type = DSO_BINARY_TYPE__NOT_FOUND;
dso->loaded = 0;
dso->sorted_by_name = 0;
dso->has_build_id = 0;
@ -2953,3 +2962,103 @@ struct map *dso__new_map(const char *name)
return map;
}
static int open_dso(struct dso *dso, struct machine *machine)
{
char *root_dir = (char *) "";
char *name;
int fd;
name = malloc(PATH_MAX);
if (!name)
return -ENOMEM;
if (machine)
root_dir = machine->root_dir;
if (dso__binary_type_file(dso, dso->data_type,
root_dir, name, PATH_MAX)) {
free(name);
return -EINVAL;
}
fd = open(name, O_RDONLY);
free(name);
return fd;
}
int dso__data_fd(struct dso *dso, struct machine *machine)
{
int i = 0;
if (dso->data_type != DSO_BINARY_TYPE__NOT_FOUND)
return open_dso(dso, machine);
do {
int fd;
dso->data_type = binary_type_data[i++];
fd = open_dso(dso, machine);
if (fd >= 0)
return fd;
} while (dso->data_type != DSO_BINARY_TYPE__NOT_FOUND);
return -EINVAL;
}
static ssize_t dso_cache_read(struct dso *dso __used, u64 offset __used,
u8 *data __used, ssize_t size __used)
{
return -EINVAL;
}
static int dso_cache_add(struct dso *dso __used, u64 offset __used,
u8 *data __used, ssize_t size __used)
{
return 0;
}
static ssize_t read_dso_data(struct dso *dso, struct machine *machine,
u64 offset, u8 *data, ssize_t size)
{
ssize_t rsize = -1;
int fd;
fd = dso__data_fd(dso, machine);
if (fd < 0)
return -1;
do {
if (-1 == lseek(fd, offset, SEEK_SET))
break;
rsize = read(fd, data, size);
if (-1 == rsize)
break;
if (dso_cache_add(dso, offset, data, size))
pr_err("Failed to add data int dso cache.");
} while (0);
close(fd);
return rsize;
}
ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
u64 offset, u8 *data, ssize_t size)
{
if (dso_cache_read(dso, offset, data, size))
return read_dso_data(dso, machine, offset, data, size);
return 0;
}
ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
struct machine *machine, u64 addr,
u8 *data, ssize_t size)
{
u64 offset = map->map_ip(map, addr);
return dso__data_read_offset(dso, machine, offset, data, size);
}

View file

@ -189,6 +189,7 @@ struct dso {
enum dso_kernel_type kernel;
enum dso_swap_type needs_swap;
enum dso_binary_type symtab_type;
enum dso_binary_type data_type;
u8 adjust_symbols:1;
u8 has_build_id:1;
u8 hit:1;
@ -306,4 +307,11 @@ size_t machine__fprintf_vmlinux_path(struct machine *machine, FILE *fp);
int dso__binary_type_file(struct dso *dso, enum dso_binary_type type,
char *root_dir, char *file, size_t size);
int dso__data_fd(struct dso *dso, struct machine *machine);
ssize_t dso__data_read_offset(struct dso *dso, struct machine *machine,
u64 offset, u8 *data, ssize_t size);
ssize_t dso__data_read_addr(struct dso *dso, struct map *map,
struct machine *machine, u64 addr,
u8 *data, ssize_t size);
#endif /* __PERF_SYMBOL */