redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

perf probe: Show appropriate symbol for ref_reloc_sym based kprobes

Browse source 
Show appropriate symbol for ref_reloc_sym based kprobes instead of
refpoint+offset when perf-probe -l runs without debuginfo.

Without this change:
  # ./perf probe -l
    probe:t_show         (on _stext+889880 with m v)
    probe:t_show_1       (on _stext+928568 with m v t)
    probe:t_show_2       (on _stext+969512 with m v fmt)
    probe:t_show_3       (on _stext+1001416 with m v file)

With this change:
  # ./perf probe -l
    probe:t_show         (on t_show with m v)
    probe:t_show_1       (on t_show with m v t)
    probe:t_show_2       (on t_show with m v fmt)
    probe:t_show_3       (on t_show with m v file)

Changes from v2:
 - Check ref_reloc_sym to find correct unrelocated address.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: "David A. Long" <dave.long@linaro.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: yrl.pp-manager.tt@hitachi.com
Link: http://lkml.kernel.org/r/20140206053220.29635.81819.stgit@kbuild-fedora.yrl.intra.hitachi.co.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Masami Hiramatsu 2014-02-06 05:32:20 +00:00 committed by Arnaldo Carvalho de Melo
parent f90acac757
commit 8f33f7deac
1 changed files with 55 additions and 28 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

83
tools/perf/util/probe-event.c
View file

@ -121,6 +121,42 @@ static struct symbol *__find_kernel_function_by_name(const char *name,
NULL);
}
static struct symbol *__find_kernel_function(u64 addr, struct map **mapp)
{
return machine__find_kernel_function(host_machine, addr, mapp, NULL);
}
static struct ref_reloc_sym *kernel_get_ref_reloc_sym(void)
{
/* kmap->ref_reloc_sym should be set if host_machine is initialized */
struct kmap *kmap;
if (map__load(host_machine->vmlinux_maps[MAP__FUNCTION], NULL) < 0)
return NULL;
kmap = map__kmap(host_machine->vmlinux_maps[MAP__FUNCTION]);
return kmap->ref_reloc_sym;
}
static u64 kernel_get_symbol_address_by_name(const char *name, bool reloc)
{
struct ref_reloc_sym *reloc_sym;
struct symbol *sym;
struct map *map;
/* ref_reloc_sym is just a label. Need a special fix*/
reloc_sym = kernel_get_ref_reloc_sym();
if (reloc_sym && strcmp(name, reloc_sym->name) == 0)
return (reloc) ? reloc_sym->addr : reloc_sym->unrelocated_addr;
else {
sym = __find_kernel_function_by_name(name, &map);
if (sym)
return map->unmap_ip(map, sym->start) -
(reloc) ? 0 : map->reloc;
}
return 0;
}
static struct map *kernel_get_module_map(const char *module)
{
struct rb_node *nd;
@ -216,12 +252,26 @@ out:
static int convert_to_perf_probe_point(struct probe_trace_point *tp,
struct perf_probe_point *pp)
{
pp->function = strdup(tp->symbol);
struct symbol *sym;
struct map *map;
u64 addr = kernel_get_symbol_address_by_name(tp->symbol, true);
if (addr) {
addr += tp->offset;
sym = __find_kernel_function(addr, &map);
if (!sym)
goto failed;
pp->function = strdup(sym->name);
pp->offset = addr - map->unmap_ip(map, sym->start);
} else {
failed:
pp->function = strdup(tp->symbol);
pp->offset = tp->offset;
}
if (pp->function == NULL)
return -ENOMEM;
pp->offset = tp->offset;
pp->retprobe = tp->retprobe;
return 0;
@ -248,18 +298,6 @@ static struct debuginfo *open_debuginfo(const char *module)
return debuginfo__new(path);
}
static struct ref_reloc_sym *__kernel_get_ref_reloc_sym(void)
{
/* kmap->ref_reloc_sym should be set if host_machine is initialized */
struct kmap *kmap;
if (map__load(host_machine->vmlinux_maps[MAP__FUNCTION], NULL) < 0)
return NULL;
kmap = map__kmap(host_machine->vmlinux_maps[MAP__FUNCTION]);
return kmap->ref_reloc_sym;
}
/*
* Convert trace point to probe point with debuginfo
* Currently only handles kprobes.
@ -267,24 +305,13 @@ static struct ref_reloc_sym *__kernel_get_ref_reloc_sym(void)
static int kprobe_convert_to_perf_probe(struct probe_trace_point *tp,
struct perf_probe_point *pp)
{
struct symbol *sym;
struct ref_reloc_sym *reloc_sym;
struct map *map;
u64 addr = 0;
int ret = -ENOENT;
struct debuginfo *dinfo;
/* ref_reloc_sym is just a label. Need a special fix*/
reloc_sym = __kernel_get_ref_reloc_sym();
if (reloc_sym && strcmp(tp->symbol, reloc_sym->name) == 0)
addr = reloc_sym->unrelocated_addr + tp->offset;
else {
sym = __find_kernel_function_by_name(tp->symbol, &map);
if (sym)
addr = map->unmap_ip(map, sym->start + tp->offset) -
map->reloc;
}
addr = kernel_get_symbol_address_by_name(tp->symbol, false);
if (addr) {
addr += tp->offset;
pr_debug("try to find %s+%ld@%" PRIx64 "\n", tp->symbol,
tp->offset, addr);
@ -420,7 +447,7 @@ static int post_process_probe_trace_events(struct probe_trace_event *tevs,
if (module)
return add_module_to_probe_trace_events(tevs, ntevs, module);
reloc_sym = __kernel_get_ref_reloc_sym();
reloc_sym = kernel_get_ref_reloc_sym();
if (!reloc_sym) {
pr_warning("Relocated base symbol is not found!\n");
return -EINVAL;