mirror of
https://github.com/adulau/aha.git
synced 2024-12-28 11:46:19 +00:00
perf tools: Improve kernel/modules symbol lookup
This removes the ovelapping of vmlinux addresses with modules,
using the ELF section name when using --vmlinux and creating a
unique DSO name when using /proc/kallsyms ([kernel].N).
This is done by creating multiple 'struct map' instances for
address ranges backed by DSOs that have just the symbols for that
range and a name that is derived from the ELF section name.o
Now it is possible to ask for just the symbols in some particular
kernel section:
$ perf report -m --vmlinux ../build/tip-recvmmsg/vmlinux \
--dsos [kernel].vsyscall_fn | head -15
52.73% Xorg [.] vread_hpet
18.61% firefox [.] vread_hpet
14.50% npviewer.bin [.] vread_hpet
6.83% compiz [.] vread_hpet
5.73% glxgears [.] vread_hpet
0.63% java [.] vread_hpet
0.30% gnome-terminal [.] vread_hpet
0.23% perf [.] vread_hpet
0.18% xchat [.] vread_hpet
$
Now we don't have to first lookup the list of modules and then, if
it fails, vmlinux symbols, its just a simple lookup for the map
then the symbols, just like for threads.
Reports generated using /proc/kallsyms and --vmlinux should provide
the same results, modulo the DSO name for sections other than
".text".
But they don't right now because things like:
ffffffff81011c20-ffffffff81012068 system_call
ffffffff81011c30-ffffffff81011c9b system_call_after_swapgs
ffffffff81011c9c-ffffffff81011cb6 system_call_fastpath
ffffffff81011cb7-ffffffff81011cbb ret_from_sys_call
I.e. overlapping symbols, again some ASM special case that we have
to fixup.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
LKML-Reference: <1254934136-8503-1-git-send-email-acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Arnaldo Carvalho de Melo
Ingo Molnar
parent
da21d1b547
commit
2e538c4a18
1 changed files with 203 additions and 89 deletions
|
|
@ -26,27 +26,35 @@ enum dso_origin {
|
|||
|
||||
static void dsos__add(struct dso *dso);
|
||||
static struct dso *dsos__find(const char *name);
|
||||
static struct map *map__new2(u64 start, struct dso *dso);
|
||||
static void kernel_maps__insert(struct map *map);
|
||||
|
||||
static struct rb_root kernel_maps;
|
||||
|
||||
static void dso__set_symbols_end(struct dso *self)
|
||||
static void dso__fixup_sym_end(struct dso *self)
|
||||
{
|
||||
struct rb_node *nd, *prevnd = rb_first(&self->syms);
|
||||
struct symbol *curr, *prev;
|
||||
|
||||
if (prevnd == NULL)
|
||||
return;
|
||||
|
||||
curr = rb_entry(prevnd, struct symbol, rb_node);
|
||||
|
||||
for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
|
||||
struct symbol *prev = rb_entry(prevnd, struct symbol, rb_node),
|
||||
*curr = rb_entry(nd, struct symbol, rb_node);
|
||||
prev = curr;
|
||||
curr = rb_entry(nd, struct symbol, rb_node);
|
||||
|
||||
if (prev->end == prev->start)
|
||||
prev->end = curr->start - 1;
|
||||
prevnd = nd;
|
||||
}
|
||||
|
||||
/* Last entry */
|
||||
if (curr->end == curr->start)
|
||||
curr->end = roundup(curr->start, 4096);
|
||||
}
|
||||
|
||||
static void kernel_maps__fixup_sym_end(void)
|
||||
static void kernel_maps__fixup_end(void)
|
||||
{
|
||||
struct map *prev, *curr;
|
||||
struct rb_node *nd, *prevnd = rb_first(&kernel_maps);
|
||||
|
|
@ -55,13 +63,17 @@ static void kernel_maps__fixup_sym_end(void)
|
|||
return;
|
||||
|
||||
curr = rb_entry(prevnd, struct map, rb_node);
|
||||
dso__set_symbols_end(curr->dso);
|
||||
|
||||
for (nd = rb_next(prevnd); nd; nd = rb_next(nd)) {
|
||||
prev = curr;
|
||||
curr = rb_entry(nd, struct map, rb_node);
|
||||
prev->end = curr->start - 1;
|
||||
dso__set_symbols_end(curr->dso);
|
||||
}
|
||||
|
||||
nd = rb_last(&curr->dso->syms);
|
||||
if (nd) {
|
||||
struct symbol *sym = rb_entry(nd, struct symbol, rb_node);
|
||||
curr->end = sym->end;
|
||||
}
|
||||
}
|
||||
|
||||
|
|
@ -200,13 +212,16 @@ size_t dso__fprintf(struct dso *self, FILE *fp)
|
|||
return ret;
|
||||
}
|
||||
|
||||
static int maps__load_kallsyms(symbol_filter_t filter, int use_modules, int v)
|
||||
/*
|
||||
* Loads the function entries in /proc/kallsyms into kernel_map->dso,
|
||||
* so that we can in the next step set the symbol ->end address and then
|
||||
* call kernel_maps__split_kallsyms.
|
||||
*/
|
||||
static int kernel_maps__load_all_kallsyms(int v)
|
||||
{
|
||||
struct map *map = kernel_map;
|
||||
char *line = NULL;
|
||||
size_t n;
|
||||
FILE *file = fopen("/proc/kallsyms", "r");
|
||||
int count = 0;
|
||||
|
||||
if (file == NULL)
|
||||
goto out_failure;
|
||||
|
|
@ -216,7 +231,7 @@ static int maps__load_kallsyms(symbol_filter_t filter, int use_modules, int v)
|
|||
struct symbol *sym;
|
||||
int line_len, len;
|
||||
char symbol_type;
|
||||
char *module, *symbol_name;
|
||||
char *symbol_name;
|
||||
|
||||
line_len = getline(&line, &n, file);
|
||||
if (line_len < 0)
|
||||
|
|
@ -241,20 +256,55 @@ static int maps__load_kallsyms(symbol_filter_t filter, int use_modules, int v)
|
|||
continue;
|
||||
|
||||
symbol_name = line + len + 2;
|
||||
module = strchr(symbol_name, '\t');
|
||||
if (module) {
|
||||
char *module_name_end;
|
||||
/*
|
||||
* Will fix up the end later, when we have all symbols sorted.
|
||||
*/
|
||||
sym = symbol__new(start, 0, symbol_name,
|
||||
kernel_map->dso->sym_priv_size, v);
|
||||
|
||||
if (sym == NULL)
|
||||
goto out_delete_line;
|
||||
|
||||
dso__insert_symbol(kernel_map->dso, sym);
|
||||
}
|
||||
|
||||
free(line);
|
||||
fclose(file);
|
||||
|
||||
return 0;
|
||||
|
||||
out_delete_line:
|
||||
free(line);
|
||||
out_failure:
|
||||
return -1;
|
||||
}
|
||||
|
||||
/*
|
||||
* Split the symbols into maps, making sure there are no overlaps, i.e. the
|
||||
* kernel range is broken in several maps, named [kernel].N, as we don't have
|
||||
* the original ELF section names vmlinux have.
|
||||
*/
|
||||
static int kernel_maps__split_kallsyms(symbol_filter_t filter, int use_modules)
|
||||
{
|
||||
struct map *map = kernel_map;
|
||||
struct symbol *pos;
|
||||
int count = 0;
|
||||
struct rb_node *next = rb_first(&kernel_map->dso->syms);
|
||||
int kernel_range = 0;
|
||||
|
||||
while (next) {
|
||||
char *module;
|
||||
|
||||
pos = rb_entry(next, struct symbol, rb_node);
|
||||
next = rb_next(&pos->rb_node);
|
||||
|
||||
module = strchr(pos->name, '\t');
|
||||
if (module) {
|
||||
if (!use_modules)
|
||||
continue;
|
||||
*module = '\0';
|
||||
module = strchr(module + 1, '[');
|
||||
if (!module)
|
||||
continue;
|
||||
module_name_end = strchr(module + 1, ']');
|
||||
if (!module_name_end)
|
||||
continue;
|
||||
*(module_name_end + 1) = '\0';
|
||||
goto delete_symbol;
|
||||
|
||||
*module++ = '\0';
|
||||
|
||||
if (strcmp(map->dso->name, module)) {
|
||||
map = kernel_maps__find_by_dso_name(module);
|
||||
if (!map) {
|
||||
|
|
@ -263,50 +313,77 @@ static int maps__load_kallsyms(symbol_filter_t filter, int use_modules, int v)
|
|||
return -1;
|
||||
}
|
||||
}
|
||||
start = map->map_ip(map, start);
|
||||
} else
|
||||
map = kernel_map;
|
||||
/*
|
||||
* Well fix up the end later, when we have all sorted.
|
||||
* So that we look just like we get from .ko files,
|
||||
* i.e. not prelinked, relative to map->start.
|
||||
*/
|
||||
sym = symbol__new(start, 0, symbol_name,
|
||||
map->dso->sym_priv_size, v);
|
||||
pos->start = map->map_ip(map, pos->start);
|
||||
pos->end = map->map_ip(map, pos->end);
|
||||
} else if (map != kernel_map) {
|
||||
char dso_name[PATH_MAX];
|
||||
struct dso *dso;
|
||||
|
||||
if (sym == NULL)
|
||||
goto out_delete_line;
|
||||
snprintf(dso_name, sizeof(dso_name), "[kernel].%d",
|
||||
kernel_range++);
|
||||
|
||||
if (filter && filter(map, sym))
|
||||
symbol__delete(sym, map->dso->sym_priv_size);
|
||||
else {
|
||||
dso__insert_symbol(map->dso, sym);
|
||||
dso = dso__new(dso_name,
|
||||
kernel_map->dso->sym_priv_size);
|
||||
if (dso == NULL)
|
||||
return -1;
|
||||
|
||||
map = map__new2(pos->start, dso);
|
||||
if (map == NULL) {
|
||||
dso__delete(dso);
|
||||
return -1;
|
||||
}
|
||||
|
||||
map->map_ip = vdso__map_ip;
|
||||
kernel_maps__insert(map);
|
||||
++kernel_range;
|
||||
}
|
||||
|
||||
if (filter && filter(map, pos)) {
|
||||
delete_symbol:
|
||||
rb_erase(&pos->rb_node, &kernel_map->dso->syms);
|
||||
symbol__delete(pos, kernel_map->dso->sym_priv_size);
|
||||
} else {
|
||||
if (map != kernel_map) {
|
||||
rb_erase(&pos->rb_node, &kernel_map->dso->syms);
|
||||
dso__insert_symbol(map->dso, pos);
|
||||
}
|
||||
count++;
|
||||
}
|
||||
}
|
||||
|
||||
free(line);
|
||||
fclose(file);
|
||||
|
||||
return count;
|
||||
|
||||
out_delete_line:
|
||||
free(line);
|
||||
out_failure:
|
||||
return -1;
|
||||
}
|
||||
|
||||
static size_t kernel_maps__fprintf(FILE *fp)
|
||||
|
||||
static int kernel_maps__load_kallsyms(symbol_filter_t filter,
|
||||
int use_modules, int v)
|
||||
{
|
||||
if (kernel_maps__load_all_kallsyms(v))
|
||||
return -1;
|
||||
|
||||
dso__fixup_sym_end(kernel_map->dso);
|
||||
|
||||
return kernel_maps__split_kallsyms(filter, use_modules);
|
||||
}
|
||||
|
||||
static size_t kernel_maps__fprintf(FILE *fp, int v)
|
||||
{
|
||||
size_t printed = fprintf(stderr, "Kernel maps:\n");
|
||||
struct rb_node *nd;
|
||||
|
||||
printed += map__fprintf(kernel_map, fp);
|
||||
printed += dso__fprintf(kernel_map->dso, fp);
|
||||
|
||||
for (nd = rb_first(&kernel_maps); 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 (v > 1) {
|
||||
printed += dso__fprintf(pos->dso, fp);
|
||||
printed += fprintf(fp, "--\n");
|
||||
}
|
||||
}
|
||||
|
||||
return printed + fprintf(stderr, "END kernel maps\n");
|
||||
|
|
@ -594,6 +671,9 @@ static int dso__load_sym(struct dso *self, struct map *map, const char *name,
|
|||
int fd, symbol_filter_t filter, int kernel,
|
||||
int kmodule, int v)
|
||||
{
|
||||
struct map *curr_map = map;
|
||||
struct dso *curr_dso = self;
|
||||
size_t dso_name_len = strlen(self->short_name);
|
||||
Elf_Data *symstrs, *secstrs;
|
||||
uint32_t nr_syms;
|
||||
int err = -1;
|
||||
|
|
@ -660,10 +740,9 @@ static int dso__load_sym(struct dso *self, struct map *map, const char *name,
|
|||
elf_symtab__for_each_symbol(syms, nr_syms, idx, sym) {
|
||||
struct symbol *f;
|
||||
const char *elf_name;
|
||||
char *demangled;
|
||||
char *demangled = NULL;
|
||||
int is_label = elf_sym__is_label(&sym);
|
||||
const char *section_name;
|
||||
u64 sh_offset = 0;
|
||||
|
||||
if (!is_label && !elf_sym__is_function(&sym))
|
||||
continue;
|
||||
|
|
@ -677,14 +756,51 @@ static int dso__load_sym(struct dso *self, struct map *map, const char *name,
|
|||
if (is_label && !elf_sec__is_text(&shdr, secstrs))
|
||||
continue;
|
||||
|
||||
elf_name = elf_sym__name(&sym, symstrs);
|
||||
section_name = elf_sec__name(&shdr, secstrs);
|
||||
|
||||
if ((kernel || kmodule)) {
|
||||
if (strstr(section_name, ".init"))
|
||||
sh_offset = shdr.sh_offset;
|
||||
if (kernel || kmodule) {
|
||||
char dso_name[PATH_MAX];
|
||||
|
||||
if (strcmp(section_name,
|
||||
curr_dso->short_name + dso_name_len) == 0)
|
||||
goto new_symbol;
|
||||
|
||||
if (strcmp(section_name, ".text") == 0) {
|
||||
curr_map = map;
|
||||
curr_dso = self;
|
||||
goto new_symbol;
|
||||
}
|
||||
|
||||
if (self->adjust_symbols) {
|
||||
snprintf(dso_name, sizeof(dso_name),
|
||||
"%s%s", self->short_name, section_name);
|
||||
|
||||
curr_map = kernel_maps__find_by_dso_name(dso_name);
|
||||
if (curr_map == NULL) {
|
||||
u64 start = sym.st_value;
|
||||
|
||||
if (kmodule)
|
||||
start += map->start + shdr.sh_offset;
|
||||
|
||||
curr_dso = dso__new(dso_name, self->sym_priv_size);
|
||||
if (curr_dso == NULL)
|
||||
goto out_elf_end;
|
||||
curr_map = map__new2(start, curr_dso);
|
||||
if (curr_map == NULL) {
|
||||
dso__delete(curr_dso);
|
||||
goto out_elf_end;
|
||||
}
|
||||
curr_map->map_ip = vdso__map_ip;
|
||||
curr_dso->origin = DSO__ORIG_KERNEL;
|
||||
kernel_maps__insert(curr_map);
|
||||
dsos__add(curr_dso);
|
||||
} else
|
||||
curr_dso = curr_map->dso;
|
||||
|
||||
goto new_symbol;
|
||||
}
|
||||
|
||||
if (curr_dso->adjust_symbols) {
|
||||
if (v > 2)
|
||||
printf("adjusting symbol: st_value: %Lx sh_addr: %Lx sh_offset: %Lx\n",
|
||||
(u64)sym.st_value, (u64)shdr.sh_addr, (u64)shdr.sh_offset);
|
||||
|
|
@ -696,25 +812,29 @@ static int dso__load_sym(struct dso *self, struct map *map, const char *name,
|
|||
* DWARF DW_compile_unit has this, but we don't always have access
|
||||
* to it...
|
||||
*/
|
||||
elf_name = elf_sym__name(&sym, symstrs);
|
||||
demangled = bfd_demangle(NULL, elf_name, DMGL_PARAMS | DMGL_ANSI);
|
||||
if (demangled != NULL)
|
||||
elf_name = demangled;
|
||||
|
||||
f = symbol__new(sym.st_value + sh_offset, sym.st_size, elf_name,
|
||||
self->sym_priv_size, v);
|
||||
new_symbol:
|
||||
f = symbol__new(sym.st_value, sym.st_size, elf_name,
|
||||
curr_dso->sym_priv_size, v);
|
||||
free(demangled);
|
||||
if (!f)
|
||||
goto out_elf_end;
|
||||
|
||||
if (filter && filter(map, f))
|
||||
symbol__delete(f, self->sym_priv_size);
|
||||
if (filter && filter(curr_map, f))
|
||||
symbol__delete(f, curr_dso->sym_priv_size);
|
||||
else {
|
||||
dso__insert_symbol(self, f);
|
||||
dso__insert_symbol(curr_dso, f);
|
||||
nr++;
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* For misannotated, zeroed, ASM function sizes.
|
||||
*/
|
||||
if (nr > 0)
|
||||
dso__fixup_sym_end(self);
|
||||
err = nr;
|
||||
out_elf_end:
|
||||
elf_end(elf);
|
||||
|
|
@ -883,27 +1003,17 @@ static void kernel_maps__insert(struct map *map)
|
|||
|
||||
struct symbol *kernel_maps__find_symbol(u64 ip, struct map **mapp)
|
||||
{
|
||||
/*
|
||||
* We can't have kernel_map in kernel_maps because it spans an address
|
||||
* space that includes the modules. The right way to fix this is to
|
||||
* create several maps, so that we don't have overlapping ranges with
|
||||
* modules. For now lets look first on the kernel dso.
|
||||
*/
|
||||
struct map *map = maps__find(&kernel_maps, ip);
|
||||
struct symbol *sym;
|
||||
|
||||
if (map) {
|
||||
ip = map->map_ip(map, ip);
|
||||
sym = map->dso->find_symbol(map->dso, ip);
|
||||
} else {
|
||||
map = kernel_map;
|
||||
sym = map->dso->find_symbol(map->dso, ip);
|
||||
}
|
||||
|
||||
if (mapp)
|
||||
*mapp = map;
|
||||
|
||||
return sym;
|
||||
if (map) {
|
||||
ip = map->map_ip(map, ip);
|
||||
return map->dso->find_symbol(map->dso, ip);
|
||||
}
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
struct map *kernel_maps__find_by_dso_name(const char *name)
|
||||
|
|
@ -994,6 +1104,14 @@ static int dsos__load_modules_sym_dir(char *dirname,
|
|||
last = rb_last(&map->dso->syms);
|
||||
if (last) {
|
||||
struct symbol *sym;
|
||||
/*
|
||||
* We do this here as well, even having the
|
||||
* symbol size found in the symtab because
|
||||
* misannotated ASM symbols may have the size
|
||||
* set to zero.
|
||||
*/
|
||||
dso__fixup_sym_end(map->dso);
|
||||
|
||||
sym = rb_entry(last, struct symbol, rb_node);
|
||||
map->end = map->start + sym->end;
|
||||
}
|
||||
|
|
@ -1163,17 +1281,11 @@ int dsos__load_kernel(const char *vmlinux, unsigned int sym_priv_size,
|
|||
}
|
||||
|
||||
if (err <= 0)
|
||||
err = maps__load_kallsyms(filter, use_modules, v);
|
||||
err = kernel_maps__load_kallsyms(filter, use_modules, v);
|
||||
|
||||
if (err > 0) {
|
||||
struct rb_node *node = rb_first(&dso->syms);
|
||||
struct symbol *sym = rb_entry(node, struct symbol, rb_node);
|
||||
/*
|
||||
* Now that we have all sorted out, just set the ->end of all
|
||||
* symbols that still don't have it.
|
||||
*/
|
||||
dso__set_symbols_end(dso);
|
||||
kernel_maps__fixup_sym_end();
|
||||
|
||||
kernel_map->start = sym->start;
|
||||
node = rb_last(&dso->syms);
|
||||
|
|
@ -1181,14 +1293,16 @@ int dsos__load_kernel(const char *vmlinux, unsigned int sym_priv_size,
|
|||
kernel_map->end = sym->end;
|
||||
|
||||
dso->origin = DSO__ORIG_KERNEL;
|
||||
kernel_maps__insert(kernel_map);
|
||||
/*
|
||||
* XXX See kernel_maps__find_symbol comment
|
||||
* kernel_maps__insert(kernel_map)
|
||||
* Now that we have all sorted out, just set the ->end of all
|
||||
* maps:
|
||||
*/
|
||||
kernel_maps__fixup_end();
|
||||
dsos__add(dso);
|
||||
|
||||
if (v > 0)
|
||||
kernel_maps__fprintf(stderr);
|
||||
kernel_maps__fprintf(stderr, v);
|
||||
}
|
||||
|
||||
return err;
|
||||
|
|
|
|||
Loading…
Reference in a new issue