korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-15 00:04:15 +08:00
Code Issues Packages Projects Releases Wiki Activity
bd23ac11fe
linux/tools/perf/util/symbol.c
Arnaldo Carvalho de Melo fb71c86cc8 perf tools: Remove util.h from where it is not needed 
Check that it is not needed and remove, fixing up some fallout for
places where it was only serving to get something else.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-9h6dg6lsqe2usyqjh5rrues4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-09-20 09:19:20 -03:00

2396 lines
53 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0
#include <dirent.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <linux/capability.h>
#include <linux/kernel.h>
#include <linux/mman.h>
#include <linux/string.h>
#include <linux/time64.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <fcntl.h>
#include <unistd.h>
#include <inttypes.h>
#include "annotate.h"
#include "build-id.h"
#include "cap.h"
#include "dso.h"
#include "util.h" // lsdir()
#include "debug.h"
#include "event.h"
#include "machine.h"
#include "map.h"
#include "symbol.h"
#include "map_symbol.h"
#include "mem-events.h"
#include "symsrc.h"
#include "strlist.h"
#include "intlist.h"
#include "namespaces.h"
#include "header.h"
#include "path.h"
#include <linux/ctype.h>
#include <linux/zalloc.h>
#include <elf.h>
#include <limits.h>
#include <symbol/kallsyms.h>
#include <sys/utsname.h>
static int dso__load_kernel_sym(struct dso *dso, struct map *map);
static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map);
static bool symbol__is_idle(const char *name);
int vmlinux_path__nr_entries;
char **vmlinux_path;
struct symbol_conf symbol_conf = {
.nanosecs = false,
.use_modules = true,
.try_vmlinux_path = true,
.demangle = true,
.demangle_kernel = false,
.cumulate_callchain = true,
.time_quantum = 100 * NSEC_PER_MSEC, /* 100ms */
.show_hist_headers = true,
.symfs = "",
.event_group = true,
.inline_name = true,
.res_sample = 0,
};
static enum dso_binary_type binary_type_symtab[] = {
DSO_BINARY_TYPE__KALLSYMS,
DSO_BINARY_TYPE__GUEST_KALLSYMS,
DSO_BINARY_TYPE__JAVA_JIT,
DSO_BINARY_TYPE__DEBUGLINK,
DSO_BINARY_TYPE__BUILD_ID_CACHE,
DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO,
DSO_BINARY_TYPE__FEDORA_DEBUGINFO,
DSO_BINARY_TYPE__UBUNTU_DEBUGINFO,
DSO_BINARY_TYPE__BUILDID_DEBUGINFO,
DSO_BINARY_TYPE__SYSTEM_PATH_DSO,
DSO_BINARY_TYPE__GUEST_KMODULE,
DSO_BINARY_TYPE__GUEST_KMODULE_COMP,
DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE,
DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP,
DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO,
DSO_BINARY_TYPE__NOT_FOUND,
};
#define DSO_BINARY_TYPE__SYMTAB_CNT ARRAY_SIZE(binary_type_symtab)
static bool symbol_type__filter(char symbol_type)
{
symbol_type = toupper(symbol_type);
return symbol_type == 'T' || symbol_type == 'W' || symbol_type == 'D' || symbol_type == 'B';
}
static int prefix_underscores_count(const char *str)
{
const char *tail = str;
while (*tail == '_')
tail++;
return tail - str;
}
void __weak arch__symbols__fixup_end(struct symbol *p, struct symbol *c)
{
p->end = c->start;
}
const char * __weak arch__normalize_symbol_name(const char *name)
{
return name;
}
int __weak arch__compare_symbol_names(const char *namea, const char *nameb)
{
return strcmp(namea, nameb);
}
int __weak arch__compare_symbol_names_n(const char *namea, const char *nameb,
unsigned int n)
{
return strncmp(namea, nameb, n);
}
int __weak arch__choose_best_symbol(struct symbol *syma,
struct symbol *symb __maybe_unused)
{
/* Avoid "SyS" kernel syscall aliases */
if (strlen(syma->name) >= 3 && !strncmp(syma->name, "SyS", 3))
return SYMBOL_B;
if (strlen(syma->name) >= 10 && !strncmp(syma->name, "compat_SyS", 10))
return SYMBOL_B;
return SYMBOL_A;
}
static int choose_best_symbol(struct symbol *syma, struct symbol *symb)
{
s64 a;
s64 b;
size_t na, nb;
/* Prefer a symbol with non zero length */
a = syma->end - syma->start;
b = symb->end - symb->start;
if ((b == 0) && (a > 0))
return SYMBOL_A;
else if ((a == 0) && (b > 0))
return SYMBOL_B;
/* Prefer a non weak symbol over a weak one */
a = syma->binding == STB_WEAK;
b = symb->binding == STB_WEAK;
if (b && !a)
return SYMBOL_A;
if (a && !b)
return SYMBOL_B;
/* Prefer a global symbol over a non global one */
a = syma->binding == STB_GLOBAL;
b = symb->binding == STB_GLOBAL;
if (a && !b)
return SYMBOL_A;
if (b && !a)
return SYMBOL_B;
/* Prefer a symbol with less underscores */
a = prefix_underscores_count(syma->name);
b = prefix_underscores_count(symb->name);
if (b > a)
return SYMBOL_A;
else if (a > b)
return SYMBOL_B;
/* Choose the symbol with the longest name */
na = strlen(syma->name);
nb = strlen(symb->name);
if (na > nb)
return SYMBOL_A;
else if (na < nb)
return SYMBOL_B;
return arch__choose_best_symbol(syma, symb);
}
void symbols__fixup_duplicate(struct rb_root_cached *symbols)
{
struct rb_node *nd;
struct symbol *curr, *next;
if (symbol_conf.allow_aliases)
return;
nd = rb_first_cached(symbols);
while (nd) {
curr = rb_entry(nd, struct symbol, rb_node);
again:
nd = rb_next(&curr->rb_node);
next = rb_entry(nd, struct symbol, rb_node);
if (!nd)
break;
if (curr->start != next->start)
continue;
if (choose_best_symbol(curr, next) == SYMBOL_A) {
rb_erase_cached(&next->rb_node, symbols);
symbol__delete(next);
goto again;
} else {
nd = rb_next(&curr->rb_node);
rb_erase_cached(&curr->rb_node, symbols);
symbol__delete(curr);
}
}
}
void symbols__fixup_end(struct rb_root_cached *symbols)
{
struct rb_node *nd, *prevnd = rb_first_cached(symbols);
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)) {
prev = curr;
curr = rb_entry(nd, struct symbol, rb_node);
if (prev->end == prev->start && prev->end != curr->start)
arch__symbols__fixup_end(prev, curr);
}
/* Last entry */
if (curr->end == curr->start)
curr->end = roundup(curr->start, 4096) + 4096;
}
void map_groups__fixup_end(struct map_groups *mg)
{
struct maps *maps = &mg->maps;
struct map *next, *curr;
down_write(&maps->lock);
curr = maps__first(maps);
if (curr == NULL)
goto out_unlock;
for (next = map__next(curr); next; next = map__next(curr)) {
if (!curr->end)
curr->end = next->start;
curr = next;
}
/*
* We still haven't the actual symbols, so guess the
* last map final address.
*/
if (!curr->end)
curr->end = ~0ULL;
out_unlock:
up_write(&maps->lock);
}
struct symbol *symbol__new(u64 start, u64 len, u8 binding, u8 type, const char *name)
{
size_t namelen = strlen(name) + 1;
struct symbol *sym = calloc(1, (symbol_conf.priv_size +
sizeof(*sym) + namelen));
if (sym == NULL)
return NULL;
if (symbol_conf.priv_size) {
if (symbol_conf.init_annotation) {
struct annotation *notes = (void *)sym;
pthread_mutex_init(&notes->lock, NULL);
}
sym = ((void *)sym) + symbol_conf.priv_size;
}
sym->start = start;
sym->end = len ? start + len : start;
sym->type = type;
sym->binding = binding;
sym->namelen = namelen - 1;
pr_debug4("%s: %s %#" PRIx64 "-%#" PRIx64 "\n",
__func__, name, start, sym->end);
memcpy(sym->name, name, namelen);
return sym;
}
void symbol__delete(struct symbol *sym)
{
free(((void *)sym) - symbol_conf.priv_size);
}
void symbols__delete(struct rb_root_cached *symbols)
{
struct symbol *pos;
struct rb_node *next = rb_first_cached(symbols);
while (next) {
pos = rb_entry(next, struct symbol, rb_node);
next = rb_next(&pos->rb_node);
rb_erase_cached(&pos->rb_node, symbols);
symbol__delete(pos);
}
}
void __symbols__insert(struct rb_root_cached *symbols,
struct symbol *sym, bool kernel)
{
struct rb_node **p = &symbols->rb_root.rb_node;
struct rb_node *parent = NULL;
const u64 ip = sym->start;
struct symbol *s;
bool leftmost = true;
if (kernel) {
const char *name = sym->name;
/*
* ppc64 uses function descriptors and appends a '.' to the
* start of every instruction address. Remove it.
*/
if (name[0] == '.')
name++;
sym->idle = symbol__is_idle(name);
}
while (*p != NULL) {
parent = *p;
s = rb_entry(parent, struct symbol, rb_node);
if (ip < s->start)
p = &(*p)->rb_left;
else {
p = &(*p)->rb_right;
leftmost = false;
}
}
rb_link_node(&sym->rb_node, parent, p);
rb_insert_color_cached(&sym->rb_node, symbols, leftmost);
}
void symbols__insert(struct rb_root_cached *symbols, struct symbol *sym)
{
__symbols__insert(symbols, sym, false);
}
static struct symbol *symbols__find(struct rb_root_cached *symbols, u64 ip)
{
struct rb_node *n;
if (symbols == NULL)
return NULL;
n = symbols->rb_root.rb_node;
while (n) {
struct symbol *s = rb_entry(n, struct symbol, rb_node);
if (ip < s->start)
n = n->rb_left;
else if (ip > s->end || (ip == s->end && ip != s->start))
n = n->rb_right;
else
return s;
}
return NULL;
}
static struct symbol *symbols__first(struct rb_root_cached *symbols)
{
struct rb_node *n = rb_first_cached(symbols);
if (n)
return rb_entry(n, struct symbol, rb_node);
return NULL;
}
static struct symbol *symbols__last(struct rb_root_cached *symbols)
{
struct rb_node *n = rb_last(&symbols->rb_root);
if (n)
return rb_entry(n, struct symbol, rb_node);
return NULL;
}
static struct symbol *symbols__next(struct symbol *sym)
{
struct rb_node *n = rb_next(&sym->rb_node);
if (n)
return rb_entry(n, struct symbol, rb_node);
return NULL;
}
static void symbols__insert_by_name(struct rb_root_cached *symbols, struct symbol *sym)
{
struct rb_node **p = &symbols->rb_root.rb_node;
struct rb_node *parent = NULL;
struct symbol_name_rb_node *symn, *s;
bool leftmost = true;
symn = container_of(sym, struct symbol_name_rb_node, sym);
while (*p != NULL) {
parent = *p;
s = rb_entry(parent, struct symbol_name_rb_node, rb_node);
if (strcmp(sym->name, s->sym.name) < 0)
p = &(*p)->rb_left;
else {
p = &(*p)->rb_right;
leftmost = false;
}
}
rb_link_node(&symn->rb_node, parent, p);
rb_insert_color_cached(&symn->rb_node, symbols, leftmost);
}
static void symbols__sort_by_name(struct rb_root_cached *symbols,
struct rb_root_cached *source)
{
struct rb_node *nd;
for (nd = rb_first_cached(source); nd; nd = rb_next(nd)) {
struct symbol *pos = rb_entry(nd, struct symbol, rb_node);
symbols__insert_by_name(symbols, pos);
}
}
int symbol__match_symbol_name(const char *name, const char *str,
enum symbol_tag_include includes)
{
const char *versioning;
if (includes == SYMBOL_TAG_INCLUDE__DEFAULT_ONLY &&
(versioning = strstr(name, "@@"))) {
int len = strlen(str);
if (len < versioning - name)
len = versioning - name;
return arch__compare_symbol_names_n(name, str, len);
} else
return arch__compare_symbol_names(name, str);
}
static struct symbol *symbols__find_by_name(struct rb_root_cached *symbols,
const char *name,
enum symbol_tag_include includes)
{
struct rb_node *n;
struct symbol_name_rb_node *s = NULL;
if (symbols == NULL)
return NULL;
n = symbols->rb_root.rb_node;
while (n) {
int cmp;
s = rb_entry(n, struct symbol_name_rb_node, rb_node);
cmp = symbol__match_symbol_name(s->sym.name, name, includes);
if (cmp > 0)
n = n->rb_left;
else if (cmp < 0)
n = n->rb_right;
else
break;
}
if (n == NULL)
return NULL;
if (includes != SYMBOL_TAG_INCLUDE__DEFAULT_ONLY)
/* return first symbol that has same name (if any) */
for (n = rb_prev(n); n; n = rb_prev(n)) {
struct symbol_name_rb_node *tmp;
tmp = rb_entry(n, struct symbol_name_rb_node, rb_node);
if (arch__compare_symbol_names(tmp->sym.name, s->sym.name))
break;
s = tmp;
}
return &s->sym;
}
void dso__reset_find_symbol_cache(struct dso *dso)
{
dso->last_find_result.addr = 0;
dso->last_find_result.symbol = NULL;
}
void dso__insert_symbol(struct dso *dso, struct symbol *sym)
{
__symbols__insert(&dso->symbols, sym, dso->kernel);
/* update the symbol cache if necessary */
if (dso->last_find_result.addr >= sym->start &&
(dso->last_find_result.addr < sym->end ||
sym->start == sym->end)) {
dso->last_find_result.symbol = sym;
}
}
struct symbol *dso__find_symbol(struct dso *dso, u64 addr)
{
if (dso->last_find_result.addr != addr || dso->last_find_result.symbol == NULL) {
dso->last_find_result.addr = addr;
dso->last_find_result.symbol = symbols__find(&dso->symbols, addr);
}
return dso->last_find_result.symbol;
}
struct symbol *dso__first_symbol(struct dso *dso)
{
return symbols__first(&dso->symbols);
}
struct symbol *dso__last_symbol(struct dso *dso)
{
return symbols__last(&dso->symbols);
}
struct symbol *dso__next_symbol(struct symbol *sym)
{
return symbols__next(sym);
}
struct symbol *symbol__next_by_name(struct symbol *sym)
{
struct symbol_name_rb_node *s = container_of(sym, struct symbol_name_rb_node, sym);
struct rb_node *n = rb_next(&s->rb_node);
return n ? &rb_entry(n, struct symbol_name_rb_node, rb_node)->sym : NULL;
}
/*
* Returns first symbol that matched with @name.
*/
struct symbol *dso__find_symbol_by_name(struct dso *dso, const char *name)
{
struct symbol *s = symbols__find_by_name(&dso->symbol_names, name,
SYMBOL_TAG_INCLUDE__NONE);
if (!s)
s = symbols__find_by_name(&dso->symbol_names, name,
SYMBOL_TAG_INCLUDE__DEFAULT_ONLY);
return s;
}
void dso__sort_by_name(struct dso *dso)
{
dso__set_sorted_by_name(dso);
return symbols__sort_by_name(&dso->symbol_names, &dso->symbols);
}
int modules__parse(const char *filename, void *arg,
int (*process_module)(void *arg, const char *name,
u64 start, u64 size))
{
char *line = NULL;
size_t n;
FILE *file;
int err = 0;
file = fopen(filename, "r");
if (file == NULL)
return -1;
while (1) {
char name[PATH_MAX];
u64 start, size;
char *sep, *endptr;
ssize_t line_len;
line_len = getline(&line, &n, file);
if (line_len < 0) {
if (feof(file))
break;
err = -1;
goto out;
}
if (!line) {
err = -1;
goto out;
}
line[--line_len] = '\0'; /* \n */
sep = strrchr(line, 'x');
if (sep == NULL)
continue;
hex2u64(sep + 1, &start);
sep = strchr(line, ' ');
if (sep == NULL)
continue;
*sep = '\0';
scnprintf(name, sizeof(name), "[%s]", line);
size = strtoul(sep + 1, &endptr, 0);
if (*endptr != ' ' && *endptr != '\t')
continue;
err = process_module(arg, name, start, size);
if (err)
break;
}
out:
free(line);
fclose(file);
return err;
}
/*
* These are symbols in the kernel image, so make sure that
* sym is from a kernel DSO.
*/
static bool symbol__is_idle(const char *name)
{
const char * const idle_symbols[] = {
"arch_cpu_idle",
"cpu_idle",
"cpu_startup_entry",
"intel_idle",
"default_idle",
"native_safe_halt",
"enter_idle",
"exit_idle",
"mwait_idle",
"mwait_idle_with_hints",
"poll_idle",
"ppc64_runlatch_off",
"pseries_dedicated_idle_sleep",
NULL
};
int i;
for (i = 0; idle_symbols[i]; i++) {
if (!strcmp(idle_symbols[i], name))
return true;
}
return false;
}
static int map__process_kallsym_symbol(void *arg, const char *name,
char type, u64 start)
{
struct symbol *sym;
struct dso *dso = arg;
struct rb_root_cached *root = &dso->symbols;
if (!symbol_type__filter(type))
return 0;
/*
* module symbols are not sorted so we add all
* symbols, setting length to 0, and rely on
* symbols__fixup_end() to fix it up.
*/
sym = symbol__new(start, 0, kallsyms2elf_binding(type), kallsyms2elf_type(type), name);
if (sym == NULL)
return -ENOMEM;
/*
* We will pass the symbols to the filter later, in
* map__split_kallsyms, when we have split the maps per module
*/
__symbols__insert(root, sym, !strchr(name, '['));
return 0;
}
/*
* 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 dso__load_all_kallsyms(struct dso *dso, const char *filename)
{
return kallsyms__parse(filename, dso, map__process_kallsym_symbol);
}
static int map_groups__split_kallsyms_for_kcore(struct map_groups *kmaps, struct dso *dso)
{
struct map *curr_map;
struct symbol *pos;
int count = 0;
struct rb_root_cached old_root = dso->symbols;
struct rb_root_cached *root = &dso->symbols;
struct rb_node *next = rb_first_cached(root);
if (!kmaps)
return -1;
*root = RB_ROOT_CACHED;
while (next) {
char *module;
pos = rb_entry(next, struct symbol, rb_node);
next = rb_next(&pos->rb_node);
rb_erase_cached(&pos->rb_node, &old_root);
RB_CLEAR_NODE(&pos->rb_node);
module = strchr(pos->name, '\t');
if (module)
*module = '\0';
curr_map = map_groups__find(kmaps, pos->start);
if (!curr_map) {
symbol__delete(pos);
continue;
}
pos->start -= curr_map->start - curr_map->pgoff;
if (pos->end > curr_map->end)
pos->end = curr_map->end;
if (pos->end)
pos->end -= curr_map->start - curr_map->pgoff;
symbols__insert(&curr_map->dso->symbols, pos);
++count;
}
/* Symbols have been adjusted */
dso->adjust_symbols = 1;
return count;
}
/*
* 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 map_groups__split_kallsyms(struct map_groups *kmaps, struct dso *dso, u64 delta,
struct map *initial_map)
{
struct machine *machine;
struct map *curr_map = initial_map;
struct symbol *pos;
int count = 0, moved = 0;
struct rb_root_cached *root = &dso->symbols;
struct rb_node *next = rb_first_cached(root);
int kernel_range = 0;
bool x86_64;
if (!kmaps)
return -1;
machine = kmaps->machine;
x86_64 = machine__is(machine, "x86_64");
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 (!symbol_conf.use_modules)
goto discard_symbol;
*module++ = '\0';
if (strcmp(curr_map->dso->short_name, module)) {
if (curr_map != initial_map &&
dso->kernel == DSO_TYPE_GUEST_KERNEL &&
machine__is_default_guest(machine)) {
/*
* We assume all symbols of a module are
* continuous in * kallsyms, so curr_map
* points to a module and all its
* symbols are in its kmap. Mark it as
* loaded.
*/
dso__set_loaded(curr_map->dso);
}
curr_map = map_groups__find_by_name(kmaps, module);
if (curr_map == NULL) {
pr_debug("%s/proc/{kallsyms,modules} "
"inconsistency while looking "
"for \"%s\" module!\n",
machine->root_dir, module);
curr_map = initial_map;
goto discard_symbol;
}
if (curr_map->dso->loaded &&
!machine__is_default_guest(machine))
goto discard_symbol;
}
/*
* So that we look just like we get from .ko files,
* i.e. not prelinked, relative to initial_map->start.
*/
pos->start = curr_map->map_ip(curr_map, pos->start);
pos->end = curr_map->map_ip(curr_map, pos->end);
} else if (x86_64 && is_entry_trampoline(pos->name)) {
/*
* These symbols are not needed anymore since the
* trampoline maps refer to the text section and it's
* symbols instead. Avoid having to deal with
* relocations, and the assumption that the first symbol
* is the start of kernel text, by simply removing the
* symbols at this point.
*/
goto discard_symbol;
} else if (curr_map != initial_map) {
char dso_name[PATH_MAX];
struct dso *ndso;
if (delta) {
/* Kernel was relocated at boot time */
pos->start -= delta;
pos->end -= delta;
}
if (count == 0) {
curr_map = initial_map;
goto add_symbol;
}
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
snprintf(dso_name, sizeof(dso_name),
"[guest.kernel].%d",
kernel_range++);
else
snprintf(dso_name, sizeof(dso_name),
"[kernel].%d",
kernel_range++);
ndso = dso__new(dso_name);
if (ndso == NULL)
return -1;
ndso->kernel = dso->kernel;
curr_map = map__new2(pos->start, ndso);
if (curr_map == NULL) {
dso__put(ndso);
return -1;
}
curr_map->map_ip = curr_map->unmap_ip = identity__map_ip;
map_groups__insert(kmaps, curr_map);
++kernel_range;
} else if (delta) {
/* Kernel was relocated at boot time */
pos->start -= delta;
pos->end -= delta;
}
add_symbol:
if (curr_map != initial_map) {
rb_erase_cached(&pos->rb_node, root);
symbols__insert(&curr_map->dso->symbols, pos);
++moved;
} else
++count;
continue;
discard_symbol:
rb_erase_cached(&pos->rb_node, root);
symbol__delete(pos);
}
if (curr_map != initial_map &&
dso->kernel == DSO_TYPE_GUEST_KERNEL &&
machine__is_default_guest(kmaps->machine)) {
dso__set_loaded(curr_map->dso);
}
return count + moved;
}
bool symbol__restricted_filename(const char *filename,
const char *restricted_filename)
{
bool restricted = false;
if (symbol_conf.kptr_restrict) {
char *r = realpath(filename, NULL);
if (r != NULL) {
restricted = strcmp(r, restricted_filename) == 0;
free(r);
return restricted;
}
}
return restricted;
}
struct module_info {
struct rb_node rb_node;
char *name;
u64 start;
};
static void add_module(struct module_info *mi, struct rb_root *modules)
{
struct rb_node **p = &modules->rb_node;
struct rb_node *parent = NULL;
struct module_info *m;
while (*p != NULL) {
parent = *p;
m = rb_entry(parent, struct module_info, rb_node);
if (strcmp(mi->name, m->name) < 0)
p = &(*p)->rb_left;
else
p = &(*p)->rb_right;
}
rb_link_node(&mi->rb_node, parent, p);
rb_insert_color(&mi->rb_node, modules);
}
static void delete_modules(struct rb_root *modules)
{
struct module_info *mi;
struct rb_node *next = rb_first(modules);
while (next) {
mi = rb_entry(next, struct module_info, rb_node);
next = rb_next(&mi->rb_node);
rb_erase(&mi->rb_node, modules);
zfree(&mi->name);
free(mi);
}
}
static struct module_info *find_module(const char *name,
struct rb_root *modules)
{
struct rb_node *n = modules->rb_node;
while (n) {
struct module_info *m;
int cmp;
m = rb_entry(n, struct module_info, rb_node);
cmp = strcmp(name, m->name);
if (cmp < 0)
n = n->rb_left;
else if (cmp > 0)
n = n->rb_right;
else
return m;
}
return NULL;
}
static int __read_proc_modules(void *arg, const char *name, u64 start,
u64 size __maybe_unused)
{
struct rb_root *modules = arg;
struct module_info *mi;
mi = zalloc(sizeof(struct module_info));
if (!mi)
return -ENOMEM;
mi->name = strdup(name);
mi->start = start;
if (!mi->name) {
free(mi);
return -ENOMEM;
}
add_module(mi, modules);
return 0;
}
static int read_proc_modules(const char *filename, struct rb_root *modules)
{
if (symbol__restricted_filename(filename, "/proc/modules"))
return -1;
if (modules__parse(filename, modules, __read_proc_modules)) {
delete_modules(modules);
return -1;
}
return 0;
}
int compare_proc_modules(const char *from, const char *to)
{
struct rb_root from_modules = RB_ROOT;
struct rb_root to_modules = RB_ROOT;
struct rb_node *from_node, *to_node;
struct module_info *from_m, *to_m;
int ret = -1;
if (read_proc_modules(from, &from_modules))
return -1;
if (read_proc_modules(to, &to_modules))
goto out_delete_from;
from_node = rb_first(&from_modules);
to_node = rb_first(&to_modules);
while (from_node) {
if (!to_node)
break;
from_m = rb_entry(from_node, struct module_info, rb_node);
to_m = rb_entry(to_node, struct module_info, rb_node);
if (from_m->start != to_m->start ||
strcmp(from_m->name, to_m->name))
break;
from_node = rb_next(from_node);
to_node = rb_next(to_node);
}
if (!from_node && !to_node)
ret = 0;
delete_modules(&to_modules);
out_delete_from:
delete_modules(&from_modules);
return ret;
}
struct map *map_groups__first(struct map_groups *mg)
{
return maps__first(&mg->maps);
}
static int do_validate_kcore_modules(const char *filename,
struct map_groups *kmaps)
{
struct rb_root modules = RB_ROOT;
struct map *old_map;
int err;
err = read_proc_modules(filename, &modules);
if (err)
return err;
old_map = map_groups__first(kmaps);
while (old_map) {
struct map *next = map_groups__next(old_map);
struct module_info *mi;
if (!__map__is_kmodule(old_map)) {
old_map = next;
continue;
}
/* Module must be in memory at the same address */
mi = find_module(old_map->dso->short_name, &modules);
if (!mi || mi->start != old_map->start) {
err = -EINVAL;
goto out;
}
old_map = next;
}
out:
delete_modules(&modules);
return err;
}
/*
* If kallsyms is referenced by name then we look for filename in the same
* directory.
*/
static bool filename_from_kallsyms_filename(char *filename,
const char *base_name,
const char *kallsyms_filename)
{
char *name;
strcpy(filename, kallsyms_filename);
name = strrchr(filename, '/');
if (!name)
return false;
name += 1;
if (!strcmp(name, "kallsyms")) {
strcpy(name, base_name);
return true;
}
return false;
}
static int validate_kcore_modules(const char *kallsyms_filename,
struct map *map)
{
struct map_groups *kmaps = map__kmaps(map);
char modules_filename[PATH_MAX];
if (!kmaps)
return -EINVAL;
if (!filename_from_kallsyms_filename(modules_filename, "modules",
kallsyms_filename))
return -EINVAL;
if (do_validate_kcore_modules(modules_filename, kmaps))
return -EINVAL;
return 0;
}
static int validate_kcore_addresses(const char *kallsyms_filename,
struct map *map)
{
struct kmap *kmap = map__kmap(map);
if (!kmap)
return -EINVAL;
if (kmap->ref_reloc_sym && kmap->ref_reloc_sym->name) {
u64 start;
if (kallsyms__get_function_start(kallsyms_filename,
kmap->ref_reloc_sym->name, &start))
return -ENOENT;
if (start != kmap->ref_reloc_sym->addr)
return -EINVAL;
}
return validate_kcore_modules(kallsyms_filename, map);
}
struct kcore_mapfn_data {
struct dso *dso;
struct list_head maps;
};
static int kcore_mapfn(u64 start, u64 len, u64 pgoff, void *data)
{
struct kcore_mapfn_data *md = data;
struct map *map;
map = map__new2(start, md->dso);
if (map == NULL)
return -ENOMEM;
map->end = map->start + len;
map->pgoff = pgoff;
list_add(&map->node, &md->maps);
return 0;
}
/*
* Merges map into map_groups by splitting the new map
* within the existing map regions.
*/
int map_groups__merge_in(struct map_groups *kmaps, struct map *new_map)
{
struct map *old_map;
LIST_HEAD(merged);
for (old_map = map_groups__first(kmaps); old_map;
old_map = map_groups__next(old_map)) {
/* no overload with this one */
if (new_map->end < old_map->start ||
new_map->start >= old_map->end)
continue;
if (new_map->start < old_map->start) {
/*
* |new......
* |old....
*/
if (new_map->end < old_map->end) {
/*
* |new......| -> |new..|
* |old....| -> |old....|
*/
new_map->end = old_map->start;
} else {
/*
* |new.............| -> |new..| |new..|
* |old....| -> |old....|
*/
struct map *m = map__clone(new_map);
if (!m)
return -ENOMEM;
m->end = old_map->start;
list_add_tail(&m->node, &merged);
new_map->start = old_map->end;
}
} else {
/*
* |new......
* |old....
*/
if (new_map->end < old_map->end) {
/*
* |new..| -> x
* |old.........| -> |old.........|
*/
map__put(new_map);
new_map = NULL;
break;
} else {
/*
* |new......| -> |new...|
* |old....| -> |old....|
*/
new_map->start = old_map->end;
}
}
}
while (!list_empty(&merged)) {
old_map = list_entry(merged.next, struct map, node);
list_del_init(&old_map->node);
map_groups__insert(kmaps, old_map);
map__put(old_map);
}
if (new_map) {
map_groups__insert(kmaps, new_map);
map__put(new_map);
}
return 0;
}
static int dso__load_kcore(struct dso *dso, struct map *map,
const char *kallsyms_filename)
{
struct map_groups *kmaps = map__kmaps(map);
struct kcore_mapfn_data md;
struct map *old_map, *new_map, *replacement_map = NULL;
struct machine *machine;
bool is_64_bit;
int err, fd;
char kcore_filename[PATH_MAX];
u64 stext;
if (!kmaps)
return -EINVAL;
machine = kmaps->machine;
/* This function requires that the map is the kernel map */
if (!__map__is_kernel(map))
return -EINVAL;
if (!filename_from_kallsyms_filename(kcore_filename, "kcore",
kallsyms_filename))
return -EINVAL;
/* Modules and kernel must be present at their original addresses */
if (validate_kcore_addresses(kallsyms_filename, map))
return -EINVAL;
md.dso = dso;
INIT_LIST_HEAD(&md.maps);
fd = open(kcore_filename, O_RDONLY);
if (fd < 0) {
pr_debug("Failed to open %s. Note /proc/kcore requires CAP_SYS_RAWIO capability to access.\n",
kcore_filename);
return -EINVAL;
}
/* Read new maps into temporary lists */
err = file__read_maps(fd, map->prot & PROT_EXEC, kcore_mapfn, &md,
&is_64_bit);
if (err)
goto out_err;
dso->is_64_bit = is_64_bit;
if (list_empty(&md.maps)) {
err = -EINVAL;
goto out_err;
}
/* Remove old maps */
old_map = map_groups__first(kmaps);
while (old_map) {
struct map *next = map_groups__next(old_map);
/*
* We need to preserve eBPF maps even if they are
* covered by kcore, because we need to access
* eBPF dso for source data.
*/
if (old_map != map && !__map__is_bpf_prog(old_map))
map_groups__remove(kmaps, old_map);
old_map = next;
}
machine->trampolines_mapped = false;
/* Find the kernel map using the '_stext' symbol */
if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) {
list_for_each_entry(new_map, &md.maps, node) {
if (stext >= new_map->start && stext < new_map->end) {
replacement_map = new_map;
break;
}
}
}
if (!replacement_map)
replacement_map = list_entry(md.maps.next, struct map, node);
/* Add new maps */
while (!list_empty(&md.maps)) {
new_map = list_entry(md.maps.next, struct map, node);
list_del_init(&new_map->node);
if (new_map == replacement_map) {
map->start = new_map->start;
map->end = new_map->end;
map->pgoff = new_map->pgoff;
map->map_ip = new_map->map_ip;
map->unmap_ip = new_map->unmap_ip;
/* Ensure maps are correctly ordered */
map__get(map);
map_groups__remove(kmaps, map);
map_groups__insert(kmaps, map);
map__put(map);
map__put(new_map);
} else {
/*
* Merge kcore map into existing maps,
* and ensure that current maps (eBPF)
* stay intact.
*/
if (map_groups__merge_in(kmaps, new_map))
goto out_err;
}
}
if (machine__is(machine, "x86_64")) {
u64 addr;
/*
* If one of the corresponding symbols is there, assume the
* entry trampoline maps are too.
*/
if (!kallsyms__get_function_start(kallsyms_filename,
ENTRY_TRAMPOLINE_NAME,
&addr))
machine->trampolines_mapped = true;
}
/*
* Set the data type and long name so that kcore can be read via
* dso__data_read_addr().
*/
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
dso->binary_type = DSO_BINARY_TYPE__GUEST_KCORE;
else
dso->binary_type = DSO_BINARY_TYPE__KCORE;
dso__set_long_name(dso, strdup(kcore_filename), true);
close(fd);
if (map->prot & PROT_EXEC)
pr_debug("Using %s for kernel object code\n", kcore_filename);
else
pr_debug("Using %s for kernel data\n", kcore_filename);
return 0;
out_err:
while (!list_empty(&md.maps)) {
map = list_entry(md.maps.next, struct map, node);
list_del_init(&map->node);
map__put(map);
}
close(fd);
return -EINVAL;
}
/*
* If the kernel is relocated at boot time, kallsyms won't match. Compute the
* delta based on the relocation reference symbol.
*/
static int kallsyms__delta(struct kmap *kmap, const char *filename, u64 *delta)
{
u64 addr;
if (!kmap->ref_reloc_sym || !kmap->ref_reloc_sym->name)
return 0;
if (kallsyms__get_function_start(filename, kmap->ref_reloc_sym->name, &addr))
return -1;
*delta = addr - kmap->ref_reloc_sym->addr;
return 0;
}
int __dso__load_kallsyms(struct dso *dso, const char *filename,
struct map *map, bool no_kcore)
{
struct kmap *kmap = map__kmap(map);
u64 delta = 0;
if (symbol__restricted_filename(filename, "/proc/kallsyms"))
return -1;
if (!kmap || !kmap->kmaps)
return -1;
if (dso__load_all_kallsyms(dso, filename) < 0)
return -1;
if (kallsyms__delta(kmap, filename, &delta))
return -1;
symbols__fixup_end(&dso->symbols);
symbols__fixup_duplicate(&dso->symbols);
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
dso->symtab_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
else
dso->symtab_type = DSO_BINARY_TYPE__KALLSYMS;
if (!no_kcore && !dso__load_kcore(dso, map, filename))
return map_groups__split_kallsyms_for_kcore(kmap->kmaps, dso);
else
return map_groups__split_kallsyms(kmap->kmaps, dso, delta, map);
}
int dso__load_kallsyms(struct dso *dso, const char *filename,
struct map *map)
{
return __dso__load_kallsyms(dso, filename, map, false);
}
static int dso__load_perf_map(const char *map_path, struct dso *dso)
{
char *line = NULL;
size_t n;
FILE *file;
int nr_syms = 0;
file = fopen(map_path, "r");
if (file == NULL)
goto out_failure;
while (!feof(file)) {
u64 start, size;
struct symbol *sym;
int line_len, len;
line_len = getline(&line, &n, file);
if (line_len < 0)
break;
if (!line)
goto out_failure;
line[--line_len] = '\0'; /* \n */
len = hex2u64(line, &start);
len++;
if (len + 2 >= line_len)
continue;
len += hex2u64(line + len, &size);
len++;
if (len + 2 >= line_len)
continue;
sym = symbol__new(start, size, STB_GLOBAL, STT_FUNC, line + len);
if (sym == NULL)
goto out_delete_line;
symbols__insert(&dso->symbols, sym);
nr_syms++;
}
free(line);
fclose(file);
return nr_syms;
out_delete_line:
free(line);
out_failure:
return -1;
}
static bool dso__is_compatible_symtab_type(struct dso *dso, bool kmod,
enum dso_binary_type type)
{
switch (type) {
case DSO_BINARY_TYPE__JAVA_JIT:
case DSO_BINARY_TYPE__DEBUGLINK:
case DSO_BINARY_TYPE__SYSTEM_PATH_DSO:
case DSO_BINARY_TYPE__FEDORA_DEBUGINFO:
case DSO_BINARY_TYPE__UBUNTU_DEBUGINFO:
case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
return !kmod && dso->kernel == DSO_TYPE_USER;
case DSO_BINARY_TYPE__KALLSYMS:
case DSO_BINARY_TYPE__VMLINUX:
case DSO_BINARY_TYPE__KCORE:
return dso->kernel == DSO_TYPE_KERNEL;
case DSO_BINARY_TYPE__GUEST_KALLSYMS:
case DSO_BINARY_TYPE__GUEST_VMLINUX:
case DSO_BINARY_TYPE__GUEST_KCORE:
return dso->kernel == DSO_TYPE_GUEST_KERNEL;
case DSO_BINARY_TYPE__GUEST_KMODULE:
case DSO_BINARY_TYPE__GUEST_KMODULE_COMP:
case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE:
case DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP:
/*
* kernel modules know their symtab type - it's set when
* creating a module dso in machine__findnew_module_map().
*/
return kmod && dso->symtab_type == type;
case DSO_BINARY_TYPE__BUILD_ID_CACHE:
case DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO:
return true;
case DSO_BINARY_TYPE__BPF_PROG_INFO:
case DSO_BINARY_TYPE__NOT_FOUND:
default:
return false;
}
}
/* Checks for the existence of the perf-<pid>.map file in two different
* locations. First, if the process is a separate mount namespace, check in
* that namespace using the pid of the innermost pid namespace. If's not in a
* namespace, or the file can't be found there, try in the mount namespace of
* the tracing process using our view of its pid.
*/
static int dso__find_perf_map(char *filebuf, size_t bufsz,
struct nsinfo **nsip)
{
struct nscookie nsc;
struct nsinfo *nsi;
struct nsinfo *nnsi;
int rc = -1;
nsi = *nsip;
if (nsi->need_setns) {
snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsi->nstgid);
nsinfo__mountns_enter(nsi, &nsc);
rc = access(filebuf, R_OK);
nsinfo__mountns_exit(&nsc);
if (rc == 0)
return rc;
}
nnsi = nsinfo__copy(nsi);
if (nnsi) {
nsinfo__put(nsi);
nnsi->need_setns = false;
snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nnsi->tgid);
*nsip = nnsi;
rc = 0;
}
return rc;
}
int dso__load(struct dso *dso, struct map *map)
{
char *name;
int ret = -1;
u_int i;
struct machine *machine;
char *root_dir = (char *) "";
int ss_pos = 0;
struct symsrc ss_[2];
struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
bool kmod;
bool perfmap;
unsigned char build_id[BUILD_ID_SIZE];
struct nscookie nsc;
char newmapname[PATH_MAX];
const char *map_path = dso->long_name;
perfmap = strncmp(dso->name, "/tmp/perf-", 10) == 0;
if (perfmap) {
if (dso->nsinfo && (dso__find_perf_map(newmapname,
sizeof(newmapname), &dso->nsinfo) == 0)) {
map_path = newmapname;
}
}
nsinfo__mountns_enter(dso->nsinfo, &nsc);
pthread_mutex_lock(&dso->lock);
/* check again under the dso->lock */
if (dso__loaded(dso)) {
ret = 1;
goto out;
}
if (map->groups && map->groups->machine)
machine = map->groups->machine;
else
machine = NULL;
if (dso->kernel) {
if (dso->kernel == DSO_TYPE_KERNEL)
ret = dso__load_kernel_sym(dso, map);
else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
ret = dso__load_guest_kernel_sym(dso, map);
if (machine__is(machine, "x86_64"))
machine__map_x86_64_entry_trampolines(machine, dso);
goto out;
}
dso->adjust_symbols = 0;
if (perfmap) {
ret = dso__load_perf_map(map_path, dso);
dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
DSO_BINARY_TYPE__NOT_FOUND;
goto out;
}
if (machine)
root_dir = machine->root_dir;
name = malloc(PATH_MAX);
if (!name)
goto out;
kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE ||
dso->symtab_type == DSO_BINARY_TYPE__GUEST_KMODULE_COMP;
/*
* Read the build id if possible. This is required for
* DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
*/
if (!dso->has_build_id &&
is_regular_file(dso->long_name)) {
__symbol__join_symfs(name, PATH_MAX, dso->long_name);
if (filename__read_build_id(name, build_id, BUILD_ID_SIZE) > 0)
dso__set_build_id(dso, build_id);
}
/*
* Iterate over candidate debug images.
* Keep track of "interesting" ones (those which have a symtab, dynsym,
* and/or opd section) for processing.
*/
for (i = 0; i < DSO_BINARY_TYPE__SYMTAB_CNT; i++) {
struct symsrc *ss = &ss_[ss_pos];
bool next_slot = false;
bool is_reg;
bool nsexit;
int sirc = -1;
enum dso_binary_type symtab_type = binary_type_symtab[i];
nsexit = (symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE ||
symtab_type == DSO_BINARY_TYPE__BUILD_ID_CACHE_DEBUGINFO);
if (!dso__is_compatible_symtab_type(dso, kmod, symtab_type))
continue;
if (dso__read_binary_type_filename(dso, symtab_type,
root_dir, name, PATH_MAX))
continue;
if (nsexit)
nsinfo__mountns_exit(&nsc);
is_reg = is_regular_file(name);
if (is_reg)
sirc = symsrc__init(ss, dso, name, symtab_type);
if (nsexit)
nsinfo__mountns_enter(dso->nsinfo, &nsc);
if (!is_reg || sirc < 0)
continue;
if (!syms_ss && symsrc__has_symtab(ss)) {
syms_ss = ss;
next_slot = true;
if (!dso->symsrc_filename)
dso->symsrc_filename = strdup(name);
}
if (!runtime_ss && symsrc__possibly_runtime(ss)) {
runtime_ss = ss;
next_slot = true;
}
if (next_slot) {
ss_pos++;
if (syms_ss && runtime_ss)
break;
} else {
symsrc__destroy(ss);
}
}
if (!runtime_ss && !syms_ss)
goto out_free;
if (runtime_ss && !syms_ss) {
syms_ss = runtime_ss;
}
/* We'll have to hope for the best */
if (!runtime_ss && syms_ss)
runtime_ss = syms_ss;
if (syms_ss)
ret = dso__load_sym(dso, map, syms_ss, runtime_ss, kmod);
else
ret = -1;
if (ret > 0) {
int nr_plt;
nr_plt = dso__synthesize_plt_symbols(dso, runtime_ss);
if (nr_plt > 0)
ret += nr_plt;
}
for (; ss_pos > 0; ss_pos--)
symsrc__destroy(&ss_[ss_pos - 1]);
out_free:
free(name);
if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
ret = 0;
out:
dso__set_loaded(dso);
pthread_mutex_unlock(&dso->lock);
nsinfo__mountns_exit(&nsc);
return ret;
}
struct map *map_groups__find_by_name(struct map_groups *mg, const char *name)
{
struct maps *maps = &mg->maps;
struct map *map;
struct rb_node *node;
down_read(&maps->lock);
for (node = maps->names.rb_node; node; ) {
int rc;
map = rb_entry(node, struct map, rb_node_name);
rc = strcmp(map->dso->short_name, name);
if (rc < 0)
node = node->rb_left;
else if (rc > 0)
node = node->rb_right;
else
goto out_unlock;
}
map = NULL;
out_unlock:
up_read(&maps->lock);
return map;
}
int dso__load_vmlinux(struct dso *dso, struct map *map,
const char *vmlinux, bool vmlinux_allocated)
{
int err = -1;
struct symsrc ss;
char symfs_vmlinux[PATH_MAX];
enum dso_binary_type symtab_type;
if (vmlinux[0] == '/')
snprintf(symfs_vmlinux, sizeof(symfs_vmlinux), "%s", vmlinux);
else
symbol__join_symfs(symfs_vmlinux, vmlinux);
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
symtab_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
else
symtab_type = DSO_BINARY_TYPE__VMLINUX;
if (symsrc__init(&ss, dso, symfs_vmlinux, symtab_type))
return -1;
err = dso__load_sym(dso, map, &ss, &ss, 0);
symsrc__destroy(&ss);
if (err > 0) {
if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
dso->binary_type = DSO_BINARY_TYPE__GUEST_VMLINUX;
else
dso->binary_type = DSO_BINARY_TYPE__VMLINUX;
dso__set_long_name(dso, vmlinux, vmlinux_allocated);
dso__set_loaded(dso);
pr_debug("Using %s for symbols\n", symfs_vmlinux);
}
return err;
}
int dso__load_vmlinux_path(struct dso *dso, struct map *map)
{
int i, err = 0;
char *filename = NULL;
pr_debug("Looking at the vmlinux_path (%d entries long)\n",
vmlinux_path__nr_entries + 1);
for (i = 0; i < vmlinux_path__nr_entries; ++i) {
err = dso__load_vmlinux(dso, map, vmlinux_path[i], false);
if (err > 0)
goto out;
}
if (!symbol_conf.ignore_vmlinux_buildid)
filename = dso__build_id_filename(dso, NULL, 0, false);
if (filename != NULL) {
err = dso__load_vmlinux(dso, map, filename, true);
if (err > 0)
goto out;
free(filename);
}
out:
return err;
}
static bool visible_dir_filter(const char *name, struct dirent *d)
{
if (d->d_type != DT_DIR)
return false;
return lsdir_no_dot_filter(name, d);
}
static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz)
{
char kallsyms_filename[PATH_MAX];
int ret = -1;
struct strlist *dirs;
struct str_node *nd;
dirs = lsdir(dir, visible_dir_filter);
if (!dirs)
return -1;
strlist__for_each_entry(nd, dirs) {
scnprintf(kallsyms_filename, sizeof(kallsyms_filename),
"%s/%s/kallsyms", dir, nd->s);
if (!validate_kcore_addresses(kallsyms_filename, map)) {
strlcpy(dir, kallsyms_filename, dir_sz);
ret = 0;
break;
}
}
strlist__delete(dirs);
return ret;
}
/*
* Use open(O_RDONLY) to check readability directly instead of access(R_OK)
* since access(R_OK) only checks with real UID/GID but open() use effective
* UID/GID and actual capabilities (e.g. /proc/kcore requires CAP_SYS_RAWIO).
*/
static bool filename__readable(const char *file)
{
int fd = open(file, O_RDONLY);
if (fd < 0)
return false;
close(fd);
return true;
}
static char *dso__find_kallsyms(struct dso *dso, struct map *map)
{
u8 host_build_id[BUILD_ID_SIZE];
char sbuild_id[SBUILD_ID_SIZE];
bool is_host = false;
char path[PATH_MAX];
if (!dso->has_build_id) {
/*
* Last resort, if we don't have a build-id and couldn't find
* any vmlinux file, try the running kernel kallsyms table.
*/
goto proc_kallsyms;
}
if (sysfs__read_build_id("/sys/kernel/notes", host_build_id,
sizeof(host_build_id)) == 0)
is_host = dso__build_id_equal(dso, host_build_id);
/* Try a fast path for /proc/kallsyms if possible */
if (is_host) {
/*
* Do not check the build-id cache, unless we know we cannot use
* /proc/kcore or module maps don't match to /proc/kallsyms.
* To check readability of /proc/kcore, do not use access(R_OK)
* since /proc/kcore requires CAP_SYS_RAWIO to read and access
* can't check it.
*/
if (filename__readable("/proc/kcore") &&
!validate_kcore_addresses("/proc/kallsyms", map))
goto proc_kallsyms;
}
build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
/* Find kallsyms in build-id cache with kcore */
scnprintf(path, sizeof(path), "%s/%s/%s",
buildid_dir, DSO__NAME_KCORE, sbuild_id);
if (!find_matching_kcore(map, path, sizeof(path)))
return strdup(path);
/* Use current /proc/kallsyms if possible */
if (is_host) {
proc_kallsyms:
return strdup("/proc/kallsyms");
}
/* Finally, find a cache of kallsyms */
if (!build_id_cache__kallsyms_path(sbuild_id, path, sizeof(path))) {
pr_err("No kallsyms or vmlinux with build-id %s was found\n",
sbuild_id);
return NULL;
}
return strdup(path);
}
static int dso__load_kernel_sym(struct dso *dso, struct map *map)
{
int err;
const char *kallsyms_filename = NULL;
char *kallsyms_allocated_filename = NULL;
/*
* Step 1: if the user specified a kallsyms or vmlinux filename, use
* it and only it, reporting errors to the user if it cannot be used.
*
* For instance, try to analyse an ARM perf.data file _without_ a
* build-id, or if the user specifies the wrong path to the right
* vmlinux file, obviously we can't fallback to another vmlinux (a
* x86_86 one, on the machine where analysis is being performed, say),
* or worse, /proc/kallsyms.
*
* If the specified file _has_ a build-id and there is a build-id
* section in the perf.data file, we will still do the expected
* validation in dso__load_vmlinux and will bail out if they don't
* match.
*/
if (symbol_conf.kallsyms_name != NULL) {
kallsyms_filename = symbol_conf.kallsyms_name;
goto do_kallsyms;
}
if (!symbol_conf.ignore_vmlinux && symbol_conf.vmlinux_name != NULL) {
return dso__load_vmlinux(dso, map, symbol_conf.vmlinux_name, false);
}
if (!symbol_conf.ignore_vmlinux && vmlinux_path != NULL) {
err = dso__load_vmlinux_path(dso, map);
if (err > 0)
return err;
}
/* do not try local files if a symfs was given */
if (symbol_conf.symfs[0] != 0)
return -1;
kallsyms_allocated_filename = dso__find_kallsyms(dso, map);
if (!kallsyms_allocated_filename)
return -1;
kallsyms_filename = kallsyms_allocated_filename;
do_kallsyms:
err = dso__load_kallsyms(dso, kallsyms_filename, map);
if (err > 0)
pr_debug("Using %s for symbols\n", kallsyms_filename);
free(kallsyms_allocated_filename);
if (err > 0 && !dso__is_kcore(dso)) {
dso->binary_type = DSO_BINARY_TYPE__KALLSYMS;
dso__set_long_name(dso, DSO__NAME_KALLSYMS, false);
map__fixup_start(map);
map__fixup_end(map);
}
return err;
}
static int dso__load_guest_kernel_sym(struct dso *dso, struct map *map)
{
int err;
const char *kallsyms_filename = NULL;
struct machine *machine;
char path[PATH_MAX];
if (!map->groups) {
pr_debug("Guest kernel map hasn't the point to groups\n");
return -1;
}
machine = map->groups->machine;
if (machine__is_default_guest(machine)) {
/*
* if the user specified a vmlinux filename, use it and only
* it, reporting errors to the user if it cannot be used.
* Or use file guest_kallsyms inputted by user on commandline
*/
if (symbol_conf.default_guest_vmlinux_name != NULL) {
err = dso__load_vmlinux(dso, map,
symbol_conf.default_guest_vmlinux_name,
false);
return err;
}
kallsyms_filename = symbol_conf.default_guest_kallsyms;
if (!kallsyms_filename)
return -1;
} else {
sprintf(path, "%s/proc/kallsyms", machine->root_dir);
kallsyms_filename = path;
}
err = dso__load_kallsyms(dso, kallsyms_filename, map);
if (err > 0)
pr_debug("Using %s for symbols\n", kallsyms_filename);
if (err > 0 && !dso__is_kcore(dso)) {
dso->binary_type = DSO_BINARY_TYPE__GUEST_KALLSYMS;
dso__set_long_name(dso, machine->mmap_name, false);
map__fixup_start(map);
map__fixup_end(map);
}
return err;
}
static void vmlinux_path__exit(void)
{
while (--vmlinux_path__nr_entries >= 0)
zfree(&vmlinux_path[vmlinux_path__nr_entries]);
vmlinux_path__nr_entries = 0;
zfree(&vmlinux_path);
}
static const char * const vmlinux_paths[] = {
"vmlinux",
"/boot/vmlinux"
};
static const char * const vmlinux_paths_upd[] = {
"/boot/vmlinux-%s",
"/usr/lib/debug/boot/vmlinux-%s",
"/lib/modules/%s/build/vmlinux",
"/usr/lib/debug/lib/modules/%s/vmlinux",
"/usr/lib/debug/boot/vmlinux-%s.debug"
};
static int vmlinux_path__add(const char *new_entry)
{
vmlinux_path[vmlinux_path__nr_entries] = strdup(new_entry);
if (vmlinux_path[vmlinux_path__nr_entries] == NULL)
return -1;
++vmlinux_path__nr_entries;
return 0;
}
static int vmlinux_path__init(struct perf_env *env)
{
struct utsname uts;
char bf[PATH_MAX];
char *kernel_version;
unsigned int i;
vmlinux_path = malloc(sizeof(char *) * (ARRAY_SIZE(vmlinux_paths) +
ARRAY_SIZE(vmlinux_paths_upd)));
if (vmlinux_path == NULL)
return -1;
for (i = 0; i < ARRAY_SIZE(vmlinux_paths); i++)
if (vmlinux_path__add(vmlinux_paths[i]) < 0)
goto out_fail;
/* only try kernel version if no symfs was given */
if (symbol_conf.symfs[0] != 0)
return 0;
if (env) {
kernel_version = env->os_release;
} else {
if (uname(&uts) < 0)
goto out_fail;
kernel_version = uts.release;
}
for (i = 0; i < ARRAY_SIZE(vmlinux_paths_upd); i++) {
snprintf(bf, sizeof(bf), vmlinux_paths_upd[i], kernel_version);
if (vmlinux_path__add(bf) < 0)
goto out_fail;
}
return 0;
out_fail:
vmlinux_path__exit();
return -1;
}
int setup_list(struct strlist **list, const char *list_str,
const char *list_name)
{
if (list_str == NULL)
return 0;
*list = strlist__new(list_str, NULL);
if (!*list) {
pr_err("problems parsing %s list\n", list_name);
return -1;
}
symbol_conf.has_filter = true;
return 0;
}
int setup_intlist(struct intlist **list, const char *list_str,
const char *list_name)
{
if (list_str == NULL)
return 0;
*list = intlist__new(list_str);
if (!*list) {
pr_err("problems parsing %s list\n", list_name);
return -1;
}
return 0;
}
static bool symbol__read_kptr_restrict(void)
{
bool value = false;
FILE *fp = fopen("/proc/sys/kernel/kptr_restrict", "r");
if (fp != NULL) {
char line[8];
if (fgets(line, sizeof(line), fp) != NULL)
value = perf_cap__capable(CAP_SYSLOG) ?
(atoi(line) >= 2) :
(atoi(line) != 0);
fclose(fp);
}
/* Per kernel/kallsyms.c:
* we also restrict when perf_event_paranoid > 1 w/o CAP_SYSLOG
*/
if (perf_event_paranoid() > 1 && !perf_cap__capable(CAP_SYSLOG))
value = true;
return value;
}
int symbol__annotation_init(void)
{
if (symbol_conf.init_annotation)
return 0;
if (symbol_conf.initialized) {
pr_err("Annotation needs to be init before symbol__init()\n");
return -1;
}
symbol_conf.priv_size += sizeof(struct annotation);
symbol_conf.init_annotation = true;
return 0;
}
int symbol__init(struct perf_env *env)
{
const char *symfs;
if (symbol_conf.initialized)
return 0;
symbol_conf.priv_size = PERF_ALIGN(symbol_conf.priv_size, sizeof(u64));
symbol__elf_init();
if (symbol_conf.sort_by_name)
symbol_conf.priv_size += (sizeof(struct symbol_name_rb_node) -
sizeof(struct symbol));
if (symbol_conf.try_vmlinux_path && vmlinux_path__init(env) < 0)
return -1;
if (symbol_conf.field_sep && *symbol_conf.field_sep == '.') {
pr_err("'.' is the only non valid --field-separator argument\n");
return -1;
}
if (setup_list(&symbol_conf.dso_list,
symbol_conf.dso_list_str, "dso") < 0)
return -1;
if (setup_list(&symbol_conf.comm_list,
symbol_conf.comm_list_str, "comm") < 0)
goto out_free_dso_list;
if (setup_intlist(&symbol_conf.pid_list,
symbol_conf.pid_list_str, "pid") < 0)
goto out_free_comm_list;
if (setup_intlist(&symbol_conf.tid_list,
symbol_conf.tid_list_str, "tid") < 0)
goto out_free_pid_list;
if (setup_list(&symbol_conf.sym_list,
symbol_conf.sym_list_str, "symbol") < 0)
goto out_free_tid_list;
if (setup_list(&symbol_conf.bt_stop_list,
symbol_conf.bt_stop_list_str, "symbol") < 0)
goto out_free_sym_list;
/*
* A path to symbols of "/" is identical to ""
* reset here for simplicity.
*/
symfs = realpath(symbol_conf.symfs, NULL);
if (symfs == NULL)
symfs = symbol_conf.symfs;
if (strcmp(symfs, "/") == 0)
symbol_conf.symfs = "";
if (symfs != symbol_conf.symfs)
free((void *)symfs);
symbol_conf.kptr_restrict = symbol__read_kptr_restrict();
symbol_conf.initialized = true;
return 0;
out_free_sym_list:
strlist__delete(symbol_conf.sym_list);
out_free_tid_list:
intlist__delete(symbol_conf.tid_list);
out_free_pid_list:
intlist__delete(symbol_conf.pid_list);
out_free_comm_list:
strlist__delete(symbol_conf.comm_list);
out_free_dso_list:
strlist__delete(symbol_conf.dso_list);
return -1;
}
void symbol__exit(void)
{
if (!symbol_conf.initialized)
return;
strlist__delete(symbol_conf.bt_stop_list);
strlist__delete(symbol_conf.sym_list);
strlist__delete(symbol_conf.dso_list);
strlist__delete(symbol_conf.comm_list);
intlist__delete(symbol_conf.tid_list);
intlist__delete(symbol_conf.pid_list);
vmlinux_path__exit();
symbol_conf.sym_list = symbol_conf.dso_list = symbol_conf.comm_list = NULL;
symbol_conf.bt_stop_list = NULL;
symbol_conf.initialized = false;
}
int symbol__config_symfs(const struct option *opt __maybe_unused,
const char *dir, int unset __maybe_unused)
{
char *bf = NULL;
int ret;
symbol_conf.symfs = strdup(dir);
if (symbol_conf.symfs == NULL)
return -ENOMEM;
/* skip the locally configured cache if a symfs is given, and
* config buildid dir to symfs/.debug
*/
ret = asprintf(&bf, "%s/%s", dir, ".debug");
if (ret < 0)
return -ENOMEM;
set_buildid_dir(bf);
free(bf);
return 0;
}
struct mem_info *mem_info__get(struct mem_info *mi)
{
if (mi)
refcount_inc(&mi->refcnt);
return mi;
}
void mem_info__put(struct mem_info *mi)
{
if (mi && refcount_dec_and_test(&mi->refcnt))
free(mi);
}
struct mem_info *mem_info__new(void)
{
struct mem_info *mi = zalloc(sizeof(*mi));
if (mi)
refcount_set(&mi->refcnt, 1);
return mi;
}
struct block_info *block_info__get(struct block_info *bi)
{
if (bi)
refcount_inc(&bi->refcnt);
return bi;
}
void block_info__put(struct block_info *bi)
{
if (bi && refcount_dec_and_test(&bi->refcnt))
free(bi);
}
struct block_info *block_info__new(void)
{
struct block_info *bi = zalloc(sizeof(*bi));
if (bi)
refcount_set(&bi->refcnt, 1);
return bi;
}
Reference in New Issue View Git Blame Copy Permalink