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linuxdebug/tools/perf/util/symbol.c

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// 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__MIXEDUP_UBUNTU_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;
}
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);
}
}
}
/* Update zero-sized symbols using the address of the next symbol */
void symbols__fixup_end(struct rb_root_cached *symbols, bool is_kallsyms)
{
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);
/*
* On some architecture kernel text segment start is located at
* some low memory address, while modules are located at high
* memory addresses (or vice versa). The gap between end of
* kernel text segment and beginning of first module's text
* segment is very big. Therefore do not fill this gap and do
* not assign it to the kernel dso map (kallsyms).
*
* In kallsyms, it determines module symbols using '[' character
* like in:
* ffffffffc1937000 T hdmi_driver_init [snd_hda_codec_hdmi]
*/
if (prev->end == prev->start) {
/* Last kernel/module symbol mapped to end of page */
if (is_kallsyms && (!strchr(prev->name, '[') !=
!strchr(curr->name, '[')))
prev->end = roundup(prev->end + 4096, 4096);
else
prev->end = curr->start;
pr_debug4("%s sym:%s end:%#" PRIx64 "\n",
__func__, prev->name, prev->end);
}
}
/* Last entry */
if (curr->end == curr->start)
curr->end = roundup(curr->start, 4096) + 4096;
}
void maps__fixup_end(struct maps *maps)
{
struct map *prev = NULL, *curr;
down_write(&maps->lock);
maps__for_each_entry(maps, curr) {
if (prev != NULL && !prev->end)
prev->end = curr->start;
prev = curr;
}
/*
* We still haven't the actual symbols, so guess the
* last map final address.
*/
if (curr && !curr->end)
curr->end = ~0ULL;
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;
annotation__init(notes);
}
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)
{
if (symbol_conf.priv_size) {
if (symbol_conf.init_annotation) {
struct annotation *notes = symbol__annotation(sym);
annotation__exit(notes);
}
}
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;
}
}
void dso__delete_symbol(struct dso *dso, struct symbol *sym)
{
rb_erase_cached(&sym->rb_node, &dso->symbols);
symbol__delete(sym);
dso__reset_find_symbol_cache(dso);
}
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);
}
/*
* While we find nice hex chars, build a long_val.
* Return number of chars processed.
*/
static int hex2u64(const char *ptr, u64 *long_val)
{
char *p;
*long_val = strtoull(ptr, &p, 16);
return p - ptr;
}
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[] = {
"acpi_idle_do_entry",
"acpi_processor_ffh_cstate_enter",
"arch_cpu_idle",
"cpu_idle",
"cpu_startup_entry",
"idle_cpu",
"intel_idle",
"default_idle",
"native_safe_halt",
"enter_idle",
"exit_idle",
"mwait_idle",
"mwait_idle_with_hints",
"mwait_idle_with_hints.constprop.0",
"poll_idle",
"ppc64_runlatch_off",
"pseries_dedicated_idle_sleep",
"psw_idle",
"psw_idle_exit",
NULL
};
int i;
static struct strlist *idle_symbols_list;
if (idle_symbols_list)
return strlist__has_entry(idle_symbols_list, name);
idle_symbols_list = strlist__new(NULL, NULL);
for (i = 0; idle_symbols[i]; i++)
strlist__add(idle_symbols_list, idle_symbols[i]);
return strlist__has_entry(idle_symbols_list, name);
}
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;
/* Ignore local symbols for ARM modules */
if (name[0] == '$')
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 maps__split_kallsyms_for_kcore(struct maps *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 = maps__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 maps__split_kallsyms(struct maps *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_SPACE__KERNEL_GUEST &&
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 = maps__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_SPACE__KERNEL_GUEST)
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;
maps__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_SPACE__KERNEL_GUEST &&
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;
}
static int do_validate_kcore_modules(const char *filename, struct maps *kmaps)
{
struct rb_root modules = RB_ROOT;
struct map *old_map;
int err;
err = read_proc_modules(filename, &modules);
if (err)
return err;
maps__for_each_entry(kmaps, old_map) {
struct module_info *mi;
if (!__map__is_kmodule(old_map)) {
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;
}
}
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 maps *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 maps by splitting the new map within the existing map
* regions.
*/
int maps__merge_in(struct maps *kmaps, struct map *new_map)
{
struct map *old_map;
LIST_HEAD(merged);
maps__for_each_entry(kmaps, 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->pgoff += old_map->end - new_map->start;
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->pgoff += old_map->end - new_map->start;
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);
maps__insert(kmaps, old_map);
map__put(old_map);
}
if (new_map) {
maps__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 maps *kmaps = map__kmaps(map);
struct kcore_mapfn_data md;
struct map *old_map, *new_map, *replacement_map = NULL, *next;
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 */
maps__for_each_entry_safe(kmaps, old_map, next) {
/*
* 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))
maps__remove(kmaps, old_map);
}
machine->trampolines_mapped = false;
/* Find the kernel map using the '_stext' symbol */
if (!kallsyms__get_function_start(kallsyms_filename, "_stext", &stext)) {
u64 replacement_size = 0;
list_for_each_entry(new_map, &md.maps, node) {
u64 new_size = new_map->end - new_map->start;
if (!(stext >= new_map->start && stext < new_map->end))
continue;
/*
* On some architectures, ARM64 for example, the kernel
* text can get allocated inside of the vmalloc segment.
* Select the smallest matching segment, in case stext
* falls within more than one in the list.
*/
if (!replacement_map || new_size < replacement_size) {
replacement_map = new_map;
replacement_size = new_size;
}
}
}
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);
maps__remove(kmaps, map);
maps__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 (maps__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_SPACE__KERNEL_GUEST)
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, true);
symbols__fixup_duplicate(&dso->symbols);
if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
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 maps__split_kallsyms_for_kcore(kmap->kmaps, dso);
else
return maps__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;
}
#ifdef HAVE_LIBBFD_SUPPORT
#define PACKAGE 'perf'
#include <bfd.h>
static int bfd_symbols__cmpvalue(const void *a, const void *b)
{
const asymbol *as = *(const asymbol **)a, *bs = *(const asymbol **)b;
if (bfd_asymbol_value(as) != bfd_asymbol_value(bs))
return bfd_asymbol_value(as) - bfd_asymbol_value(bs);
return bfd_asymbol_name(as)[0] - bfd_asymbol_name(bs)[0];
}
static int bfd2elf_binding(asymbol *symbol)
{
if (symbol->flags & BSF_WEAK)
return STB_WEAK;
if (symbol->flags & BSF_GLOBAL)
return STB_GLOBAL;
if (symbol->flags & BSF_LOCAL)
return STB_LOCAL;
return -1;
}
int dso__load_bfd_symbols(struct dso *dso, const char *debugfile)
{
int err = -1;
long symbols_size, symbols_count, i;
asection *section;
asymbol **symbols, *sym;
struct symbol *symbol;
bfd *abfd;
u64 start, len;
abfd = bfd_openr(debugfile, NULL);
if (!abfd)
return -1;
if (!bfd_check_format(abfd, bfd_object)) {
pr_debug2("%s: cannot read %s bfd file.\n", __func__,
dso->long_name);
goto out_close;
}
if (bfd_get_flavour(abfd) == bfd_target_elf_flavour)
goto out_close;
symbols_size = bfd_get_symtab_upper_bound(abfd);
if (symbols_size == 0) {
bfd_close(abfd);
return 0;
}
if (symbols_size < 0)
goto out_close;
symbols = malloc(symbols_size);
if (!symbols)
goto out_close;
symbols_count = bfd_canonicalize_symtab(abfd, symbols);
if (symbols_count < 0)
goto out_free;
section = bfd_get_section_by_name(abfd, ".text");
if (section) {
for (i = 0; i < symbols_count; ++i) {
if (!strcmp(bfd_asymbol_name(symbols[i]), "__ImageBase") ||
!strcmp(bfd_asymbol_name(symbols[i]), "__image_base__"))
break;
}
if (i < symbols_count) {
/* PE symbols can only have 4 bytes, so use .text high bits */
dso->text_offset = section->vma - (u32)section->vma;
dso->text_offset += (u32)bfd_asymbol_value(symbols[i]);
} else {
dso->text_offset = section->vma - section->filepos;
}
}
qsort(symbols, symbols_count, sizeof(asymbol *), bfd_symbols__cmpvalue);
#ifdef bfd_get_section
#define bfd_asymbol_section bfd_get_section
#endif
for (i = 0; i < symbols_count; ++i) {
sym = symbols[i];
section = bfd_asymbol_section(sym);
if (bfd2elf_binding(sym) < 0)
continue;
while (i + 1 < symbols_count &&
bfd_asymbol_section(symbols[i + 1]) == section &&
bfd2elf_binding(symbols[i + 1]) < 0)
i++;
if (i + 1 < symbols_count &&
bfd_asymbol_section(symbols[i + 1]) == section)
len = symbols[i + 1]->value - sym->value;
else
len = section->size - sym->value;
start = bfd_asymbol_value(sym) - dso->text_offset;
symbol = symbol__new(start, len, bfd2elf_binding(sym), STT_FUNC,
bfd_asymbol_name(sym));
if (!symbol)
goto out_free;
symbols__insert(&dso->symbols, symbol);
}
#ifdef bfd_get_section
#undef bfd_asymbol_section
#endif
symbols__fixup_end(&dso->symbols, false);
symbols__fixup_duplicate(&dso->symbols);
dso->adjust_symbols = 1;
err = 0;
out_free:
free(symbols);
out_close:
bfd_close(abfd);
return err;
}
#endif
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__MIXEDUP_UBUNTU_DEBUGINFO:
case DSO_BINARY_TYPE__BUILDID_DEBUGINFO:
case DSO_BINARY_TYPE__OPENEMBEDDED_DEBUGINFO:
return !kmod && dso->kernel == DSO_SPACE__USER;
case DSO_BINARY_TYPE__KALLSYMS:
case DSO_BINARY_TYPE__VMLINUX:
case DSO_BINARY_TYPE__KCORE:
return dso->kernel == DSO_SPACE__KERNEL;
case DSO_BINARY_TYPE__GUEST_KALLSYMS:
case DSO_BINARY_TYPE__GUEST_VMLINUX:
case DSO_BINARY_TYPE__GUEST_KCORE:
return dso->kernel == DSO_SPACE__KERNEL_GUEST;
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__addnew_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__BPF_IMAGE:
case DSO_BINARY_TYPE__OOL:
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 (nsinfo__need_setns(nsi)) {
snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__nstgid(nsi));
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);
nsinfo__clear_need_setns(nnsi);
snprintf(filebuf, bufsz, "/tmp/perf-%d.map", nsinfo__tgid(nnsi));
*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 = NULL;
char *root_dir = (char *) "";
int ss_pos = 0;
struct symsrc ss_[2];
struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
bool kmod;
bool perfmap;
struct build_id bid;
struct nscookie nsc;
char newmapname[PATH_MAX];
const char *map_path = dso->long_name;
mutex_lock(&dso->lock);
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);
/* check again under the dso->lock */
if (dso__loaded(dso)) {
ret = 1;
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;
if (dso->kernel && !kmod) {
if (dso->kernel == DSO_SPACE__KERNEL)
ret = dso__load_kernel_sym(dso, map);
else if (dso->kernel == DSO_SPACE__KERNEL_GUEST)
ret = dso__load_guest_kernel_sym(dso, map);
machine = map__kmaps(map)->machine;
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;
/*
* 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, &bid) > 0)
dso__set_build_id(dso, &bid);
}
/*
* 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 bfdrc = -1;
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 && errno == ENOENT && dso->nsinfo) {
char *new_name = filename_with_chroot(dso->nsinfo->pid,
name);
if (new_name) {
is_reg = is_regular_file(new_name);
strlcpy(name, new_name, PATH_MAX);
free(new_name);
}
}
#ifdef HAVE_LIBBFD_SUPPORT
if (is_reg)
bfdrc = dso__load_bfd_symbols(dso, name);
#endif
if (is_reg && bfdrc < 0)
sirc = symsrc__init(ss, dso, name, symtab_type);
if (nsexit)
nsinfo__mountns_enter(dso->nsinfo, &nsc);
if (bfdrc == 0) {
ret = 0;
break;
}
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);
mutex_unlock(&dso->lock);
nsinfo__mountns_exit(&nsc);
return ret;
}
static int map__strcmp(const void *a, const void *b)
{
const struct map *ma = *(const struct map **)a, *mb = *(const struct map **)b;
return strcmp(ma->dso->short_name, mb->dso->short_name);
}
static int map__strcmp_name(const void *name, const void *b)
{
const struct map *map = *(const struct map **)b;
return strcmp(name, map->dso->short_name);
}
void __maps__sort_by_name(struct maps *maps)
{
qsort(maps->maps_by_name, maps->nr_maps, sizeof(struct map *), map__strcmp);
}
static int map__groups__sort_by_name_from_rbtree(struct maps *maps)
{
struct map *map;
struct map **maps_by_name = realloc(maps->maps_by_name, maps->nr_maps * sizeof(map));
int i = 0;
if (maps_by_name == NULL)
return -1;
maps->maps_by_name = maps_by_name;
maps->nr_maps_allocated = maps->nr_maps;
maps__for_each_entry(maps, map)
maps_by_name[i++] = map;
__maps__sort_by_name(maps);
return 0;
}
static struct map *__maps__find_by_name(struct maps *maps, const char *name)
{
struct map **mapp;
if (maps->maps_by_name == NULL &&
map__groups__sort_by_name_from_rbtree(maps))
return NULL;
mapp = bsearch(name, maps->maps_by_name, maps->nr_maps, sizeof(*mapp), map__strcmp_name);
if (mapp)
return *mapp;
return NULL;
}
struct map *maps__find_by_name(struct maps *maps, const char *name)
{
struct map *map;
down_read(&maps->lock);
if (maps->last_search_by_name && strcmp(maps->last_search_by_name->dso->short_name, name) == 0) {
map = maps->last_search_by_name;
goto out_unlock;
}
/*
* If we have maps->maps_by_name, then the name isn't in the rbtree,
* as maps->maps_by_name mirrors the rbtree when lookups by name are
* made.
*/
map = __maps__find_by_name(maps, name);
if (map || maps->maps_by_name != NULL)
goto out_unlock;
/* Fallback to traversing the rbtree... */
maps__for_each_entry(maps, map)
if (strcmp(map->dso->short_name, name) == 0) {
maps->last_search_by_name = map;
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_SPACE__KERNEL_GUEST)
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_SPACE__KERNEL_GUEST)
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)
{
struct build_id bid;
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", &bid) == 0)
is_host = dso__build_id_equal(dso, &bid);
/* 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->bid, 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;
char *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);
}
/*
* Before checking on common vmlinux locations, check if it's
* stored as standard build id binary (not kallsyms) under
* .debug cache.
*/
if (!symbol_conf.ignore_vmlinux_buildid)
filename = __dso__build_id_filename(dso, NULL, 0, false, false);
if (filename != NULL) {
err = dso__load_vmlinux(dso, map, filename, true);
if (err > 0)
return err;
free(filename);
}
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;
struct machine *machine = map__kmaps(map)->machine;
char path[PATH_MAX];
if (machine->kallsyms_filename) {
kallsyms_filename = machine->kallsyms_filename;
} else 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 int setup_addrlist(struct intlist **addr_list, struct strlist *sym_list)
{
struct str_node *pos, *tmp;
unsigned long val;
char *sep;
const char *end;
int i = 0, err;
*addr_list = intlist__new(NULL);
if (!*addr_list)
return -1;
strlist__for_each_entry_safe(pos, tmp, sym_list) {
errno = 0;
val = strtoul(pos->s, &sep, 16);
if (errno || (sep == pos->s))
continue;
if (*sep != '\0') {
end = pos->s + strlen(pos->s) - 1;
while (end >= sep && isspace(*end))
end--;
if (end >= sep)
continue;
}
err = intlist__add(*addr_list, val);
if (err)
break;
strlist__remove(sym_list, pos);
i++;
}
if (i == 0) {
intlist__delete(*addr_list);
*addr_list = NULL;
}
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 (symbol_conf.sym_list &&
setup_addrlist(&symbol_conf.addr_list, symbol_conf.sym_list) < 0)
goto out_free_sym_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);
intlist__delete(symbol_conf.addr_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);
intlist__delete(symbol_conf.addr_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;
}
/*
* Checks that user supplied symbol kernel files are accessible because
* the default mechanism for accessing elf files fails silently. i.e. if
* debug syms for a build ID aren't found perf carries on normally. When
* they are user supplied we should assume that the user doesn't want to
* silently fail.
*/
int symbol__validate_sym_arguments(void)
{
if (symbol_conf.vmlinux_name &&
access(symbol_conf.vmlinux_name, R_OK)) {
pr_err("Invalid file: %s\n", symbol_conf.vmlinux_name);
return -EINVAL;
}
if (symbol_conf.kallsyms_name &&
access(symbol_conf.kallsyms_name, R_OK)) {
pr_err("Invalid file: %s\n", symbol_conf.kallsyms_name);
return -EINVAL;
}
return 0;
}
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