Files
linux-stable-mirror/tools/perf/util/srcline.c
T
Ian RogersandArnaldo Carvalho de Melo 979e87ab1f perf symbol: Add setters for bitfields sharing a byte to avoid concurrent update issues
A problem with putting bitfields into struct symbol is that other bits in
the symbol could be updated concurrently and only one update to the
underlying storage unit happen, leading to lost updates.

To avoid this, use atomics to atomically read or set part of 16-bits
of flags in the symbol. Add accessors to simplify this.

The idle value has 3 values in preparation for a later change that
will lazily update it.

Assisted-by: Gemini:gemini-3.1-pro-preview
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Honglei Wang <jameshongleiwang@126.com>
Cc: Jan Polensky <japo@linux.ibm.com>
Cc: Sumanth Korikkar <sumanthk@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-03 16:53:45 -03:00

509 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include "srcline.h"
#include "addr2line.h"
#include "dso.h"
#include "callchain.h"
#include "libbfd.h"
#include "llvm.h"
#include "symbol.h"
#include "libdw.h"
#include "debug.h"
#include "util.h"
#include <inttypes.h>
#include <string.h>
#include <linux/string.h>
#include <linux/zalloc.h>
bool srcline_full_filename;
char *srcline__unknown = (char *)"??:0";
static const char *srcline_dso_name(struct dso *dso)
{
const char *dso_name;
if (dso__symsrc_filename(dso))
dso_name = dso__symsrc_filename(dso);
else
dso_name = dso__long_name(dso);
if (dso_name[0] == '[')
return NULL;
if (is_perf_pid_map_name(dso_name))
return NULL;
return dso_name;
}
int inline_list__append(struct symbol *symbol, char *srcline, struct inline_node *node)
{
struct inline_list *ilist;
ilist = zalloc(sizeof(*ilist));
if (ilist == NULL)
return -1;
ilist->symbol = symbol;
ilist->srcline = srcline;
if (callchain_param.order == ORDER_CALLEE)
list_add_tail(&ilist->list, &node->val);
else
list_add(&ilist->list, &node->val);
return 0;
}
int inline_list__append_tail(struct symbol *symbol, char *srcline, struct inline_node *node)
{
struct inline_list *ilist;
ilist = zalloc(sizeof(*ilist));
if (ilist == NULL)
return -1;
ilist->symbol = symbol;
ilist->srcline = srcline;
if (callchain_param.order == ORDER_CALLEE)
list_add(&ilist->list, &node->val);
else
list_add_tail(&ilist->list, &node->val);
return 0;
}
char *srcline_from_fileline(const char *file, unsigned int line)
{
char *srcline;
if (!file)
return NULL;
if (!srcline_full_filename)
file = perf_basename(file);
if (asprintf(&srcline, "%s:%u", file, line) < 0)
return NULL;
return srcline;
}
struct symbol *new_inline_sym(struct dso *dso,
struct symbol *base_sym,
const char *funcname)
{
struct symbol *inline_sym;
char *demangled = NULL;
if (!funcname)
funcname = "??";
if (dso) {
demangled = dso__demangle_sym(dso, 0, funcname);
if (demangled)
funcname = demangled;
}
if (base_sym && strcmp(funcname, base_sym->name) == 0) {
/* reuse the real, existing symbol */
inline_sym = base_sym;
/* ensure that we don't alias an inlined symbol, which could
* lead to double frees in inline_node__delete
*/
assert(!symbol__inlined(base_sym));
} else {
/* create a fake symbol for the inline frame */
inline_sym = symbol__new(base_sym ? base_sym->start : 0,
base_sym ? (base_sym->end - base_sym->start) : 0,
base_sym ? symbol__binding(base_sym) : 0,
base_sym ? symbol__type(base_sym) : 0,
funcname);
if (inline_sym)
symbol__set_inlined(inline_sym, true);
}
free(demangled);
return inline_sym;
}
static int addr2line(const char *dso_name, u64 addr, char **file, unsigned int *line_nr,
struct dso *dso, bool unwind_inlines, struct inline_node *node,
struct symbol *sym)
{
int ret = 0;
if (symbol_conf.addr2line_style[0] == A2L_STYLE_UNKNOWN) {
int i = 0;
/* Default addr2line fallback order. */
#ifdef HAVE_LIBDW_SUPPORT
symbol_conf.addr2line_style[i++] = A2L_STYLE_LIBDW;
#endif
#ifdef HAVE_LIBLLVM_SUPPORT
symbol_conf.addr2line_style[i++] = A2L_STYLE_LLVM;
#endif
#ifdef HAVE_LIBBFD_SUPPORT
symbol_conf.addr2line_style[i++] = A2L_STYLE_LIBBFD;
#endif
symbol_conf.addr2line_style[i++] = A2L_STYLE_CMD;
}
for (size_t i = 0; i < ARRAY_SIZE(symbol_conf.addr2line_style); i++) {
switch (symbol_conf.addr2line_style[i]) {
case A2L_STYLE_LIBDW:
ret = libdw__addr2line(addr, file, line_nr, dso, unwind_inlines,
node, sym);
break;
case A2L_STYLE_LLVM:
ret = llvm__addr2line(dso_name, addr, file, line_nr, dso, unwind_inlines,
node, sym);
break;
case A2L_STYLE_LIBBFD:
ret = libbfd__addr2line(dso_name, addr, file, line_nr, dso, unwind_inlines,
node, sym);
break;
case A2L_STYLE_CMD:
ret = cmd__addr2line(dso_name, addr, file, line_nr, dso, unwind_inlines,
node, sym);
break;
case A2L_STYLE_UNKNOWN:
default:
break;
}
if (ret > 0)
return ret;
}
return 0;
}
int addr2line_configure(const char *var, const char *value, void *cb __maybe_unused)
{
static const char * const a2l_style_names[] = {
[A2L_STYLE_LIBDW] = "libdw",
[A2L_STYLE_LLVM] = "llvm",
[A2L_STYLE_LIBBFD] = "libbfd",
[A2L_STYLE_CMD] = "addr2line",
NULL
};
char *s, *p, *saveptr;
size_t i = 0;
if (strcmp(var, "addr2line.style"))
return 0;
if (!value)
return -1;
s = strdup(value);
if (!s)
return -1;
p = strtok_r(s, ",", &saveptr);
while (p && i < ARRAY_SIZE(symbol_conf.addr2line_style)) {
bool found = false;
char *q = strim(p);
for (size_t j = A2L_STYLE_LIBDW; j < MAX_A2L_STYLE; j++) {
if (!strcasecmp(q, a2l_style_names[j])) {
symbol_conf.addr2line_style[i++] = j;
found = true;
break;
}
}
if (!found)
pr_warning("Unknown addr2line style: %s\n", q);
p = strtok_r(NULL, ",", &saveptr);
}
free(s);
return 0;
}
static struct inline_node *addr2inlines(const char *dso_name, u64 addr,
struct dso *dso, struct symbol *sym)
{
struct inline_node *node;
node = zalloc(sizeof(*node));
if (node == NULL) {
perror("not enough memory for the inline node");
return NULL;
}
INIT_LIST_HEAD(&node->val);
node->addr = addr;
addr2line(dso_name, addr, /*file=*/NULL, /*line_nr=*/NULL, dso,
/*unwind_inlines=*/true, node, sym);
return node;
}
/*
* Number of addr2line failures (without success) before disabling it for that
* dso.
*/
#define A2L_FAIL_LIMIT 123
char *__get_srcline(struct dso *dso, u64 addr, struct symbol *sym,
bool show_sym, bool show_addr, bool unwind_inlines,
u64 ip)
{
char *file = NULL;
unsigned line = 0;
char *srcline;
const char *dso_name;
if (!dso__has_srcline(dso))
goto out;
dso_name = srcline_dso_name(dso);
if (dso_name == NULL)
goto out_err;
if (!addr2line(dso_name, addr, &file, &line, dso,
unwind_inlines, /*node=*/NULL, sym))
goto out_err;
srcline = srcline_from_fileline(file, line);
free(file);
if (!srcline)
goto out_err;
dso__set_a2l_fails(dso, 0);
return srcline;
out_err:
dso__set_a2l_fails(dso, dso__a2l_fails(dso) + 1);
if (dso__a2l_fails(dso) > A2L_FAIL_LIMIT) {
dso__set_has_srcline(dso, false);
dso__free_a2l(dso);
}
out:
if (!show_addr)
return (show_sym && sym) ?
strndup(sym->name, sym->namelen) : SRCLINE_UNKNOWN;
if (sym) {
if (asprintf(&srcline, "%s+%" PRIu64, show_sym ? sym->name : "",
ip - sym->start) < 0)
return SRCLINE_UNKNOWN;
} else if (asprintf(&srcline, "%s[%" PRIx64 "]", dso__short_name(dso), addr) < 0)
return SRCLINE_UNKNOWN;
return srcline;
}
/* Returns filename and fills in line number in line */
char *get_srcline_split(struct dso *dso, u64 addr, unsigned *line)
{
char *file = NULL;
const char *dso_name;
if (!dso__has_srcline(dso))
return NULL;
dso_name = srcline_dso_name(dso);
if (dso_name == NULL)
goto out_err;
if (!addr2line(dso_name, addr, &file, line, dso, /*unwind_inlines=*/true,
/*node=*/NULL, /*sym=*/NULL))
goto out_err;
dso__set_a2l_fails(dso, 0);
return file;
out_err:
dso__set_a2l_fails(dso, dso__a2l_fails(dso) + 1);
if (dso__a2l_fails(dso) > A2L_FAIL_LIMIT) {
dso__set_has_srcline(dso, false);
dso__free_a2l(dso);
}
return NULL;
}
void zfree_srcline(char **srcline)
{
if (*srcline == NULL)
return;
if (*srcline != SRCLINE_UNKNOWN)
free(*srcline);
*srcline = NULL;
}
char *get_srcline(struct dso *dso, u64 addr, struct symbol *sym,
bool show_sym, bool show_addr, u64 ip)
{
return __get_srcline(dso, addr, sym, show_sym, show_addr, false, ip);
}
struct srcline_node {
u64 addr;
char *srcline;
struct rb_node rb_node;
};
void srcline__tree_insert(struct rb_root_cached *tree, u64 addr, char *srcline)
{
struct rb_node **p = &tree->rb_root.rb_node;
struct rb_node *parent = NULL;
struct srcline_node *i, *node;
bool leftmost = true;
node = zalloc(sizeof(struct srcline_node));
if (!node) {
perror("not enough memory for the srcline node");
return;
}
node->addr = addr;
node->srcline = srcline;
while (*p != NULL) {
parent = *p;
i = rb_entry(parent, struct srcline_node, rb_node);
if (addr < i->addr)
p = &(*p)->rb_left;
else {
p = &(*p)->rb_right;
leftmost = false;
}
}
rb_link_node(&node->rb_node, parent, p);
rb_insert_color_cached(&node->rb_node, tree, leftmost);
}
char *srcline__tree_find(struct rb_root_cached *tree, u64 addr)
{
struct rb_node *n = tree->rb_root.rb_node;
while (n) {
struct srcline_node *i = rb_entry(n, struct srcline_node,
rb_node);
if (addr < i->addr)
n = n->rb_left;
else if (addr > i->addr)
n = n->rb_right;
else
return i->srcline;
}
return NULL;
}
void srcline__tree_delete(struct rb_root_cached *tree)
{
struct srcline_node *pos;
struct rb_node *next = rb_first_cached(tree);
while (next) {
pos = rb_entry(next, struct srcline_node, rb_node);
next = rb_next(&pos->rb_node);
rb_erase_cached(&pos->rb_node, tree);
zfree_srcline(&pos->srcline);
zfree(&pos);
}
}
struct inline_node *dso__parse_addr_inlines(struct dso *dso, u64 addr,
struct symbol *sym)
{
const char *dso_name;
dso_name = srcline_dso_name(dso);
if (dso_name == NULL)
return NULL;
return addr2inlines(dso_name, addr, dso, sym);
}
void inline_node__clear_frames(struct inline_node *node)
{
struct inline_list *ilist, *tmp;
if (node == NULL)
return;
list_for_each_entry_safe(ilist, tmp, &node->val, list) {
list_del_init(&ilist->list);
zfree_srcline(&ilist->srcline);
/* only the inlined symbols are owned by the list */
if (ilist->symbol && symbol__inlined(ilist->symbol))
symbol__delete(ilist->symbol);
free(ilist);
}
}
void inline_node__delete(struct inline_node *node)
{
inline_node__clear_frames(node);
free(node);
}
void inlines__tree_insert(struct rb_root_cached *tree,
struct inline_node *inlines)
{
struct rb_node **p = &tree->rb_root.rb_node;
struct rb_node *parent = NULL;
const u64 addr = inlines->addr;
struct inline_node *i;
bool leftmost = true;
while (*p != NULL) {
parent = *p;
i = rb_entry(parent, struct inline_node, rb_node);
if (addr < i->addr)
p = &(*p)->rb_left;
else {
p = &(*p)->rb_right;
leftmost = false;
}
}
rb_link_node(&inlines->rb_node, parent, p);
rb_insert_color_cached(&inlines->rb_node, tree, leftmost);
}
struct inline_node *inlines__tree_find(struct rb_root_cached *tree, u64 addr)
{
struct rb_node *n = tree->rb_root.rb_node;
while (n) {
struct inline_node *i = rb_entry(n, struct inline_node,
rb_node);
if (addr < i->addr)
n = n->rb_left;
else if (addr > i->addr)
n = n->rb_right;
else
return i;
}
return NULL;
}
void inlines__tree_delete(struct rb_root_cached *tree)
{
struct inline_node *pos;
struct rb_node *next = rb_first_cached(tree);
while (next) {
pos = rb_entry(next, struct inline_node, rb_node);
next = rb_next(&pos->rb_node);
rb_erase_cached(&pos->rb_node, tree);
inline_node__delete(pos);
}
}