linux/tools/perf/util/srcline.c
Tony Garnock-Jones be8ecc57f1 perf srcline: Use long-running addr2line per DSO
Invoking addr2line in a separate subprocess, one for each required
lookup, takes a terribly long time.

This patch introduces a long-running addr2line process for each DSO,
*DRAMATICALLY* speeding up runs of perf.

What used to take tens of minutes now takes tens of seconds.

Debian bug report about this issue:

  https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=911815

Signed-off-by: Tony Garnock-Jones <tonyg@leastfixedpoint.com>
Tested-by: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210916120939.453536-1-tonyg@leastfixedpoint.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-10-04 09:29:07 -03:00

921 lines
19 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <inttypes.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/zalloc.h>
#include "util/dso.h"
#include "util/debug.h"
#include "util/callchain.h"
#include "util/symbol_conf.h"
#include "srcline.h"
#include "string2.h"
#include "symbol.h"
#include "subcmd/run-command.h"
bool srcline_full_filename;
static const char *dso__name(struct dso *dso)
{
const char *dso_name;
if (dso->symsrc_filename)
dso_name = dso->symsrc_filename;
else
dso_name = dso->long_name;
if (dso_name[0] == '[')
return NULL;
if (!strncmp(dso_name, "/tmp/perf-", 10))
return NULL;
return dso_name;
}
static 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;
}
/* basename version that takes a const input string */
static const char *gnu_basename(const char *path)
{
const char *base = strrchr(path, '/');
return base ? base + 1 : path;
}
static char *srcline_from_fileline(const char *file, unsigned int line)
{
char *srcline;
if (!file)
return NULL;
if (!srcline_full_filename)
file = gnu_basename(file);
if (asprintf(&srcline, "%s:%u", file, line) < 0)
return NULL;
return srcline;
}
static 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(!base_sym->inlined);
} 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 ? base_sym->binding : 0,
base_sym ? base_sym->type : 0,
funcname);
if (inline_sym)
inline_sym->inlined = 1;
}
free(demangled);
return inline_sym;
}
#define MAX_INLINE_NEST 1024
#ifdef HAVE_LIBBFD_SUPPORT
/*
* Implement addr2line using libbfd.
*/
#define PACKAGE "perf"
#include <bfd.h>
struct a2l_data {
const char *input;
u64 addr;
bool found;
const char *filename;
const char *funcname;
unsigned line;
bfd *abfd;
asymbol **syms;
};
static int bfd_error(const char *string)
{
const char *errmsg;
errmsg = bfd_errmsg(bfd_get_error());
fflush(stdout);
if (string)
pr_debug("%s: %s\n", string, errmsg);
else
pr_debug("%s\n", errmsg);
return -1;
}
static int slurp_symtab(bfd *abfd, struct a2l_data *a2l)
{
long storage;
long symcount;
asymbol **syms;
bfd_boolean dynamic = FALSE;
if ((bfd_get_file_flags(abfd) & HAS_SYMS) == 0)
return bfd_error(bfd_get_filename(abfd));
storage = bfd_get_symtab_upper_bound(abfd);
if (storage == 0L) {
storage = bfd_get_dynamic_symtab_upper_bound(abfd);
dynamic = TRUE;
}
if (storage < 0L)
return bfd_error(bfd_get_filename(abfd));
syms = malloc(storage);
if (dynamic)
symcount = bfd_canonicalize_dynamic_symtab(abfd, syms);
else
symcount = bfd_canonicalize_symtab(abfd, syms);
if (symcount < 0) {
free(syms);
return bfd_error(bfd_get_filename(abfd));
}
a2l->syms = syms;
return 0;
}
static void find_address_in_section(bfd *abfd, asection *section, void *data)
{
bfd_vma pc, vma;
bfd_size_type size;
struct a2l_data *a2l = data;
flagword flags;
if (a2l->found)
return;
#ifdef bfd_get_section_flags
flags = bfd_get_section_flags(abfd, section);
#else
flags = bfd_section_flags(section);
#endif
if ((flags & SEC_ALLOC) == 0)
return;
pc = a2l->addr;
#ifdef bfd_get_section_vma
vma = bfd_get_section_vma(abfd, section);
#else
vma = bfd_section_vma(section);
#endif
#ifdef bfd_get_section_size
size = bfd_get_section_size(section);
#else
size = bfd_section_size(section);
#endif
if (pc < vma || pc >= vma + size)
return;
a2l->found = bfd_find_nearest_line(abfd, section, a2l->syms, pc - vma,
&a2l->filename, &a2l->funcname,
&a2l->line);
if (a2l->filename && !strlen(a2l->filename))
a2l->filename = NULL;
}
static struct a2l_data *addr2line_init(const char *path)
{
bfd *abfd;
struct a2l_data *a2l = NULL;
abfd = bfd_openr(path, NULL);
if (abfd == NULL)
return NULL;
if (!bfd_check_format(abfd, bfd_object))
goto out;
a2l = zalloc(sizeof(*a2l));
if (a2l == NULL)
goto out;
a2l->abfd = abfd;
a2l->input = strdup(path);
if (a2l->input == NULL)
goto out;
if (slurp_symtab(abfd, a2l))
goto out;
return a2l;
out:
if (a2l) {
zfree((char **)&a2l->input);
free(a2l);
}
bfd_close(abfd);
return NULL;
}
static void addr2line_cleanup(struct a2l_data *a2l)
{
if (a2l->abfd)
bfd_close(a2l->abfd);
zfree((char **)&a2l->input);
zfree(&a2l->syms);
free(a2l);
}
static int inline_list__append_dso_a2l(struct dso *dso,
struct inline_node *node,
struct symbol *sym)
{
struct a2l_data *a2l = dso->a2l;
struct symbol *inline_sym = new_inline_sym(dso, sym, a2l->funcname);
char *srcline = NULL;
if (a2l->filename)
srcline = srcline_from_fileline(a2l->filename, a2l->line);
return inline_list__append(inline_sym, srcline, node);
}
static int addr2line(const char *dso_name, u64 addr,
char **file, unsigned int *line, struct dso *dso,
bool unwind_inlines, struct inline_node *node,
struct symbol *sym)
{
int ret = 0;
struct a2l_data *a2l = dso->a2l;
if (!a2l) {
dso->a2l = addr2line_init(dso_name);
a2l = dso->a2l;
}
if (a2l == NULL) {
if (!symbol_conf.disable_add2line_warn)
pr_warning("addr2line_init failed for %s\n", dso_name);
return 0;
}
a2l->addr = addr;
a2l->found = false;
bfd_map_over_sections(a2l->abfd, find_address_in_section, a2l);
if (!a2l->found)
return 0;
if (unwind_inlines) {
int cnt = 0;
if (node && inline_list__append_dso_a2l(dso, node, sym))
return 0;
while (bfd_find_inliner_info(a2l->abfd, &a2l->filename,
&a2l->funcname, &a2l->line) &&
cnt++ < MAX_INLINE_NEST) {
if (a2l->filename && !strlen(a2l->filename))
a2l->filename = NULL;
if (node != NULL) {
if (inline_list__append_dso_a2l(dso, node, sym))
return 0;
// found at least one inline frame
ret = 1;
}
}
}
if (file) {
*file = a2l->filename ? strdup(a2l->filename) : NULL;
ret = *file ? 1 : 0;
}
if (line)
*line = a2l->line;
return ret;
}
void dso__free_a2l(struct dso *dso)
{
struct a2l_data *a2l = dso->a2l;
if (!a2l)
return;
addr2line_cleanup(a2l);
dso->a2l = NULL;
}
#else /* HAVE_LIBBFD_SUPPORT */
struct a2l_subprocess {
struct child_process addr2line;
FILE *to_child;
FILE *from_child;
};
static int filename_split(char *filename, unsigned int *line_nr)
{
char *sep;
sep = strchr(filename, '\n');
if (sep)
*sep = '\0';
if (!strcmp(filename, "??:0"))
return 0;
sep = strchr(filename, ':');
if (sep) {
*sep++ = '\0';
*line_nr = strtoul(sep, NULL, 0);
return 1;
}
return 0;
}
static void addr2line_subprocess_cleanup(struct a2l_subprocess *a2l)
{
if (a2l->addr2line.pid != -1) {
kill(a2l->addr2line.pid, SIGKILL);
finish_command(&a2l->addr2line); /* ignore result, we don't care */
a2l->addr2line.pid = -1;
}
if (a2l->to_child != NULL) {
fclose(a2l->to_child);
a2l->to_child = NULL;
}
if (a2l->from_child != NULL) {
fclose(a2l->from_child);
a2l->from_child = NULL;
}
free(a2l);
}
static struct a2l_subprocess *addr2line_subprocess_init(const char *path)
{
const char *argv[] = { "addr2line", "-e", path, "-i", "-f", NULL };
struct a2l_subprocess *a2l = zalloc(sizeof(*a2l));
int start_command_status = 0;
if (a2l == NULL)
goto out;
a2l->to_child = NULL;
a2l->from_child = NULL;
a2l->addr2line.pid = -1;
a2l->addr2line.in = -1;
a2l->addr2line.out = -1;
a2l->addr2line.no_stderr = 1;
a2l->addr2line.argv = argv;
start_command_status = start_command(&a2l->addr2line);
a2l->addr2line.argv = NULL; /* it's not used after start_command; avoid dangling pointers */
if (start_command_status != 0) {
pr_warning("could not start addr2line for %s: start_command return code %d\n",
path,
start_command_status);
goto out;
}
a2l->to_child = fdopen(a2l->addr2line.in, "w");
if (a2l->to_child == NULL) {
pr_warning("could not open write-stream to addr2line of %s\n", path);
goto out;
}
a2l->from_child = fdopen(a2l->addr2line.out, "r");
if (a2l->from_child == NULL) {
pr_warning("could not open read-stream from addr2line of %s\n", path);
goto out;
}
return a2l;
out:
if (a2l)
addr2line_subprocess_cleanup(a2l);
return NULL;
}
static int read_addr2line_record(struct a2l_subprocess *a2l,
char **function,
char **filename,
unsigned int *line_nr)
{
/*
* Returns:
* -1 ==> error
* 0 ==> sentinel (or other ill-formed) record read
* 1 ==> a genuine record read
*/
char *line = NULL;
size_t line_len = 0;
unsigned int dummy_line_nr = 0;
int ret = -1;
if (function != NULL)
zfree(function);
if (filename != NULL)
zfree(filename);
if (line_nr != NULL)
*line_nr = 0;
if (getline(&line, &line_len, a2l->from_child) < 0 || !line_len)
goto error;
if (function != NULL)
*function = strdup(strim(line));
zfree(&line);
line_len = 0;
if (getline(&line, &line_len, a2l->from_child) < 0 || !line_len)
goto error;
if (filename_split(line, line_nr == NULL ? &dummy_line_nr : line_nr) == 0) {
ret = 0;
goto error;
}
if (filename != NULL)
*filename = strdup(line);
zfree(&line);
line_len = 0;
return 1;
error:
free(line);
if (function != NULL)
zfree(function);
if (filename != NULL)
zfree(filename);
return ret;
}
static int inline_list__append_record(struct dso *dso,
struct inline_node *node,
struct symbol *sym,
const char *function,
const char *filename,
unsigned int line_nr)
{
struct symbol *inline_sym = new_inline_sym(dso, sym, function);
return inline_list__append(inline_sym, srcline_from_fileline(filename, line_nr), node);
}
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 __maybe_unused)
{
struct a2l_subprocess *a2l = dso->a2l;
char *record_function = NULL;
char *record_filename = NULL;
unsigned int record_line_nr = 0;
int record_status = -1;
int ret = 0;
size_t inline_count = 0;
if (!a2l) {
dso->a2l = addr2line_subprocess_init(dso_name);
a2l = dso->a2l;
}
if (a2l == NULL) {
if (!symbol_conf.disable_add2line_warn)
pr_warning("%s %s: addr2line_subprocess_init failed\n", __func__, dso_name);
goto out;
}
/*
* Send our request and then *deliberately* send something that can't be interpreted as
* a valid address to ask addr2line about (namely, ","). This causes addr2line to first
* write out the answer to our request, in an unbounded/unknown number of records, and
* then to write out the lines "??" and "??:0", so that we can detect when it has
* finished giving us anything useful. We have to be careful about the first record,
* though, because it may be genuinely unknown, in which case we'll get two sets of
* "??"/"??:0" lines.
*/
if (fprintf(a2l->to_child, "%016"PRIx64"\n,\n", addr) < 0 || fflush(a2l->to_child) != 0) {
pr_warning("%s %s: could not send request\n", __func__, dso_name);
goto out;
}
switch (read_addr2line_record(a2l, &record_function, &record_filename, &record_line_nr)) {
case -1:
pr_warning("%s %s: could not read first record\n", __func__, dso_name);
goto out;
case 0:
/*
* The first record was invalid, so return failure, but first read another
* record, since we asked a junk question and have to clear the answer out.
*/
switch (read_addr2line_record(a2l, NULL, NULL, NULL)) {
case -1:
pr_warning("%s %s: could not read delimiter record\n", __func__, dso_name);
break;
case 0:
/* As expected. */
break;
default:
pr_warning("%s %s: unexpected record instead of sentinel",
__func__, dso_name);
break;
}
goto out;
default:
break;
}
if (file) {
*file = strdup(record_filename);
ret = 1;
}
if (line_nr)
*line_nr = record_line_nr;
if (unwind_inlines) {
if (node && inline_list__append_record(dso, node, sym,
record_function,
record_filename,
record_line_nr)) {
ret = 0;
goto out;
}
}
/* We have to read the records even if we don't care about the inline info. */
while ((record_status = read_addr2line_record(a2l,
&record_function,
&record_filename,
&record_line_nr)) == 1) {
if (unwind_inlines && node && inline_count++ < MAX_INLINE_NEST) {
if (inline_list__append_record(dso, node, sym,
record_function,
record_filename,
record_line_nr)) {
ret = 0;
goto out;
}
ret = 1; /* found at least one inline frame */
}
}
out:
free(record_function);
free(record_filename);
return ret;
}
void dso__free_a2l(struct dso *dso)
{
struct a2l_subprocess *a2l = dso->a2l;
if (!a2l)
return;
addr2line_subprocess_cleanup(a2l);
dso->a2l = NULL;
}
#endif /* HAVE_LIBBFD_SUPPORT */
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, NULL, NULL, dso, 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)
goto out;
dso_name = dso__name(dso);
if (dso_name == NULL)
goto out;
if (!addr2line(dso_name, addr, &file, &line, dso,
unwind_inlines, NULL, sym))
goto out;
srcline = srcline_from_fileline(file, line);
free(file);
if (!srcline)
goto out;
dso->a2l_fails = 0;
return srcline;
out:
if (dso->a2l_fails && ++dso->a2l_fails > A2L_FAIL_LIMIT) {
dso->has_srcline = 0;
dso__free_a2l(dso);
}
if (!show_addr)
return (show_sym && sym) ?
strndup(sym->name, sym->namelen) : NULL;
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, 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)
goto out;
dso_name = dso__name(dso);
if (dso_name == NULL)
goto out;
if (!addr2line(dso_name, addr, &file, line, dso, true, NULL, NULL))
goto out;
dso->a2l_fails = 0;
return file;
out:
if (dso->a2l_fails && ++dso->a2l_fails > A2L_FAIL_LIMIT) {
dso->has_srcline = 0;
dso__free_a2l(dso);
}
return NULL;
}
void free_srcline(char *srcline)
{
if (srcline && strcmp(srcline, SRCLINE_UNKNOWN) != 0)
free(srcline);
}
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);
free_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 = dso__name(dso);
if (dso_name == NULL)
return NULL;
return addr2inlines(dso_name, addr, dso, sym);
}
void inline_node__delete(struct inline_node *node)
{
struct inline_list *ilist, *tmp;
list_for_each_entry_safe(ilist, tmp, &node->val, list) {
list_del_init(&ilist->list);
free_srcline(ilist->srcline);
/* only the inlined symbols are owned by the list */
if (ilist->symbol && ilist->symbol->inlined)
symbol__delete(ilist->symbol);
free(ilist);
}
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);
}
}