objtool: Add a statistics mode

Have it print a few numbers which can be used to size the hashtables.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20200324160924.321381240@infradead.org
This commit is contained in:
Peter Zijlstra 2020-03-12 09:26:29 +01:00
parent 65fb11a7f6
commit 1e11f3fdc3
4 changed files with 25 additions and 3 deletions

View file

@ -17,7 +17,7 @@
#include "builtin.h"
#include "check.h"
bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess;
bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats;
static const char * const check_usage[] = {
"objtool check [<options>] file.o",
@ -31,6 +31,7 @@ const struct option check_options[] = {
OPT_BOOLEAN('m', "module", &module, "Indicates the object will be part of a kernel module"),
OPT_BOOLEAN('b', "backtrace", &backtrace, "unwind on error"),
OPT_BOOLEAN('a', "uaccess", &uaccess, "enable uaccess checking"),
OPT_BOOLEAN('s', "stats", &stats, "print statistics"),
OPT_END(),
};

View file

@ -8,7 +8,7 @@
#include <subcmd/parse-options.h>
extern const struct option check_options[];
extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess;
extern bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats;
extern int cmd_check(int argc, const char **argv);
extern int cmd_orc(int argc, const char **argv);

View file

@ -239,6 +239,7 @@ static int decode_instructions(struct objtool_file *file)
struct symbol *func;
unsigned long offset;
struct instruction *insn;
unsigned long nr_insns = 0;
int ret;
for_each_sec(file, sec) {
@ -274,6 +275,7 @@ static int decode_instructions(struct objtool_file *file)
hash_add(file->insn_hash, &insn->hash, insn->offset);
list_add_tail(&insn->list, &file->insn_list);
nr_insns++;
}
list_for_each_entry(func, &sec->symbol_list, list) {
@ -291,6 +293,9 @@ static int decode_instructions(struct objtool_file *file)
}
}
if (stats)
printf("nr_insns: %lu\n", nr_insns);
return 0;
err:

View file

@ -15,6 +15,7 @@
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include "builtin.h"
#include "elf.h"
#include "warn.h"
@ -202,6 +203,9 @@ static int read_sections(struct elf *elf)
sec->len = sec->sh.sh_size;
}
if (stats)
printf("nr_sections: %lu\n", (unsigned long)sections_nr);
/* sanity check, one more call to elf_nextscn() should return NULL */
if (elf_nextscn(elf->elf, s)) {
WARN("section entry mismatch");
@ -299,6 +303,9 @@ static int read_symbols(struct elf *elf)
hash_add(elf->symbol_hash, &sym->hash, sym->idx);
}
if (stats)
printf("nr_symbols: %lu\n", (unsigned long)symbols_nr);
/* Create parent/child links for any cold subfunctions */
list_for_each_entry(sec, &elf->sections, list) {
list_for_each_entry(sym, &sec->symbol_list, list) {
@ -360,6 +367,7 @@ static int read_relas(struct elf *elf)
struct rela *rela;
int i;
unsigned int symndx;
unsigned long nr_rela, max_rela = 0, tot_rela = 0;
list_for_each_entry(sec, &elf->sections, list) {
if (sec->sh.sh_type != SHT_RELA)
@ -374,6 +382,7 @@ static int read_relas(struct elf *elf)
sec->base->rela = sec;
nr_rela = 0;
for (i = 0; i < sec->sh.sh_size / sec->sh.sh_entsize; i++) {
rela = malloc(sizeof(*rela));
if (!rela) {
@ -401,8 +410,15 @@ static int read_relas(struct elf *elf)
list_add_tail(&rela->list, &sec->rela_list);
hash_add(sec->rela_hash, &rela->hash, rela->offset);
nr_rela++;
}
max_rela = max(max_rela, nr_rela);
tot_rela += nr_rela;
}
if (stats) {
printf("max_rela: %lu\n", max_rela);
printf("tot_rela: %lu\n", tot_rela);
}
return 0;