objtool: Optimize read_sections()
Perf showed that __hash_init() is a significant portion of
read_sections(), so instead of doing a per section rela_hash, use an
elf-wide rela_hash.
Statistics show us there are about 1.1 million relas, so size it
accordingly.
This reduces the objtool on vmlinux.o runtime to a third, from 15 to 5
seconds.
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/20200324160924.739153726@infradead.org
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 6df1bae..54a6043 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -569,8 +569,8 @@ static int add_jump_destinations(struct objtool_file *file)
if (insn->ignore || insn->offset == FAKE_JUMP_OFFSET)
continue;
- rela = find_rela_by_dest_range(insn->sec, insn->offset,
- insn->len);
+ rela = find_rela_by_dest_range(file->elf, insn->sec,
+ insn->offset, insn->len);
if (!rela) {
dest_sec = insn->sec;
dest_off = insn->offset + insn->len + insn->immediate;
@@ -666,8 +666,8 @@ static int add_call_destinations(struct objtool_file *file)
if (insn->type != INSN_CALL)
continue;
- rela = find_rela_by_dest_range(insn->sec, insn->offset,
- insn->len);
+ rela = find_rela_by_dest_range(file->elf, insn->sec,
+ insn->offset, insn->len);
if (!rela) {
dest_off = insn->offset + insn->len + insn->immediate;
insn->call_dest = find_func_by_offset(insn->sec, dest_off);
@@ -796,7 +796,7 @@ static int handle_group_alt(struct objtool_file *file,
*/
if ((insn->offset != special_alt->new_off ||
(insn->type != INSN_CALL && !is_static_jump(insn))) &&
- find_rela_by_dest_range(insn->sec, insn->offset, insn->len)) {
+ find_rela_by_dest_range(file->elf, insn->sec, insn->offset, insn->len)) {
WARN_FUNC("unsupported relocation in alternatives section",
insn->sec, insn->offset);
@@ -1066,8 +1066,8 @@ static struct rela *find_jump_table(struct objtool_file *file,
break;
/* look for a relocation which references .rodata */
- text_rela = find_rela_by_dest_range(insn->sec, insn->offset,
- insn->len);
+ text_rela = find_rela_by_dest_range(file->elf, insn->sec,
+ insn->offset, insn->len);
if (!text_rela || text_rela->sym->type != STT_SECTION ||
!text_rela->sym->sec->rodata)
continue;
@@ -1096,7 +1096,7 @@ static struct rela *find_jump_table(struct objtool_file *file,
* should reference text in the same function as the original
* instruction.
*/
- table_rela = find_rela_by_dest(table_sec, table_offset);
+ table_rela = find_rela_by_dest(file->elf, table_sec, table_offset);
if (!table_rela)
continue;
dest_insn = find_insn(file, table_rela->sym->sec, table_rela->addend);
@@ -1232,7 +1232,7 @@ static int read_unwind_hints(struct objtool_file *file)
for (i = 0; i < sec->len / sizeof(struct unwind_hint); i++) {
hint = (struct unwind_hint *)sec->data->d_buf + i;
- rela = find_rela_by_dest(sec, i * sizeof(*hint));
+ rela = find_rela_by_dest(file->elf, sec, i * sizeof(*hint));
if (!rela) {
WARN("can't find rela for unwind_hints[%d]", i);
return -1;