Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
objtool: Mark .cold subfunctions
Introduce a flag to identify .cold subfunctions so they can be detected
easier and faster.
Acked-by: Petr Mladek <pmladek@suse.com>
Tested-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
+17
-17
+6
-8
tools/objtool/check.c
+6
-8
tools/objtool/check.c
···
1575
1575
/*
1576
1576
* Cross-function jump.
1577
1577
*/
1578
-
if (func && insn_func(jump_dest) && func != insn_func(jump_dest)) {
1578
+
1579
+
if (func && insn_func(jump_dest) && !func->cold &&
1580
+
insn_func(jump_dest)->cold) {
1579
1581
1580
1582
/*
1581
1583
* For GCC 8+, create parent/child links for any cold
···
1594
1592
* case where the parent function's only reference to a
1595
1593
* subfunction is through a jump table.
1596
1594
*/
1597
-
if (!strstr(func->name, ".cold") &&
1598
-
strstr(insn_func(jump_dest)->name, ".cold")) {
1599
-
func->cfunc = insn_func(jump_dest);
1600
-
insn_func(jump_dest)->pfunc = func;
1601
-
}
1595
+
func->cfunc = insn_func(jump_dest);
1596
+
insn_func(jump_dest)->pfunc = func;
1602
1597
}
1603
1598
1604
1599
if (jump_is_sibling_call(file, insn, jump_dest)) {
···
4065
4066
* If this hole jumps to a .cold function, mark it ignore too.
4066
4067
*/
4067
4068
if (insn->jump_dest && insn_func(insn->jump_dest) &&
4068
-
strstr(insn_func(insn->jump_dest)->name, ".cold")) {
4069
+
insn_func(insn->jump_dest)->cold)
4069
4070
insn_func(insn->jump_dest)->ignore = true;
4070
-
}
4071
4071
}
4072
4072
4073
4073
return false;
+10
-9
tools/objtool/elf.c
+10
-9
tools/objtool/elf.c
···
441
441
list_add(&sym->list, entry);
442
442
elf_hash_add(symbol, &sym->hash, sym->idx);
443
443
elf_hash_add(symbol_name, &sym->name_hash, str_hash(sym->name));
444
+
445
+
if (is_func_sym(sym) && strstr(sym->name, ".cold"))
446
+
sym->cold = 1;
447
+
sym->pfunc = sym->cfunc = sym;
444
448
}
445
449
446
450
static int read_symbols(struct elf *elf)
···
531
527
sec_for_each_sym(sec, sym) {
532
528
char *pname;
533
529
size_t pnamelen;
534
-
if (!is_func_sym(sym))
530
+
531
+
if (!sym->cold)
535
532
continue;
536
-
537
-
if (sym->pfunc == NULL)
538
-
sym->pfunc = sym;
539
-
540
-
if (sym->cfunc == NULL)
541
-
sym->cfunc = sym;
542
533
543
534
coldstr = strstr(sym->name, ".cold");
544
-
if (!coldstr)
545
-
continue;
535
+
if (!coldstr) {
536
+
ERROR("%s(): cold subfunction without \".cold\"?", sym->name);
537
+
return -1;
538
+
}
546
539
547
540
pnamelen = coldstr - sym->name;
548
541
pname = strndup(sym->name, pnamelen);