diff mbox series

[v2,06/26] modpost: traverse unresolved symbols in order

Message ID 20220501084032.1025918-7-masahiroy@kernel.org (mailing list archive)
State New, archived
Headers show
Series kbuild: yet another series of cleanups (modpost and LTO) | expand

Commit Message

Masahiro Yamada May 1, 2022, 8:40 a.m. UTC 
Currently, modpost manages unresolved in a singly linked list; it adds
a new node to the head, and traverses the list from new to old.

Use a doubly linked list to keep the order in the symbol table in the
ELF file.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---

(no changes since v1)

 scripts/mod/modpost.c | 20 ++++++++++++++------
 scripts/mod/modpost.h |  2 +-
 2 files changed, 15 insertions(+), 7 deletions(-)

Comments

Nick Desaulniers May 3, 2022, 9:49 p.m. UTC | #1 
On Sun, May 1, 2022 at 1:42 AM Masahiro Yamada <masahiroy@kernel.org> wrote:
>
> Currently, modpost manages unresolved in a singly linked list; it adds
> a new node to the head, and traverses the list from new to old.
>
> Use a doubly linked list to keep the order in the symbol table in the
> ELF file.
>
> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
> ---
>
> (no changes since v1)

Technically, you added a comment. :P
https://lore.kernel.org/linux-kbuild/20220424190811.1678416-11-masahiroy@kernel.org/

>
>  scripts/mod/modpost.c | 20 ++++++++++++++------
>  scripts/mod/modpost.h |  2 +-
>  2 files changed, 15 insertions(+), 7 deletions(-)
>
> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> index abcdb0677775..c7dda4cfa497 100644
> --- a/scripts/mod/modpost.c
> +++ b/scripts/mod/modpost.c
> @@ -185,6 +185,8 @@ static struct module *new_module(const char *modname)
>         mod = NOFAIL(malloc(sizeof(*mod) + strlen(modname) + 1));
>         memset(mod, 0, sizeof(*mod));
>
> +       INIT_LIST_HEAD(&mod->unresolved_symbols);
> +
>         strcpy(mod->name, modname);
>         mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0);
>
> @@ -207,6 +209,7 @@ static struct module *new_module(const char *modname)
>
>  struct symbol {
>         struct symbol *next;
> +       struct list_head list;  /* link to module::unresolved_symbols */

Thanks. ;)
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
diff mbox series

Patch

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index abcdb0677775..c7dda4cfa497 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -185,6 +185,8 @@  static struct module *new_module(const char *modname)
 	mod = NOFAIL(malloc(sizeof(*mod) + strlen(modname) + 1));
 	memset(mod, 0, sizeof(*mod));
 
+	INIT_LIST_HEAD(&mod->unresolved_symbols);
+
 	strcpy(mod->name, modname);
 	mod->is_vmlinux = (strcmp(modname, "vmlinux") == 0);
 
@@ -207,6 +209,7 @@  static struct module *new_module(const char *modname)
 
 struct symbol {
 	struct symbol *next;
+	struct list_head list;	/* link to module::unresolved_symbols */
 	struct module *module;
 	char *namespace;
 	unsigned int crc;
@@ -261,8 +264,12 @@  static struct symbol *new_symbol(const char *name, struct module *module,
 
 static void sym_add_unresolved(const char *name, struct module *mod, bool weak)
 {
-	mod->unres = alloc_symbol(name, mod->unres);
-	mod->unres->weak = weak;
+	struct symbol *sym;
+
+	sym = alloc_symbol(name, NULL);
+	sym->weak = weak;
+
+	list_add_tail(&sym->list, &mod->unresolved_symbols);
 }
 
 static struct symbol *find_symbol(const char *name)
@@ -2156,7 +2163,7 @@  static void check_exports(struct module *mod)
 {
 	struct symbol *s, *exp;
 
-	for (s = mod->unres; s; s = s->next) {
+	list_for_each_entry(s, &mod->unresolved_symbols, list) {
 		const char *basename;
 		exp = find_symbol(s->name);
 		if (!exp) {
@@ -2277,7 +2284,7 @@  static void add_versions(struct buffer *b, struct module *mod)
 	buf_printf(b, "static const struct modversion_info ____versions[]\n");
 	buf_printf(b, "__used __section(\"__versions\") = {\n");
 
-	for (s = mod->unres; s; s = s->next) {
+	list_for_each_entry(s, &mod->unresolved_symbols, list) {
 		if (!s->module)
 			continue;
 		if (!s->crc_valid) {
@@ -2303,13 +2310,14 @@  static void add_depends(struct buffer *b, struct module *mod)
 	int first = 1;
 
 	/* Clear ->seen flag of modules that own symbols needed by this. */
-	for (s = mod->unres; s; s = s->next)
+	list_for_each_entry(s, &mod->unresolved_symbols, list) {
 		if (s->module)
 			s->module->seen = s->module->is_vmlinux;
+	}
 
 	buf_printf(b, "\n");
 	buf_printf(b, "MODULE_INFO(depends, \"");
-	for (s = mod->unres; s; s = s->next) {
+	list_for_each_entry(s, &mod->unresolved_symbols, list) {
 		const char *p;
 		if (!s->module)
 			continue;
diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index d0a8ab60f413..65296eca20a1 100644
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -111,8 +111,8 @@  buf_write(struct buffer *buf, const char *s, int len);
 
 struct module {
 	struct list_head list;
+	struct list_head unresolved_symbols;
 	bool is_gpl_compatible;
-	struct symbol *unres;
 	bool from_dump;		/* true if module was loaded from *.symvers */
 	bool is_vmlinux;
 	bool seen;