[PATCH v2 09/26] modpost: dump Module.symvers in the same order of modules.order

Masahiro Yamada
2022-05-01T08:43:45Z

modpost dumps the exported symbols into Module.symvers, but currently
in random order because it iterates in the hash table.

Add a linked list of exported symbols in struct module, so we can
iterate on symbols per module.

This commit makes Module.symvers much more readable; the outer loop in
write_dump() iterates over the modules in the order of modules.order,
and the inner loop dumps symbols in each module.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
---

(no changes since v1)

scripts/mod/modpost.c | 29 +++++++++++++----------------
scripts/mod/modpost.h | 1 +
2 files changed, 14 insertions(+), 16 deletions(-)

diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
index d0cf94e1e984..cd49ef7b5953 100644
--- a/scripts/mod/modpost.c
+++ b/scripts/mod/modpost.c
@@ -185,6 +185,7 @@ 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->exported_symbols);
INIT_LIST_HEAD(&mod->unresolved_symbols);
INIT_LIST_HEAD(&mod->missing_namespaces);
INIT_LIST_HEAD(&mod->imported_namespaces);
@@ -211,7 +212,7 @@ static struct module *new_module(const char *modname)

struct symbol {
struct symbol *next;
- struct list_head list; /* link to module::unresolved_symbols */
+ struct list_head list; /* link to module::exported_symbols or module::unresolved_symbols */
struct module *module;
char *namespace;
unsigned int crc;
@@ -413,6 +414,7 @@ static struct symbol *sym_add_exported(const char *name, struct module *mod,

if (!s) {
s = new_symbol(name, mod, export);
+ list_add_tail(&s->list, &mod->exported_symbols);
} else if (!external_module || s->module->is_vmlinux ||
s->module == mod) {
warn("%s: '%s' exported twice. Previous export was in %s%s\n",
@@ -2456,22 +2458,17 @@ static void read_dump(const char *fname)
static void write_dump(const char *fname)
{
struct buffer buf = { };
- struct symbol *symbol;
- const char *namespace;
- int n;
+ struct module *mod;
+ struct symbol *sym;

- for (n = 0; n < SYMBOL_HASH_SIZE ; n++) {
- symbol = symbolhash[n];
- while (symbol) {
- if (!symbol->module->from_dump) {
- namespace = symbol->namespace;
- buf_printf(&buf, "0x%08x\t%s\t%s\t%s\t%s\n",
- symbol->crc, symbol->name,
- symbol->module->name,
- export_str(symbol->export),
- namespace ? namespace : "");
- }
- symbol = symbol->next;
+ list_for_each_entry(mod, &modules, list) {
+ if (mod->from_dump)
+ continue;
+ list_for_each_entry(sym, &mod->exported_symbols, list) {
+ buf_printf(&buf, "0x%08x\t%s\t%s\t%s\t%s\n",
+ sym->crc, sym->name, mod->name,
+ export_str(sym->export),
+ sym->namespace ?: "");
}
}
write_buf(&buf, fname);
diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
index 2a8c1ad0305e..1c2d6498d764 100644
--- a/scripts/mod/modpost.h
+++ b/scripts/mod/modpost.h
@@ -111,6 +111,7 @@ buf_write(struct buffer *buf, const char *s, int len);

struct module {
struct list_head list;
+ struct list_head exported_symbols;
struct list_head unresolved_symbols;
bool is_gpl_compatible;
bool from_dump; /* true if module was loaded from *.symvers */
--
2.32.0