On Sun, Apr 24, 2022 at 12:09 PM Masahiro Yamada <masahiroy@xxxxxxxxxx> wrote:
>
> Currently, modpost manages unresolved in a singly liked list; it adds
s/liked/linked/
> 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@xxxxxxxxxx>
> ---
>
> 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 1c7d2831e89d..e1eb188d6282 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);
> mod->gpl_compatible = true;
> @@ -201,6 +203,7 @@ static struct module *new_module(const char *modname)
>
> struct symbol {
> struct symbol *next;
> + struct list_head list;
Isn't `list` meant to replace `next`?
> struct module *module;
> unsigned int crc;
> bool crc_valid;
> @@ -255,8 +258,12 @@ 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);
Because I was curious here why NULL was passed, rather than remove the
assignment to struct symbol's next member in alloc_symbol.
I get why you replace the `unres` member of struct module. I guess I'm
curious then why yet another list is added to struct symbol, rather
than replace the next member.
Also, does adding a struct list_head member really not specify the
_type_ of the next element? I guess when I look at the definition of
struct module, at the member unresolved symbols, I don't know whether
it's a list of struct module* or a list of struct symbol*.
<snip>
> diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h
> index c3b5d2f0e2bb..6a90bfc08458 100644
> --- a/scripts/mod/modpost.h
> +++ b/scripts/mod/modpost.h
> @@ -117,7 +117,7 @@ struct namespace_list {
> struct module {
> struct list_head list;
> int gpl_compatible;
> - struct symbol *unres;
> + struct list_head unresolved_symbols;
> bool from_dump; /* true if module was loaded from *.symvers */
> bool is_vmlinux;
> bool seen;
> --
> 2.32.0
>
--
Thanks,
~Nick Desaulniers
