From 0ae900bef52e9b911e1c262900f9532f8acbe58d Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Thu, 19 Dec 2019 17:33:29 +0900 Subject: [PATCH] kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf Commit bc081dd6e9f6 ("kbuild: generate modules.builtin") added infrastructure to generate modules.builtin, the list of all builtin modules. Basically, it works like this: - Kconfig generates include/config/tristate.conf, the list of tristate CONFIG options with a value in a capital letter. - scripts/Makefile.modbuiltin makes Kbuild descend into directories to collect the information of builtin modules. I am not a big fan of it because Kbuild ends up with traversing the source tree twice. I am not sure how perfectly it should work, but this approach cannot avoid false positives; even if the relevant CONFIG option is tristate, some Makefiles forces obj-m to obj-y. Some examples are: arch/powerpc/platforms/powermac/Makefile: obj-$(CONFIG_NVRAM:m=y) += nvram.o net/ipv6/Makefile: obj-$(subst m,y,$(CONFIG_IPV6)) += inet6_hashtables.o net/netlabel/Makefile: obj-$(subst m,y,$(CONFIG_IPV6)) += netlabel_calipso.o Nobody has complained about (or noticed) it, so it is probably fine to have false positives in modules.builtin. This commit simplifies the implementation. Let's exploit the fact that every module has MODULE_LICENSE(). (modpost shows a warning if MODULE_LICENSE is missing. If so, 0-day bot would already have blocked such a module.) I added MODULE_FILE to . When the code is being compiled as builtin, it will be filled with the file path of the module, and collected into modules.builtin.info. Then, scripts/link-vmlinux.sh extracts the list of builtin modules out of it. This new approach fixes the false-positives above, but adds another type of false-positives; non-modular code may have MODULE_LICENSE() by mistake. This is not a big deal, it is just the code is always orphan. We can clean it up if we like. You can see cleanup examples by: $ git log --grep='make.* explicitly non-modular' To sum up, this commits deletes lots of code, but still produces almost equivalent results. Please note it does not increase the vmlinux size at all. As you can see in include/asm-generic/vmlinux.lds.h, the .modinfo section is discarded in the link stage. Signed-off-by: Masahiro Yamada Signed-off-by: Christian Lamparter --- config/confdata.c | 44 ++------------------------------------------ 1 file changed, 2 insertions(+), 42 deletions(-) diff --git a/config/confdata.c b/config/confdata.c index a124a25..cc18bc4 100644 --- a/config/confdata.c +++ b/config/confdata.c @@ -756,25 +756,6 @@ static struct conf_printer header_printer_cb = .print_comment = header_print_comment, }; -/* - * Tristate printer - * - * This printer is used when generating the `include/generated/tristate.conf' file. - */ -static void -tristate_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg) -{ - - if (sym->type == S_TRISTATE && *value != 'n') - fprintf(fp, "%s%s=%c\n", CONFIG_, sym->name, (char)toupper(*value)); -} - -static struct conf_printer tristate_printer_cb = -{ - .print_symbol = tristate_print_symbol, - .print_comment = kconfig_print_comment, -}; - static void conf_write_symbol(FILE *fp, struct symbol *sym, struct conf_printer *printer, void *printer_arg) { @@ -1108,7 +1089,7 @@ int conf_write_autoconf(int overwrite) struct symbol *sym; const char *name; const char *autoconf_name = conf_get_autoconfig_name(); - FILE *out, *tristate, *out_h, *out_c; + FILE *out, *out_h, *out_c; int i; if (!overwrite && is_present(autoconf_name)) @@ -1123,30 +1104,20 @@ int conf_write_autoconf(int overwrite) if (!out) return 1; - tristate = fopen(".tmpconfig_tristate", "w"); - if (!tristate) { - fclose(out); - return 1; - } - out_h = fopen(".tmpconfig.h", "w"); if (!out_h) { fclose(out); - fclose(tristate); return 1; } out_c = fopen(".tmpconfig.cmake", "w"); if (!out_c) { fclose(out); - fclose(tristate); fclose(out_h); } conf_write_heading(out, &kconfig_printer_cb, NULL); - conf_write_heading(tristate, &tristate_printer_cb, NULL); - conf_write_heading(out_h, &header_printer_cb, NULL); conf_write_heading(out_c, &kconfig_printer_cmake_cb, NULL); @@ -1156,17 +1127,14 @@ int conf_write_autoconf(int overwrite) if (!(sym->flags & SYMBOL_WRITE) || !sym->name) continue; - /* write symbol to auto.conf, tristate and header files */ + /* write symbol to auto.conf and header files */ conf_write_symbol(out, sym, &kconfig_printer_cb, (void *)1); - conf_write_symbol(tristate, sym, &tristate_printer_cb, (void *)1); - conf_write_symbol(out_h, sym, &header_printer_cb, NULL); conf_write_symbol(out_c, sym, &kconfig_printer_cmake_cb, NULL); } fclose(out); - fclose(tristate); fclose(out_h); fclose(out_c); @@ -1178,14 +1146,6 @@ int conf_write_autoconf(int overwrite) if (rename(".tmpconfig.h", name)) return 1; - name = getenv("KCONFIG_TRISTATE"); - if (!name) - name = "include/generated/tristate.conf"; - if (make_parent_dir(name)) - return 1; - if (rename(".tmpconfig_tristate", name)) - return 1; - if (make_parent_dir(autoconf_name)) return 1; -- 2.31.1