From bbda5ec671d3fe62faefa1cab7270aa586042a4b Mon Sep 17 00:00:00 2001 From: Masahiro Yamada Date: Fri, 30 Nov 2018 10:05:26 +0900 Subject: kbuild: simplify dependency generation for CONFIG_TRIM_UNUSED_KSYMS My main motivation of this commit is to clean up scripts/Kbuild.include and scripts/Makefile.build. Currently, CONFIG_TRIM_UNUSED_KSYMS works with a tricky gimmick; possibly exported symbols are detected by letting $(CPP) replace EXPORT_SYMBOL* with a special string '=== __KSYM_*===', which is post-processed by sed, and passed to fixdep. The extra preprocessing is costly, and hacking cmd_and_fixdep is ugly. I came up with a new way to find exported symbols; insert a dummy symbol __ksym_marker_* to each potentially exported symbol. Those dummy symbols are picked up by $(NM), post-processed by sed, then appended to .*.cmd files. I collected the post-process part to a new shell script scripts/gen_ksymdeps.sh for readability. The dummy symbols are put into the .discard.* section so that the linker script rips them off the final vmlinux or modules. A nice side-effect is building with CONFIG_TRIM_UNUSED_KSYMS will be much faster. Signed-off-by: Masahiro Yamada Reviewed-by: Nicolas Pitre --- scripts/basic/fixdep.c | 31 ++++--------------------------- 1 file changed, 4 insertions(+), 27 deletions(-) (limited to 'scripts/basic') diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c index 850966f3d602..facbd603adf6 100644 --- a/scripts/basic/fixdep.c +++ b/scripts/basic/fixdep.c @@ -105,8 +105,7 @@ static void usage(void) { - fprintf(stderr, "Usage: fixdep [-e] \n"); - fprintf(stderr, " -e insert extra dependencies given on stdin\n"); + fprintf(stderr, "Usage: fixdep \n"); exit(1); } @@ -131,21 +130,6 @@ static void print_dep(const char *m, int slen, const char *dir) printf(".h) \\\n"); } -static void do_extra_deps(void) -{ - char buf[80]; - - while (fgets(buf, sizeof(buf), stdin)) { - int len = strlen(buf); - - if (len < 2 || buf[len - 1] != '\n') { - fprintf(stderr, "fixdep: bad data on stdin\n"); - exit(1); - } - print_dep(buf, len - 1, "include/ksym"); - } -} - struct item { struct item *next; unsigned int len; @@ -293,7 +277,7 @@ static int is_ignored_file(const char *s, int len) * assignments are parsed not only by make, but also by the rather simple * parser in scripts/mod/sumversion.c. */ -static void parse_dep_file(char *m, const char *target, int insert_extra_deps) +static void parse_dep_file(char *m, const char *target) { char *p; int is_last, is_target; @@ -369,9 +353,6 @@ static void parse_dep_file(char *m, const char *target, int insert_extra_deps) exit(1); } - if (insert_extra_deps) - do_extra_deps(); - printf("\n%s: $(deps_%s)\n\n", target, target); printf("$(deps_%s):\n", target); } @@ -379,13 +360,9 @@ static void parse_dep_file(char *m, const char *target, int insert_extra_deps) int main(int argc, char *argv[]) { const char *depfile, *target, *cmdline; - int insert_extra_deps = 0; void *buf; - if (argc == 5 && !strcmp(argv[1], "-e")) { - insert_extra_deps = 1; - argv++; - } else if (argc != 4) + if (argc != 4) usage(); depfile = argv[1]; @@ -395,7 +372,7 @@ int main(int argc, char *argv[]) printf("cmd_%s := %s\n\n", target, cmdline); buf = read_file(depfile); - parse_dep_file(buf, target, insert_extra_deps); + parse_dep_file(buf, target); free(buf); return 0; -- cgit v1.2.3-58-ga151