diff --git a/include/linux/marker.h b/include/linux/marker.h index b5f95637f289..5df879dc3776 100644 --- a/include/linux/marker.h +++ b/include/linux/marker.h @@ -61,15 +61,12 @@ struct marker { */ #define __trace_mark(name, call_private, format, args...) \ do { \ - static const char __mstrtab_name_##name[] \ + static const char __mstrtab_##name[] \ __attribute__((section("__markers_strings"))) \ - = #name; \ - static const char __mstrtab_format_##name[] \ - __attribute__((section("__markers_strings"))) \ - = format; \ + = #name "\0" format; \ static struct marker __mark_##name \ __attribute__((section("__markers"), aligned(8))) = \ - { __mstrtab_name_##name, __mstrtab_format_##name, \ + { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)], \ 0, 0, marker_probe_cb, \ { __mark_empty_function, NULL}, NULL }; \ __mark_check_format(format, ## args); \ diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 65e707e1ffc3..cfc004e04417 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -13,6 +13,7 @@ # 2) modpost is then used to # 3) create one .mod.c file pr. module # 4) create one Module.symvers file with CRC for all exported symbols +# 4a) [CONFIG_MARKERS] create one Module.markers file listing defined markers # 5) compile all .mod.c files # 6) final link of the module to a file @@ -45,6 +46,10 @@ include scripts/Makefile.lib kernelsymfile := $(objtree)/Module.symvers modulesymfile := $(firstword $(KBUILD_EXTMOD))/Module.symvers +kernelmarkersfile := $(objtree)/Module.markers +modulemarkersfile := $(firstword $(KBUILD_EXTMOD))/Module.markers + +markersfile = $(if $(KBUILD_EXTMOD),$(modulemarkersfile),$(kernelmarkersfile)) # Step 1), find all modules listed in $(MODVERDIR)/ __modules := $(sort $(shell grep -h '\.ko' /dev/null $(wildcard $(MODVERDIR)/*.mod))) @@ -63,6 +68,8 @@ modpost = scripts/mod/modpost \ $(if $(KBUILD_EXTMOD),-I $(modulesymfile)) \ $(if $(KBUILD_EXTMOD),-o $(modulesymfile)) \ $(if $(CONFIG_DEBUG_SECTION_MISMATCH),,-S) \ + $(if $(CONFIG_MARKERS),-K $(kernelmarkersfile)) \ + $(if $(CONFIG_MARKERS),-M $(markersfile)) \ $(if $(KBUILD_EXTMOD)$(KBUILD_MODPOST_WARN),-w) quiet_cmd_modpost = MODPOST $(words $(filter-out vmlinux FORCE, $^)) modules @@ -82,6 +89,10 @@ vmlinux.o: FORCE $(symverfile): __modpost ; $(modules:.ko=.mod.c): __modpost ; +ifdef CONFIG_MARKERS +$(markersfile): __modpost ; +endif + # Step 5), compile all *.mod.c files diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c index dbe1fb5e8cc0..61742771c65d 100644 --- a/scripts/mod/modpost.c +++ b/scripts/mod/modpost.c @@ -11,6 +11,8 @@ * Usage: modpost vmlinux module1.o module2.o ... */ +#define _GNU_SOURCE +#include #include #include "modpost.h" #include "../../include/linux/license.h" @@ -435,6 +437,8 @@ static int parse_elf(struct elf_info *info, const char *filename) info->export_unused_gpl_sec = i; else if (strcmp(secname, "__ksymtab_gpl_future") == 0) info->export_gpl_future_sec = i; + else if (strcmp(secname, "__markers_strings") == 0) + info->markers_strings_sec = i; if (sechdrs[i].sh_type != SHT_SYMTAB) continue; @@ -1470,6 +1474,62 @@ static void check_sec_ref(struct module *mod, const char *modname, } } +static void get_markers(struct elf_info *info, struct module *mod) +{ + const Elf_Shdr *sh = &info->sechdrs[info->markers_strings_sec]; + const char *strings = (const char *) info->hdr + sh->sh_offset; + const Elf_Sym *sym, *first_sym, *last_sym; + size_t n; + + if (!info->markers_strings_sec) + return; + + /* + * First count the strings. We look for all the symbols defined + * in the __markers_strings section named __mstrtab_*. For + * these local names, the compiler puts a random .NNN suffix on, + * so the names don't correspond exactly. + */ + first_sym = last_sym = NULL; + n = 0; + for (sym = info->symtab_start; sym < info->symtab_stop; sym++) + if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT && + sym->st_shndx == info->markers_strings_sec && + !strncmp(info->strtab + sym->st_name, + "__mstrtab_", sizeof "__mstrtab_" - 1)) { + if (first_sym == NULL) + first_sym = sym; + last_sym = sym; + ++n; + } + + if (n == 0) + return; + + /* + * Now collect each name and format into a line for the output. + * Lines look like: + * marker_name vmlinux marker %s format %d + * The format string after the second \t can use whitespace. + */ + mod->markers = NOFAIL(malloc(sizeof mod->markers[0] * n)); + mod->nmarkers = n; + + n = 0; + for (sym = first_sym; sym <= last_sym; sym++) + if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT && + sym->st_shndx == info->markers_strings_sec && + !strncmp(info->strtab + sym->st_name, + "__mstrtab_", sizeof "__mstrtab_" - 1)) { + const char *name = strings + sym->st_value; + const char *fmt = strchr(name, '\0') + 1; + char *line = NULL; + asprintf(&line, "%s\t%s\t%s\n", name, mod->name, fmt); + NOFAIL(line); + mod->markers[n++] = line; + } +} + static void read_symbols(char *modname) { const char *symname; @@ -1521,6 +1581,8 @@ static void read_symbols(char *modname) get_src_version(modname, mod->srcversion, sizeof(mod->srcversion)-1); + get_markers(&info, mod); + parse_elf_finish(&info); /* Our trick to get versioning for struct_module - it's @@ -1867,16 +1929,104 @@ static void write_dump(const char *fname) write_if_changed(&buf, fname); } +static void add_marker(struct module *mod, const char *name, const char *fmt) +{ + char *line = NULL; + asprintf(&line, "%s\t%s\t%s\n", name, mod->name, fmt); + NOFAIL(line); + + mod->markers = NOFAIL(realloc(mod->markers, ((mod->nmarkers + 1) * + sizeof mod->markers[0]))); + mod->markers[mod->nmarkers++] = line; +} + +static void read_markers(const char *fname) +{ + unsigned long size, pos = 0; + void *file = grab_file(fname, &size); + char *line; + + if (!file) /* No old markers, silently ignore */ + return; + + while ((line = get_next_line(&pos, file, size))) { + char *marker, *modname, *fmt; + struct module *mod; + + marker = line; + modname = strchr(marker, '\t'); + if (!modname) + goto fail; + *modname++ = '\0'; + fmt = strchr(modname, '\t'); + if (!fmt) + goto fail; + *fmt++ = '\0'; + if (*marker == '\0' || *modname == '\0') + goto fail; + + mod = find_module(modname); + if (!mod) { + if (is_vmlinux(modname)) + have_vmlinux = 1; + mod = new_module(NOFAIL(strdup(modname))); + mod->skip = 1; + } + + add_marker(mod, marker, fmt); + } + return; +fail: + fatal("parse error in markers list file\n"); +} + +static int compare_strings(const void *a, const void *b) +{ + return strcmp(*(const char **) a, *(const char **) b); +} + +static void write_markers(const char *fname) +{ + struct buffer buf = { }; + struct module *mod; + size_t i; + + for (mod = modules; mod; mod = mod->next) + if ((!external_module || !mod->skip) && mod->markers != NULL) { + /* + * Sort the strings so we can skip duplicates when + * we write them out. + */ + qsort(mod->markers, mod->nmarkers, + sizeof mod->markers[0], &compare_strings); + for (i = 0; i < mod->nmarkers; ++i) { + char *line = mod->markers[i]; + buf_write(&buf, line, strlen(line)); + while (i + 1 < mod->nmarkers && + !strcmp(mod->markers[i], + mod->markers[i + 1])) + free(mod->markers[i++]); + free(mod->markers[i]); + } + free(mod->markers); + mod->markers = NULL; + } + + write_if_changed(&buf, fname); +} + int main(int argc, char **argv) { struct module *mod; struct buffer buf = { }; char *kernel_read = NULL, *module_read = NULL; char *dump_write = NULL; + char *markers_read = NULL; + char *markers_write = NULL; int opt; int err; - while ((opt = getopt(argc, argv, "i:I:msSo:aw")) != -1) { + while ((opt = getopt(argc, argv, "i:I:msSo:awM:K:")) != -1) { switch (opt) { case 'i': kernel_read = optarg; @@ -1903,6 +2053,12 @@ int main(int argc, char **argv) case 'w': warn_unresolved = 1; break; + case 'M': + markers_write = optarg; + break; + case 'K': + markers_read = optarg; + break; default: exit(1); } @@ -1950,5 +2106,11 @@ int main(int argc, char **argv) "'make CONFIG_DEBUG_SECTION_MISMATCH=y'\n", sec_mismatch_count); + if (markers_read) + read_markers(markers_read); + + if (markers_write) + write_markers(markers_write); + return err; } diff --git a/scripts/mod/modpost.h b/scripts/mod/modpost.h index 999f15e0e008..565c5872407e 100644 --- a/scripts/mod/modpost.h +++ b/scripts/mod/modpost.h @@ -112,6 +112,8 @@ struct module { int has_init; int has_cleanup; struct buffer dev_table_buf; + char **markers; + size_t nmarkers; char srcversion[25]; }; @@ -126,6 +128,7 @@ struct elf_info { Elf_Section export_gpl_sec; Elf_Section export_unused_gpl_sec; Elf_Section export_gpl_future_sec; + Elf_Section markers_strings_sec; const char *strtab; char *modinfo; unsigned int modinfo_len;