From af5406895a05720a879dc33e2f4878fa503e81b3 Mon Sep 17 00:00:00 2001 From: Richard Kennedy Date: Tue, 22 Jul 2008 19:24:26 -0500 Subject: module: reorder struct module to save space on 64 bit builds reorder struct module to save space on 64 bit builds. saves 1 cacheline_size (128 on default x86_64 & 64 on AMD Opteron/athlon) when CONFIG_MODULE_UNLOAD=y. Signed-off-by: Richard Kennedy Signed-off-by: Rusty Russell --- include/linux/module.h | 42 ++++++++++++++++++++++-------------------- 1 file changed, 22 insertions(+), 20 deletions(-) (limited to 'include/linux/module.h') diff --git a/include/linux/module.h b/include/linux/module.h index 3e03b1acbc94..63f0eb69e214 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -249,27 +249,28 @@ struct module /* Exported symbols */ const struct kernel_symbol *syms; - unsigned int num_syms; const unsigned long *crcs; + unsigned int num_syms; /* GPL-only exported symbols. */ - const struct kernel_symbol *gpl_syms; unsigned int num_gpl_syms; + const struct kernel_symbol *gpl_syms; const unsigned long *gpl_crcs; /* unused exported symbols. */ const struct kernel_symbol *unused_syms; - unsigned int num_unused_syms; const unsigned long *unused_crcs; + unsigned int num_unused_syms; + /* GPL-only, unused exported symbols. */ - const struct kernel_symbol *unused_gpl_syms; unsigned int num_unused_gpl_syms; + const struct kernel_symbol *unused_gpl_syms; const unsigned long *unused_gpl_crcs; /* symbols that will be GPL-only in the near future. */ const struct kernel_symbol *gpl_future_syms; - unsigned int num_gpl_future_syms; const unsigned long *gpl_future_crcs; + unsigned int num_gpl_future_syms; /* Exception table */ unsigned int num_exentries; @@ -300,23 +301,9 @@ struct module #ifdef CONFIG_GENERIC_BUG /* Support for BUG */ + unsigned num_bugs; struct list_head bug_list; struct bug_entry *bug_table; - unsigned num_bugs; -#endif - -#ifdef CONFIG_MODULE_UNLOAD - /* Reference counts */ - struct module_ref ref[NR_CPUS]; - - /* What modules depend on me? */ - struct list_head modules_which_use_me; - - /* Who is waiting for us to be unloaded */ - struct task_struct *waiter; - - /* Destruction function. */ - void (*exit)(void); #endif #ifdef CONFIG_KALLSYMS @@ -342,6 +329,21 @@ struct module struct marker *markers; unsigned int num_markers; #endif + +#ifdef CONFIG_MODULE_UNLOAD + /* What modules depend on me? */ + struct list_head modules_which_use_me; + + /* Who is waiting for us to be unloaded */ + struct task_struct *waiter; + + /* Destruction function. */ + void (*exit)(void); + + /* Reference counts */ + struct module_ref ref[NR_CPUS]; +#endif + }; #ifndef MODULE_ARCH_INIT #define MODULE_ARCH_INIT {} -- cgit v1.2.3 From f7f5b67557eac1131ba6532522e3c50eced34238 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Tue, 22 Jul 2008 19:24:26 -0500 Subject: Shrink struct module: CONFIG_UNUSED_SYMBOLS ifdefs module.c and module.h conatains code for finding exported symbols which are declared with EXPORT_UNUSED_SYMBOL, and this code is compiled in even if CONFIG_UNUSED_SYMBOLS is not set and thus there can be no EXPORT_UNUSED_SYMBOLs in modules anyway (because EXPORT_UNUSED_SYMBOL(x) are compiled out to nothing then). This patch adds required #ifdefs. Signed-off-by: Denys Vlasenko Signed-off-by: Rusty Russell --- include/linux/module.h | 2 ++ init/Kconfig | 4 ++-- kernel/module.c | 49 ++++++++++++++++++++++++++++++++++--------------- 3 files changed, 38 insertions(+), 17 deletions(-) (limited to 'include/linux/module.h') diff --git a/include/linux/module.h b/include/linux/module.h index 63f0eb69e214..a860a2c1f379 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -257,6 +257,7 @@ struct module const struct kernel_symbol *gpl_syms; const unsigned long *gpl_crcs; +#ifdef CONFIG_UNUSED_SYMBOLS /* unused exported symbols. */ const struct kernel_symbol *unused_syms; const unsigned long *unused_crcs; @@ -266,6 +267,7 @@ struct module unsigned int num_unused_gpl_syms; const struct kernel_symbol *unused_gpl_syms; const unsigned long *unused_gpl_crcs; +#endif /* symbols that will be GPL-only in the near future. */ const struct kernel_symbol *gpl_future_syms; diff --git a/init/Kconfig b/init/Kconfig index 6199d1120900..c8578f9ee31d 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -856,8 +856,8 @@ config MODULE_UNLOAD help Without this option you will not be able to unload any modules (note that some modules may not be unloadable - anyway), which makes your kernel slightly smaller and - simpler. If unsure, say Y. + anyway), which makes your kernel smaller, faster + and simpler. If unsure, say Y. config MODULE_FORCE_UNLOAD bool "Forced module unloading" diff --git a/kernel/module.c b/kernel/module.c index c51c089c666e..ea9580521eb1 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -134,17 +134,19 @@ extern const struct kernel_symbol __start___ksymtab_gpl[]; extern const struct kernel_symbol __stop___ksymtab_gpl[]; extern const struct kernel_symbol __start___ksymtab_gpl_future[]; extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; -extern const struct kernel_symbol __start___ksymtab_unused[]; -extern const struct kernel_symbol __stop___ksymtab_unused[]; -extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; -extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; extern const struct kernel_symbol __start___ksymtab_gpl_future[]; extern const struct kernel_symbol __stop___ksymtab_gpl_future[]; extern const unsigned long __start___kcrctab[]; extern const unsigned long __start___kcrctab_gpl[]; extern const unsigned long __start___kcrctab_gpl_future[]; +#ifdef CONFIG_UNUSED_SYMBOLS +extern const struct kernel_symbol __start___ksymtab_unused[]; +extern const struct kernel_symbol __stop___ksymtab_unused[]; +extern const struct kernel_symbol __start___ksymtab_unused_gpl[]; +extern const struct kernel_symbol __stop___ksymtab_unused_gpl[]; extern const unsigned long __start___kcrctab_unused[]; extern const unsigned long __start___kcrctab_unused_gpl[]; +#endif #ifndef CONFIG_MODVERSIONS #define symversion(base, idx) NULL @@ -198,12 +200,14 @@ static bool each_symbol(bool (*fn)(const struct symsearch *arr, { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future, __start___kcrctab_gpl_future, WILL_BE_GPL_ONLY, false }, +#ifdef CONFIG_UNUSED_SYMBOLS { __start___ksymtab_unused, __stop___ksymtab_unused, __start___kcrctab_unused, NOT_GPL_ONLY, true }, { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl, __start___kcrctab_unused_gpl, GPL_ONLY, true }, +#endif }; if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data)) @@ -220,6 +224,7 @@ static bool each_symbol(bool (*fn)(const struct symsearch *arr, mod->gpl_future_syms + mod->num_gpl_future_syms, mod->gpl_future_crcs, WILL_BE_GPL_ONLY, false }, +#ifdef CONFIG_UNUSED_SYMBOLS { mod->unused_syms, mod->unused_syms + mod->num_unused_syms, mod->unused_crcs, @@ -228,6 +233,7 @@ static bool each_symbol(bool (*fn)(const struct symsearch *arr, mod->unused_gpl_syms + mod->num_unused_gpl_syms, mod->unused_gpl_crcs, GPL_ONLY, true }, +#endif }; if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data)) @@ -270,6 +276,7 @@ static bool find_symbol_in_section(const struct symsearch *syms, } } +#ifdef CONFIG_UNUSED_SYMBOLS if (syms->unused && fsa->warn) { printk(KERN_WARNING "Symbol %s is marked as UNUSED, " "however this module is using it.\n", fsa->name); @@ -281,6 +288,7 @@ static bool find_symbol_in_section(const struct symsearch *syms, "mailinglist together with submitting your code for " "inclusion.\n"); } +#endif fsa->owner = owner; fsa->crc = symversion(syms->crcs, symnum); @@ -1476,8 +1484,10 @@ static int verify_export_symbols(struct module *mod) { mod->syms, mod->num_syms }, { mod->gpl_syms, mod->num_gpl_syms }, { mod->gpl_future_syms, mod->num_gpl_future_syms }, +#ifdef CONFIG_UNUSED_SYMBOLS { mod->unused_syms, mod->num_unused_syms }, { mod->unused_gpl_syms, mod->num_unused_gpl_syms }, +#endif }; for (i = 0; i < ARRAY_SIZE(arr); i++) { @@ -1795,10 +1805,12 @@ static struct module *load_module(void __user *umod, unsigned int gplfutureindex; unsigned int gplfuturecrcindex; unsigned int unwindex = 0; +#ifdef CONFIG_UNUSED_SYMBOLS unsigned int unusedindex; unsigned int unusedcrcindex; unsigned int unusedgplindex; unsigned int unusedgplcrcindex; +#endif unsigned int markersindex; unsigned int markersstringsindex; struct module *mod; @@ -1881,13 +1893,15 @@ static struct module *load_module(void __user *umod, exportindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab"); gplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl"); gplfutureindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_gpl_future"); - unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused"); - unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl"); crcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab"); gplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl"); gplfuturecrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_gpl_future"); +#ifdef CONFIG_UNUSED_SYMBOLS + unusedindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused"); + unusedgplindex = find_sec(hdr, sechdrs, secstrings, "__ksymtab_unused_gpl"); unusedcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused"); unusedgplcrcindex = find_sec(hdr, sechdrs, secstrings, "__kcrctab_unused_gpl"); +#endif setupindex = find_sec(hdr, sechdrs, secstrings, "__param"); exindex = find_sec(hdr, sechdrs, secstrings, "__ex_table"); obsparmindex = find_sec(hdr, sechdrs, secstrings, "__obsparm"); @@ -2049,14 +2063,15 @@ static struct module *load_module(void __user *umod, mod->gpl_crcs = (void *)sechdrs[gplcrcindex].sh_addr; mod->num_gpl_future_syms = sechdrs[gplfutureindex].sh_size / sizeof(*mod->gpl_future_syms); - mod->num_unused_syms = sechdrs[unusedindex].sh_size / - sizeof(*mod->unused_syms); - mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size / - sizeof(*mod->unused_gpl_syms); mod->gpl_future_syms = (void *)sechdrs[gplfutureindex].sh_addr; if (gplfuturecrcindex) mod->gpl_future_crcs = (void *)sechdrs[gplfuturecrcindex].sh_addr; +#ifdef CONFIG_UNUSED_SYMBOLS + mod->num_unused_syms = sechdrs[unusedindex].sh_size / + sizeof(*mod->unused_syms); + mod->num_unused_gpl_syms = sechdrs[unusedgplindex].sh_size / + sizeof(*mod->unused_gpl_syms); mod->unused_syms = (void *)sechdrs[unusedindex].sh_addr; if (unusedcrcindex) mod->unused_crcs = (void *)sechdrs[unusedcrcindex].sh_addr; @@ -2064,13 +2079,17 @@ static struct module *load_module(void __user *umod, if (unusedgplcrcindex) mod->unused_gpl_crcs = (void *)sechdrs[unusedgplcrcindex].sh_addr; +#endif #ifdef CONFIG_MODVERSIONS - if ((mod->num_syms && !crcindex) || - (mod->num_gpl_syms && !gplcrcindex) || - (mod->num_gpl_future_syms && !gplfuturecrcindex) || - (mod->num_unused_syms && !unusedcrcindex) || - (mod->num_unused_gpl_syms && !unusedgplcrcindex)) { + if ((mod->num_syms && !crcindex) + || (mod->num_gpl_syms && !gplcrcindex) + || (mod->num_gpl_future_syms && !gplfuturecrcindex) +#ifdef CONFIG_UNUSED_SYMBOLS + || (mod->num_unused_syms && !unusedcrcindex) + || (mod->num_unused_gpl_syms && !unusedgplcrcindex) +#endif + ) { printk(KERN_WARNING "%s: No versions for exported symbols.\n", mod->name); err = try_to_force_load(mod, "nocrc"); if (err) -- cgit v1.2.3 From 2f0f2a334bc38b61a9afca951185cd3844ee709d Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Tue, 22 Jul 2008 19:24:27 -0500 Subject: module: turn longs into ints for module sizes This shrinks module.o and each *.ko file. And finally, structure members which hold length of module code (four such members there) and count of symbols are converted from longs to ints. We cannot possibly have a module where 32 bits won't be enough to hold such counts. For one, module loading checks module size for sanity before loading, so such insanely big module will fail that test first. Signed-off-by: Denys Vlasenko Signed-off-by: Rusty Russell --- include/linux/module.h | 6 +++--- kernel/module.c | 4 ++-- 2 files changed, 5 insertions(+), 5 deletions(-) (limited to 'include/linux/module.h') diff --git a/include/linux/module.h b/include/linux/module.h index a860a2c1f379..fce15ebd0e1c 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -288,10 +288,10 @@ struct module void *module_core; /* Here are the sizes of the init and core sections */ - unsigned long init_size, core_size; + unsigned int init_size, core_size; /* The size of the executable code in each section. */ - unsigned long init_text_size, core_text_size; + unsigned int init_text_size, core_text_size; /* The handle returned from unwind_add_table. */ void *unwind_info; @@ -311,7 +311,7 @@ struct module #ifdef CONFIG_KALLSYMS /* We keep the symbol and string tables for kallsyms. */ Elf_Sym *symtab; - unsigned long num_symtab; + unsigned int num_symtab; char *strtab; /* Section attributes */ diff --git a/kernel/module.c b/kernel/module.c index ea9580521eb1..5c7eb0695b3c 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1567,7 +1567,7 @@ static int simplify_symbols(Elf_Shdr *sechdrs, } /* Update size with this section: return offset. */ -static long get_offset(unsigned long *size, Elf_Shdr *sechdr) +static long get_offset(unsigned int *size, Elf_Shdr *sechdr) { long ret; @@ -2562,7 +2562,7 @@ static int m_show(struct seq_file *m, void *p) struct module *mod = list_entry(p, struct module, list); char buf[8]; - seq_printf(m, "%s %lu", + seq_printf(m, "%s %u", mod->name, mod->init_size + mod->core_size); print_unload_info(m, mod); -- cgit v1.2.3