diff options
| -rw-r--r-- | include/linux/module.h | 25 | ||||
| -rw-r--r-- | kernel/module.c | 35 |
2 files changed, 41 insertions, 19 deletions
diff --git a/include/linux/module.h b/include/linux/module.h index 4f7ea12463d..f3b8329eb5b 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -219,11 +219,6 @@ void *__symbol_get_gpl(const char *symbol); #endif -struct module_ref -{ - local_t count; -} ____cacheline_aligned; - enum module_state { MODULE_STATE_LIVE, @@ -344,8 +339,11 @@ struct module /* Destruction function. */ void (*exit)(void); - /* Reference counts */ - struct module_ref ref[NR_CPUS]; +#ifdef CONFIG_SMP + char *refptr; +#else + local_t ref; +#endif #endif }; #ifndef MODULE_ARCH_INIT @@ -395,13 +393,22 @@ void __symbol_put(const char *symbol); #define symbol_put(x) __symbol_put(MODULE_SYMBOL_PREFIX #x) void symbol_put_addr(void *addr); +static inline local_t *__module_ref_addr(struct module *mod, int cpu) +{ +#ifdef CONFIG_SMP + return (local_t *) (mod->refptr + per_cpu_offset(cpu)); +#else + return &mod->ref; +#endif +} + /* Sometimes we know we already have a refcount, and it's easier not to handle the error case (which only happens with rmmod --wait). */ static inline void __module_get(struct module *module) { if (module) { BUG_ON(module_refcount(module) == 0); - local_inc(&module->ref[get_cpu()].count); + local_inc(__module_ref_addr(module, get_cpu())); put_cpu(); } } @@ -413,7 +420,7 @@ static inline int try_module_get(struct module *module) if (module) { unsigned int cpu = get_cpu(); if (likely(module_is_live(module))) - local_inc(&module->ref[cpu].count); + local_inc(__module_ref_addr(module, cpu)); else ret = 0; put_cpu(); diff --git a/kernel/module.c b/kernel/module.c index e8b51d41dd7..ba22484a987 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -573,13 +573,13 @@ static char last_unloaded_module[MODULE_NAME_LEN+1]; /* Init the unload section of the module. */ static void module_unload_init(struct module *mod) { - unsigned int i; + int cpu; INIT_LIST_HEAD(&mod->modules_which_use_me); - for (i = 0; i < NR_CPUS; i++) - local_set(&mod->ref[i].count, 0); + for_each_possible_cpu(cpu) + local_set(__module_ref_addr(mod, cpu), 0); /* Hold reference count during initialization. */ - local_set(&mod->ref[raw_smp_processor_id()].count, 1); + local_set(__module_ref_addr(mod, raw_smp_processor_id()), 1); /* Backwards compatibility macros put refcount during init. */ mod->waiter = current; } @@ -717,10 +717,11 @@ static int try_stop_module(struct module *mod, int flags, int *forced) unsigned int module_refcount(struct module *mod) { - unsigned int i, total = 0; + unsigned int total = 0; + int cpu; - for (i = 0; i < NR_CPUS; i++) - total += local_read(&mod->ref[i].count); + for_each_possible_cpu(cpu) + total += local_read(__module_ref_addr(mod, cpu)); return total; } EXPORT_SYMBOL(module_refcount); @@ -894,7 +895,7 @@ void module_put(struct module *module) { if (module) { unsigned int cpu = get_cpu(); - local_dec(&module->ref[cpu].count); + local_dec(__module_ref_addr(module, cpu)); /* Maybe they're waiting for us to drop reference? */ if (unlikely(!module_is_live(module))) wake_up_process(module->waiter); @@ -1464,7 +1465,10 @@ static void free_module(struct module *mod) kfree(mod->args); if (mod->percpu) percpu_modfree(mod->percpu); - +#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP) + if (mod->refptr) + percpu_modfree(mod->refptr); +#endif /* Free lock-classes: */ lockdep_free_key_range(mod->module_core, mod->core_size); @@ -2011,6 +2015,14 @@ static noinline struct module *load_module(void __user *umod, if (err < 0) goto free_mod; +#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP) + mod->refptr = percpu_modalloc(sizeof(local_t), __alignof__(local_t), + mod->name); + if (!mod->refptr) { + err = -ENOMEM; + goto free_mod; + } +#endif if (pcpuindex) { /* We have a special allocation for this section. */ percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size, @@ -2018,7 +2030,7 @@ static noinline struct module *load_module(void __user *umod, mod->name); if (!percpu) { err = -ENOMEM; - goto free_mod; + goto free_percpu; } sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC; mod->percpu = percpu; @@ -2282,6 +2294,9 @@ static noinline struct module *load_module(void __user *umod, free_percpu: if (percpu) percpu_modfree(percpu); +#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP) + percpu_modfree(mod->refptr); +#endif free_mod: kfree(args); free_hdr: |