diff options
| -rw-r--r-- | include/linux/module.h | 11 | ||||
| -rw-r--r-- | include/linux/percpu.h | 7 | ||||
| -rw-r--r-- | kernel/lockdep.c | 21 | ||||
| -rw-r--r-- | kernel/module.c | 104 | ||||
| -rw-r--r-- | mm/percpu.c | 26 |
5 files changed, 121 insertions, 48 deletions
diff --git a/include/linux/module.h b/include/linux/module.h index 5e869ffd34a..8bd399a0034 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -330,8 +330,11 @@ struct module struct module_notes_attrs *notes_attrs; #endif +#ifdef CONFIG_SMP /* Per-cpu data. */ - void *percpu; + void __percpu *percpu; + unsigned int percpu_size; +#endif /* The command line arguments (may be mangled). People like keeping pointers to this stuff */ @@ -392,6 +395,7 @@ static inline int module_is_live(struct module *mod) struct module *__module_text_address(unsigned long addr); struct module *__module_address(unsigned long addr); bool is_module_address(unsigned long addr); +bool is_module_percpu_address(unsigned long addr); bool is_module_text_address(unsigned long addr); static inline int within_module_core(unsigned long addr, struct module *mod) @@ -563,6 +567,11 @@ static inline bool is_module_address(unsigned long addr) return false; } +static inline bool is_module_percpu_address(unsigned long addr) +{ + return false; +} + static inline bool is_module_text_address(unsigned long addr) { return false; diff --git a/include/linux/percpu.h b/include/linux/percpu.h index a93e5bfdccb..11d5f834b54 100644 --- a/include/linux/percpu.h +++ b/include/linux/percpu.h @@ -137,6 +137,7 @@ extern int __init pcpu_page_first_chunk(size_t reserved_size, extern void __percpu *__alloc_reserved_percpu(size_t size, size_t align); extern void __percpu *__alloc_percpu(size_t size, size_t align); extern void free_percpu(void __percpu *__pdata); +extern bool is_kernel_percpu_address(unsigned long addr); extern phys_addr_t per_cpu_ptr_to_phys(void *addr); #ifndef CONFIG_HAVE_SETUP_PER_CPU_AREA @@ -163,6 +164,12 @@ static inline void free_percpu(void __percpu *p) kfree(p); } +/* can't distinguish from other static vars, always false */ +static inline bool is_kernel_percpu_address(unsigned long addr) +{ + return false; +} + static inline phys_addr_t per_cpu_ptr_to_phys(void *addr) { return __pa(addr); diff --git a/kernel/lockdep.c b/kernel/lockdep.c index c927a549db2..9bbb9c841e4 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -582,9 +582,6 @@ static int static_obj(void *obj) unsigned long start = (unsigned long) &_stext, end = (unsigned long) &_end, addr = (unsigned long) obj; -#ifdef CONFIG_SMP - int i; -#endif /* * static variable? @@ -595,24 +592,16 @@ static int static_obj(void *obj) if (arch_is_kernel_data(addr)) return 1; -#ifdef CONFIG_SMP /* - * percpu var? + * in-kernel percpu var? */ - for_each_possible_cpu(i) { - start = (unsigned long) &__per_cpu_start + per_cpu_offset(i); - end = (unsigned long) &__per_cpu_start + PERCPU_ENOUGH_ROOM - + per_cpu_offset(i); - - if ((addr >= start) && (addr < end)) - return 1; - } -#endif + if (is_kernel_percpu_address(addr)) + return 1; /* - * module var? + * module static or percpu var? */ - return is_module_address(addr); + return is_module_address(addr) || is_module_percpu_address(addr); } /* diff --git a/kernel/module.c b/kernel/module.c index c968d3606dc..9f8d23d8b3a 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -370,27 +370,33 @@ EXPORT_SYMBOL_GPL(find_module); #ifdef CONFIG_SMP -static void *percpu_modalloc(unsigned long size, unsigned long align, - const char *name) +static inline void __percpu *mod_percpu(struct module *mod) { - void *ptr; + return mod->percpu; +} +static int percpu_modalloc(struct module *mod, + unsigned long size, unsigned long align) +{ if (align > PAGE_SIZE) { printk(KERN_WARNING "%s: per-cpu alignment %li > %li\n", - name, align, PAGE_SIZE); + mod->name, align, PAGE_SIZE); align = PAGE_SIZE; } - ptr = __alloc_reserved_percpu(size, align); - if (!ptr) + mod->percpu = __alloc_reserved_percpu(size, align); + if (!mod->percpu) { printk(KERN_WARNING "Could not allocate %lu bytes percpu data\n", size); - return ptr; + return -ENOMEM; + } + mod->percpu_size = size; + return 0; } -static void percpu_modfree(void *freeme) +static void percpu_modfree(struct module *mod) { - free_percpu(freeme); + free_percpu(mod->percpu); } static unsigned int find_pcpusec(Elf_Ehdr *hdr, @@ -400,24 +406,62 @@ static unsigned int find_pcpusec(Elf_Ehdr *hdr, return find_sec(hdr, sechdrs, secstrings, ".data.percpu"); } -static void percpu_modcopy(void *pcpudest, const void *from, unsigned long size) +static void percpu_modcopy(struct module *mod, + const void *from, unsigned long size) { int cpu; for_each_possible_cpu(cpu) - memcpy(pcpudest + per_cpu_offset(cpu), from, size); + memcpy(per_cpu_ptr(mod->percpu, cpu), from, size); +} + +/** + * is_module_percpu_address - test whether address is from module static percpu + * @addr: address to test + * + * Test whether @addr belongs to module static percpu area. + * + * RETURNS: + * %true if @addr is from module static percpu area + */ +bool is_module_percpu_address(unsigned long addr) +{ + struct module *mod; + unsigned int cpu; + + preempt_disable(); + + list_for_each_entry_rcu(mod, &modules, list) { + if (!mod->percpu_size) + continue; + for_each_possible_cpu(cpu) { + void *start = per_cpu_ptr(mod->percpu, cpu); + + if ((void *)addr >= start && + (void *)addr < start + mod->percpu_size) { + preempt_enable(); + return true; + } + } + } + + preempt_enable(); + return false; } #else /* ... !CONFIG_SMP */ -static inline void *percpu_modalloc(unsigned long size, unsigned long align, - const char *name) +static inline void __percpu *mod_percpu(struct module *mod) { return NULL; } -static inline void percpu_modfree(void *pcpuptr) +static inline int percpu_modalloc(struct module *mod, + unsigned long size, unsigned long align) +{ + return -ENOMEM; +} +static inline void percpu_modfree(struct module *mod) { - BUG(); } static inline unsigned int find_pcpusec(Elf_Ehdr *hdr, Elf_Shdr *sechdrs, @@ -425,12 +469,16 @@ static inline unsigned int find_pcpusec(Elf_Ehdr *hdr, { return 0; } -static inline void percpu_modcopy(void *pcpudst, const void *src, - unsigned long size) +static inline void percpu_modcopy(struct module *mod, + const void *from, unsigned long size) { /* pcpusec should be 0, and size of that section should be 0. */ BUG_ON(size != 0); } +bool is_module_percpu_address(unsigned long addr) +{ + return false; +} #endif /* CONFIG_SMP */ @@ -1400,8 +1448,7 @@ static void free_module(struct module *mod) /* This may be NULL, but that's OK */ module_free(mod, mod->module_init); kfree(mod->args); - if (mod->percpu) - percpu_modfree(mod->percpu); + percpu_modfree(mod); #if defined(CONFIG_MODULE_UNLOAD) if (mod->refptr) free_percpu(mod->refptr); @@ -1520,7 +1567,7 @@ static int simplify_symbols(Elf_Shdr *sechdrs, default: /* Divert to percpu allocation if a percpu var. */ if (sym[i].st_shndx == pcpuindex) - secbase = (unsigned long)mod->percpu; + secbase = (unsigned long)mod_percpu(mod); else secbase = sechdrs[sym[i].st_shndx].sh_addr; sym[i].st_value += secbase; @@ -1954,7 +2001,7 @@ static noinline struct module *load_module(void __user *umod, unsigned int modindex, versindex, infoindex, pcpuindex; struct module *mod; long err = 0; - void *percpu = NULL, *ptr = NULL; /* Stops spurious gcc warning */ + void *ptr = NULL; /* Stops spurious gcc warning */ unsigned long symoffs, stroffs, *strmap; mm_segment_t old_fs; @@ -2094,15 +2141,11 @@ static noinline struct module *load_module(void __user *umod, if (pcpuindex) { /* We have a special allocation for this section. */ - percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size, - sechdrs[pcpuindex].sh_addralign, - mod->name); - if (!percpu) { - err = -ENOMEM; + err = percpu_modalloc(mod, sechdrs[pcpuindex].sh_size, + sechdrs[pcpuindex].sh_addralign); + if (err) goto free_mod; - } sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC; - mod->percpu = percpu; } /* Determine total sizes, and put offsets in sh_entsize. For now @@ -2317,7 +2360,7 @@ static noinline struct module *load_module(void __user *umod, sort_extable(mod->extable, mod->extable + mod->num_exentries); /* Finally, copy percpu area over. */ - percpu_modcopy(mod->percpu, (void *)sechdrs[pcpuindex].sh_addr, + percpu_modcopy(mod, (void *)sechdrs[pcpuindex].sh_addr, sechdrs[pcpuindex].sh_size); add_kallsyms(mod, sechdrs, hdr->e_shnum, symindex, strindex, @@ -2409,8 +2452,7 @@ static noinline struct module *load_module(void __user *umod, module_free(mod, mod->module_core); /* mod will be freed with core. Don't access it beyond this line! */ free_percpu: - if (percpu) - percpu_modfree(percpu); + percpu_modfree(mod); free_mod: kfree(args); kfree(strmap); diff --git a/mm/percpu.c b/mm/percpu.c index 768419d44ad..6e09741ddc6 100644 --- a/mm/percpu.c +++ b/mm/percpu.c @@ -1304,6 +1304,32 @@ void free_percpu(void __percpu *ptr) EXPORT_SYMBOL_GPL(free_percpu); /** + * is_kernel_percpu_address - test whether address is from static percpu area + * @addr: address to test + * + * Test whether @addr belongs to in-kernel static percpu area. Module + * static percpu areas are not considered. For those, use + * is_module_percpu_address(). + * + * RETURNS: + * %true if @addr is from in-kernel static percpu area, %false otherwise. + */ +bool is_kernel_percpu_address(unsigned long addr) +{ + const size_t static_size = __per_cpu_end - __per_cpu_start; + void __percpu *base = __addr_to_pcpu_ptr(pcpu_base_addr); + unsigned int cpu; + + for_each_possible_cpu(cpu) { + void *start = per_cpu_ptr(base, cpu); + + if ((void *)addr >= start && (void *)addr < start + static_size) + return true; + } + return false; +} + +/** * per_cpu_ptr_to_phys - convert translated percpu address to physical address * @addr: the address to be converted to physical address * |