diff options
| -rw-r--r-- | arch/s390/kernel/jump_label.c | 51 | ||||
| -rw-r--r-- | arch/sparc/kernel/jump_label.c | 8 | ||||
| -rw-r--r-- | arch/x86/kernel/jump_label.c | 20 | ||||
| -rw-r--r-- | include/linux/jump_label.h | 23 | ||||
| -rw-r--r-- | init/main.c | 3 | ||||
| -rw-r--r-- | kernel/jump_label.c | 37 |
6 files changed, 83 insertions, 59 deletions
diff --git a/arch/s390/kernel/jump_label.c b/arch/s390/kernel/jump_label.c index 44cc06bedf77..b987ab2c1541 100644 --- a/arch/s390/kernel/jump_label.c +++ b/arch/s390/kernel/jump_label.c @@ -18,26 +18,15 @@ struct insn { } __packed; struct insn_args { - unsigned long *target; - struct insn *insn; - ssize_t size; + struct jump_entry *entry; + enum jump_label_type type; }; -static int __arch_jump_label_transform(void *data) +static void __jump_label_transform(struct jump_entry *entry, + enum jump_label_type type) { - struct insn_args *args = data; - int rc; - - rc = probe_kernel_write(args->target, args->insn, args->size); - WARN_ON_ONCE(rc < 0); - return 0; -} - -void arch_jump_label_transform(struct jump_entry *entry, - enum jump_label_type type) -{ - struct insn_args args; struct insn insn; + int rc; if (type == JUMP_LABEL_ENABLE) { /* brcl 15,offset */ @@ -49,11 +38,33 @@ void arch_jump_label_transform(struct jump_entry *entry, insn.offset = 0; } - args.target = (void *) entry->code; - args.insn = &insn; - args.size = JUMP_LABEL_NOP_SIZE; + rc = probe_kernel_write((void *)entry->code, &insn, JUMP_LABEL_NOP_SIZE); + WARN_ON_ONCE(rc < 0); +} - stop_machine(__arch_jump_label_transform, &args, NULL); +static int __sm_arch_jump_label_transform(void *data) +{ + struct insn_args *args = data; + + __jump_label_transform(args->entry, args->type); + return 0; +} + +void arch_jump_label_transform(struct jump_entry *entry, + enum jump_label_type type) +{ + struct insn_args args; + + args.entry = entry; + args.type = type; + + stop_machine(__sm_arch_jump_label_transform, &args, NULL); +} + +void arch_jump_label_transform_static(struct jump_entry *entry, + enum jump_label_type type) +{ + __jump_label_transform(entry, type); } #endif diff --git a/arch/sparc/kernel/jump_label.c b/arch/sparc/kernel/jump_label.c index ea2dafc93d78..971fd435a281 100644 --- a/arch/sparc/kernel/jump_label.c +++ b/arch/sparc/kernel/jump_label.c @@ -36,12 +36,4 @@ void arch_jump_label_transform(struct jump_entry *entry, put_online_cpus(); } -void arch_jump_label_text_poke_early(jump_label_t addr) -{ - u32 *insn_p = (u32 *) (unsigned long) addr; - - *insn_p = 0x01000000; - flushi(insn_p); -} - #endif diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c index cacdd46d184d..ea9d5f2f13ef 100644 --- a/arch/x86/kernel/jump_label.c +++ b/arch/x86/kernel/jump_label.c @@ -24,8 +24,9 @@ union jump_code_union { } __attribute__((packed)); }; -void arch_jump_label_transform(struct jump_entry *entry, - enum jump_label_type type) +static void __jump_label_transform(struct jump_entry *entry, + enum jump_label_type type, + void *(*poker)(void *, const void *, size_t)) { union jump_code_union code; @@ -35,17 +36,24 @@ void arch_jump_label_transform(struct jump_entry *entry, (entry->code + JUMP_LABEL_NOP_SIZE); } else memcpy(&code, ideal_nops[NOP_ATOMIC5], JUMP_LABEL_NOP_SIZE); + + (*poker)((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE); +} + +void arch_jump_label_transform(struct jump_entry *entry, + enum jump_label_type type) +{ get_online_cpus(); mutex_lock(&text_mutex); - text_poke_smp((void *)entry->code, &code, JUMP_LABEL_NOP_SIZE); + __jump_label_transform(entry, type, text_poke_smp); mutex_unlock(&text_mutex); put_online_cpus(); } -void __init_or_module arch_jump_label_text_poke_early(jump_label_t addr) +void arch_jump_label_transform_static(struct jump_entry *entry, + enum jump_label_type type) { - text_poke_early((void *)addr, ideal_nops[NOP_ATOMIC5], - JUMP_LABEL_NOP_SIZE); + __jump_label_transform(entry, type, text_poke_early); } #endif diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h index 66f23dc5e76a..388b0d425b50 100644 --- a/include/linux/jump_label.h +++ b/include/linux/jump_label.h @@ -16,7 +16,7 @@ struct jump_label_key { # include <asm/jump_label.h> # define HAVE_JUMP_LABEL -#endif +#endif /* CC_HAVE_ASM_GOTO && CONFIG_JUMP_LABEL */ enum jump_label_type { JUMP_LABEL_DISABLE = 0, @@ -28,9 +28,9 @@ struct module; #ifdef HAVE_JUMP_LABEL #ifdef CONFIG_MODULES -#define JUMP_LABEL_INIT {{ 0 }, NULL, NULL} +#define JUMP_LABEL_INIT {ATOMIC_INIT(0), NULL, NULL} #else -#define JUMP_LABEL_INIT {{ 0 }, NULL} +#define JUMP_LABEL_INIT {ATOMIC_INIT(0), NULL} #endif static __always_inline bool static_branch(struct jump_label_key *key) @@ -41,18 +41,20 @@ static __always_inline bool static_branch(struct jump_label_key *key) extern struct jump_entry __start___jump_table[]; extern struct jump_entry __stop___jump_table[]; +extern void jump_label_init(void); extern void jump_label_lock(void); extern void jump_label_unlock(void); extern void arch_jump_label_transform(struct jump_entry *entry, - enum jump_label_type type); -extern void arch_jump_label_text_poke_early(jump_label_t addr); + enum jump_label_type type); +extern void arch_jump_label_transform_static(struct jump_entry *entry, + enum jump_label_type type); extern int jump_label_text_reserved(void *start, void *end); extern void jump_label_inc(struct jump_label_key *key); extern void jump_label_dec(struct jump_label_key *key); extern bool jump_label_enabled(struct jump_label_key *key); extern void jump_label_apply_nops(struct module *mod); -#else +#else /* !HAVE_JUMP_LABEL */ #include <linux/atomic.h> @@ -62,6 +64,10 @@ struct jump_label_key { atomic_t enabled; }; +static __always_inline void jump_label_init(void) +{ +} + static __always_inline bool static_branch(struct jump_label_key *key) { if (unlikely(atomic_read(&key->enabled))) @@ -96,7 +102,6 @@ static inline int jump_label_apply_nops(struct module *mod) { return 0; } +#endif /* HAVE_JUMP_LABEL */ -#endif - -#endif +#endif /* _LINUX_JUMP_LABEL_H */ diff --git a/init/main.c b/init/main.c index 63f5f6f8dc3b..217ed23e9487 100644 --- a/init/main.c +++ b/init/main.c @@ -512,6 +512,9 @@ asmlinkage void __init start_kernel(void) parse_args("Booting kernel", static_command_line, __start___param, __stop___param - __start___param, &unknown_bootoption); + + jump_label_init(); + /* * These use large bootmem allocations and must precede * kmem_cache_init() diff --git a/kernel/jump_label.c b/kernel/jump_label.c index a8ce45097f3d..bbdfe2a462a0 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -104,6 +104,18 @@ static int __jump_label_text_reserved(struct jump_entry *iter_start, return 0; } +/* + * Update code which is definitely not currently executing. + * Architectures which need heavyweight synchronization to modify + * running code can override this to make the non-live update case + * cheaper. + */ +void __weak arch_jump_label_transform_static(struct jump_entry *entry, + enum jump_label_type type) +{ + arch_jump_label_transform(entry, type); +} + static void __jump_label_update(struct jump_label_key *key, struct jump_entry *entry, struct jump_entry *stop, int enable) @@ -121,14 +133,7 @@ static void __jump_label_update(struct jump_label_key *key, } } -/* - * Not all archs need this. - */ -void __weak arch_jump_label_text_poke_early(jump_label_t addr) -{ -} - -static __init int jump_label_init(void) +void __init jump_label_init(void) { struct jump_entry *iter_start = __start___jump_table; struct jump_entry *iter_stop = __stop___jump_table; @@ -139,22 +144,22 @@ static __init int jump_label_init(void) jump_label_sort_entries(iter_start, iter_stop); for (iter = iter_start; iter < iter_stop; iter++) { - arch_jump_label_text_poke_early(iter->code); - if (iter->key == (jump_label_t)(unsigned long)key) + struct jump_label_key *iterk; + + iterk = (struct jump_label_key *)(unsigned long)iter->key; + arch_jump_label_transform_static(iter, jump_label_enabled(iterk) ? + JUMP_LABEL_ENABLE : JUMP_LABEL_DISABLE); + if (iterk == key) continue; - key = (struct jump_label_key *)(unsigned long)iter->key; - atomic_set(&key->enabled, 0); + key = iterk; key->entries = iter; #ifdef CONFIG_MODULES key->next = NULL; #endif } jump_label_unlock(); - - return 0; } -early_initcall(jump_label_init); #ifdef CONFIG_MODULES @@ -212,7 +217,7 @@ void jump_label_apply_nops(struct module *mod) return; for (iter = iter_start; iter < iter_stop; iter++) - arch_jump_label_text_poke_early(iter->code); + arch_jump_label_transform_static(iter, JUMP_LABEL_DISABLE); } static int jump_label_add_module(struct module *mod) |