diff options
Diffstat (limited to 'kernel/jump_label.c')
| -rw-r--r-- | kernel/jump_label.c | 52 |
1 files changed, 44 insertions, 8 deletions
diff --git a/kernel/jump_label.c b/kernel/jump_label.c index bbdfe2a462a0..30c3c7708132 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -66,20 +66,52 @@ void jump_label_inc(struct jump_label_key *key) return; jump_label_lock(); - if (atomic_add_return(1, &key->enabled) == 1) + if (atomic_read(&key->enabled) == 0) jump_label_update(key, JUMP_LABEL_ENABLE); + atomic_inc(&key->enabled); jump_label_unlock(); } -void jump_label_dec(struct jump_label_key *key) +static void __jump_label_dec(struct jump_label_key *key, + unsigned long rate_limit, struct delayed_work *work) { if (!atomic_dec_and_mutex_lock(&key->enabled, &jump_label_mutex)) return; - jump_label_update(key, JUMP_LABEL_DISABLE); + if (rate_limit) { + atomic_inc(&key->enabled); + schedule_delayed_work(work, rate_limit); + } else + jump_label_update(key, JUMP_LABEL_DISABLE); + jump_label_unlock(); } +static void jump_label_update_timeout(struct work_struct *work) +{ + struct jump_label_key_deferred *key = + container_of(work, struct jump_label_key_deferred, work.work); + __jump_label_dec(&key->key, 0, NULL); +} + +void jump_label_dec(struct jump_label_key *key) +{ + __jump_label_dec(key, 0, NULL); +} + +void jump_label_dec_deferred(struct jump_label_key_deferred *key) +{ + __jump_label_dec(&key->key, key->timeout, &key->work); +} + + +void jump_label_rate_limit(struct jump_label_key_deferred *key, + unsigned long rl) +{ + key->timeout = rl; + INIT_DELAYED_WORK(&key->work, jump_label_update_timeout); +} + static int addr_conflict(struct jump_entry *entry, void *start, void *end) { if (entry->code <= (unsigned long)end && @@ -110,7 +142,7 @@ static int __jump_label_text_reserved(struct jump_entry *iter_start, * running code can override this to make the non-live update case * cheaper. */ -void __weak arch_jump_label_transform_static(struct jump_entry *entry, +void __weak __init_or_module arch_jump_label_transform_static(struct jump_entry *entry, enum jump_label_type type) { arch_jump_label_transform(entry, type); @@ -216,8 +248,13 @@ void jump_label_apply_nops(struct module *mod) if (iter_start == iter_stop) return; - for (iter = iter_start; iter < iter_stop; iter++) - arch_jump_label_transform_static(iter, JUMP_LABEL_DISABLE); + for (iter = iter_start; iter < iter_stop; iter++) { + 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); + } } static int jump_label_add_module(struct module *mod) @@ -257,8 +294,7 @@ static int jump_label_add_module(struct module *mod) key->next = jlm; if (jump_label_enabled(key)) - __jump_label_update(key, iter, iter_stop, - JUMP_LABEL_ENABLE); + __jump_label_update(key, iter, iter_stop, JUMP_LABEL_ENABLE); } return 0; |
