diff options
Diffstat (limited to 'kernel/jump_label.c')
-rw-r--r-- | kernel/jump_label.c | 64 |
1 files changed, 54 insertions, 10 deletions
diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 0bfa10f4410c..df3008419a1d 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -37,12 +37,26 @@ static int jump_label_cmp(const void *a, const void *b) const struct jump_entry *jea = a; const struct jump_entry *jeb = b; + /* + * Entrires are sorted by key. + */ if (jump_entry_key(jea) < jump_entry_key(jeb)) return -1; if (jump_entry_key(jea) > jump_entry_key(jeb)) return 1; + /* + * In the batching mode, entries should also be sorted by the code + * inside the already sorted list of entries, enabling a bsearch in + * the vector. + */ + if (jump_entry_code(jea) < jump_entry_code(jeb)) + return -1; + + if (jump_entry_code(jea) > jump_entry_code(jeb)) + return 1; + return 0; } @@ -384,25 +398,55 @@ static enum jump_label_type jump_label_type(struct jump_entry *entry) return enabled ^ branch; } +static bool jump_label_can_update(struct jump_entry *entry, bool init) +{ + /* + * Cannot update code that was in an init text area. + */ + if (!init && jump_entry_is_init(entry)) + return false; + + if (!kernel_text_address(jump_entry_code(entry))) { + WARN_ONCE(1, "can't patch jump_label at %pS", (void *)jump_entry_code(entry)); + return false; + } + + return true; +} + +#ifndef HAVE_JUMP_LABEL_BATCH static void __jump_label_update(struct static_key *key, struct jump_entry *entry, struct jump_entry *stop, bool init) { for (; (entry < stop) && (jump_entry_key(entry) == key); entry++) { - /* - * An entry->code of 0 indicates an entry which has been - * disabled because it was in an init text area. - */ - if (init || !jump_entry_is_init(entry)) { - if (kernel_text_address(jump_entry_code(entry))) - arch_jump_label_transform(entry, jump_label_type(entry)); - else - WARN_ONCE(1, "can't patch jump_label at %pS", - (void *)jump_entry_code(entry)); + if (jump_label_can_update(entry, init)) + arch_jump_label_transform(entry, jump_label_type(entry)); + } +} +#else +static void __jump_label_update(struct static_key *key, + struct jump_entry *entry, + struct jump_entry *stop, + bool init) +{ + for (; (entry < stop) && (jump_entry_key(entry) == key); entry++) { + + if (!jump_label_can_update(entry, init)) + continue; + + if (!arch_jump_label_transform_queue(entry, jump_label_type(entry))) { + /* + * Queue is full: Apply the current queue and try again. + */ + arch_jump_label_transform_apply(); + BUG_ON(!arch_jump_label_transform_queue(entry, jump_label_type(entry))); } } + arch_jump_label_transform_apply(); } +#endif void __init jump_label_init(void) { |