#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/err.h>
-#include <linux/jump_label.h>
+#include <linux/static_key.h>
#ifdef HAVE_JUMP_LABEL
mutex_unlock(&jump_label_mutex);
}
-bool jump_label_enabled(struct jump_label_key *key)
-{
- return !!atomic_read(&key->enabled);
-}
-
static int jump_label_cmp(const void *a, const void *b)
{
const struct jump_entry *jea = a;
sort(start, size, sizeof(struct jump_entry), jump_label_cmp, NULL);
}
-static void jump_label_update(struct jump_label_key *key, int enable);
+static void jump_label_update(struct static_key *key, int enable);
-void jump_label_inc(struct jump_label_key *key)
+void static_key_slow_inc(struct static_key *key)
{
if (atomic_inc_not_zero(&key->enabled))
return;
jump_label_lock();
- if (atomic_read(&key->enabled) == 0)
- jump_label_update(key, JUMP_LABEL_ENABLE);
+ if (atomic_read(&key->enabled) == 0) {
+ if (!jump_label_get_branch_default(key))
+ jump_label_update(key, JUMP_LABEL_ENABLE);
+ else
+ jump_label_update(key, JUMP_LABEL_DISABLE);
+ }
atomic_inc(&key->enabled);
jump_label_unlock();
}
-EXPORT_SYMBOL_GPL(jump_label_inc);
+EXPORT_SYMBOL_GPL(static_key_slow_inc);
-void jump_label_dec(struct jump_label_key *key)
+static void __static_key_slow_dec(struct static_key *key,
+ unsigned long rate_limit, struct delayed_work *work)
{
- if (!atomic_dec_and_mutex_lock(&key->enabled, &jump_label_mutex))
+ if (!atomic_dec_and_mutex_lock(&key->enabled, &jump_label_mutex)) {
+ WARN(atomic_read(&key->enabled) < 0,
+ "jump label: negative count!\n");
return;
+ }
- jump_label_update(key, JUMP_LABEL_DISABLE);
+ if (rate_limit) {
+ atomic_inc(&key->enabled);
+ schedule_delayed_work(work, rate_limit);
+ } else {
+ if (!jump_label_get_branch_default(key))
+ jump_label_update(key, JUMP_LABEL_DISABLE);
+ else
+ jump_label_update(key, JUMP_LABEL_ENABLE);
+ }
jump_label_unlock();
}
-EXPORT_SYMBOL_GPL(jump_label_dec);
+
+static void jump_label_update_timeout(struct work_struct *work)
+{
+ struct static_key_deferred *key =
+ container_of(work, struct static_key_deferred, work.work);
+ __static_key_slow_dec(&key->key, 0, NULL);
+}
+
+void static_key_slow_dec(struct static_key *key)
+{
+ __static_key_slow_dec(key, 0, NULL);
+}
+EXPORT_SYMBOL_GPL(static_key_slow_dec);
+
+void static_key_slow_dec_deferred(struct static_key_deferred *key)
+{
+ __static_key_slow_dec(&key->key, key->timeout, &key->work);
+}
+EXPORT_SYMBOL_GPL(static_key_slow_dec_deferred);
+
+void jump_label_rate_limit(struct static_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)
{
* 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);
}
-static void __jump_label_update(struct jump_label_key *key,
+static void __jump_label_update(struct static_key *key,
struct jump_entry *entry,
struct jump_entry *stop, int enable)
{
}
}
+static enum jump_label_type jump_label_type(struct static_key *key)
+{
+ bool true_branch = jump_label_get_branch_default(key);
+ bool state = static_key_enabled(key);
+
+ if ((!true_branch && state) || (true_branch && !state))
+ return JUMP_LABEL_ENABLE;
+
+ return JUMP_LABEL_DISABLE;
+}
+
void __init jump_label_init(void)
{
struct jump_entry *iter_start = __start___jump_table;
struct jump_entry *iter_stop = __stop___jump_table;
- struct jump_label_key *key = NULL;
+ struct static_key *key = NULL;
struct jump_entry *iter;
jump_label_lock();
jump_label_sort_entries(iter_start, iter_stop);
for (iter = iter_start; iter < iter_stop; iter++) {
- struct jump_label_key *iterk;
+ struct static_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);
+ iterk = (struct static_key *)(unsigned long)iter->key;
+ arch_jump_label_transform_static(iter, jump_label_type(iterk));
if (iterk == key)
continue;
key = iterk;
- key->entries = iter;
+ /*
+ * Set key->entries to iter, but preserve JUMP_LABEL_TRUE_BRANCH.
+ */
+ *((unsigned long *)&key->entries) += (unsigned long)iter;
#ifdef CONFIG_MODULES
key->next = NULL;
#endif
#ifdef CONFIG_MODULES
-struct jump_label_mod {
- struct jump_label_mod *next;
+struct static_key_mod {
+ struct static_key_mod *next;
struct jump_entry *entries;
struct module *mod;
};
start, end);
}
-static void __jump_label_mod_update(struct jump_label_key *key, int enable)
+static void __jump_label_mod_update(struct static_key *key, int enable)
{
- struct jump_label_mod *mod = key->next;
+ struct static_key_mod *mod = key->next;
while (mod) {
struct module *m = mod->mod;
if (iter_start == iter_stop)
return;
- for (iter = iter_start; iter < iter_stop; iter++)
+ for (iter = iter_start; iter < iter_stop; iter++) {
arch_jump_label_transform_static(iter, JUMP_LABEL_DISABLE);
+ }
}
static int jump_label_add_module(struct module *mod)
struct jump_entry *iter_start = mod->jump_entries;
struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
struct jump_entry *iter;
- struct jump_label_key *key = NULL;
- struct jump_label_mod *jlm;
+ struct static_key *key = NULL;
+ struct static_key_mod *jlm;
/* if the module doesn't have jump label entries, just return */
if (iter_start == iter_stop)
jump_label_sort_entries(iter_start, iter_stop);
for (iter = iter_start; iter < iter_stop; iter++) {
- if (iter->key == (jump_label_t)(unsigned long)key)
- continue;
+ struct static_key *iterk;
- key = (struct jump_label_key *)(unsigned long)iter->key;
+ iterk = (struct static_key *)(unsigned long)iter->key;
+ if (iterk == key)
+ continue;
+ key = iterk;
if (__module_address(iter->key) == mod) {
- atomic_set(&key->enabled, 0);
- key->entries = iter;
+ /*
+ * Set key->entries to iter, but preserve JUMP_LABEL_TRUE_BRANCH.
+ */
+ *((unsigned long *)&key->entries) += (unsigned long)iter;
key->next = NULL;
continue;
}
-
- jlm = kzalloc(sizeof(struct jump_label_mod), GFP_KERNEL);
+ jlm = kzalloc(sizeof(struct static_key_mod), GFP_KERNEL);
if (!jlm)
return -ENOMEM;
-
jlm->mod = mod;
jlm->entries = iter;
jlm->next = key->next;
key->next = jlm;
- if (jump_label_enabled(key))
- __jump_label_update(key, iter, iter_stop,
- JUMP_LABEL_ENABLE);
+ if (jump_label_type(key) == JUMP_LABEL_ENABLE)
+ __jump_label_update(key, iter, iter_stop, JUMP_LABEL_ENABLE);
}
return 0;
struct jump_entry *iter_start = mod->jump_entries;
struct jump_entry *iter_stop = iter_start + mod->num_jump_entries;
struct jump_entry *iter;
- struct jump_label_key *key = NULL;
- struct jump_label_mod *jlm, **prev;
+ struct static_key *key = NULL;
+ struct static_key_mod *jlm, **prev;
for (iter = iter_start; iter < iter_stop; iter++) {
if (iter->key == (jump_label_t)(unsigned long)key)
continue;
- key = (struct jump_label_key *)(unsigned long)iter->key;
+ key = (struct static_key *)(unsigned long)iter->key;
if (__module_address(iter->key) == mod)
continue;
return ret;
}
-static void jump_label_update(struct jump_label_key *key, int enable)
+static void jump_label_update(struct static_key *key, int enable)
{
- struct jump_entry *entry = key->entries, *stop = __stop___jump_table;
+ struct jump_entry *stop = __stop___jump_table;
+ struct jump_entry *entry = jump_label_get_entries(key);
#ifdef CONFIG_MODULES
- struct module *mod = __module_address((jump_label_t)key);
+ struct module *mod = __module_address((unsigned long)key);
__jump_label_mod_update(key, enable);
projects / linux-flexiantxendom0-3.2.10.git / blobdiff