s390/irq: use hlists for external interrupt handler array
Use hlists for the hashed array of external interrupt handlers.
Reduces the size of the array by 50% (2KB).
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index b34ba0e..4ecf017 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -196,13 +196,13 @@
* ext_int_hash[index] is the list head for all external interrupts that hash
* to this index.
*/
-static struct list_head ext_int_hash[256];
+static struct hlist_head ext_int_hash[256];
struct ext_int_info {
ext_int_handler_t handler;
- u16 code;
- struct list_head entry;
+ struct hlist_node entry;
struct rcu_head rcu;
+ u16 code;
};
/* ext_int_hash_lock protects the handler lists for external interrupts */
@@ -227,7 +227,7 @@
index = ext_hash(code);
spin_lock_irqsave(&ext_int_hash_lock, flags);
- list_add_rcu(&p->entry, &ext_int_hash[index]);
+ hlist_add_head_rcu(&p->entry, &ext_int_hash[index]);
spin_unlock_irqrestore(&ext_int_hash_lock, flags);
return 0;
}
@@ -240,9 +240,9 @@
int index = ext_hash(code);
spin_lock_irqsave(&ext_int_hash_lock, flags);
- list_for_each_entry_rcu(p, &ext_int_hash[index], entry) {
+ hlist_for_each_entry_rcu(p, &ext_int_hash[index], entry) {
if (p->code == code && p->handler == handler) {
- list_del_rcu(&p->entry);
+ hlist_del_rcu(&p->entry);
kfree_rcu(p, rcu);
}
}
@@ -264,12 +264,12 @@
index = ext_hash(ext_code.code);
rcu_read_lock();
- list_for_each_entry_rcu(p, &ext_int_hash[index], entry)
- if (likely(p->code == ext_code.code))
- p->handler(ext_code, regs->int_parm,
- regs->int_parm_long);
+ hlist_for_each_entry_rcu(p, &ext_int_hash[index], entry) {
+ if (unlikely(p->code != ext_code.code))
+ continue;
+ p->handler(ext_code, regs->int_parm, regs->int_parm_long);
+ }
rcu_read_unlock();
-
return IRQ_HANDLED;
}
@@ -283,7 +283,7 @@
int idx;
for (idx = 0; idx < ARRAY_SIZE(ext_int_hash); idx++)
- INIT_LIST_HEAD(&ext_int_hash[idx]);
+ INIT_HLIST_HEAD(&ext_int_hash[idx]);
irq_set_chip_and_handler(EXT_INTERRUPT,
&dummy_irq_chip, handle_percpu_irq);
