From 50ce749d0d107aaed8c2d702b987529f978a40f7 Mon Sep 17 00:00:00 2001 From: Heiko Carstens Date: Tue, 3 Sep 2013 14:12:07 +0200 Subject: [PATCH] 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 --- arch/s390/kernel/irq.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c index b34ba0ea96a9..4ecf017f697c 100644 --- a/arch/s390/kernel/irq.c +++ b/arch/s390/kernel/irq.c @@ -196,13 +196,13 @@ asmlinkage void do_softirq(void) * 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 @@ int register_external_interrupt(u16 code, ext_int_handler_t handler) 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 unregister_external_interrupt(u16 code, ext_int_handler_t handler) 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 @@ static irqreturn_t do_ext_interrupt(int irq, void *dummy) 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 @@ void __init init_ext_interrupts(void) 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);