[PATCH] ia64: don't call note_interrupt() for per-CPU irqs

The note_interrupt() code is racy for per-CPU irqs and causes severe
performance problems due to cache-line bouncing on large SMPs.  Just don't
call it for that case.

diff --git a/arch/ia64/kernel/irq.c b/arch/ia64/kernel/irq.c
index f337fbb51b9059749b013a319ba64d529e7f65a4..61b1c97eac85e49c825aa1ce23478f6e0d0beb5c 100644 (file)
--- a/arch/ia64/kernel/irq.c
+++ b/arch/ia64/kernel/irq.c
@@ -465,8 +465,6 @@ unsigned int do_IRQ(unsigned long irq, struct pt_regs *regs)
                desc->handler->ack(irq);
                action_ret = handle_IRQ_event(irq, regs, desc->action);
                desc->handler->end(irq);
-               if (!noirqdebug)
-                       note_interrupt(irq, desc, action_ret);
        } else {
                spin_lock(&desc->lock);
                desc->handler->ack(irq);