lib/irq_poll: Convert to hotplug state machine

Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160906170457.32393-8-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 8dec2a236af3c05e9bac8fbebf516ae110de2383..2ca7b34871e0cc0c661bf793f4a99dfb918c43e6 100644 (file)
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -22,6 +22,7 @@ enum cpuhp_state {
        CPUHP_CPUIDLE_DEAD,
        CPUHP_ARM64_FPSIMD_DEAD,
        CPUHP_ARM_OMAP_WAKE_DEAD,
+       CPUHP_IRQ_POLL_DEAD,
        CPUHP_WORKQUEUE_PREP,
        CPUHP_POWER_NUMA_PREPARE,
        CPUHP_HRTIMERS_PREPARE,

diff --git a/lib/irq_poll.c b/lib/irq_poll.c
index 836f7db4e548e8142b09f8b6d147d926d42a3f99..2be55692aa43fc5f9d4f9fbe4d337e38fe359b45 100644 (file)
--- a/lib/irq_poll.c
+++ b/lib/irq_poll.c
@@ -184,30 +184,21 @@ void irq_poll_init(struct irq_poll *iop, int weight, irq_poll_fn *poll_fn)
 }
 EXPORT_SYMBOL(irq_poll_init);
 
-static int irq_poll_cpu_notify(struct notifier_block *self,
-                                unsigned long action, void *hcpu)
+static int irq_poll_cpu_dead(unsigned int cpu)
 {
        /*
         * If a CPU goes away, splice its entries to the current CPU
         * and trigger a run of the softirq
         */
-       if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
-               int cpu = (unsigned long) hcpu;
-
-               local_irq_disable();
-               list_splice_init(&per_cpu(blk_cpu_iopoll, cpu),
-                                this_cpu_ptr(&blk_cpu_iopoll));
-               __raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
-               local_irq_enable();
-       }
+       local_irq_disable();
+       list_splice_init(&per_cpu(blk_cpu_iopoll, cpu),
+                        this_cpu_ptr(&blk_cpu_iopoll));
+       __raise_softirq_irqoff(IRQ_POLL_SOFTIRQ);
+       local_irq_enable();
 
-       return NOTIFY_OK;
+       return 0;
 }
 
-static struct notifier_block irq_poll_cpu_notifier = {
-       .notifier_call  = irq_poll_cpu_notify,
-};
-
 static __init int irq_poll_setup(void)
 {
        int i;
@@ -216,7 +207,8 @@ static __init int irq_poll_setup(void)
                INIT_LIST_HEAD(&per_cpu(blk_cpu_iopoll, i));
 
        open_softirq(IRQ_POLL_SOFTIRQ, irq_poll_softirq);
-       register_hotcpu_notifier(&irq_poll_cpu_notifier);
+       cpuhp_setup_state_nocalls(CPUHP_IRQ_POLL_DEAD, "irq_poll:dead", NULL,
+                                 irq_poll_cpu_dead);
        return 0;
 }
 subsys_initcall(irq_poll_setup);