From 75e12ed65312a56401f3b286ac7e12994301371c Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Tue, 6 Sep 2016 19:04:43 +0200 Subject: [PATCH] lib/irq_poll: Convert to hotplug state machine Install the callbacks via the state machine. Signed-off-by: Sebastian Andrzej Siewior Cc: Peter Zijlstra Cc: Jens Axboe Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160906170457.32393-8-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner --- include/linux/cpuhotplug.h | 1 + lib/irq_poll.c | 26 +++++++++----------------- 2 files changed, 10 insertions(+), 17 deletions(-) diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 8dec2a236af3..2ca7b34871e0 100644 --- 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 836f7db4e548..2be55692aa43 100644 --- 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);