From 148b9e2abea6f50e4620e4ac0683b4913c4364c0 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 13 Jul 2016 17:16:34 +0000 Subject: [PATCH] x86/apb_timer: Convert to hotplug state machine Install the callbacks via the state machine. There is no setup just one teardown callback. Remove the silly comment about the workqueue up dependency. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Anna-Maria Gleixner Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153335.625342983@linutronix.de Signed-off-by: Ingo Molnar --- arch/x86/kernel/apb_timer.c | 29 ++++++++++------------------- include/linux/cpuhotplug.h | 1 + 2 files changed, 11 insertions(+), 19 deletions(-) diff --git a/arch/x86/kernel/apb_timer.c b/arch/x86/kernel/apb_timer.c index cefacbad1531..456316f6c868 100644 --- a/arch/x86/kernel/apb_timer.c +++ b/arch/x86/kernel/apb_timer.c @@ -215,26 +215,18 @@ void apbt_setup_secondary_clock(void) * cpu timers during the offline process due to the ordering of notification. * the extra interrupt is harmless. */ -static int apbt_cpuhp_notify(struct notifier_block *n, - unsigned long action, void *hcpu) +static int apbt_cpu_dead(unsigned int cpu) { - unsigned long cpu = (unsigned long)hcpu; struct apbt_dev *adev = &per_cpu(cpu_apbt_dev, cpu); - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_DEAD: - dw_apb_clockevent_pause(adev->timer); - if (system_state == SYSTEM_RUNNING) { - pr_debug("skipping APBT CPU %lu offline\n", cpu); - } else { - pr_debug("APBT clockevent for cpu %lu offline\n", cpu); - dw_apb_clockevent_stop(adev->timer); - } - break; - default: - pr_debug("APBT notified %lu, no action\n", action); + dw_apb_clockevent_pause(adev->timer); + if (system_state == SYSTEM_RUNNING) { + pr_debug("skipping APBT CPU %u offline\n", cpu); + } else { + pr_debug("APBT clockevent for cpu %u offline\n", cpu); + dw_apb_clockevent_stop(adev->timer); } - return NOTIFY_OK; + return 0; } static __init int apbt_late_init(void) @@ -242,9 +234,8 @@ static __init int apbt_late_init(void) if (intel_mid_timer_options == INTEL_MID_TIMER_LAPIC_APBT || !apb_timer_block_enabled) return 0; - /* This notifier should be called after workqueue is ready */ - hotcpu_notifier(apbt_cpuhp_notify, -20); - return 0; + return cpuhp_setup_state(CPUHP_X86_APB_DEAD, "X86_APB_DEAD", NULL, + apbt_cpu_dead); } fs_initcall(apbt_late_init); #else diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 8c190a85af6e..3e719ba44fbe 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -13,6 +13,7 @@ enum cpuhp_state { CPUHP_PERF_POWER, CPUHP_PERF_SUPERH, CPUHP_X86_HPET_DEAD, + CPUHP_X86_APB_DEAD, CPUHP_WORKQUEUE_PREP, CPUHP_NOTIFY_PREPARE, CPUHP_BRINGUP_CPU, -- 2.20.1