From 29bd7fbc071598e939526f782293dbe137be3768 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 7 Sep 2016 18:45:23 +0200 Subject: x86/microcode: Convert to hotplug state machine Install the callbacks via the state machine. CPU_UP_CANCELED_FROZEN() is not preserved: It is only there to free memory in an error case because it is assumed if the CPU does show up on resume it won't be seen ever again. As per Borislav: |IOW, you don't need mc_cpu_dead(). Signed-off-by: Sebastian Andrzej Siewior Cc: Peter Zijlstra Cc: Borislav Petkov Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160907164523.46a2xnffha4bv63g@linutronix.de Signed-off-by: Thomas Gleixner --- arch/x86/kernel/cpu/microcode/core.c | 52 ++++++++++++------------------------ 1 file changed, 17 insertions(+), 35 deletions(-) diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index df04b2d033f68..5ce5155f0695a 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -558,55 +558,36 @@ static struct syscore_ops mc_syscore_ops = { .resume = mc_bp_resume, }; -static int -mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu) +static int mc_cpu_online(unsigned int cpu) { - unsigned int cpu = (unsigned long)hcpu; struct device *dev; dev = get_cpu_device(cpu); + microcode_update_cpu(cpu); + pr_debug("CPU%d added\n", cpu); - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_ONLINE: - microcode_update_cpu(cpu); - pr_debug("CPU%d added\n", cpu); - /* - * "break" is missing on purpose here because we want to fall - * through in order to create the sysfs group. - */ - - case CPU_DOWN_FAILED: - if (sysfs_create_group(&dev->kobj, &mc_attr_group)) - pr_err("Failed to create group for CPU%d\n", cpu); - break; + if (sysfs_create_group(&dev->kobj, &mc_attr_group)) + pr_err("Failed to create group for CPU%d\n", cpu); + return 0; +} - case CPU_DOWN_PREPARE: - /* Suspend is in progress, only remove the interface */ - sysfs_remove_group(&dev->kobj, &mc_attr_group); - pr_debug("CPU%d removed\n", cpu); - break; +static int mc_cpu_down_prep(unsigned int cpu) +{ + struct device *dev; + dev = get_cpu_device(cpu); + /* Suspend is in progress, only remove the interface */ + sysfs_remove_group(&dev->kobj, &mc_attr_group); + pr_debug("CPU%d removed\n", cpu); /* - * case CPU_DEAD: - * * When a CPU goes offline, don't free up or invalidate the copy of * the microcode in kernel memory, so that we can reuse it when the * CPU comes back online without unnecessarily requesting the userspace * for it again. */ - } - - /* The CPU refused to come up during a system resume */ - if (action == CPU_UP_CANCELED_FROZEN) - microcode_fini_cpu(cpu); - - return NOTIFY_OK; + return 0; } -static struct notifier_block mc_cpu_notifier = { - .notifier_call = mc_cpu_callback, -}; - static struct attribute *cpu_root_microcode_attrs[] = { &dev_attr_reload.attr, NULL @@ -665,7 +646,8 @@ int __init microcode_init(void) goto out_ucode_group; register_syscore_ops(&mc_syscore_ops); - register_hotcpu_notifier(&mc_cpu_notifier); + cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/microcode:online", + mc_cpu_online, mc_cpu_down_prep); pr_info("Microcode Update Driver: v" MICROCODE_VERSION " , Peter Oruba\n"); -- cgit v1.2.3