From af7aa04683e85ccb9088e31fe67a0397167b7abd Mon Sep 17 00:00:00 2001 From: Qais Yousef Date: Mon, 23 Mar 2020 13:51:02 +0000 Subject: x86/smp: Replace cpu_up/down() with add/remove_cpu() The core device API performs extra housekeeping bits that are missing from directly calling cpu_up/down(). See commit a6717c01ddc2 ("powerpc/rtas: use device model APIs and serialization during LPM") for an example description of what might go wrong. This also prepares to make cpu_up/down() a private interface of the CPU subsystem. Signed-off-by: Qais Yousef Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/20200323135110.30522-10-qais.yousef@arm.com --- arch/x86/kernel/topology.c | 22 ++++++---------------- arch/x86/mm/mmio-mod.c | 4 ++-- arch/x86/xen/smp.c | 2 +- 3 files changed, 9 insertions(+), 19 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c index be5bc2e47c71..b8810ebbc8ae 100644 --- a/arch/x86/kernel/topology.c +++ b/arch/x86/kernel/topology.c @@ -59,39 +59,29 @@ __setup("cpu0_hotplug", enable_cpu0_hotplug); */ int _debug_hotplug_cpu(int cpu, int action) { - struct device *dev = get_cpu_device(cpu); int ret; if (!cpu_is_hotpluggable(cpu)) return -EINVAL; - lock_device_hotplug(); - switch (action) { case 0: - ret = cpu_down(cpu); - if (!ret) { + ret = remove_cpu(cpu); + if (!ret) pr_info("DEBUG_HOTPLUG_CPU0: CPU %u is now offline\n", cpu); - dev->offline = true; - kobject_uevent(&dev->kobj, KOBJ_OFFLINE); - } else + else pr_debug("Can't offline CPU%d.\n", cpu); break; case 1: - ret = cpu_up(cpu); - if (!ret) { - dev->offline = false; - kobject_uevent(&dev->kobj, KOBJ_ONLINE); - } else { + ret = add_cpu(cpu); + if (ret) pr_debug("Can't online CPU%d.\n", cpu); - } + break; default: ret = -EINVAL; } - unlock_device_hotplug(); - return ret; } diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c index 673de6063345..109325d77b3e 100644 --- a/arch/x86/mm/mmio-mod.c +++ b/arch/x86/mm/mmio-mod.c @@ -386,7 +386,7 @@ static void enter_uniprocessor(void) put_online_cpus(); for_each_cpu(cpu, downed_cpus) { - err = cpu_down(cpu); + err = remove_cpu(cpu); if (!err) pr_info("CPU%d is down.\n", cpu); else @@ -406,7 +406,7 @@ static void leave_uniprocessor(void) return; pr_notice("Re-enabling CPUs...\n"); for_each_cpu(cpu, downed_cpus) { - err = cpu_up(cpu); + err = add_cpu(cpu); if (!err) pr_info("enabled CPU%d.\n", cpu); else diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 7a43b2ae19f1..2097fa0ebdb5 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -132,7 +132,7 @@ void __init xen_smp_cpus_done(unsigned int max_cpus) if (xen_vcpu_nr(cpu) < MAX_VIRT_CPUS) continue; - rc = cpu_down(cpu); + rc = remove_cpu(cpu); if (rc == 0) { /* -- cgit v1.2.3