From: Sebastian Andrzej Siewior Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Sebastian Andrzej Siewior Cc: Len Brown Cc: Linus Torvalds Cc: Mathias Krause Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Anna-Maria Gleixner --- arch/x86/kernel/apic/x2apic_cluster.c | 80 +++++++++++++---------------------- include/linux/cpuhotplug.h | 1 + 2 files changed, 31 insertions(+), 50 deletions(-) diff --git a/arch/x86/kernel/apic/x2apic_cluster.c b/arch/x86/kernel/apic/x2apic_cluster.c index aca8b75..b5da5a8 100644 --- a/arch/x86/kernel/apic/x2apic_cluster.c +++ b/arch/x86/kernel/apic/x2apic_cluster.c @@ -152,68 +152,48 @@ static void init_x2apic_ldr(void) } } - /* - * At CPU state changes, update the x2apic cluster sibling info. - */ -static int -update_clusterinfo(struct notifier_block *nfb, unsigned long action, void *hcpu) +/* + * At CPU state changes, update the x2apic cluster sibling info. + */ +int x2apic_prepare_cpu(unsigned int cpu) { - unsigned int this_cpu = (unsigned long)hcpu; - unsigned int cpu; - int err = 0; - - switch (action) { - case CPU_UP_PREPARE: - if (!zalloc_cpumask_var(&per_cpu(cpus_in_cluster, this_cpu), - GFP_KERNEL)) { - err = -ENOMEM; - } else if (!zalloc_cpumask_var(&per_cpu(ipi_mask, this_cpu), - GFP_KERNEL)) { - free_cpumask_var(per_cpu(cpus_in_cluster, this_cpu)); - err = -ENOMEM; - } - break; - case CPU_UP_CANCELED: - case CPU_UP_CANCELED_FROZEN: - case CPU_DEAD: - for_each_online_cpu(cpu) { - if (x2apic_cluster(this_cpu) != x2apic_cluster(cpu)) - continue; - cpumask_clear_cpu(this_cpu, per_cpu(cpus_in_cluster, cpu)); - cpumask_clear_cpu(cpu, per_cpu(cpus_in_cluster, this_cpu)); - } - free_cpumask_var(per_cpu(cpus_in_cluster, this_cpu)); - free_cpumask_var(per_cpu(ipi_mask, this_cpu)); - break; + if (!zalloc_cpumask_var(&per_cpu(cpus_in_cluster, cpu), GFP_KERNEL)) + return -ENOMEM; + + if (!zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL)) { + free_cpumask_var(per_cpu(cpus_in_cluster, cpu)); + return -ENOMEM; } - return notifier_from_errno(err); + return 0; } -static struct notifier_block x2apic_cpu_notifier = { - .notifier_call = update_clusterinfo, -}; - -static int x2apic_init_cpu_notifier(void) +int x2apic_dead_cpu(unsigned int this_cpu) { - int cpu = smp_processor_id(); - - zalloc_cpumask_var(&per_cpu(cpus_in_cluster, cpu), GFP_KERNEL); - zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL); + int cpu; - BUG_ON(!per_cpu(cpus_in_cluster, cpu) || !per_cpu(ipi_mask, cpu)); - - cpumask_set_cpu(cpu, per_cpu(cpus_in_cluster, cpu)); - register_hotcpu_notifier(&x2apic_cpu_notifier); - return 1; + for_each_online_cpu(cpu) { + if (x2apic_cluster(this_cpu) != x2apic_cluster(cpu)) + continue; + cpumask_clear_cpu(this_cpu, per_cpu(cpus_in_cluster, cpu)); + cpumask_clear_cpu(cpu, per_cpu(cpus_in_cluster, this_cpu)); + } + free_cpumask_var(per_cpu(cpus_in_cluster, this_cpu)); + free_cpumask_var(per_cpu(ipi_mask, this_cpu)); + return 0; } static int x2apic_cluster_probe(void) { - if (x2apic_mode) - return x2apic_init_cpu_notifier(); - else + int cpu = smp_processor_id(); + + if (!x2apic_mode) return 0; + + cpumask_set_cpu(cpu, per_cpu(cpus_in_cluster, cpu)); + cpuhp_setup_state(CPUHP_X2APIC_PREPARE, "X2APIC_PREPARE", + x2apic_prepare_cpu, x2apic_dead_cpu); + return 1; } static const struct cpumask *x2apic_cluster_target_cpus(void) diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index a38fb6f..c631cd4 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -18,6 +18,7 @@ enum cpuhp_state { CPUHP_POWER_NUMA_PREPARE, CPUHP_HRTIMERS_PREPARE, CPUHP_PROFILE_PREPARE, + CPUHP_X2APIC_PREPARE, CPUHP_TIMERS_DEAD, CPUHP_NOTIFY_PREPARE, CPUHP_BRINGUP_CPU, -- 2.8.1