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authorAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
committerAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
commitb4b6116a13633898cf868f2f103c96a90c4c20f8 (patch)
tree93d1b7e2cfcdf473d8d4ff3ad141fa864f8491f6 /arch/powerpc/kernel/smp.c
parentedd4be777c953e5faafc80d091d3084b4343f5d3 (diff)
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fedora kernel: d9aad82f3319f3cfd1aebc01234254ef0c37ad84v3.3.2-1
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'arch/powerpc/kernel/smp.c')
-rw-r--r--arch/powerpc/kernel/smp.c785
1 files changed, 785 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
new file mode 100644
index 00000000000..46695febc09
--- /dev/null
+++ b/arch/powerpc/kernel/smp.c
@@ -0,0 +1,785 @@
+/*
+ * SMP support for ppc.
+ *
+ * Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great
+ * deal of code from the sparc and intel versions.
+ *
+ * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
+ *
+ * PowerPC-64 Support added by Dave Engebretsen, Peter Bergner, and
+ * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#undef DEBUG
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/cache.h>
+#include <linux/err.h>
+#include <linux/device.h>
+#include <linux/cpu.h>
+#include <linux/notifier.h>
+#include <linux/topology.h>
+
+#include <asm/ptrace.h>
+#include <linux/atomic.h>
+#include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/prom.h>
+#include <asm/smp.h>
+#include <asm/time.h>
+#include <asm/machdep.h>
+#include <asm/cputhreads.h>
+#include <asm/cputable.h>
+#include <asm/system.h>
+#include <asm/mpic.h>
+#include <asm/vdso_datapage.h>
+#ifdef CONFIG_PPC64
+#include <asm/paca.h>
+#endif
+
+#ifdef DEBUG
+#include <asm/udbg.h>
+#define DBG(fmt...) udbg_printf(fmt)
+#else
+#define DBG(fmt...)
+#endif
+
+
+/* Store all idle threads, this can be reused instead of creating
+* a new thread. Also avoids complicated thread destroy functionality
+* for idle threads.
+*/
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * Needed only for CONFIG_HOTPLUG_CPU because __cpuinitdata is
+ * removed after init for !CONFIG_HOTPLUG_CPU.
+ */
+static DEFINE_PER_CPU(struct task_struct *, idle_thread_array);
+#define get_idle_for_cpu(x) (per_cpu(idle_thread_array, x))
+#define set_idle_for_cpu(x, p) (per_cpu(idle_thread_array, x) = (p))
+
+/* State of each CPU during hotplug phases */
+static DEFINE_PER_CPU(int, cpu_state) = { 0 };
+
+#else
+static struct task_struct *idle_thread_array[NR_CPUS] __cpuinitdata ;
+#define get_idle_for_cpu(x) (idle_thread_array[(x)])
+#define set_idle_for_cpu(x, p) (idle_thread_array[(x)] = (p))
+#endif
+
+struct thread_info *secondary_ti;
+
+DEFINE_PER_CPU(cpumask_var_t, cpu_sibling_map);
+DEFINE_PER_CPU(cpumask_var_t, cpu_core_map);
+
+EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
+EXPORT_PER_CPU_SYMBOL(cpu_core_map);
+
+/* SMP operations for this machine */
+struct smp_ops_t *smp_ops;
+
+/* Can't be static due to PowerMac hackery */
+volatile unsigned int cpu_callin_map[NR_CPUS];
+
+int smt_enabled_at_boot = 1;
+
+static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL;
+
+#ifdef CONFIG_PPC64
+int __devinit smp_generic_kick_cpu(int nr)
+{
+ BUG_ON(nr < 0 || nr >= NR_CPUS);
+
+ /*
+ * The processor is currently spinning, waiting for the
+ * cpu_start field to become non-zero After we set cpu_start,
+ * the processor will continue on to secondary_start
+ */
+ if (!paca[nr].cpu_start) {
+ paca[nr].cpu_start = 1;
+ smp_mb();
+ return 0;
+ }
+
+#ifdef CONFIG_HOTPLUG_CPU
+ /*
+ * Ok it's not there, so it might be soft-unplugged, let's
+ * try to bring it back
+ */
+ per_cpu(cpu_state, nr) = CPU_UP_PREPARE;
+ smp_wmb();
+ smp_send_reschedule(nr);
+#endif /* CONFIG_HOTPLUG_CPU */
+
+ return 0;
+}
+#endif /* CONFIG_PPC64 */
+
+static irqreturn_t call_function_action(int irq, void *data)
+{
+ generic_smp_call_function_interrupt();
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t reschedule_action(int irq, void *data)
+{
+ scheduler_ipi();
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t call_function_single_action(int irq, void *data)
+{
+ generic_smp_call_function_single_interrupt();
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t debug_ipi_action(int irq, void *data)
+{
+ if (crash_ipi_function_ptr) {
+ crash_ipi_function_ptr(get_irq_regs());
+ return IRQ_HANDLED;
+ }
+
+#ifdef CONFIG_DEBUGGER
+ debugger_ipi(get_irq_regs());
+#endif /* CONFIG_DEBUGGER */
+
+ return IRQ_HANDLED;
+}
+
+static irq_handler_t smp_ipi_action[] = {
+ [PPC_MSG_CALL_FUNCTION] = call_function_action,
+ [PPC_MSG_RESCHEDULE] = reschedule_action,
+ [PPC_MSG_CALL_FUNC_SINGLE] = call_function_single_action,
+ [PPC_MSG_DEBUGGER_BREAK] = debug_ipi_action,
+};
+
+const char *smp_ipi_name[] = {
+ [PPC_MSG_CALL_FUNCTION] = "ipi call function",
+ [PPC_MSG_RESCHEDULE] = "ipi reschedule",
+ [PPC_MSG_CALL_FUNC_SINGLE] = "ipi call function single",
+ [PPC_MSG_DEBUGGER_BREAK] = "ipi debugger",
+};
+
+/* optional function to request ipi, for controllers with >= 4 ipis */
+int smp_request_message_ipi(int virq, int msg)
+{
+ int err;
+
+ if (msg < 0 || msg > PPC_MSG_DEBUGGER_BREAK) {
+ return -EINVAL;
+ }
+#if !defined(CONFIG_DEBUGGER) && !defined(CONFIG_KEXEC)
+ if (msg == PPC_MSG_DEBUGGER_BREAK) {
+ return 1;
+ }
+#endif
+ err = request_irq(virq, smp_ipi_action[msg],
+ IRQF_PERCPU | IRQF_NO_THREAD,
+ smp_ipi_name[msg], 0);
+ WARN(err < 0, "unable to request_irq %d for %s (rc %d)\n",
+ virq, smp_ipi_name[msg], err);
+
+ return err;
+}
+
+#ifdef CONFIG_PPC_SMP_MUXED_IPI
+struct cpu_messages {
+ int messages; /* current messages */
+ unsigned long data; /* data for cause ipi */
+};
+static DEFINE_PER_CPU_SHARED_ALIGNED(struct cpu_messages, ipi_message);
+
+void smp_muxed_ipi_set_data(int cpu, unsigned long data)
+{
+ struct cpu_messages *info = &per_cpu(ipi_message, cpu);
+
+ info->data = data;
+}
+
+void smp_muxed_ipi_message_pass(int cpu, int msg)
+{
+ struct cpu_messages *info = &per_cpu(ipi_message, cpu);
+ char *message = (char *)&info->messages;
+
+ message[msg] = 1;
+ mb();
+ smp_ops->cause_ipi(cpu, info->data);
+}
+
+irqreturn_t smp_ipi_demux(void)
+{
+ struct cpu_messages *info = &__get_cpu_var(ipi_message);
+ unsigned int all;
+
+ mb(); /* order any irq clear */
+
+ do {
+ all = xchg_local(&info->messages, 0);
+
+#ifdef __BIG_ENDIAN
+ if (all & (1 << (24 - 8 * PPC_MSG_CALL_FUNCTION)))
+ generic_smp_call_function_interrupt();
+ if (all & (1 << (24 - 8 * PPC_MSG_RESCHEDULE)))
+ scheduler_ipi();
+ if (all & (1 << (24 - 8 * PPC_MSG_CALL_FUNC_SINGLE)))
+ generic_smp_call_function_single_interrupt();
+ if (all & (1 << (24 - 8 * PPC_MSG_DEBUGGER_BREAK)))
+ debug_ipi_action(0, NULL);
+#else
+#error Unsupported ENDIAN
+#endif
+ } while (info->messages);
+
+ return IRQ_HANDLED;
+}
+#endif /* CONFIG_PPC_SMP_MUXED_IPI */
+
+static inline void do_message_pass(int cpu, int msg)
+{
+ if (smp_ops->message_pass)
+ smp_ops->message_pass(cpu, msg);
+#ifdef CONFIG_PPC_SMP_MUXED_IPI
+ else
+ smp_muxed_ipi_message_pass(cpu, msg);
+#endif
+}
+
+void smp_send_reschedule(int cpu)
+{
+ if (likely(smp_ops))
+ do_message_pass(cpu, PPC_MSG_RESCHEDULE);
+}
+EXPORT_SYMBOL_GPL(smp_send_reschedule);
+
+void arch_send_call_function_single_ipi(int cpu)
+{
+ do_message_pass(cpu, PPC_MSG_CALL_FUNC_SINGLE);
+}
+
+void arch_send_call_function_ipi_mask(const struct cpumask *mask)
+{
+ unsigned int cpu;
+
+ for_each_cpu(cpu, mask)
+ do_message_pass(cpu, PPC_MSG_CALL_FUNCTION);
+}
+
+#if defined(CONFIG_DEBUGGER) || defined(CONFIG_KEXEC)
+void smp_send_debugger_break(void)
+{
+ int cpu;
+ int me = raw_smp_processor_id();
+
+ if (unlikely(!smp_ops))
+ return;
+
+ for_each_online_cpu(cpu)
+ if (cpu != me)
+ do_message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
+}
+#endif
+
+#ifdef CONFIG_KEXEC
+void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
+{
+ crash_ipi_function_ptr = crash_ipi_callback;
+ if (crash_ipi_callback) {
+ mb();
+ smp_send_debugger_break();
+ }
+}
+#endif
+
+static void stop_this_cpu(void *dummy)
+{
+ /* Remove this CPU */
+ set_cpu_online(smp_processor_id(), false);
+
+ local_irq_disable();
+ while (1)
+ ;
+}
+
+void smp_send_stop(void)
+{
+ smp_call_function(stop_this_cpu, NULL, 0);
+}
+
+struct thread_info *current_set[NR_CPUS];
+
+static void __devinit smp_store_cpu_info(int id)
+{
+ per_cpu(cpu_pvr, id) = mfspr(SPRN_PVR);
+#ifdef CONFIG_PPC_FSL_BOOK3E
+ per_cpu(next_tlbcam_idx, id)
+ = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
+#endif
+}
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+ unsigned int cpu;
+
+ DBG("smp_prepare_cpus\n");
+
+ /*
+ * setup_cpu may need to be called on the boot cpu. We havent
+ * spun any cpus up but lets be paranoid.
+ */
+ BUG_ON(boot_cpuid != smp_processor_id());
+
+ /* Fixup boot cpu */
+ smp_store_cpu_info(boot_cpuid);
+ cpu_callin_map[boot_cpuid] = 1;
+
+ for_each_possible_cpu(cpu) {
+ zalloc_cpumask_var_node(&per_cpu(cpu_sibling_map, cpu),
+ GFP_KERNEL, cpu_to_node(cpu));
+ zalloc_cpumask_var_node(&per_cpu(cpu_core_map, cpu),
+ GFP_KERNEL, cpu_to_node(cpu));
+ }
+
+ cpumask_set_cpu(boot_cpuid, cpu_sibling_mask(boot_cpuid));
+ cpumask_set_cpu(boot_cpuid, cpu_core_mask(boot_cpuid));
+
+ if (smp_ops)
+ if (smp_ops->probe)
+ max_cpus = smp_ops->probe();
+ else
+ max_cpus = NR_CPUS;
+ else
+ max_cpus = 1;
+}
+
+void __devinit smp_prepare_boot_cpu(void)
+{
+ BUG_ON(smp_processor_id() != boot_cpuid);
+#ifdef CONFIG_PPC64
+ paca[boot_cpuid].__current = current;
+#endif
+ current_set[boot_cpuid] = task_thread_info(current);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+int generic_cpu_disable(void)
+{
+ unsigned int cpu = smp_processor_id();
+
+ if (cpu == boot_cpuid)
+ return -EBUSY;
+
+ set_cpu_online(cpu, false);
+#ifdef CONFIG_PPC64
+ vdso_data->processorCount--;
+#endif
+ migrate_irqs();
+ return 0;
+}
+
+void generic_cpu_die(unsigned int cpu)
+{
+ int i;
+
+ for (i = 0; i < 100; i++) {
+ smp_rmb();
+ if (per_cpu(cpu_state, cpu) == CPU_DEAD)
+ return;
+ msleep(100);
+ }
+ printk(KERN_ERR "CPU%d didn't die...\n", cpu);
+}
+
+void generic_mach_cpu_die(void)
+{
+ unsigned int cpu;
+
+ local_irq_disable();
+ idle_task_exit();
+ cpu = smp_processor_id();
+ printk(KERN_DEBUG "CPU%d offline\n", cpu);
+ __get_cpu_var(cpu_state) = CPU_DEAD;
+ smp_wmb();
+ while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
+ cpu_relax();
+}
+
+void generic_set_cpu_dead(unsigned int cpu)
+{
+ per_cpu(cpu_state, cpu) = CPU_DEAD;
+}
+
+int generic_check_cpu_restart(unsigned int cpu)
+{
+ return per_cpu(cpu_state, cpu) == CPU_UP_PREPARE;
+}
+#endif
+
+struct create_idle {
+ struct work_struct work;
+ struct task_struct *idle;
+ struct completion done;
+ int cpu;
+};
+
+static void __cpuinit do_fork_idle(struct work_struct *work)
+{
+ struct create_idle *c_idle =
+ container_of(work, struct create_idle, work);
+
+ c_idle->idle = fork_idle(c_idle->cpu);
+ complete(&c_idle->done);
+}
+
+static int __cpuinit create_idle(unsigned int cpu)
+{
+ struct thread_info *ti;
+ struct create_idle c_idle = {
+ .cpu = cpu,
+ .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
+ };
+ INIT_WORK_ONSTACK(&c_idle.work, do_fork_idle);
+
+ c_idle.idle = get_idle_for_cpu(cpu);
+
+ /* We can't use kernel_thread since we must avoid to
+ * reschedule the child. We use a workqueue because
+ * we want to fork from a kernel thread, not whatever
+ * userspace process happens to be trying to online us.
+ */
+ if (!c_idle.idle) {
+ schedule_work(&c_idle.work);
+ wait_for_completion(&c_idle.done);
+ } else
+ init_idle(c_idle.idle, cpu);
+ if (IS_ERR(c_idle.idle)) {
+ pr_err("Failed fork for CPU %u: %li", cpu, PTR_ERR(c_idle.idle));
+ return PTR_ERR(c_idle.idle);
+ }
+ ti = task_thread_info(c_idle.idle);
+
+#ifdef CONFIG_PPC64
+ paca[cpu].__current = c_idle.idle;
+ paca[cpu].kstack = (unsigned long)ti + THREAD_SIZE - STACK_FRAME_OVERHEAD;
+#endif
+ ti->cpu = cpu;
+ current_set[cpu] = ti;
+
+ return 0;
+}
+
+int __cpuinit __cpu_up(unsigned int cpu)
+{
+ int rc, c;
+
+ if (smp_ops == NULL ||
+ (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu)))
+ return -EINVAL;
+
+ /* Make sure we have an idle thread */
+ rc = create_idle(cpu);
+ if (rc)
+ return rc;
+
+ secondary_ti = current_set[cpu];
+
+ /* Make sure callin-map entry is 0 (can be leftover a CPU
+ * hotplug
+ */
+ cpu_callin_map[cpu] = 0;
+
+ /* The information for processor bringup must
+ * be written out to main store before we release
+ * the processor.
+ */
+ smp_mb();
+
+ /* wake up cpus */
+ DBG("smp: kicking cpu %d\n", cpu);
+ rc = smp_ops->kick_cpu(cpu);
+ if (rc) {
+ pr_err("smp: failed starting cpu %d (rc %d)\n", cpu, rc);
+ return rc;
+ }
+
+ /*
+ * wait to see if the cpu made a callin (is actually up).
+ * use this value that I found through experimentation.
+ * -- Cort
+ */
+ if (system_state < SYSTEM_RUNNING)
+ for (c = 50000; c && !cpu_callin_map[cpu]; c--)
+ udelay(100);
+#ifdef CONFIG_HOTPLUG_CPU
+ else
+ /*
+ * CPUs can take much longer to come up in the
+ * hotplug case. Wait five seconds.
+ */
+ for (c = 5000; c && !cpu_callin_map[cpu]; c--)
+ msleep(1);
+#endif
+
+ if (!cpu_callin_map[cpu]) {
+ printk(KERN_ERR "Processor %u is stuck.\n", cpu);
+ return -ENOENT;
+ }
+
+ DBG("Processor %u found.\n", cpu);
+
+ if (smp_ops->give_timebase)
+ smp_ops->give_timebase();
+
+ /* Wait until cpu puts itself in the online map */
+ while (!cpu_online(cpu))
+ cpu_relax();
+
+ return 0;
+}
+
+/* Return the value of the reg property corresponding to the given
+ * logical cpu.
+ */
+int cpu_to_core_id(int cpu)
+{
+ struct device_node *np;
+ const int *reg;
+ int id = -1;
+
+ np = of_get_cpu_node(cpu, NULL);
+ if (!np)
+ goto out;
+
+ reg = of_get_property(np, "reg", NULL);
+ if (!reg)
+ goto out;
+
+ id = *reg;
+out:
+ of_node_put(np);
+ return id;
+}
+
+/* Helper routines for cpu to core mapping */
+int cpu_core_index_of_thread(int cpu)
+{
+ return cpu >> threads_shift;
+}
+EXPORT_SYMBOL_GPL(cpu_core_index_of_thread);
+
+int cpu_first_thread_of_core(int core)
+{
+ return core << threads_shift;
+}
+EXPORT_SYMBOL_GPL(cpu_first_thread_of_core);
+
+/* Must be called when no change can occur to cpu_present_mask,
+ * i.e. during cpu online or offline.
+ */
+static struct device_node *cpu_to_l2cache(int cpu)
+{
+ struct device_node *np;
+ struct device_node *cache;
+
+ if (!cpu_present(cpu))
+ return NULL;
+
+ np = of_get_cpu_node(cpu, NULL);
+ if (np == NULL)
+ return NULL;
+
+ cache = of_find_next_cache_node(np);
+
+ of_node_put(np);
+
+ return cache;
+}
+
+/* Activate a secondary processor. */
+void __devinit start_secondary(void *unused)
+{
+ unsigned int cpu = smp_processor_id();
+ struct device_node *l2_cache;
+ int i, base;
+
+ atomic_inc(&init_mm.mm_count);
+ current->active_mm = &init_mm;
+
+ smp_store_cpu_info(cpu);
+ set_dec(tb_ticks_per_jiffy);
+ preempt_disable();
+ cpu_callin_map[cpu] = 1;
+
+ if (smp_ops->setup_cpu)
+ smp_ops->setup_cpu(cpu);
+ if (smp_ops->take_timebase)
+ smp_ops->take_timebase();
+
+ secondary_cpu_time_init();
+
+#ifdef CONFIG_PPC64
+ if (system_state == SYSTEM_RUNNING)
+ vdso_data->processorCount++;
+#endif
+ ipi_call_lock();
+ notify_cpu_starting(cpu);
+ set_cpu_online(cpu, true);
+ /* Update sibling maps */
+ base = cpu_first_thread_sibling(cpu);
+ for (i = 0; i < threads_per_core; i++) {
+ if (cpu_is_offline(base + i))
+ continue;
+ cpumask_set_cpu(cpu, cpu_sibling_mask(base + i));
+ cpumask_set_cpu(base + i, cpu_sibling_mask(cpu));
+
+ /* cpu_core_map should be a superset of
+ * cpu_sibling_map even if we don't have cache
+ * information, so update the former here, too.
+ */
+ cpumask_set_cpu(cpu, cpu_core_mask(base + i));
+ cpumask_set_cpu(base + i, cpu_core_mask(cpu));
+ }
+ l2_cache = cpu_to_l2cache(cpu);
+ for_each_online_cpu(i) {
+ struct device_node *np = cpu_to_l2cache(i);
+ if (!np)
+ continue;
+ if (np == l2_cache) {
+ cpumask_set_cpu(cpu, cpu_core_mask(i));
+ cpumask_set_cpu(i, cpu_core_mask(cpu));
+ }
+ of_node_put(np);
+ }
+ of_node_put(l2_cache);
+ ipi_call_unlock();
+
+ local_irq_enable();
+
+ cpu_idle();
+
+ BUG();
+}
+
+int setup_profiling_timer(unsigned int multiplier)
+{
+ return 0;
+}
+
+void __init smp_cpus_done(unsigned int max_cpus)
+{
+ cpumask_var_t old_mask;
+
+ /* We want the setup_cpu() here to be called from CPU 0, but our
+ * init thread may have been "borrowed" by another CPU in the meantime
+ * se we pin us down to CPU 0 for a short while
+ */
+ alloc_cpumask_var(&old_mask, GFP_NOWAIT);
+ cpumask_copy(old_mask, tsk_cpus_allowed(current));
+ set_cpus_allowed_ptr(current, cpumask_of(boot_cpuid));
+
+ if (smp_ops && smp_ops->setup_cpu)
+ smp_ops->setup_cpu(boot_cpuid);
+
+ set_cpus_allowed_ptr(current, old_mask);
+
+ free_cpumask_var(old_mask);
+
+ if (smp_ops && smp_ops->bringup_done)
+ smp_ops->bringup_done();
+
+ dump_numa_cpu_topology();
+
+}
+
+int arch_sd_sibling_asym_packing(void)
+{
+ if (cpu_has_feature(CPU_FTR_ASYM_SMT)) {
+ printk_once(KERN_INFO "Enabling Asymmetric SMT scheduling\n");
+ return SD_ASYM_PACKING;
+ }
+ return 0;
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+int __cpu_disable(void)
+{
+ struct device_node *l2_cache;
+ int cpu = smp_processor_id();
+ int base, i;
+ int err;
+
+ if (!smp_ops->cpu_disable)
+ return -ENOSYS;
+
+ err = smp_ops->cpu_disable();
+ if (err)
+ return err;
+
+ /* Update sibling maps */
+ base = cpu_first_thread_sibling(cpu);
+ for (i = 0; i < threads_per_core; i++) {
+ cpumask_clear_cpu(cpu, cpu_sibling_mask(base + i));
+ cpumask_clear_cpu(base + i, cpu_sibling_mask(cpu));
+ cpumask_clear_cpu(cpu, cpu_core_mask(base + i));
+ cpumask_clear_cpu(base + i, cpu_core_mask(cpu));
+ }
+
+ l2_cache = cpu_to_l2cache(cpu);
+ for_each_present_cpu(i) {
+ struct device_node *np = cpu_to_l2cache(i);
+ if (!np)
+ continue;
+ if (np == l2_cache) {
+ cpumask_clear_cpu(cpu, cpu_core_mask(i));
+ cpumask_clear_cpu(i, cpu_core_mask(cpu));
+ }
+ of_node_put(np);
+ }
+ of_node_put(l2_cache);
+
+
+ return 0;
+}
+
+void __cpu_die(unsigned int cpu)
+{
+ if (smp_ops->cpu_die)
+ smp_ops->cpu_die(cpu);
+}
+
+static DEFINE_MUTEX(powerpc_cpu_hotplug_driver_mutex);
+
+void cpu_hotplug_driver_lock()
+{
+ mutex_lock(&powerpc_cpu_hotplug_driver_mutex);
+}
+
+void cpu_hotplug_driver_unlock()
+{
+ mutex_unlock(&powerpc_cpu_hotplug_driver_mutex);
+}
+
+void cpu_die(void)
+{
+ if (ppc_md.cpu_die)
+ ppc_md.cpu_die();
+
+ /* If we return, we re-enter start_secondary */
+ start_secondary_resume();
+}
+
+#endif