These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / arch / arm / kernel / smp.c

diff --git a/kernel/arch/arm/kernel/smp.c b/kernel/arch/arm/kernel/smp.c
index e561aef..e5754e3 100644 (file)
--- a/kernel/arch/arm/kernel/smp.c
+++ b/kernel/arch/arm/kernel/smp.c
@@ -21,6 +21,7 @@
 #include <linux/cpu.h>
 #include <linux/seq_file.h>
 #include <linux/irq.h>
+#include <linux/nmi.h>
 #include <linux/percpu.h>
 #include <linux/clockchips.h>
 #include <linux/completion.h>
@@ -72,13 +73,14 @@ enum ipi_msg_type {
        IPI_CPU_STOP,
        IPI_IRQ_WORK,
        IPI_COMPLETION,
+       IPI_CPU_BACKTRACE = 15,
 };
 
 static DECLARE_COMPLETION(cpu_running);
 
 static struct smp_operations smp_ops;
 
-void __init smp_set_ops(struct smp_operations *ops)
+void __init smp_set_ops(const struct smp_operations *ops)
 {
        if (ops)
                smp_ops = *ops;
@@ -86,9 +88,11 @@ void __init smp_set_ops(struct smp_operations *ops)
 
 static unsigned long get_arch_pgd(pgd_t *pgd)
 {
-       phys_addr_t pgdir = virt_to_idmap(pgd);
-       BUG_ON(pgdir & ARCH_PGD_MASK);
-       return pgdir >> ARCH_PGD_SHIFT;
+#ifdef CONFIG_ARM_LPAE
+       return __phys_to_pfn(virt_to_phys(pgd));
+#else
+       return virt_to_phys(pgd);
+#endif
 }
 
 int __cpu_up(unsigned int cpu, struct task_struct *idle)
@@ -108,7 +112,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle)
 #endif
 
 #ifdef CONFIG_MMU
-       secondary_data.pgdir = get_arch_pgd(idmap_pgd);
+       secondary_data.pgdir = virt_to_phys(idmap_pgd);
        secondary_data.swapper_pg_dir = get_arch_pgd(swapper_pg_dir);
 #endif
        sync_cache_w(&secondary_data);
@@ -173,13 +177,26 @@ static int platform_cpu_disable(unsigned int cpu)
        if (smp_ops.cpu_disable)
                return smp_ops.cpu_disable(cpu);
 
+       return 0;
+}
+
+int platform_can_hotplug_cpu(unsigned int cpu)
+{
+       /* cpu_die must be specified to support hotplug */
+       if (!smp_ops.cpu_die)
+               return 0;
+
+       if (smp_ops.cpu_can_disable)
+               return smp_ops.cpu_can_disable(cpu);
+
        /*
         * By default, allow disabling all CPUs except the first one,
         * since this is special on a lot of platforms, e.g. because
         * of clock tick interrupts.
         */
-       return cpu == 0 ? -EPERM : 0;
+       return cpu != 0;
 }
+
 /*
  * __cpu_disable runs on the processor to be shutdown.
  */
@@ -252,7 +269,7 @@ void __cpu_die(unsigned int cpu)
  * of the other hotplug-cpu capable cores, so presumably coming
  * out of idle fixes this.
  */
-void __ref cpu_die(void)
+void arch_cpu_idle_dead(void)
 {
        unsigned int cpu = smp_processor_id();
 
@@ -384,6 +401,7 @@ asmlinkage void secondary_start_kernel(void)
 
        local_irq_enable();
        local_fiq_enable();
+       local_abt_enable();
 
        /*
         * OK, it's off to the idle thread for us
@@ -629,6 +647,12 @@ void handle_IPI(int ipinr, struct pt_regs *regs)
                irq_exit();
                break;
 
+       case IPI_CPU_BACKTRACE:
+               irq_enter();
+               nmi_cpu_backtrace(regs);
+               irq_exit();
+               break;
+
        default:
                pr_crit("CPU%u: Unknown IPI message 0x%x\n",
                        cpu, ipinr);
@@ -723,3 +747,22 @@ static int __init register_cpufreq_notifier(void)
 core_initcall(register_cpufreq_notifier);
 
 #endif
+
+static void raise_nmi(cpumask_t *mask)
+{
+       /*
+        * Generate the backtrace directly if we are running in a calling
+        * context that is not preemptible by the backtrace IPI. Note
+        * that nmi_cpu_backtrace() automatically removes the current cpu
+        * from mask.
+        */
+       if (cpumask_test_cpu(smp_processor_id(), mask) && irqs_disabled())
+               nmi_cpu_backtrace(NULL);
+
+       smp_cross_call(mask, IPI_CPU_BACKTRACE);
+}
+
+void arch_trigger_all_cpu_backtrace(bool include_self)
+{
+       nmi_trigger_all_cpu_backtrace(include_self, raise_nmi);
+}