Merge branch 'for-2.6.31' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6

[pandora-kernel.git] / arch / s390 / kernel / smp.c

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index a985a3b..2270730 100644 (file)
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -1,7 +1,7 @@
 /*
  *  arch/s390/kernel/smp.c
  *
- *    Copyright IBM Corp. 1999,2007
+ *    Copyright IBM Corp. 1999, 2009
  *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
  *              Martin Schwidefsky (schwidefsky@de.ibm.com)
  *              Heiko Carstens (heiko.carstens@de.ibm.com)
@@ -47,7 +47,7 @@
 #include <asm/timer.h>
 #include <asm/lowcore.h>
 #include <asm/sclp.h>
-#include <asm/cpu.h>
+#include <asm/cputime.h>
 #include <asm/vdso.h>
 #include "entry.h"
 
@@ -572,6 +572,7 @@ int __cpuinit __cpu_up(unsigned int cpu)
        cpu_lowcore->cpu_nr = cpu;
        cpu_lowcore->kernel_asce = S390_lowcore.kernel_asce;
        cpu_lowcore->machine_flags = S390_lowcore.machine_flags;
+       cpu_lowcore->ftrace_func = S390_lowcore.ftrace_func;
        eieio();
 
        while (signal_processor(cpu, sigp_restart) == sigp_busy)
@@ -855,13 +856,20 @@ static ssize_t show_idle_count(struct sys_device *dev,
 {
        struct s390_idle_data *idle;
        unsigned long long idle_count;
+       unsigned int sequence;
 
        idle = &per_cpu(s390_idle, dev->id);
-       spin_lock(&idle->lock);
+repeat:
+       sequence = idle->sequence;
+       smp_rmb();
+       if (sequence & 1)
+               goto repeat;
        idle_count = idle->idle_count;
        if (idle->idle_enter)
                idle_count++;
-       spin_unlock(&idle->lock);
+       smp_rmb();
+       if (idle->sequence != sequence)
+               goto repeat;
        return sprintf(buf, "%llu\n", idle_count);
 }
 static SYSDEV_ATTR(idle_count, 0444, show_idle_count, NULL);
@@ -871,15 +879,22 @@ static ssize_t show_idle_time(struct sys_device *dev,
 {
        struct s390_idle_data *idle;
        unsigned long long now, idle_time, idle_enter;
+       unsigned int sequence;
 
        idle = &per_cpu(s390_idle, dev->id);
-       spin_lock(&idle->lock);
        now = get_clock();
+repeat:
+       sequence = idle->sequence;
+       smp_rmb();
+       if (sequence & 1)
+               goto repeat;
        idle_time = idle->idle_time;
        idle_enter = idle->idle_enter;
        if (idle_enter != 0ULL && idle_enter < now)
                idle_time += now - idle_enter;
-       spin_unlock(&idle->lock);
+       smp_rmb();
+       if (idle->sequence != sequence)
+               goto repeat;
        return sprintf(buf, "%llu\n", idle_time >> 12);
 }
 static SYSDEV_ATTR(idle_time_us, 0444, show_idle_time, NULL);
@@ -907,11 +922,7 @@ static int __cpuinit smp_cpu_notify(struct notifier_block *self,
        case CPU_ONLINE:
        case CPU_ONLINE_FROZEN:
                idle = &per_cpu(s390_idle, cpu);
-               spin_lock_irq(&idle->lock);
-               idle->idle_enter = 0;
-               idle->idle_time = 0;
-               idle->idle_count = 0;
-               spin_unlock_irq(&idle->lock);
+               memset(idle, 0, sizeof(struct s390_idle_data));
                if (sysfs_create_group(&s->kobj, &cpu_online_attr_group))
                        return NOTIFY_BAD;
                break;
@@ -1030,6 +1041,42 @@ out:
 static SYSDEV_CLASS_ATTR(dispatching, 0644, dispatching_show,
                         dispatching_store);
 
+/*
+ * If the resume kernel runs on another cpu than the suspended kernel,
+ * we have to switch the cpu IDs in the logical map.
+ */
+void smp_switch_boot_cpu_in_resume(u32 resume_phys_cpu_id,
+                                  struct _lowcore *suspend_lowcore)
+{
+       int cpu, suspend_cpu_id, resume_cpu_id;
+       u32 suspend_phys_cpu_id;
+
+       suspend_phys_cpu_id = __cpu_logical_map[suspend_lowcore->cpu_nr];
+       suspend_cpu_id = suspend_lowcore->cpu_nr;
+
+       for_each_present_cpu(cpu) {
+               if (__cpu_logical_map[cpu] == resume_phys_cpu_id) {
+                       resume_cpu_id = cpu;
+                       goto found;
+               }
+       }
+       panic("Could not find resume cpu in logical map.\n");
+
+found:
+       printk("Resume  cpu ID: %i/%i\n", resume_phys_cpu_id, resume_cpu_id);
+       printk("Suspend cpu ID: %i/%i\n", suspend_phys_cpu_id, suspend_cpu_id);
+
+       __cpu_logical_map[resume_cpu_id] = suspend_phys_cpu_id;
+       __cpu_logical_map[suspend_cpu_id] = resume_phys_cpu_id;
+
+       lowcore_ptr[suspend_cpu_id]->cpu_addr = resume_phys_cpu_id;
+}
+
+u32 smp_get_phys_cpu_id(void)
+{
+       return __cpu_logical_map[smp_processor_id()];
+}
+
 static int __init topology_init(void)
 {
        int cpu;