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Diffstat (limited to 'arch/s390/kernel/smp.c')
-rw-r--r--arch/s390/kernel/smp.c73
1 files changed, 60 insertions, 13 deletions
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index cc8c484984e3..be2cae083406 100644
--- 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)
@@ -687,13 +687,14 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
#ifndef CONFIG_64BIT
if (MACHINE_HAS_IEEE)
lowcore->extended_save_area_addr = (u32) save_area;
-#else
- if (vdso_alloc_per_cpu(smp_processor_id(), lowcore))
- BUG();
#endif
set_prefix((u32)(unsigned long) lowcore);
local_mcck_enable();
local_irq_enable();
+#ifdef CONFIG_64BIT
+ if (vdso_alloc_per_cpu(smp_processor_id(), &S390_lowcore))
+ BUG();
+#endif
for_each_possible_cpu(cpu)
if (cpu != smp_processor_id())
smp_create_idle(cpu);
@@ -856,13 +857,20 @@ 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);
@@ -872,15 +880,22 @@ 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);
@@ -908,11 +923,7 @@ 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;
@@ -1031,6 +1042,42 @@ 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;