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Diffstat (limited to 'arch/s390/kernel/smp.c')
-rw-r--r--arch/s390/kernel/smp.c73
1 files changed, 52 insertions, 21 deletions
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index cbfcfd02a43..7dbe00c76c6 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -1,8 +1,7 @@
/*
* arch/s390/kernel/smp.c
*
- * S390 version
- * Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ * Copyright (C) IBM Corp. 1999,2006
* 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)
@@ -41,8 +40,6 @@
#include <asm/cpcmd.h>
#include <asm/tlbflush.h>
-/* prototypes */
-
extern volatile int __cpu_logical_map[];
/*
@@ -51,13 +48,11 @@ extern volatile int __cpu_logical_map[];
struct _lowcore *lowcore_ptr[NR_CPUS];
-cpumask_t cpu_online_map;
-cpumask_t cpu_possible_map;
+cpumask_t cpu_online_map = CPU_MASK_NONE;
+cpumask_t cpu_possible_map = CPU_MASK_NONE;
static struct task_struct *current_set[NR_CPUS];
-EXPORT_SYMBOL(cpu_online_map);
-
/*
* Reboot, halt and power_off routines for SMP.
*/
@@ -490,10 +485,10 @@ void smp_ctl_clear_bit(int cr, int bit) {
* Lets check how many CPUs we have.
*/
-void
-__init smp_check_cpus(unsigned int max_cpus)
+static unsigned int
+__init smp_count_cpus(void)
{
- int cpu, num_cpus;
+ unsigned int cpu, num_cpus;
__u16 boot_cpu_addr;
/*
@@ -503,22 +498,20 @@ __init smp_check_cpus(unsigned int max_cpus)
boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr;
current_thread_info()->cpu = 0;
num_cpus = 1;
- for (cpu = 0; cpu <= 65535 && num_cpus < max_cpus; cpu++) {
+ for (cpu = 0; cpu <= 65535; cpu++) {
if ((__u16) cpu == boot_cpu_addr)
continue;
- __cpu_logical_map[num_cpus] = (__u16) cpu;
- if (signal_processor(num_cpus, sigp_sense) ==
+ __cpu_logical_map[1] = (__u16) cpu;
+ if (signal_processor(1, sigp_sense) ==
sigp_not_operational)
continue;
- cpu_set(num_cpus, cpu_present_map);
num_cpus++;
}
- for (cpu = 1; cpu < max_cpus; cpu++)
- cpu_set(cpu, cpu_possible_map);
-
printk("Detected %d CPU's\n",(int) num_cpus);
printk("Boot cpu address %2X\n", boot_cpu_addr);
+
+ return num_cpus;
}
/*
@@ -679,6 +672,44 @@ __cpu_up(unsigned int cpu)
return 0;
}
+static unsigned int __initdata additional_cpus;
+static unsigned int __initdata possible_cpus;
+
+void __init smp_setup_cpu_possible_map(void)
+{
+ unsigned int phy_cpus, pos_cpus, cpu;
+
+ phy_cpus = smp_count_cpus();
+ pos_cpus = min(phy_cpus + additional_cpus, (unsigned int) NR_CPUS);
+
+ if (possible_cpus)
+ pos_cpus = min(possible_cpus, (unsigned int) NR_CPUS);
+
+ for (cpu = 0; cpu < pos_cpus; cpu++)
+ cpu_set(cpu, cpu_possible_map);
+
+ phy_cpus = min(phy_cpus, pos_cpus);
+
+ for (cpu = 0; cpu < phy_cpus; cpu++)
+ cpu_set(cpu, cpu_present_map);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+
+static int __init setup_additional_cpus(char *s)
+{
+ additional_cpus = simple_strtoul(s, NULL, 0);
+ return 0;
+}
+early_param("additional_cpus", setup_additional_cpus);
+
+static int __init setup_possible_cpus(char *s)
+{
+ possible_cpus = simple_strtoul(s, NULL, 0);
+ return 0;
+}
+early_param("possible_cpus", setup_possible_cpus);
+
int
__cpu_disable(void)
{
@@ -747,6 +778,8 @@ cpu_die(void)
for(;;);
}
+#endif /* CONFIG_HOTPLUG_CPU */
+
/*
* Cycle through the processors and setup structures.
*/
@@ -760,7 +793,6 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
/* request the 0x1201 emergency signal external interrupt */
if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0)
panic("Couldn't request external interrupt 0x1201");
- smp_check_cpus(max_cpus);
memset(lowcore_ptr,0,sizeof(lowcore_ptr));
/*
* Initialize prefix pages and stacks for all possible cpus
@@ -809,8 +841,6 @@ void __devinit smp_prepare_boot_cpu(void)
BUG_ON(smp_processor_id() != 0);
cpu_set(0, cpu_online_map);
- cpu_set(0, cpu_present_map);
- cpu_set(0, cpu_possible_map);
S390_lowcore.percpu_offset = __per_cpu_offset[0];
current_set[0] = current;
}
@@ -849,6 +879,7 @@ static int __init topology_init(void)
subsys_initcall(topology_init);
+EXPORT_SYMBOL(cpu_online_map);
EXPORT_SYMBOL(cpu_possible_map);
EXPORT_SYMBOL(lowcore_ptr);
EXPORT_SYMBOL(smp_ctl_set_bit);