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-rw-r--r--Documentation/cpu-hotplug.txt10
-rw-r--r--arch/s390/kernel/setup.c2
-rw-r--r--arch/s390/kernel/smp.c58
-rw-r--r--include/asm-s390/smp.h2
4 files changed, 49 insertions, 23 deletions
diff --git a/Documentation/cpu-hotplug.txt b/Documentation/cpu-hotplug.txt
index e05278087ffa..4d3355da0e26 100644
--- a/Documentation/cpu-hotplug.txt
+++ b/Documentation/cpu-hotplug.txt
@@ -11,6 +11,8 @@
Joel Schopp <jschopp@austin.ibm.com>
ia64/x86_64:
Ashok Raj <ashok.raj@intel.com>
+ s390:
+ Heiko Carstens <heiko.carstens@de.ibm.com>
Authors: Ashok Raj <ashok.raj@intel.com>
Lots of feedback: Nathan Lynch <nathanl@austin.ibm.com>,
@@ -44,11 +46,9 @@ maxcpus=n Restrict boot time cpus to n. Say if you have 4 cpus, using
maxcpus=2 will only boot 2. You can choose to bring the
other cpus later online, read FAQ's for more info.
-additional_cpus*=n Use this to limit hotpluggable cpus. This option sets
- cpu_possible_map = cpu_present_map + additional_cpus
-
-(*) Option valid only for following architectures
-- x86_64, ia64
+additional_cpus=n [x86_64, s390 only] use this to limit hotpluggable cpus.
+ This option sets
+ cpu_possible_map = cpu_present_map + additional_cpus
ia64 and x86_64 use the number of disabled local apics in ACPI tables MADT
to determine the number of potentially hot-pluggable cpus. The implementation
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index de8784267473..24f62f16c0e5 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -600,6 +600,7 @@ setup_arch(char **cmdline_p)
init_mm.brk = (unsigned long) &_end;
parse_cmdline_early(cmdline_p);
+ parse_early_param();
setup_memory();
setup_resources();
@@ -607,6 +608,7 @@ setup_arch(char **cmdline_p)
cpu_init();
__cpu_logical_map[0] = S390_lowcore.cpu_data.cpu_addr;
+ smp_setup_cpu_possible_map();
/*
* Create kernel page tables and switch to virtual addressing.
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 0d1ad5dbe2b1..53291e94ac7b 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 = CPU_MASK_ALL;
+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;
/*
@@ -503,19 +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++;
}
printk("Detected %d CPU's\n",(int) num_cpus);
printk("Boot cpu address %2X\n", boot_cpu_addr);
+
+ return num_cpus;
}
/*
@@ -676,6 +672,32 @@ __cpu_up(unsigned int cpu)
return 0;
}
+static unsigned int __initdata additional_cpus;
+
+void __init smp_setup_cpu_possible_map(void)
+{
+ unsigned int pcpus, cpu;
+
+ pcpus = smp_count_cpus() + additional_cpus;
+
+ if (pcpus > NR_CPUS)
+ pcpus = NR_CPUS;
+
+ for (cpu = 0; cpu < pcpus; cpu++)
+ cpu_set(cpu, cpu_possible_map);
+
+ cpu_present_map = cpu_possible_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);
+
int
__cpu_disable(void)
{
@@ -744,6 +766,8 @@ cpu_die(void)
for(;;);
}
+#endif /* CONFIG_HOTPLUG_CPU */
+
/*
* Cycle through the processors and setup structures.
*/
@@ -757,7 +781,6 @@ 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
@@ -806,14 +829,12 @@ 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);
S390_lowcore.percpu_offset = __per_cpu_offset[0];
current_set[0] = current;
}
void smp_cpus_done(unsigned int max_cpus)
{
- cpu_present_map = cpu_possible_map;
}
/*
@@ -845,6 +866,7 @@ 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);
diff --git a/include/asm-s390/smp.h b/include/asm-s390/smp.h
index 9c6e9c300eb9..444dae5912e6 100644
--- a/include/asm-s390/smp.h
+++ b/include/asm-s390/smp.h
@@ -31,6 +31,7 @@ typedef struct
__u16 cpu;
} sigp_info;
+extern void smp_setup_cpu_possible_map(void);
extern int smp_call_function_on(void (*func) (void *info), void *info,
int nonatomic, int wait, int cpu);
#define NO_PROC_ID 0xFF /* No processor magic marker */
@@ -104,6 +105,7 @@ smp_call_function_on(void (*func) (void *info), void *info,
#define smp_cpu_not_running(cpu) 1
#define smp_get_cpu(cpu) ({ 0; })
#define smp_put_cpu(cpu) ({ 0; })
+#define smp_setup_cpu_possible_map()
#endif
#endif
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