Commit 73fea175 authored by Ashok Raj's avatar Ashok Raj Committed by Andi Kleen

[PATCH] i386: Support physical cpu hotplug for x86_64

This patch enables ACPI based physical CPU hotplug support for x86_64.
Implements acpi_map_lsapic() and acpi_unmap_lsapic() to support physical cpu
hotplug.
Signed-off-by: default avatarAshok Raj <ashok.raj@intel.com>
Signed-off-by: default avatarAndi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@muc.de>
Cc: "Brown, Len" <len.brown@intel.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
parent 40bee2ee
......@@ -26,6 +26,7 @@
#include <linux/init.h>
#include <linux/acpi.h>
#include <linux/efi.h>
#include <linux/cpumask.h>
#include <linux/module.h>
#include <linux/dmi.h>
#include <linux/irq.h>
......@@ -512,16 +513,76 @@ EXPORT_SYMBOL(acpi_register_gsi);
#ifdef CONFIG_ACPI_HOTPLUG_CPU
int acpi_map_lsapic(acpi_handle handle, int *pcpu)
{
/* TBD */
return -EINVAL;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
union acpi_object *obj;
struct acpi_table_lapic *lapic;
cpumask_t tmp_map, new_map;
u8 physid;
int cpu;
if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
return -EINVAL;
if (!buffer.length || !buffer.pointer)
return -EINVAL;
obj = buffer.pointer;
if (obj->type != ACPI_TYPE_BUFFER ||
obj->buffer.length < sizeof(*lapic)) {
kfree(buffer.pointer);
return -EINVAL;
}
lapic = (struct acpi_table_lapic *)obj->buffer.pointer;
if ((lapic->header.type != ACPI_MADT_LAPIC) ||
(!lapic->flags.enabled)) {
kfree(buffer.pointer);
return -EINVAL;
}
physid = lapic->id;
kfree(buffer.pointer);
buffer.length = ACPI_ALLOCATE_BUFFER;
buffer.pointer = NULL;
tmp_map = cpu_present_map;
mp_register_lapic(physid, lapic->flags.enabled);
/*
* If mp_register_lapic successfully generates a new logical cpu
* number, then the following will get us exactly what was mapped
*/
cpus_andnot(new_map, cpu_present_map, tmp_map);
if (cpus_empty(new_map)) {
printk ("Unable to map lapic to logical cpu number\n");
return -EINVAL;
}
cpu = first_cpu(new_map);
*pcpu = cpu;
return 0;
}
EXPORT_SYMBOL(acpi_map_lsapic);
int acpi_unmap_lsapic(int cpu)
{
/* TBD */
return -EINVAL;
int i;
for_each_possible_cpu(i) {
if (x86_acpiid_to_apicid[i] == x86_cpu_to_apicid[cpu]) {
x86_acpiid_to_apicid[i] = -1;
break;
}
}
x86_cpu_to_apicid[cpu] = -1;
cpu_clear(cpu, cpu_present_map);
num_processors--;
return (0);
}
EXPORT_SYMBOL(acpi_unmap_lsapic);
......
......@@ -69,7 +69,7 @@ unsigned int def_to_bigsmp = 0;
/* Processor that is doing the boot up */
unsigned int boot_cpu_physical_apicid = -1U;
/* Internal processor count */
static unsigned int __devinitdata num_processors;
unsigned int __cpuinitdata num_processors;
/* Bitmask of physically existing CPUs */
physid_mask_t phys_cpu_present_map;
......
......@@ -84,6 +84,7 @@ static inline int hard_smp_processor_id(void)
extern int __cpu_disable(void);
extern void __cpu_die(unsigned int cpu);
extern unsigned int num_processors;
#endif /* !__ASSEMBLY__ */
......
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