From 73fea175303926055440c06bc8894f0c5c58afc8 Mon Sep 17 00:00:00 2001 From: Ashok Raj Date: Tue, 26 Sep 2006 10:52:35 +0200 Subject: [PATCH] [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: Ashok Raj Signed-off-by: Andi Kleen Cc: Andi Kleen Cc: "Brown, Len" Signed-off-by: Andrew Morton --- arch/i386/kernel/acpi/boot.c | 69 +++++++++++++++++++++++++++++++++--- arch/i386/kernel/mpparse.c | 2 +- include/asm-i386/smp.h | 1 + 3 files changed, 67 insertions(+), 5 deletions(-) diff --git a/arch/i386/kernel/acpi/boot.c b/arch/i386/kernel/acpi/boot.c index 0fba420d668a..8a6c5b412348 100644 --- a/arch/i386/kernel/acpi/boot.c +++ b/arch/i386/kernel/acpi/boot.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include #include @@ -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); diff --git a/arch/i386/kernel/mpparse.c b/arch/i386/kernel/mpparse.c index 772a4233bfe6..442aaf8c77eb 100644 --- a/arch/i386/kernel/mpparse.c +++ b/arch/i386/kernel/mpparse.c @@ -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; diff --git a/include/asm-i386/smp.h b/include/asm-i386/smp.h index f87826039a51..32ac8c91d5c5 100644 --- a/include/asm-i386/smp.h +++ b/include/asm-i386/smp.h @@ -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__ */ -- 2.20.1