Attachment 310080 Details for Bug 452587 – Support physical cpu hotplug for x86_64

[patch] Support physical cpu hotplug for x86_64

acpi-hotplug-support.patch (text/plain), 3.95 KB, created by Alok Kataria on 2008-06-23 22:04:00 UTC

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Creator: Alok Kataria

Created: 2008-06-23 22:04:00 UTC

Size: 3.95 KB

patch

obsolete

>Author: Ashok Raj <ashok.raj@intel.com>
>Commit: 73fea175303926055440c06bc8894f0c5c58afc8
>
>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: Alok N Kataria <akataria@vmware.com>
>
>Index: linux-2.6.18-92.1.1/arch/i386/kernel/acpi/boot.c
>===================================================================
>--- linux-2.6.18-92.1.1.orig/arch/i386/kernel/acpi/boot.c	2008-06-23 11:34:20.000000000 -0700
>+++ linux-2.6.18-92.1.1/arch/i386/kernel/acpi/boot.c	2008-06-23 11:45:57.000000000 -0700
>@@ -506,16 +506,76 @@
> #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);
>Index: linux-2.6.18-92.1.1/arch/i386/kernel/mpparse.c
>===================================================================
>--- linux-2.6.18-92.1.1.orig/arch/i386/kernel/mpparse.c	2008-06-23 11:34:20.000000000 -0700
>+++ linux-2.6.18-92.1.1/arch/i386/kernel/mpparse.c	2008-06-23 11:45:57.000000000 -0700
>@@ -68,7 +68,7 @@
> /* 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;
>Index: linux-2.6.18-92.1.1/include/asm-i386/smp.h
>===================================================================
>--- linux-2.6.18-92.1.1.orig/include/asm-i386/smp.h	2006-09-19 20:42:06.000000000 -0700
>+++ linux-2.6.18-92.1.1/include/asm-i386/smp.h	2008-06-23 11:45:57.000000000 -0700
>@@ -91,6 +91,7 @@
> 
> extern int __cpu_disable(void);
> extern void __cpu_die(unsigned int cpu);
>+extern unsigned int num_processors;
> #endif /* !__ASSEMBLY__ */
> 
> #else /* CONFIG_SMP */
>Index: linux-2.6.18-92.1.1/arch/x86_64/kernel/mpparse.c
>===================================================================
>--- linux-2.6.18-92.1.1.orig/arch/x86_64/kernel/mpparse.c	2006-09-19 20:42:06.000000000 -0700
>+++ linux-2.6.18-92.1.1/arch/x86_64/kernel/mpparse.c	2008-06-23 11:45:57.000000000 -0700
>@@ -64,7 +64,7 @@
> /* Processor that is doing the boot up */
> unsigned int boot_cpu_id = -1U;
> /* Internal processor count */
>-unsigned int num_processors __initdata = 0;
>+unsigned int num_processors __cpuinitdata;
> 
> unsigned disabled_cpus __initdata;
>

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Attachments on bug 452587: 310080 | 310081 | 310082