Commit 949ec325 authored Jan 30, 2008 by Yinghai Lu Committed by Ingo Molnar Jan 30, 2008

x86: set cpu_index to nr_cpus instead of 0



Some BIOSes that support two/four dualcore/quadcore systems, will get:

ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled)
Processor #0 15:1 APIC version 16
ACPI: LAPIC (acpi_id[0x02] lapic_id[0x01] enabled)
Processor #1 15:1 APIC version 16
ACPI: LAPIC (acpi_id[0x03] lapic_id[0x02] enabled)
Processor #2 15:1 APIC version 16
ACPI: LAPIC (acpi_id[0x04] lapic_id[0x03] enabled)
Processor #3 15:1 APIC version 16
ACPI: LAPIC (acpi_id[0x05] lapic_id[0x84] disabled)
ACPI: LAPIC (acpi_id[0x06] lapic_id[0x85] disabled)
ACPI: LAPIC (acpi_id[0x07] lapic_id[0x86] disabled)
ACPI: LAPIC (acpi_id[0x08] lapic_id[0x87] disabled)
ACPI: LAPIC (acpi_id[0x09] lapic_id[0x88] disabled)
ACPI: LAPIC (acpi_id[0x0a] lapic_id[0x89] disabled)
ACPI: LAPIC (acpi_id[0x0b] lapic_id[0x8a] disabled)
ACPI: LAPIC (acpi_id[0x0c] lapic_id[0x8b] disabled)
ACPI: LAPIC (acpi_id[0x0d] lapic_id[0x8c] disabled)
ACPI: LAPIC (acpi_id[0x0e] lapic_id[0x8d] disabled)
ACPI: LAPIC (acpi_id[0x0f] lapic_id[0x8e] disabled)
ACPI: LAPIC (acpi_id[0x10] lapic_id[0x8f] disabled)

SMP: Allowing 16 CPUs, 12 hotplug CPUs

the /proc/cpuinfo will show a bunch of NULL cpus with cpu_index=0

so assign impossible cpu_index value at first instead of 0.

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

parent b3ca74a2

arch/x86/kernel/smpboot_64.c

+13 −0

Original line number	Diff line number	Diff line
		@@ -861,6 +861,18 @@ void __init smp_set_apicids(void)
		x86_cpu_to_apicid_ptr = NULL;
		}

		static void __init smp_cpu_index_default(void)
		{
		int i;
		struct cpuinfo_x86 *c;

		for_each_cpu_mask(i, cpu_possible_map) {
		c = &cpu_data(i);
		/* mark all to hotplug */
		c->cpu_index = NR_CPUS;
		}
		}

		/*
		* Prepare for SMP bootup. The MP table or ACPI has been read
		* earlier. Just do some sanity checking here and enable APIC mode.
		@@ -868,6 +880,7 @@ void __init smp_set_apicids(void)
		void __init smp_prepare_cpus(unsigned int max_cpus)
		{
		nmi_watchdog_default();
		smp_cpu_index_default();
		current_cpu_data = boot_cpu_data;
		current_thread_info()->cpu = 0; /* needed? */
		smp_set_apicids();

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