![Peter Zijlstra](/assets/img/avatar_default.png)
Commit commit 8e7fbcbc2
("sched: Remove stale power aware scheduling
remnants and dysfunctional knobs") made a boo-boo with removing the
power aware scheduling muck from the x86 topology bits.
We should unconditionally use the llc_shared mask for multi-core.
Reported-and-tested-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Borislav Petkov <bp@amd64.org>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Link: http://lkml.kernel.org/n/tip-lsksc2kfyeveb13avh327p0d@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
1393 lines
34 KiB
C
1393 lines
34 KiB
C
/*
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* x86 SMP booting functions
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*
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* (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
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* (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
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* Copyright 2001 Andi Kleen, SuSE Labs.
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*
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* Much of the core SMP work is based on previous work by Thomas Radke, to
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* whom a great many thanks are extended.
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*
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* Thanks to Intel for making available several different Pentium,
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* Pentium Pro and Pentium-II/Xeon MP machines.
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* Original development of Linux SMP code supported by Caldera.
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*
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* This code is released under the GNU General Public License version 2 or
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* later.
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*
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* Fixes
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* Felix Koop : NR_CPUS used properly
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* Jose Renau : Handle single CPU case.
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* Alan Cox : By repeated request 8) - Total BogoMIPS report.
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* Greg Wright : Fix for kernel stacks panic.
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* Erich Boleyn : MP v1.4 and additional changes.
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* Matthias Sattler : Changes for 2.1 kernel map.
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* Michel Lespinasse : Changes for 2.1 kernel map.
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* Michael Chastain : Change trampoline.S to gnu as.
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* Alan Cox : Dumb bug: 'B' step PPro's are fine
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* Ingo Molnar : Added APIC timers, based on code
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* from Jose Renau
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* Ingo Molnar : various cleanups and rewrites
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* Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug.
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* Maciej W. Rozycki : Bits for genuine 82489DX APICs
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* Andi Kleen : Changed for SMP boot into long mode.
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* Martin J. Bligh : Added support for multi-quad systems
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* Dave Jones : Report invalid combinations of Athlon CPUs.
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* Rusty Russell : Hacked into shape for new "hotplug" boot process.
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* Andi Kleen : Converted to new state machine.
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* Ashok Raj : CPU hotplug support
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* Glauber Costa : i386 and x86_64 integration
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*/
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#include <linux/init.h>
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#include <linux/smp.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/percpu.h>
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#include <linux/bootmem.h>
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#include <linux/err.h>
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#include <linux/nmi.h>
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#include <linux/tboot.h>
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#include <linux/stackprotector.h>
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#include <linux/gfp.h>
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#include <linux/cpuidle.h>
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#include <asm/acpi.h>
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#include <asm/desc.h>
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#include <asm/nmi.h>
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#include <asm/irq.h>
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#include <asm/idle.h>
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#include <asm/realmode.h>
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#include <asm/cpu.h>
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#include <asm/numa.h>
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#include <asm/pgtable.h>
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#include <asm/tlbflush.h>
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#include <asm/mtrr.h>
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#include <asm/mwait.h>
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#include <asm/apic.h>
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#include <asm/io_apic.h>
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#include <asm/setup.h>
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#include <asm/uv/uv.h>
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#include <linux/mc146818rtc.h>
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#include <asm/smpboot_hooks.h>
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#include <asm/i8259.h>
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#include <asm/realmode.h>
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/* State of each CPU */
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DEFINE_PER_CPU(int, cpu_state) = { 0 };
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#ifdef CONFIG_HOTPLUG_CPU
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/*
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* We need this for trampoline_base protection from concurrent accesses when
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* off- and onlining cores wildly.
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*/
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static DEFINE_MUTEX(x86_cpu_hotplug_driver_mutex);
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void cpu_hotplug_driver_lock(void)
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{
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mutex_lock(&x86_cpu_hotplug_driver_mutex);
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}
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void cpu_hotplug_driver_unlock(void)
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{
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mutex_unlock(&x86_cpu_hotplug_driver_mutex);
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}
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ssize_t arch_cpu_probe(const char *buf, size_t count) { return -1; }
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ssize_t arch_cpu_release(const char *buf, size_t count) { return -1; }
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#endif
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/* Number of siblings per CPU package */
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int smp_num_siblings = 1;
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EXPORT_SYMBOL(smp_num_siblings);
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/* Last level cache ID of each logical CPU */
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DEFINE_PER_CPU(u16, cpu_llc_id) = BAD_APICID;
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/* representing HT siblings of each logical CPU */
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DEFINE_PER_CPU(cpumask_var_t, cpu_sibling_map);
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EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
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/* representing HT and core siblings of each logical CPU */
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DEFINE_PER_CPU(cpumask_var_t, cpu_core_map);
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EXPORT_PER_CPU_SYMBOL(cpu_core_map);
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DEFINE_PER_CPU(cpumask_var_t, cpu_llc_shared_map);
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/* Per CPU bogomips and other parameters */
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DEFINE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info);
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EXPORT_PER_CPU_SYMBOL(cpu_info);
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atomic_t init_deasserted;
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/*
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* Report back to the Boot Processor.
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* Running on AP.
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*/
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static void __cpuinit smp_callin(void)
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{
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int cpuid, phys_id;
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unsigned long timeout;
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/*
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* If waken up by an INIT in an 82489DX configuration
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* we may get here before an INIT-deassert IPI reaches
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* our local APIC. We have to wait for the IPI or we'll
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* lock up on an APIC access.
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*/
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if (apic->wait_for_init_deassert)
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apic->wait_for_init_deassert(&init_deasserted);
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/*
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* (This works even if the APIC is not enabled.)
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*/
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phys_id = read_apic_id();
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cpuid = smp_processor_id();
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if (cpumask_test_cpu(cpuid, cpu_callin_mask)) {
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panic("%s: phys CPU#%d, CPU#%d already present??\n", __func__,
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phys_id, cpuid);
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}
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pr_debug("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id);
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/*
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* STARTUP IPIs are fragile beasts as they might sometimes
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* trigger some glue motherboard logic. Complete APIC bus
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* silence for 1 second, this overestimates the time the
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* boot CPU is spending to send the up to 2 STARTUP IPIs
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* by a factor of two. This should be enough.
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*/
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/*
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* Waiting 2s total for startup (udelay is not yet working)
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*/
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timeout = jiffies + 2*HZ;
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while (time_before(jiffies, timeout)) {
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/*
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* Has the boot CPU finished it's STARTUP sequence?
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*/
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if (cpumask_test_cpu(cpuid, cpu_callout_mask))
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break;
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cpu_relax();
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}
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if (!time_before(jiffies, timeout)) {
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panic("%s: CPU%d started up but did not get a callout!\n",
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__func__, cpuid);
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}
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/*
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* the boot CPU has finished the init stage and is spinning
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* on callin_map until we finish. We are free to set up this
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* CPU, first the APIC. (this is probably redundant on most
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* boards)
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*/
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pr_debug("CALLIN, before setup_local_APIC().\n");
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if (apic->smp_callin_clear_local_apic)
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apic->smp_callin_clear_local_apic();
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setup_local_APIC();
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end_local_APIC_setup();
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/*
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* Need to setup vector mappings before we enable interrupts.
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*/
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setup_vector_irq(smp_processor_id());
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/*
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* Save our processor parameters. Note: this information
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* is needed for clock calibration.
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*/
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smp_store_cpu_info(cpuid);
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/*
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* Get our bogomips.
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* Update loops_per_jiffy in cpu_data. Previous call to
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* smp_store_cpu_info() stored a value that is close but not as
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* accurate as the value just calculated.
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*/
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calibrate_delay();
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cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy;
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pr_debug("Stack at about %p\n", &cpuid);
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/*
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* This must be done before setting cpu_online_mask
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* or calling notify_cpu_starting.
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*/
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set_cpu_sibling_map(raw_smp_processor_id());
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wmb();
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notify_cpu_starting(cpuid);
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/*
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* Allow the master to continue.
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*/
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cpumask_set_cpu(cpuid, cpu_callin_mask);
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}
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/*
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* Activate a secondary processor.
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*/
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notrace static void __cpuinit start_secondary(void *unused)
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{
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/*
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* Don't put *anything* before cpu_init(), SMP booting is too
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* fragile that we want to limit the things done here to the
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* most necessary things.
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*/
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cpu_init();
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x86_cpuinit.early_percpu_clock_init();
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preempt_disable();
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smp_callin();
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#ifdef CONFIG_X86_32
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/* switch away from the initial page table */
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load_cr3(swapper_pg_dir);
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__flush_tlb_all();
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#endif
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/* otherwise gcc will move up smp_processor_id before the cpu_init */
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barrier();
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/*
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* Check TSC synchronization with the BP:
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*/
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check_tsc_sync_target();
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/*
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* We need to hold call_lock, so there is no inconsistency
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* between the time smp_call_function() determines number of
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* IPI recipients, and the time when the determination is made
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* for which cpus receive the IPI. Holding this
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* lock helps us to not include this cpu in a currently in progress
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* smp_call_function().
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*
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* We need to hold vector_lock so there the set of online cpus
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* does not change while we are assigning vectors to cpus. Holding
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* this lock ensures we don't half assign or remove an irq from a cpu.
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*/
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ipi_call_lock();
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lock_vector_lock();
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set_cpu_online(smp_processor_id(), true);
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unlock_vector_lock();
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ipi_call_unlock();
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per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
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x86_platform.nmi_init();
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/* enable local interrupts */
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local_irq_enable();
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/* to prevent fake stack check failure in clock setup */
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boot_init_stack_canary();
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x86_cpuinit.setup_percpu_clockev();
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wmb();
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cpu_idle();
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}
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/*
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* The bootstrap kernel entry code has set these up. Save them for
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* a given CPU
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*/
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void __cpuinit smp_store_cpu_info(int id)
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{
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struct cpuinfo_x86 *c = &cpu_data(id);
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*c = boot_cpu_data;
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c->cpu_index = id;
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if (id != 0)
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identify_secondary_cpu(c);
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}
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static bool __cpuinit
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topology_sane(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o, const char *name)
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{
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int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
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return !WARN_ONCE(cpu_to_node(cpu1) != cpu_to_node(cpu2),
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"sched: CPU #%d's %s-sibling CPU #%d is not on the same node! "
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"[node: %d != %d]. Ignoring dependency.\n",
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cpu1, name, cpu2, cpu_to_node(cpu1), cpu_to_node(cpu2));
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}
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#define link_mask(_m, c1, c2) \
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do { \
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cpumask_set_cpu((c1), cpu_##_m##_mask(c2)); \
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cpumask_set_cpu((c2), cpu_##_m##_mask(c1)); \
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} while (0)
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static bool __cpuinit match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
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{
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if (cpu_has(c, X86_FEATURE_TOPOEXT)) {
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int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
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if (c->phys_proc_id == o->phys_proc_id &&
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per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2) &&
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c->compute_unit_id == o->compute_unit_id)
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return topology_sane(c, o, "smt");
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} else if (c->phys_proc_id == o->phys_proc_id &&
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c->cpu_core_id == o->cpu_core_id) {
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return topology_sane(c, o, "smt");
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}
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return false;
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}
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static bool __cpuinit match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
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{
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int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
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if (per_cpu(cpu_llc_id, cpu1) != BAD_APICID &&
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per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2))
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return topology_sane(c, o, "llc");
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return false;
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}
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static bool __cpuinit match_mc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
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{
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if (c->phys_proc_id == o->phys_proc_id)
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return topology_sane(c, o, "mc");
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return false;
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}
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void __cpuinit set_cpu_sibling_map(int cpu)
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{
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bool has_mc = boot_cpu_data.x86_max_cores > 1;
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bool has_smt = smp_num_siblings > 1;
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struct cpuinfo_x86 *c = &cpu_data(cpu);
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struct cpuinfo_x86 *o;
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int i;
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cpumask_set_cpu(cpu, cpu_sibling_setup_mask);
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if (!has_smt && !has_mc) {
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cpumask_set_cpu(cpu, cpu_sibling_mask(cpu));
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cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu));
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cpumask_set_cpu(cpu, cpu_core_mask(cpu));
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c->booted_cores = 1;
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return;
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}
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for_each_cpu(i, cpu_sibling_setup_mask) {
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o = &cpu_data(i);
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if ((i == cpu) || (has_smt && match_smt(c, o)))
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link_mask(sibling, cpu, i);
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if ((i == cpu) || (has_mc && match_llc(c, o)))
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link_mask(llc_shared, cpu, i);
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if ((i == cpu) || (has_mc && match_mc(c, o))) {
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link_mask(core, cpu, i);
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/*
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* Does this new cpu bringup a new core?
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*/
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if (cpumask_weight(cpu_sibling_mask(cpu)) == 1) {
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/*
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* for each core in package, increment
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* the booted_cores for this new cpu
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*/
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if (cpumask_first(cpu_sibling_mask(i)) == i)
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c->booted_cores++;
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/*
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* increment the core count for all
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* the other cpus in this package
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*/
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if (i != cpu)
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cpu_data(i).booted_cores++;
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} else if (i != cpu && !c->booted_cores)
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c->booted_cores = cpu_data(i).booted_cores;
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}
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}
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}
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/* maps the cpu to the sched domain representing multi-core */
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const struct cpumask *cpu_coregroup_mask(int cpu)
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{
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return cpu_llc_shared_mask(cpu);
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}
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static void impress_friends(void)
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{
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int cpu;
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unsigned long bogosum = 0;
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/*
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* Allow the user to impress friends.
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*/
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pr_debug("Before bogomips.\n");
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for_each_possible_cpu(cpu)
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if (cpumask_test_cpu(cpu, cpu_callout_mask))
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bogosum += cpu_data(cpu).loops_per_jiffy;
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printk(KERN_INFO
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"Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
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num_online_cpus(),
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bogosum/(500000/HZ),
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(bogosum/(5000/HZ))%100);
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pr_debug("Before bogocount - setting activated=1.\n");
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}
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void __inquire_remote_apic(int apicid)
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{
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unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
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const char * const names[] = { "ID", "VERSION", "SPIV" };
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int timeout;
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u32 status;
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printk(KERN_INFO "Inquiring remote APIC 0x%x...\n", apicid);
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for (i = 0; i < ARRAY_SIZE(regs); i++) {
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printk(KERN_INFO "... APIC 0x%x %s: ", apicid, names[i]);
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/*
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* Wait for idle.
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*/
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status = safe_apic_wait_icr_idle();
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if (status)
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printk(KERN_CONT
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"a previous APIC delivery may have failed\n");
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apic_icr_write(APIC_DM_REMRD | regs[i], apicid);
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timeout = 0;
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do {
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udelay(100);
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status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
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} while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
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switch (status) {
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case APIC_ICR_RR_VALID:
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status = apic_read(APIC_RRR);
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printk(KERN_CONT "%08x\n", status);
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break;
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default:
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printk(KERN_CONT "failed\n");
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}
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}
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}
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/*
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* Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
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* INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
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* won't ... remember to clear down the APIC, etc later.
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*/
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int __cpuinit
|
|
wakeup_secondary_cpu_via_nmi(int logical_apicid, unsigned long start_eip)
|
|
{
|
|
unsigned long send_status, accept_status = 0;
|
|
int maxlvt;
|
|
|
|
/* Target chip */
|
|
/* Boot on the stack */
|
|
/* Kick the second */
|
|
apic_icr_write(APIC_DM_NMI | apic->dest_logical, logical_apicid);
|
|
|
|
pr_debug("Waiting for send to finish...\n");
|
|
send_status = safe_apic_wait_icr_idle();
|
|
|
|
/*
|
|
* Give the other CPU some time to accept the IPI.
|
|
*/
|
|
udelay(200);
|
|
if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
|
|
maxlvt = lapic_get_maxlvt();
|
|
if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
|
|
apic_write(APIC_ESR, 0);
|
|
accept_status = (apic_read(APIC_ESR) & 0xEF);
|
|
}
|
|
pr_debug("NMI sent.\n");
|
|
|
|
if (send_status)
|
|
printk(KERN_ERR "APIC never delivered???\n");
|
|
if (accept_status)
|
|
printk(KERN_ERR "APIC delivery error (%lx).\n", accept_status);
|
|
|
|
return (send_status | accept_status);
|
|
}
|
|
|
|
static int __cpuinit
|
|
wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
|
|
{
|
|
unsigned long send_status, accept_status = 0;
|
|
int maxlvt, num_starts, j;
|
|
|
|
maxlvt = lapic_get_maxlvt();
|
|
|
|
/*
|
|
* Be paranoid about clearing APIC errors.
|
|
*/
|
|
if (APIC_INTEGRATED(apic_version[phys_apicid])) {
|
|
if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
|
|
apic_write(APIC_ESR, 0);
|
|
apic_read(APIC_ESR);
|
|
}
|
|
|
|
pr_debug("Asserting INIT.\n");
|
|
|
|
/*
|
|
* Turn INIT on target chip
|
|
*/
|
|
/*
|
|
* Send IPI
|
|
*/
|
|
apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT,
|
|
phys_apicid);
|
|
|
|
pr_debug("Waiting for send to finish...\n");
|
|
send_status = safe_apic_wait_icr_idle();
|
|
|
|
mdelay(10);
|
|
|
|
pr_debug("Deasserting INIT.\n");
|
|
|
|
/* Target chip */
|
|
/* Send IPI */
|
|
apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid);
|
|
|
|
pr_debug("Waiting for send to finish...\n");
|
|
send_status = safe_apic_wait_icr_idle();
|
|
|
|
mb();
|
|
atomic_set(&init_deasserted, 1);
|
|
|
|
/*
|
|
* Should we send STARTUP IPIs ?
|
|
*
|
|
* Determine this based on the APIC version.
|
|
* If we don't have an integrated APIC, don't send the STARTUP IPIs.
|
|
*/
|
|
if (APIC_INTEGRATED(apic_version[phys_apicid]))
|
|
num_starts = 2;
|
|
else
|
|
num_starts = 0;
|
|
|
|
/*
|
|
* Paravirt / VMI wants a startup IPI hook here to set up the
|
|
* target processor state.
|
|
*/
|
|
startup_ipi_hook(phys_apicid, (unsigned long) start_secondary,
|
|
stack_start);
|
|
|
|
/*
|
|
* Run STARTUP IPI loop.
|
|
*/
|
|
pr_debug("#startup loops: %d.\n", num_starts);
|
|
|
|
for (j = 1; j <= num_starts; j++) {
|
|
pr_debug("Sending STARTUP #%d.\n", j);
|
|
if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
|
|
apic_write(APIC_ESR, 0);
|
|
apic_read(APIC_ESR);
|
|
pr_debug("After apic_write.\n");
|
|
|
|
/*
|
|
* STARTUP IPI
|
|
*/
|
|
|
|
/* Target chip */
|
|
/* Boot on the stack */
|
|
/* Kick the second */
|
|
apic_icr_write(APIC_DM_STARTUP | (start_eip >> 12),
|
|
phys_apicid);
|
|
|
|
/*
|
|
* Give the other CPU some time to accept the IPI.
|
|
*/
|
|
udelay(300);
|
|
|
|
pr_debug("Startup point 1.\n");
|
|
|
|
pr_debug("Waiting for send to finish...\n");
|
|
send_status = safe_apic_wait_icr_idle();
|
|
|
|
/*
|
|
* Give the other CPU some time to accept the IPI.
|
|
*/
|
|
udelay(200);
|
|
if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
|
|
apic_write(APIC_ESR, 0);
|
|
accept_status = (apic_read(APIC_ESR) & 0xEF);
|
|
if (send_status || accept_status)
|
|
break;
|
|
}
|
|
pr_debug("After Startup.\n");
|
|
|
|
if (send_status)
|
|
printk(KERN_ERR "APIC never delivered???\n");
|
|
if (accept_status)
|
|
printk(KERN_ERR "APIC delivery error (%lx).\n", accept_status);
|
|
|
|
return (send_status | accept_status);
|
|
}
|
|
|
|
/* reduce the number of lines printed when booting a large cpu count system */
|
|
static void __cpuinit announce_cpu(int cpu, int apicid)
|
|
{
|
|
static int current_node = -1;
|
|
int node = early_cpu_to_node(cpu);
|
|
|
|
if (system_state == SYSTEM_BOOTING) {
|
|
if (node != current_node) {
|
|
if (current_node > (-1))
|
|
pr_cont(" Ok.\n");
|
|
current_node = node;
|
|
pr_info("Booting Node %3d, Processors ", node);
|
|
}
|
|
pr_cont(" #%d%s", cpu, cpu == (nr_cpu_ids - 1) ? " Ok.\n" : "");
|
|
return;
|
|
} else
|
|
pr_info("Booting Node %d Processor %d APIC 0x%x\n",
|
|
node, cpu, apicid);
|
|
}
|
|
|
|
/*
|
|
* NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
|
|
* (ie clustered apic addressing mode), this is a LOGICAL apic ID.
|
|
* Returns zero if CPU booted OK, else error code from
|
|
* ->wakeup_secondary_cpu.
|
|
*/
|
|
static int __cpuinit do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
|
|
{
|
|
volatile u32 *trampoline_status =
|
|
(volatile u32 *) __va(real_mode_header->trampoline_status);
|
|
/* start_ip had better be page-aligned! */
|
|
unsigned long start_ip = real_mode_header->trampoline_start;
|
|
|
|
unsigned long boot_error = 0;
|
|
int timeout;
|
|
|
|
alternatives_smp_switch(1);
|
|
|
|
idle->thread.sp = (unsigned long) (((struct pt_regs *)
|
|
(THREAD_SIZE + task_stack_page(idle))) - 1);
|
|
per_cpu(current_task, cpu) = idle;
|
|
|
|
#ifdef CONFIG_X86_32
|
|
/* Stack for startup_32 can be just as for start_secondary onwards */
|
|
irq_ctx_init(cpu);
|
|
#else
|
|
clear_tsk_thread_flag(idle, TIF_FORK);
|
|
initial_gs = per_cpu_offset(cpu);
|
|
per_cpu(kernel_stack, cpu) =
|
|
(unsigned long)task_stack_page(idle) -
|
|
KERNEL_STACK_OFFSET + THREAD_SIZE;
|
|
#endif
|
|
early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
|
|
initial_code = (unsigned long)start_secondary;
|
|
stack_start = idle->thread.sp;
|
|
|
|
/* So we see what's up */
|
|
announce_cpu(cpu, apicid);
|
|
|
|
/*
|
|
* This grunge runs the startup process for
|
|
* the targeted processor.
|
|
*/
|
|
|
|
atomic_set(&init_deasserted, 0);
|
|
|
|
if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
|
|
|
|
pr_debug("Setting warm reset code and vector.\n");
|
|
|
|
smpboot_setup_warm_reset_vector(start_ip);
|
|
/*
|
|
* Be paranoid about clearing APIC errors.
|
|
*/
|
|
if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
|
|
apic_write(APIC_ESR, 0);
|
|
apic_read(APIC_ESR);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Kick the secondary CPU. Use the method in the APIC driver
|
|
* if it's defined - or use an INIT boot APIC message otherwise:
|
|
*/
|
|
if (apic->wakeup_secondary_cpu)
|
|
boot_error = apic->wakeup_secondary_cpu(apicid, start_ip);
|
|
else
|
|
boot_error = wakeup_secondary_cpu_via_init(apicid, start_ip);
|
|
|
|
if (!boot_error) {
|
|
/*
|
|
* allow APs to start initializing.
|
|
*/
|
|
pr_debug("Before Callout %d.\n", cpu);
|
|
cpumask_set_cpu(cpu, cpu_callout_mask);
|
|
pr_debug("After Callout %d.\n", cpu);
|
|
|
|
/*
|
|
* Wait 5s total for a response
|
|
*/
|
|
for (timeout = 0; timeout < 50000; timeout++) {
|
|
if (cpumask_test_cpu(cpu, cpu_callin_mask))
|
|
break; /* It has booted */
|
|
udelay(100);
|
|
/*
|
|
* Allow other tasks to run while we wait for the
|
|
* AP to come online. This also gives a chance
|
|
* for the MTRR work(triggered by the AP coming online)
|
|
* to be completed in the stop machine context.
|
|
*/
|
|
schedule();
|
|
}
|
|
|
|
if (cpumask_test_cpu(cpu, cpu_callin_mask)) {
|
|
print_cpu_msr(&cpu_data(cpu));
|
|
pr_debug("CPU%d: has booted.\n", cpu);
|
|
} else {
|
|
boot_error = 1;
|
|
if (*trampoline_status == 0xA5A5A5A5)
|
|
/* trampoline started but...? */
|
|
pr_err("CPU%d: Stuck ??\n", cpu);
|
|
else
|
|
/* trampoline code not run */
|
|
pr_err("CPU%d: Not responding.\n", cpu);
|
|
if (apic->inquire_remote_apic)
|
|
apic->inquire_remote_apic(apicid);
|
|
}
|
|
}
|
|
|
|
if (boot_error) {
|
|
/* Try to put things back the way they were before ... */
|
|
numa_remove_cpu(cpu); /* was set by numa_add_cpu */
|
|
|
|
/* was set by do_boot_cpu() */
|
|
cpumask_clear_cpu(cpu, cpu_callout_mask);
|
|
|
|
/* was set by cpu_init() */
|
|
cpumask_clear_cpu(cpu, cpu_initialized_mask);
|
|
|
|
set_cpu_present(cpu, false);
|
|
per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID;
|
|
}
|
|
|
|
/* mark "stuck" area as not stuck */
|
|
*trampoline_status = 0;
|
|
|
|
if (get_uv_system_type() != UV_NON_UNIQUE_APIC) {
|
|
/*
|
|
* Cleanup possible dangling ends...
|
|
*/
|
|
smpboot_restore_warm_reset_vector();
|
|
}
|
|
return boot_error;
|
|
}
|
|
|
|
int __cpuinit native_cpu_up(unsigned int cpu, struct task_struct *tidle)
|
|
{
|
|
int apicid = apic->cpu_present_to_apicid(cpu);
|
|
unsigned long flags;
|
|
int err;
|
|
|
|
WARN_ON(irqs_disabled());
|
|
|
|
pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu);
|
|
|
|
if (apicid == BAD_APICID || apicid == boot_cpu_physical_apicid ||
|
|
!physid_isset(apicid, phys_cpu_present_map) ||
|
|
!apic->apic_id_valid(apicid)) {
|
|
printk(KERN_ERR "%s: bad cpu %d\n", __func__, cpu);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* Already booted CPU?
|
|
*/
|
|
if (cpumask_test_cpu(cpu, cpu_callin_mask)) {
|
|
pr_debug("do_boot_cpu %d Already started\n", cpu);
|
|
return -ENOSYS;
|
|
}
|
|
|
|
/*
|
|
* Save current MTRR state in case it was changed since early boot
|
|
* (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync:
|
|
*/
|
|
mtrr_save_state();
|
|
|
|
per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
|
|
|
|
err = do_boot_cpu(apicid, cpu, tidle);
|
|
if (err) {
|
|
pr_debug("do_boot_cpu failed %d\n", err);
|
|
return -EIO;
|
|
}
|
|
|
|
/*
|
|
* Check TSC synchronization with the AP (keep irqs disabled
|
|
* while doing so):
|
|
*/
|
|
local_irq_save(flags);
|
|
check_tsc_sync_source(cpu);
|
|
local_irq_restore(flags);
|
|
|
|
while (!cpu_online(cpu)) {
|
|
cpu_relax();
|
|
touch_nmi_watchdog();
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* arch_disable_smp_support() - disables SMP support for x86 at runtime
|
|
*/
|
|
void arch_disable_smp_support(void)
|
|
{
|
|
disable_ioapic_support();
|
|
}
|
|
|
|
/*
|
|
* Fall back to non SMP mode after errors.
|
|
*
|
|
* RED-PEN audit/test this more. I bet there is more state messed up here.
|
|
*/
|
|
static __init void disable_smp(void)
|
|
{
|
|
init_cpu_present(cpumask_of(0));
|
|
init_cpu_possible(cpumask_of(0));
|
|
smpboot_clear_io_apic_irqs();
|
|
|
|
if (smp_found_config)
|
|
physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
|
|
else
|
|
physid_set_mask_of_physid(0, &phys_cpu_present_map);
|
|
cpumask_set_cpu(0, cpu_sibling_mask(0));
|
|
cpumask_set_cpu(0, cpu_core_mask(0));
|
|
}
|
|
|
|
/*
|
|
* Various sanity checks.
|
|
*/
|
|
static int __init smp_sanity_check(unsigned max_cpus)
|
|
{
|
|
preempt_disable();
|
|
|
|
#if !defined(CONFIG_X86_BIGSMP) && defined(CONFIG_X86_32)
|
|
if (def_to_bigsmp && nr_cpu_ids > 8) {
|
|
unsigned int cpu;
|
|
unsigned nr;
|
|
|
|
printk(KERN_WARNING
|
|
"More than 8 CPUs detected - skipping them.\n"
|
|
"Use CONFIG_X86_BIGSMP.\n");
|
|
|
|
nr = 0;
|
|
for_each_present_cpu(cpu) {
|
|
if (nr >= 8)
|
|
set_cpu_present(cpu, false);
|
|
nr++;
|
|
}
|
|
|
|
nr = 0;
|
|
for_each_possible_cpu(cpu) {
|
|
if (nr >= 8)
|
|
set_cpu_possible(cpu, false);
|
|
nr++;
|
|
}
|
|
|
|
nr_cpu_ids = 8;
|
|
}
|
|
#endif
|
|
|
|
if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
|
|
printk(KERN_WARNING
|
|
"weird, boot CPU (#%d) not listed by the BIOS.\n",
|
|
hard_smp_processor_id());
|
|
|
|
physid_set(hard_smp_processor_id(), phys_cpu_present_map);
|
|
}
|
|
|
|
/*
|
|
* If we couldn't find an SMP configuration at boot time,
|
|
* get out of here now!
|
|
*/
|
|
if (!smp_found_config && !acpi_lapic) {
|
|
preempt_enable();
|
|
printk(KERN_NOTICE "SMP motherboard not detected.\n");
|
|
disable_smp();
|
|
if (APIC_init_uniprocessor())
|
|
printk(KERN_NOTICE "Local APIC not detected."
|
|
" Using dummy APIC emulation.\n");
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Should not be necessary because the MP table should list the boot
|
|
* CPU too, but we do it for the sake of robustness anyway.
|
|
*/
|
|
if (!apic->check_phys_apicid_present(boot_cpu_physical_apicid)) {
|
|
printk(KERN_NOTICE
|
|
"weird, boot CPU (#%d) not listed by the BIOS.\n",
|
|
boot_cpu_physical_apicid);
|
|
physid_set(hard_smp_processor_id(), phys_cpu_present_map);
|
|
}
|
|
preempt_enable();
|
|
|
|
/*
|
|
* If we couldn't find a local APIC, then get out of here now!
|
|
*/
|
|
if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid]) &&
|
|
!cpu_has_apic) {
|
|
if (!disable_apic) {
|
|
pr_err("BIOS bug, local APIC #%d not detected!...\n",
|
|
boot_cpu_physical_apicid);
|
|
pr_err("... forcing use of dummy APIC emulation."
|
|
"(tell your hw vendor)\n");
|
|
}
|
|
smpboot_clear_io_apic();
|
|
disable_ioapic_support();
|
|
return -1;
|
|
}
|
|
|
|
verify_local_APIC();
|
|
|
|
/*
|
|
* If SMP should be disabled, then really disable it!
|
|
*/
|
|
if (!max_cpus) {
|
|
printk(KERN_INFO "SMP mode deactivated.\n");
|
|
smpboot_clear_io_apic();
|
|
|
|
connect_bsp_APIC();
|
|
setup_local_APIC();
|
|
bsp_end_local_APIC_setup();
|
|
return -1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void __init smp_cpu_index_default(void)
|
|
{
|
|
int i;
|
|
struct cpuinfo_x86 *c;
|
|
|
|
for_each_possible_cpu(i) {
|
|
c = &cpu_data(i);
|
|
/* mark all to hotplug */
|
|
c->cpu_index = nr_cpu_ids;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Prepare for SMP bootup. The MP table or ACPI has been read
|
|
* earlier. Just do some sanity checking here and enable APIC mode.
|
|
*/
|
|
void __init native_smp_prepare_cpus(unsigned int max_cpus)
|
|
{
|
|
unsigned int i;
|
|
|
|
preempt_disable();
|
|
smp_cpu_index_default();
|
|
|
|
/*
|
|
* Setup boot CPU information
|
|
*/
|
|
smp_store_cpu_info(0); /* Final full version of the data */
|
|
cpumask_copy(cpu_callin_mask, cpumask_of(0));
|
|
mb();
|
|
|
|
current_thread_info()->cpu = 0; /* needed? */
|
|
for_each_possible_cpu(i) {
|
|
zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
|
|
zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
|
|
zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
|
|
}
|
|
set_cpu_sibling_map(0);
|
|
|
|
|
|
if (smp_sanity_check(max_cpus) < 0) {
|
|
printk(KERN_INFO "SMP disabled\n");
|
|
disable_smp();
|
|
goto out;
|
|
}
|
|
|
|
default_setup_apic_routing();
|
|
|
|
preempt_disable();
|
|
if (read_apic_id() != boot_cpu_physical_apicid) {
|
|
panic("Boot APIC ID in local APIC unexpected (%d vs %d)",
|
|
read_apic_id(), boot_cpu_physical_apicid);
|
|
/* Or can we switch back to PIC here? */
|
|
}
|
|
preempt_enable();
|
|
|
|
connect_bsp_APIC();
|
|
|
|
/*
|
|
* Switch from PIC to APIC mode.
|
|
*/
|
|
setup_local_APIC();
|
|
|
|
/*
|
|
* Enable IO APIC before setting up error vector
|
|
*/
|
|
if (!skip_ioapic_setup && nr_ioapics)
|
|
enable_IO_APIC();
|
|
|
|
bsp_end_local_APIC_setup();
|
|
|
|
if (apic->setup_portio_remap)
|
|
apic->setup_portio_remap();
|
|
|
|
smpboot_setup_io_apic();
|
|
/*
|
|
* Set up local APIC timer on boot CPU.
|
|
*/
|
|
|
|
printk(KERN_INFO "CPU%d: ", 0);
|
|
print_cpu_info(&cpu_data(0));
|
|
x86_init.timers.setup_percpu_clockev();
|
|
|
|
if (is_uv_system())
|
|
uv_system_init();
|
|
|
|
set_mtrr_aps_delayed_init();
|
|
out:
|
|
preempt_enable();
|
|
}
|
|
|
|
void arch_disable_nonboot_cpus_begin(void)
|
|
{
|
|
/*
|
|
* Avoid the smp alternatives switch during the disable_nonboot_cpus().
|
|
* In the suspend path, we will be back in the SMP mode shortly anyways.
|
|
*/
|
|
skip_smp_alternatives = true;
|
|
}
|
|
|
|
void arch_disable_nonboot_cpus_end(void)
|
|
{
|
|
skip_smp_alternatives = false;
|
|
}
|
|
|
|
void arch_enable_nonboot_cpus_begin(void)
|
|
{
|
|
set_mtrr_aps_delayed_init();
|
|
}
|
|
|
|
void arch_enable_nonboot_cpus_end(void)
|
|
{
|
|
mtrr_aps_init();
|
|
}
|
|
|
|
/*
|
|
* Early setup to make printk work.
|
|
*/
|
|
void __init native_smp_prepare_boot_cpu(void)
|
|
{
|
|
int me = smp_processor_id();
|
|
switch_to_new_gdt(me);
|
|
/* already set me in cpu_online_mask in boot_cpu_init() */
|
|
cpumask_set_cpu(me, cpu_callout_mask);
|
|
per_cpu(cpu_state, me) = CPU_ONLINE;
|
|
}
|
|
|
|
void __init native_smp_cpus_done(unsigned int max_cpus)
|
|
{
|
|
pr_debug("Boot done.\n");
|
|
|
|
nmi_selftest();
|
|
impress_friends();
|
|
#ifdef CONFIG_X86_IO_APIC
|
|
setup_ioapic_dest();
|
|
#endif
|
|
mtrr_aps_init();
|
|
}
|
|
|
|
static int __initdata setup_possible_cpus = -1;
|
|
static int __init _setup_possible_cpus(char *str)
|
|
{
|
|
get_option(&str, &setup_possible_cpus);
|
|
return 0;
|
|
}
|
|
early_param("possible_cpus", _setup_possible_cpus);
|
|
|
|
|
|
/*
|
|
* cpu_possible_mask should be static, it cannot change as cpu's
|
|
* are onlined, or offlined. The reason is per-cpu data-structures
|
|
* are allocated by some modules at init time, and dont expect to
|
|
* do this dynamically on cpu arrival/departure.
|
|
* cpu_present_mask on the other hand can change dynamically.
|
|
* In case when cpu_hotplug is not compiled, then we resort to current
|
|
* behaviour, which is cpu_possible == cpu_present.
|
|
* - Ashok Raj
|
|
*
|
|
* Three ways to find out the number of additional hotplug CPUs:
|
|
* - If the BIOS specified disabled CPUs in ACPI/mptables use that.
|
|
* - The user can overwrite it with possible_cpus=NUM
|
|
* - Otherwise don't reserve additional CPUs.
|
|
* We do this because additional CPUs waste a lot of memory.
|
|
* -AK
|
|
*/
|
|
__init void prefill_possible_map(void)
|
|
{
|
|
int i, possible;
|
|
|
|
/* no processor from mptable or madt */
|
|
if (!num_processors)
|
|
num_processors = 1;
|
|
|
|
i = setup_max_cpus ?: 1;
|
|
if (setup_possible_cpus == -1) {
|
|
possible = num_processors;
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
if (setup_max_cpus)
|
|
possible += disabled_cpus;
|
|
#else
|
|
if (possible > i)
|
|
possible = i;
|
|
#endif
|
|
} else
|
|
possible = setup_possible_cpus;
|
|
|
|
total_cpus = max_t(int, possible, num_processors + disabled_cpus);
|
|
|
|
/* nr_cpu_ids could be reduced via nr_cpus= */
|
|
if (possible > nr_cpu_ids) {
|
|
printk(KERN_WARNING
|
|
"%d Processors exceeds NR_CPUS limit of %d\n",
|
|
possible, nr_cpu_ids);
|
|
possible = nr_cpu_ids;
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
if (!setup_max_cpus)
|
|
#endif
|
|
if (possible > i) {
|
|
printk(KERN_WARNING
|
|
"%d Processors exceeds max_cpus limit of %u\n",
|
|
possible, setup_max_cpus);
|
|
possible = i;
|
|
}
|
|
|
|
printk(KERN_INFO "SMP: Allowing %d CPUs, %d hotplug CPUs\n",
|
|
possible, max_t(int, possible - num_processors, 0));
|
|
|
|
for (i = 0; i < possible; i++)
|
|
set_cpu_possible(i, true);
|
|
for (; i < NR_CPUS; i++)
|
|
set_cpu_possible(i, false);
|
|
|
|
nr_cpu_ids = possible;
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
|
|
static void remove_siblinginfo(int cpu)
|
|
{
|
|
int sibling;
|
|
struct cpuinfo_x86 *c = &cpu_data(cpu);
|
|
|
|
for_each_cpu(sibling, cpu_core_mask(cpu)) {
|
|
cpumask_clear_cpu(cpu, cpu_core_mask(sibling));
|
|
/*/
|
|
* last thread sibling in this cpu core going down
|
|
*/
|
|
if (cpumask_weight(cpu_sibling_mask(cpu)) == 1)
|
|
cpu_data(sibling).booted_cores--;
|
|
}
|
|
|
|
for_each_cpu(sibling, cpu_sibling_mask(cpu))
|
|
cpumask_clear_cpu(cpu, cpu_sibling_mask(sibling));
|
|
cpumask_clear(cpu_sibling_mask(cpu));
|
|
cpumask_clear(cpu_core_mask(cpu));
|
|
c->phys_proc_id = 0;
|
|
c->cpu_core_id = 0;
|
|
cpumask_clear_cpu(cpu, cpu_sibling_setup_mask);
|
|
}
|
|
|
|
static void __ref remove_cpu_from_maps(int cpu)
|
|
{
|
|
set_cpu_online(cpu, false);
|
|
cpumask_clear_cpu(cpu, cpu_callout_mask);
|
|
cpumask_clear_cpu(cpu, cpu_callin_mask);
|
|
/* was set by cpu_init() */
|
|
cpumask_clear_cpu(cpu, cpu_initialized_mask);
|
|
numa_remove_cpu(cpu);
|
|
}
|
|
|
|
void cpu_disable_common(void)
|
|
{
|
|
int cpu = smp_processor_id();
|
|
|
|
remove_siblinginfo(cpu);
|
|
|
|
/* It's now safe to remove this processor from the online map */
|
|
lock_vector_lock();
|
|
remove_cpu_from_maps(cpu);
|
|
unlock_vector_lock();
|
|
fixup_irqs();
|
|
}
|
|
|
|
int native_cpu_disable(void)
|
|
{
|
|
int cpu = smp_processor_id();
|
|
|
|
/*
|
|
* Perhaps use cpufreq to drop frequency, but that could go
|
|
* into generic code.
|
|
*
|
|
* We won't take down the boot processor on i386 due to some
|
|
* interrupts only being able to be serviced by the BSP.
|
|
* Especially so if we're not using an IOAPIC -zwane
|
|
*/
|
|
if (cpu == 0)
|
|
return -EBUSY;
|
|
|
|
clear_local_APIC();
|
|
|
|
cpu_disable_common();
|
|
return 0;
|
|
}
|
|
|
|
void native_cpu_die(unsigned int cpu)
|
|
{
|
|
/* We don't do anything here: idle task is faking death itself. */
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < 10; i++) {
|
|
/* They ack this in play_dead by setting CPU_DEAD */
|
|
if (per_cpu(cpu_state, cpu) == CPU_DEAD) {
|
|
if (system_state == SYSTEM_RUNNING)
|
|
pr_info("CPU %u is now offline\n", cpu);
|
|
|
|
if (1 == num_online_cpus())
|
|
alternatives_smp_switch(0);
|
|
return;
|
|
}
|
|
msleep(100);
|
|
}
|
|
pr_err("CPU %u didn't die...\n", cpu);
|
|
}
|
|
|
|
void play_dead_common(void)
|
|
{
|
|
idle_task_exit();
|
|
reset_lazy_tlbstate();
|
|
amd_e400_remove_cpu(raw_smp_processor_id());
|
|
|
|
mb();
|
|
/* Ack it */
|
|
__this_cpu_write(cpu_state, CPU_DEAD);
|
|
|
|
/*
|
|
* With physical CPU hotplug, we should halt the cpu
|
|
*/
|
|
local_irq_disable();
|
|
}
|
|
|
|
/*
|
|
* We need to flush the caches before going to sleep, lest we have
|
|
* dirty data in our caches when we come back up.
|
|
*/
|
|
static inline void mwait_play_dead(void)
|
|
{
|
|
unsigned int eax, ebx, ecx, edx;
|
|
unsigned int highest_cstate = 0;
|
|
unsigned int highest_subcstate = 0;
|
|
int i;
|
|
void *mwait_ptr;
|
|
struct cpuinfo_x86 *c = __this_cpu_ptr(&cpu_info);
|
|
|
|
if (!(this_cpu_has(X86_FEATURE_MWAIT) && mwait_usable(c)))
|
|
return;
|
|
if (!this_cpu_has(X86_FEATURE_CLFLSH))
|
|
return;
|
|
if (__this_cpu_read(cpu_info.cpuid_level) < CPUID_MWAIT_LEAF)
|
|
return;
|
|
|
|
eax = CPUID_MWAIT_LEAF;
|
|
ecx = 0;
|
|
native_cpuid(&eax, &ebx, &ecx, &edx);
|
|
|
|
/*
|
|
* eax will be 0 if EDX enumeration is not valid.
|
|
* Initialized below to cstate, sub_cstate value when EDX is valid.
|
|
*/
|
|
if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) {
|
|
eax = 0;
|
|
} else {
|
|
edx >>= MWAIT_SUBSTATE_SIZE;
|
|
for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {
|
|
if (edx & MWAIT_SUBSTATE_MASK) {
|
|
highest_cstate = i;
|
|
highest_subcstate = edx & MWAIT_SUBSTATE_MASK;
|
|
}
|
|
}
|
|
eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) |
|
|
(highest_subcstate - 1);
|
|
}
|
|
|
|
/*
|
|
* This should be a memory location in a cache line which is
|
|
* unlikely to be touched by other processors. The actual
|
|
* content is immaterial as it is not actually modified in any way.
|
|
*/
|
|
mwait_ptr = ¤t_thread_info()->flags;
|
|
|
|
wbinvd();
|
|
|
|
while (1) {
|
|
/*
|
|
* The CLFLUSH is a workaround for erratum AAI65 for
|
|
* the Xeon 7400 series. It's not clear it is actually
|
|
* needed, but it should be harmless in either case.
|
|
* The WBINVD is insufficient due to the spurious-wakeup
|
|
* case where we return around the loop.
|
|
*/
|
|
clflush(mwait_ptr);
|
|
__monitor(mwait_ptr, 0, 0);
|
|
mb();
|
|
__mwait(eax, 0);
|
|
}
|
|
}
|
|
|
|
static inline void hlt_play_dead(void)
|
|
{
|
|
if (__this_cpu_read(cpu_info.x86) >= 4)
|
|
wbinvd();
|
|
|
|
while (1) {
|
|
native_halt();
|
|
}
|
|
}
|
|
|
|
void native_play_dead(void)
|
|
{
|
|
play_dead_common();
|
|
tboot_shutdown(TB_SHUTDOWN_WFS);
|
|
|
|
mwait_play_dead(); /* Only returns on failure */
|
|
if (cpuidle_play_dead())
|
|
hlt_play_dead();
|
|
}
|
|
|
|
#else /* ... !CONFIG_HOTPLUG_CPU */
|
|
int native_cpu_disable(void)
|
|
{
|
|
return -ENOSYS;
|
|
}
|
|
|
|
void native_cpu_die(unsigned int cpu)
|
|
{
|
|
/* We said "no" in __cpu_disable */
|
|
BUG();
|
|
}
|
|
|
|
void native_play_dead(void)
|
|
{
|
|
BUG();
|
|
}
|
|
|
|
#endif
|