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-rw-r--r--arch/x86_64/kernel/smpboot_64.c1085
1 files changed, 0 insertions, 1085 deletions
diff --git a/arch/x86_64/kernel/smpboot_64.c b/arch/x86_64/kernel/smpboot_64.c
deleted file mode 100644
index 32f50783edc..00000000000
--- a/arch/x86_64/kernel/smpboot_64.c
+++ /dev/null
@@ -1,1085 +0,0 @@
-/*
- * x86 SMP booting functions
- *
- * (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
- * (c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com>
- * Copyright 2001 Andi Kleen, SuSE Labs.
- *
- * Much of the core SMP work is based on previous work by Thomas Radke, to
- * whom a great many thanks are extended.
- *
- * Thanks to Intel for making available several different Pentium,
- * Pentium Pro and Pentium-II/Xeon MP machines.
- * Original development of Linux SMP code supported by Caldera.
- *
- * This code is released under the GNU General Public License version 2
- *
- * Fixes
- * Felix Koop : NR_CPUS used properly
- * Jose Renau : Handle single CPU case.
- * Alan Cox : By repeated request 8) - Total BogoMIP report.
- * Greg Wright : Fix for kernel stacks panic.
- * Erich Boleyn : MP v1.4 and additional changes.
- * Matthias Sattler : Changes for 2.1 kernel map.
- * Michel Lespinasse : Changes for 2.1 kernel map.
- * Michael Chastain : Change trampoline.S to gnu as.
- * Alan Cox : Dumb bug: 'B' step PPro's are fine
- * Ingo Molnar : Added APIC timers, based on code
- * from Jose Renau
- * Ingo Molnar : various cleanups and rewrites
- * Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug.
- * Maciej W. Rozycki : Bits for genuine 82489DX APICs
- * Andi Kleen : Changed for SMP boot into long mode.
- * Rusty Russell : Hacked into shape for new "hotplug" boot process.
- * Andi Kleen : Converted to new state machine.
- * Various cleanups.
- * Probably mostly hotplug CPU ready now.
- * Ashok Raj : CPU hotplug support
- */
-
-
-#include <linux/init.h>
-
-#include <linux/mm.h>
-#include <linux/kernel_stat.h>
-#include <linux/bootmem.h>
-#include <linux/thread_info.h>
-#include <linux/module.h>
-#include <linux/delay.h>
-#include <linux/mc146818rtc.h>
-#include <linux/smp.h>
-#include <linux/kdebug.h>
-
-#include <asm/mtrr.h>
-#include <asm/pgalloc.h>
-#include <asm/desc.h>
-#include <asm/tlbflush.h>
-#include <asm/proto.h>
-#include <asm/nmi.h>
-#include <asm/irq.h>
-#include <asm/hw_irq.h>
-#include <asm/numa.h>
-
-/* Number of siblings per CPU package */
-int smp_num_siblings = 1;
-EXPORT_SYMBOL(smp_num_siblings);
-
-/* Last level cache ID of each logical CPU */
-u8 cpu_llc_id[NR_CPUS] __cpuinitdata = {[0 ... NR_CPUS-1] = BAD_APICID};
-
-/* Bitmask of currently online CPUs */
-cpumask_t cpu_online_map __read_mostly;
-
-EXPORT_SYMBOL(cpu_online_map);
-
-/*
- * Private maps to synchronize booting between AP and BP.
- * Probably not needed anymore, but it makes for easier debugging. -AK
- */
-cpumask_t cpu_callin_map;
-cpumask_t cpu_callout_map;
-EXPORT_SYMBOL(cpu_callout_map);
-
-cpumask_t cpu_possible_map;
-EXPORT_SYMBOL(cpu_possible_map);
-
-/* Per CPU bogomips and other parameters */
-struct cpuinfo_x86 cpu_data[NR_CPUS] __cacheline_aligned;
-EXPORT_SYMBOL(cpu_data);
-
-/* Set when the idlers are all forked */
-int smp_threads_ready;
-
-/* representing HT siblings of each logical CPU */
-cpumask_t cpu_sibling_map[NR_CPUS] __read_mostly;
-EXPORT_SYMBOL(cpu_sibling_map);
-
-/* representing HT and core siblings of each logical CPU */
-cpumask_t cpu_core_map[NR_CPUS] __read_mostly;
-EXPORT_SYMBOL(cpu_core_map);
-
-/*
- * Trampoline 80x86 program as an array.
- */
-
-extern unsigned char trampoline_data[];
-extern unsigned char trampoline_end[];
-
-/* State of each CPU */
-DEFINE_PER_CPU(int, cpu_state) = { 0 };
-
-/*
- * Store all idle threads, this can be reused instead of creating
- * a new thread. Also avoids complicated thread destroy functionality
- * for idle threads.
- */
-struct task_struct *idle_thread_array[NR_CPUS] __cpuinitdata ;
-
-#define get_idle_for_cpu(x) (idle_thread_array[(x)])
-#define set_idle_for_cpu(x,p) (idle_thread_array[(x)] = (p))
-
-/*
- * Currently trivial. Write the real->protected mode
- * bootstrap into the page concerned. The caller
- * has made sure it's suitably aligned.
- */
-
-static unsigned long __cpuinit setup_trampoline(void)
-{
- void *tramp = __va(SMP_TRAMPOLINE_BASE);
- memcpy(tramp, trampoline_data, trampoline_end - trampoline_data);
- return virt_to_phys(tramp);
-}
-
-/*
- * The bootstrap kernel entry code has set these up. Save them for
- * a given CPU
- */
-
-static void __cpuinit smp_store_cpu_info(int id)
-{
- struct cpuinfo_x86 *c = cpu_data + id;
-
- *c = boot_cpu_data;
- identify_cpu(c);
- print_cpu_info(c);
-}
-
-static atomic_t init_deasserted __cpuinitdata;
-
-/*
- * Report back to the Boot Processor.
- * Running on AP.
- */
-void __cpuinit smp_callin(void)
-{
- int cpuid, phys_id;
- unsigned long timeout;
-
- /*
- * If waken up by an INIT in an 82489DX configuration
- * we may get here before an INIT-deassert IPI reaches
- * our local APIC. We have to wait for the IPI or we'll
- * lock up on an APIC access.
- */
- while (!atomic_read(&init_deasserted))
- cpu_relax();
-
- /*
- * (This works even if the APIC is not enabled.)
- */
- phys_id = GET_APIC_ID(apic_read(APIC_ID));
- cpuid = smp_processor_id();
- if (cpu_isset(cpuid, cpu_callin_map)) {
- panic("smp_callin: phys CPU#%d, CPU#%d already present??\n",
- phys_id, cpuid);
- }
- Dprintk("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id);
-
- /*
- * STARTUP IPIs are fragile beasts as they might sometimes
- * trigger some glue motherboard logic. Complete APIC bus
- * silence for 1 second, this overestimates the time the
- * boot CPU is spending to send the up to 2 STARTUP IPIs
- * by a factor of two. This should be enough.
- */
-
- /*
- * Waiting 2s total for startup (udelay is not yet working)
- */
- timeout = jiffies + 2*HZ;
- while (time_before(jiffies, timeout)) {
- /*
- * Has the boot CPU finished it's STARTUP sequence?
- */
- if (cpu_isset(cpuid, cpu_callout_map))
- break;
- cpu_relax();
- }
-
- if (!time_before(jiffies, timeout)) {
- panic("smp_callin: CPU%d started up but did not get a callout!\n",
- cpuid);
- }
-
- /*
- * the boot CPU has finished the init stage and is spinning
- * on callin_map until we finish. We are free to set up this
- * CPU, first the APIC. (this is probably redundant on most
- * boards)
- */
-
- Dprintk("CALLIN, before setup_local_APIC().\n");
- setup_local_APIC();
-
- /*
- * Get our bogomips.
- *
- * Need to enable IRQs because it can take longer and then
- * the NMI watchdog might kill us.
- */
- local_irq_enable();
- calibrate_delay();
- local_irq_disable();
- Dprintk("Stack at about %p\n",&cpuid);
-
- disable_APIC_timer();
-
- /*
- * Save our processor parameters
- */
- smp_store_cpu_info(cpuid);
-
- /*
- * Allow the master to continue.
- */
- cpu_set(cpuid, cpu_callin_map);
-}
-
-/* maps the cpu to the sched domain representing multi-core */
-cpumask_t cpu_coregroup_map(int cpu)
-{
- struct cpuinfo_x86 *c = cpu_data + cpu;
- /*
- * For perf, we return last level cache shared map.
- * And for power savings, we return cpu_core_map
- */
- if (sched_mc_power_savings || sched_smt_power_savings)
- return cpu_core_map[cpu];
- else
- return c->llc_shared_map;
-}
-
-/* representing cpus for which sibling maps can be computed */
-static cpumask_t cpu_sibling_setup_map;
-
-static inline void set_cpu_sibling_map(int cpu)
-{
- int i;
- struct cpuinfo_x86 *c = cpu_data;
-
- cpu_set(cpu, cpu_sibling_setup_map);
-
- if (smp_num_siblings > 1) {
- for_each_cpu_mask(i, cpu_sibling_setup_map) {
- if (c[cpu].phys_proc_id == c[i].phys_proc_id &&
- c[cpu].cpu_core_id == c[i].cpu_core_id) {
- cpu_set(i, cpu_sibling_map[cpu]);
- cpu_set(cpu, cpu_sibling_map[i]);
- cpu_set(i, cpu_core_map[cpu]);
- cpu_set(cpu, cpu_core_map[i]);
- cpu_set(i, c[cpu].llc_shared_map);
- cpu_set(cpu, c[i].llc_shared_map);
- }
- }
- } else {
- cpu_set(cpu, cpu_sibling_map[cpu]);
- }
-
- cpu_set(cpu, c[cpu].llc_shared_map);
-
- if (current_cpu_data.x86_max_cores == 1) {
- cpu_core_map[cpu] = cpu_sibling_map[cpu];
- c[cpu].booted_cores = 1;
- return;
- }
-
- for_each_cpu_mask(i, cpu_sibling_setup_map) {
- if (cpu_llc_id[cpu] != BAD_APICID &&
- cpu_llc_id[cpu] == cpu_llc_id[i]) {
- cpu_set(i, c[cpu].llc_shared_map);
- cpu_set(cpu, c[i].llc_shared_map);
- }
- if (c[cpu].phys_proc_id == c[i].phys_proc_id) {
- cpu_set(i, cpu_core_map[cpu]);
- cpu_set(cpu, cpu_core_map[i]);
- /*
- * Does this new cpu bringup a new core?
- */
- if (cpus_weight(cpu_sibling_map[cpu]) == 1) {
- /*
- * for each core in package, increment
- * the booted_cores for this new cpu
- */
- if (first_cpu(cpu_sibling_map[i]) == i)
- c[cpu].booted_cores++;
- /*
- * increment the core count for all
- * the other cpus in this package
- */
- if (i != cpu)
- c[i].booted_cores++;
- } else if (i != cpu && !c[cpu].booted_cores)
- c[cpu].booted_cores = c[i].booted_cores;
- }
- }
-}
-
-/*
- * Setup code on secondary processor (after comming out of the trampoline)
- */
-void __cpuinit start_secondary(void)
-{
- /*
- * Dont put anything before smp_callin(), SMP
- * booting is too fragile that we want to limit the
- * things done here to the most necessary things.
- */
- cpu_init();
- preempt_disable();
- smp_callin();
-
- /* otherwise gcc will move up the smp_processor_id before the cpu_init */
- barrier();
-
- /*
- * Check TSC sync first:
- */
- check_tsc_sync_target();
-
- Dprintk("cpu %d: setting up apic clock\n", smp_processor_id());
- setup_secondary_APIC_clock();
-
- Dprintk("cpu %d: enabling apic timer\n", smp_processor_id());
-
- if (nmi_watchdog == NMI_IO_APIC) {
- disable_8259A_irq(0);
- enable_NMI_through_LVT0(NULL);
- enable_8259A_irq(0);
- }
-
- enable_APIC_timer();
-
- /*
- * The sibling maps must be set before turing the online map on for
- * this cpu
- */
- set_cpu_sibling_map(smp_processor_id());
-
- /*
- * We need to hold call_lock, so there is no inconsistency
- * between the time smp_call_function() determines number of
- * IPI receipients, and the time when the determination is made
- * for which cpus receive the IPI in genapic_flat.c. Holding this
- * lock helps us to not include this cpu in a currently in progress
- * smp_call_function().
- */
- lock_ipi_call_lock();
- spin_lock(&vector_lock);
-
- /* Setup the per cpu irq handling data structures */
- __setup_vector_irq(smp_processor_id());
- /*
- * Allow the master to continue.
- */
- cpu_set(smp_processor_id(), cpu_online_map);
- per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
- spin_unlock(&vector_lock);
-
- unlock_ipi_call_lock();
-
- cpu_idle();
-}
-
-extern volatile unsigned long init_rsp;
-extern void (*initial_code)(void);
-
-#ifdef APIC_DEBUG
-static void inquire_remote_apic(int apicid)
-{
- unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
- char *names[] = { "ID", "VERSION", "SPIV" };
- int timeout;
- unsigned int status;
-
- printk(KERN_INFO "Inquiring remote APIC #%d...\n", apicid);
-
- for (i = 0; i < sizeof(regs) / sizeof(*regs); i++) {
- printk("... APIC #%d %s: ", apicid, names[i]);
-
- /*
- * Wait for idle.
- */
- status = safe_apic_wait_icr_idle();
- if (status)
- printk("a previous APIC delivery may have failed\n");
-
- apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(apicid));
- apic_write(APIC_ICR, APIC_DM_REMRD | regs[i]);
-
- timeout = 0;
- do {
- udelay(100);
- status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
- } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
-
- switch (status) {
- case APIC_ICR_RR_VALID:
- status = apic_read(APIC_RRR);
- printk("%08x\n", status);
- break;
- default:
- printk("failed\n");
- }
- }
-}
-#endif
-
-/*
- * Kick the secondary to wake up.
- */
-static int __cpuinit wakeup_secondary_via_INIT(int phys_apicid, unsigned int start_rip)
-{
- unsigned long send_status, accept_status = 0;
- int maxlvt, num_starts, j;
-
- Dprintk("Asserting INIT.\n");
-
- /*
- * Turn INIT on target chip
- */
- apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
-
- /*
- * Send IPI
- */
- apic_write(APIC_ICR, APIC_INT_LEVELTRIG | APIC_INT_ASSERT
- | APIC_DM_INIT);
-
- Dprintk("Waiting for send to finish...\n");
- send_status = safe_apic_wait_icr_idle();
-
- mdelay(10);
-
- Dprintk("Deasserting INIT.\n");
-
- /* Target chip */
- apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
-
- /* Send IPI */
- apic_write(APIC_ICR, APIC_INT_LEVELTRIG | APIC_DM_INIT);
-
- Dprintk("Waiting for send to finish...\n");
- send_status = safe_apic_wait_icr_idle();
-
- mb();
- atomic_set(&init_deasserted, 1);
-
- num_starts = 2;
-
- /*
- * Run STARTUP IPI loop.
- */
- Dprintk("#startup loops: %d.\n", num_starts);
-
- maxlvt = get_maxlvt();
-
- for (j = 1; j <= num_starts; j++) {
- Dprintk("Sending STARTUP #%d.\n",j);
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- Dprintk("After apic_write.\n");
-
- /*
- * STARTUP IPI
- */
-
- /* Target chip */
- apic_write(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
-
- /* Boot on the stack */
- /* Kick the second */
- apic_write(APIC_ICR, APIC_DM_STARTUP | (start_rip >> 12));
-
- /*
- * Give the other CPU some time to accept the IPI.
- */
- udelay(300);
-
- Dprintk("Startup point 1.\n");
-
- Dprintk("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);
- /*
- * Due to the Pentium erratum 3AP.
- */
- if (maxlvt > 3) {
- apic_write(APIC_ESR, 0);
- }
- accept_status = (apic_read(APIC_ESR) & 0xEF);
- if (send_status || accept_status)
- break;
- }
- Dprintk("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);
-}
-
-struct create_idle {
- struct work_struct work;
- struct task_struct *idle;
- struct completion done;
- int cpu;
-};
-
-void do_fork_idle(struct work_struct *work)
-{
- struct create_idle *c_idle =
- container_of(work, struct create_idle, work);
-
- c_idle->idle = fork_idle(c_idle->cpu);
- complete(&c_idle->done);
-}
-
-/*
- * Boot one CPU.
- */
-static int __cpuinit do_boot_cpu(int cpu, int apicid)
-{
- unsigned long boot_error;
- int timeout;
- unsigned long start_rip;
- struct create_idle c_idle = {
- .work = __WORK_INITIALIZER(c_idle.work, do_fork_idle),
- .cpu = cpu,
- .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
- };
-
- /* allocate memory for gdts of secondary cpus. Hotplug is considered */
- if (!cpu_gdt_descr[cpu].address &&
- !(cpu_gdt_descr[cpu].address = get_zeroed_page(GFP_KERNEL))) {
- printk(KERN_ERR "Failed to allocate GDT for CPU %d\n", cpu);
- return -1;
- }
-
- /* Allocate node local memory for AP pdas */
- if (cpu_pda(cpu) == &boot_cpu_pda[cpu]) {
- struct x8664_pda *newpda, *pda;
- int node = cpu_to_node(cpu);
- pda = cpu_pda(cpu);
- newpda = kmalloc_node(sizeof (struct x8664_pda), GFP_ATOMIC,
- node);
- if (newpda) {
- memcpy(newpda, pda, sizeof (struct x8664_pda));
- cpu_pda(cpu) = newpda;
- } else
- printk(KERN_ERR
- "Could not allocate node local PDA for CPU %d on node %d\n",
- cpu, node);
- }
-
- alternatives_smp_switch(1);
-
- c_idle.idle = get_idle_for_cpu(cpu);
-
- if (c_idle.idle) {
- c_idle.idle->thread.rsp = (unsigned long) (((struct pt_regs *)
- (THREAD_SIZE + task_stack_page(c_idle.idle))) - 1);
- init_idle(c_idle.idle, cpu);
- goto do_rest;
- }
-
- /*
- * During cold boot process, keventd thread is not spun up yet.
- * When we do cpu hot-add, we create idle threads on the fly, we should
- * not acquire any attributes from the calling context. Hence the clean
- * way to create kernel_threads() is to do that from keventd().
- * We do the current_is_keventd() due to the fact that ACPI notifier
- * was also queuing to keventd() and when the caller is already running
- * in context of keventd(), we would end up with locking up the keventd
- * thread.
- */
- if (!keventd_up() || current_is_keventd())
- c_idle.work.func(&c_idle.work);
- else {
- schedule_work(&c_idle.work);
- wait_for_completion(&c_idle.done);
- }
-
- if (IS_ERR(c_idle.idle)) {
- printk("failed fork for CPU %d\n", cpu);
- return PTR_ERR(c_idle.idle);
- }
-
- set_idle_for_cpu(cpu, c_idle.idle);
-
-do_rest:
-
- cpu_pda(cpu)->pcurrent = c_idle.idle;
-
- start_rip = setup_trampoline();
-
- init_rsp = c_idle.idle->thread.rsp;
- per_cpu(init_tss,cpu).rsp0 = init_rsp;
- initial_code = start_secondary;
- clear_tsk_thread_flag(c_idle.idle, TIF_FORK);
-
- printk(KERN_INFO "Booting processor %d/%d APIC 0x%x\n", cpu,
- cpus_weight(cpu_present_map),
- apicid);
-
- /*
- * This grunge runs the startup process for
- * the targeted processor.
- */
-
- atomic_set(&init_deasserted, 0);
-
- Dprintk("Setting warm reset code and vector.\n");
-
- CMOS_WRITE(0xa, 0xf);
- local_flush_tlb();
- Dprintk("1.\n");
- *((volatile unsigned short *) phys_to_virt(0x469)) = start_rip >> 4;
- Dprintk("2.\n");
- *((volatile unsigned short *) phys_to_virt(0x467)) = start_rip & 0xf;
- Dprintk("3.\n");
-
- /*
- * Be paranoid about clearing APIC errors.
- */
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
-
- /*
- * Status is now clean
- */
- boot_error = 0;
-
- /*
- * Starting actual IPI sequence...
- */
- boot_error = wakeup_secondary_via_INIT(apicid, start_rip);
-
- if (!boot_error) {
- /*
- * allow APs to start initializing.
- */
- Dprintk("Before Callout %d.\n", cpu);
- cpu_set(cpu, cpu_callout_map);
- Dprintk("After Callout %d.\n", cpu);
-
- /*
- * Wait 5s total for a response
- */
- for (timeout = 0; timeout < 50000; timeout++) {
- if (cpu_isset(cpu, cpu_callin_map))
- break; /* It has booted */
- udelay(100);
- }
-
- if (cpu_isset(cpu, cpu_callin_map)) {
- /* number CPUs logically, starting from 1 (BSP is 0) */
- Dprintk("CPU has booted.\n");
- } else {
- boot_error = 1;
- if (*((volatile unsigned char *)phys_to_virt(SMP_TRAMPOLINE_BASE))
- == 0xA5)
- /* trampoline started but...? */
- printk("Stuck ??\n");
- else
- /* trampoline code not run */
- printk("Not responding.\n");
-#ifdef APIC_DEBUG
- inquire_remote_apic(apicid);
-#endif
- }
- }
- if (boot_error) {
- cpu_clear(cpu, cpu_callout_map); /* was set here (do_boot_cpu()) */
- clear_bit(cpu, &cpu_initialized); /* was set by cpu_init() */
- clear_node_cpumask(cpu); /* was set by numa_add_cpu */
- cpu_clear(cpu, cpu_present_map);
- cpu_clear(cpu, cpu_possible_map);
- x86_cpu_to_apicid[cpu] = BAD_APICID;
- x86_cpu_to_log_apicid[cpu] = BAD_APICID;
- return -EIO;
- }
-
- return 0;
-}
-
-cycles_t cacheflush_time;
-unsigned long cache_decay_ticks;
-
-/*
- * Cleanup possible dangling ends...
- */
-static __cpuinit void smp_cleanup_boot(void)
-{
- /*
- * Paranoid: Set warm reset code and vector here back
- * to default values.
- */
- CMOS_WRITE(0, 0xf);
-
- /*
- * Reset trampoline flag
- */
- *((volatile int *) phys_to_virt(0x467)) = 0;
-}
-
-/*
- * 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)
-{
- cpu_present_map = cpumask_of_cpu(0);
- cpu_possible_map = cpumask_of_cpu(0);
- if (smp_found_config)
- phys_cpu_present_map = physid_mask_of_physid(boot_cpu_id);
- else
- phys_cpu_present_map = physid_mask_of_physid(0);
- cpu_set(0, cpu_sibling_map[0]);
- cpu_set(0, cpu_core_map[0]);
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-int additional_cpus __initdata = -1;
-
-/*
- * cpu_possible_map 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_map 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 additional_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;
- int possible;
-
- if (additional_cpus == -1) {
- if (disabled_cpus > 0)
- additional_cpus = disabled_cpus;
- else
- additional_cpus = 0;
- }
- possible = num_processors + additional_cpus;
- if (possible > NR_CPUS)
- possible = NR_CPUS;
-
- 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++)
- cpu_set(i, cpu_possible_map);
-}
-#endif
-
-/*
- * Various sanity checks.
- */
-static int __init smp_sanity_check(unsigned max_cpus)
-{
- if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
- printk("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) {
- 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 (!physid_isset(boot_cpu_id, phys_cpu_present_map)) {
- printk(KERN_NOTICE "weird, boot CPU (#%d) not listed by the BIOS.\n",
- boot_cpu_id);
- physid_set(hard_smp_processor_id(), phys_cpu_present_map);
- }
-
- /*
- * If we couldn't find a local APIC, then get out of here now!
- */
- if (!cpu_has_apic) {
- printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
- boot_cpu_id);
- printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");
- nr_ioapics = 0;
- return -1;
- }
-
- /*
- * If SMP should be disabled, then really disable it!
- */
- if (!max_cpus) {
- printk(KERN_INFO "SMP mode deactivated, forcing use of dummy APIC emulation.\n");
- nr_ioapics = 0;
- return -1;
- }
-
- return 0;
-}
-
-/*
- * 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 smp_prepare_cpus(unsigned int max_cpus)
-{
- nmi_watchdog_default();
- current_cpu_data = boot_cpu_data;
- current_thread_info()->cpu = 0; /* needed? */
- set_cpu_sibling_map(0);
-
- if (smp_sanity_check(max_cpus) < 0) {
- printk(KERN_INFO "SMP disabled\n");
- disable_smp();
- return;
- }
-
-
- /*
- * Switch from PIC to APIC mode.
- */
- setup_local_APIC();
-
- if (GET_APIC_ID(apic_read(APIC_ID)) != boot_cpu_id) {
- panic("Boot APIC ID in local APIC unexpected (%d vs %d)",
- GET_APIC_ID(apic_read(APIC_ID)), boot_cpu_id);
- /* Or can we switch back to PIC here? */
- }
-
- /*
- * Now start the IO-APICs
- */
- if (!skip_ioapic_setup && nr_ioapics)
- setup_IO_APIC();
- else
- nr_ioapics = 0;
-
- /*
- * Set up local APIC timer on boot CPU.
- */
-
- setup_boot_APIC_clock();
-}
-
-/*
- * Early setup to make printk work.
- */
-void __init smp_prepare_boot_cpu(void)
-{
- int me = smp_processor_id();
- cpu_set(me, cpu_online_map);
- cpu_set(me, cpu_callout_map);
- per_cpu(cpu_state, me) = CPU_ONLINE;
-}
-
-/*
- * Entry point to boot a CPU.
- */
-int __cpuinit __cpu_up(unsigned int cpu)
-{
- int apicid = cpu_present_to_apicid(cpu);
- unsigned long flags;
- int err;
-
- WARN_ON(irqs_disabled());
-
- Dprintk("++++++++++++++++++++=_---CPU UP %u\n", cpu);
-
- if (apicid == BAD_APICID || apicid == boot_cpu_id ||
- !physid_isset(apicid, phys_cpu_present_map)) {
- printk("__cpu_up: bad cpu %d\n", cpu);
- return -EINVAL;
- }
-
- /*
- * Already booted CPU?
- */
- if (cpu_isset(cpu, cpu_callin_map)) {
- Dprintk("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;
- /* Boot it! */
- err = do_boot_cpu(cpu, apicid);
- if (err < 0) {
- Dprintk("do_boot_cpu failed %d\n", err);
- return err;
- }
-
- /* Unleash the CPU! */
- Dprintk("waiting for cpu %d\n", cpu);
-
- /*
- * Make sure and check TSC sync:
- */
- local_irq_save(flags);
- check_tsc_sync_source(cpu);
- local_irq_restore(flags);
-
- while (!cpu_isset(cpu, cpu_online_map))
- cpu_relax();
- err = 0;
-
- return err;
-}
-
-/*
- * Finish the SMP boot.
- */
-void __init smp_cpus_done(unsigned int max_cpus)
-{
- smp_cleanup_boot();
- setup_ioapic_dest();
- check_nmi_watchdog();
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-
-static void remove_siblinginfo(int cpu)
-{
- int sibling;
- struct cpuinfo_x86 *c = cpu_data;
-
- for_each_cpu_mask(sibling, cpu_core_map[cpu]) {
- cpu_clear(cpu, cpu_core_map[sibling]);
- /*
- * last thread sibling in this cpu core going down
- */
- if (cpus_weight(cpu_sibling_map[cpu]) == 1)
- c[sibling].booted_cores--;
- }
-
- for_each_cpu_mask(sibling, cpu_sibling_map[cpu])
- cpu_clear(cpu, cpu_sibling_map[sibling]);
- cpus_clear(cpu_sibling_map[cpu]);
- cpus_clear(cpu_core_map[cpu]);
- c[cpu].phys_proc_id = 0;
- c[cpu].cpu_core_id = 0;
- cpu_clear(cpu, cpu_sibling_setup_map);
-}
-
-void remove_cpu_from_maps(void)
-{
- int cpu = smp_processor_id();
-
- cpu_clear(cpu, cpu_callout_map);
- cpu_clear(cpu, cpu_callin_map);
- clear_bit(cpu, &cpu_initialized); /* was set by cpu_init() */
- clear_node_cpumask(cpu);
-}
-
-int __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;
-
- if (nmi_watchdog == NMI_LOCAL_APIC)
- stop_apic_nmi_watchdog(NULL);
- clear_local_APIC();
-
- /*
- * HACK:
- * Allow any queued timer interrupts to get serviced
- * This is only a temporary solution until we cleanup
- * fixup_irqs as we do for IA64.
- */
- local_irq_enable();
- mdelay(1);
-
- local_irq_disable();
- remove_siblinginfo(cpu);
-
- spin_lock(&vector_lock);
- /* It's now safe to remove this processor from the online map */
- cpu_clear(cpu, cpu_online_map);
- spin_unlock(&vector_lock);
- remove_cpu_from_maps();
- fixup_irqs(cpu_online_map);
- return 0;
-}
-
-void __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) {
- printk ("CPU %d is now offline\n", cpu);
- if (1 == num_online_cpus())
- alternatives_smp_switch(0);
- return;
- }
- msleep(100);
- }
- printk(KERN_ERR "CPU %u didn't die...\n", cpu);
-}
-
-static __init int setup_additional_cpus(char *s)
-{
- return s && get_option(&s, &additional_cpus) ? 0 : -EINVAL;
-}
-early_param("additional_cpus", setup_additional_cpus);
-
-#else /* ... !CONFIG_HOTPLUG_CPU */
-
-int __cpu_disable(void)
-{
- return -ENOSYS;
-}
-
-void __cpu_die(unsigned int cpu)
-{
- /* We said "no" in __cpu_disable */
- BUG();
-}
-#endif /* CONFIG_HOTPLUG_CPU */