2 * x86 SMP booting functions
4 * (c) 1995 Alan Cox, Building #3 <alan@redhat.com>
5 * (c) 1998, 1999, 2000 Ingo Molnar <mingo@redhat.com>
7 * Much of the core SMP work is based on previous work by Thomas Radke, to
8 * whom a great many thanks are extended.
10 * Thanks to Intel for making available several different Pentium,
11 * Pentium Pro and Pentium-II/Xeon MP machines.
12 * Original development of Linux SMP code supported by Caldera.
14 * This code is released under the GNU General Public License version 2 or
18 * Felix Koop : NR_CPUS used properly
19 * Jose Renau : Handle single CPU case.
20 * Alan Cox : By repeated request 8) - Total BogoMIPS report.
21 * Greg Wright : Fix for kernel stacks panic.
22 * Erich Boleyn : MP v1.4 and additional changes.
23 * Matthias Sattler : Changes for 2.1 kernel map.
24 * Michel Lespinasse : Changes for 2.1 kernel map.
25 * Michael Chastain : Change trampoline.S to gnu as.
26 * Alan Cox : Dumb bug: 'B' step PPro's are fine
27 * Ingo Molnar : Added APIC timers, based on code
29 * Ingo Molnar : various cleanups and rewrites
30 * Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug.
31 * Maciej W. Rozycki : Bits for genuine 82489DX APICs
32 * Martin J. Bligh : Added support for multi-quad systems
33 * Dave Jones : Report invalid combinations of Athlon CPUs.
34 * Rusty Russell : Hacked into shape for new "hotplug" boot process. */
36 #include <linux/module.h>
37 #include <linux/init.h>
38 #include <linux/kernel.h>
41 #include <linux/sched.h>
42 #include <linux/kernel_stat.h>
43 #include <linux/bootmem.h>
44 #include <linux/notifier.h>
45 #include <linux/cpu.h>
46 #include <linux/percpu.h>
47 #include <linux/nmi.h>
49 #include <linux/delay.h>
50 #include <linux/mc146818rtc.h>
51 #include <asm/tlbflush.h>
53 #include <asm/arch_hooks.h>
56 #include <mach_apic.h>
57 #include <mach_wakecpu.h>
58 #include <smpboot_hooks.h>
62 /* which logical CPU number maps to which CPU (physical APIC ID) */
63 u16 x86_cpu_to_apicid_init[NR_CPUS] __initdata =
64 { [0 ... NR_CPUS-1] = BAD_APICID };
65 void *x86_cpu_to_apicid_early_ptr;
66 DEFINE_PER_CPU(u16, x86_cpu_to_apicid) = BAD_APICID;
67 EXPORT_PER_CPU_SYMBOL(x86_cpu_to_apicid);
69 u16 x86_bios_cpu_apicid_init[NR_CPUS] __initdata
70 = { [0 ... NR_CPUS-1] = BAD_APICID };
71 void *x86_bios_cpu_apicid_early_ptr;
72 DEFINE_PER_CPU(u16, x86_bios_cpu_apicid) = BAD_APICID;
73 EXPORT_PER_CPU_SYMBOL(x86_bios_cpu_apicid);
75 u8 apicid_2_node[MAX_APICID];
77 static void map_cpu_to_logical_apicid(void);
79 /* State of each CPU. */
80 DEFINE_PER_CPU(int, cpu_state) = { 0 };
82 /* Store all idle threads, this can be reused instead of creating
83 * a new thread. Also avoids complicated thread destroy functionality
86 #ifdef CONFIG_HOTPLUG_CPU
88 * Needed only for CONFIG_HOTPLUG_CPU because __cpuinitdata is
89 * removed after init for !CONFIG_HOTPLUG_CPU.
91 static DEFINE_PER_CPU(struct task_struct *, idle_thread_array);
92 #define get_idle_for_cpu(x) (per_cpu(idle_thread_array, x))
93 #define set_idle_for_cpu(x, p) (per_cpu(idle_thread_array, x) = (p))
95 struct task_struct *idle_thread_array[NR_CPUS] __cpuinitdata ;
96 #define get_idle_for_cpu(x) (idle_thread_array[(x)])
97 #define set_idle_for_cpu(x, p) (idle_thread_array[(x)] = (p))
100 static atomic_t init_deasserted;
102 static void __cpuinit smp_callin(void)
105 unsigned long timeout;
108 * If waken up by an INIT in an 82489DX configuration
109 * we may get here before an INIT-deassert IPI reaches
110 * our local APIC. We have to wait for the IPI or we'll
111 * lock up on an APIC access.
113 wait_for_init_deassert(&init_deasserted);
116 * (This works even if the APIC is not enabled.)
118 phys_id = GET_APIC_ID(apic_read(APIC_ID));
119 cpuid = smp_processor_id();
120 if (cpu_isset(cpuid, cpu_callin_map)) {
121 printk("huh, phys CPU#%d, CPU#%d already present??\n",
125 Dprintk("CPU#%d (phys ID: %d) waiting for CALLOUT\n", cpuid, phys_id);
128 * STARTUP IPIs are fragile beasts as they might sometimes
129 * trigger some glue motherboard logic. Complete APIC bus
130 * silence for 1 second, this overestimates the time the
131 * boot CPU is spending to send the up to 2 STARTUP IPIs
132 * by a factor of two. This should be enough.
136 * Waiting 2s total for startup (udelay is not yet working)
138 timeout = jiffies + 2*HZ;
139 while (time_before(jiffies, timeout)) {
141 * Has the boot CPU finished it's STARTUP sequence?
143 if (cpu_isset(cpuid, cpu_callout_map))
148 if (!time_before(jiffies, timeout)) {
149 printk("BUG: CPU%d started up but did not get a callout!\n",
155 * the boot CPU has finished the init stage and is spinning
156 * on callin_map until we finish. We are free to set up this
157 * CPU, first the APIC. (this is probably redundant on most
161 Dprintk("CALLIN, before setup_local_APIC().\n");
162 smp_callin_clear_local_apic();
164 end_local_APIC_setup();
165 map_cpu_to_logical_apicid();
171 Dprintk("Stack at about %p\n",&cpuid);
174 * Save our processor parameters
176 smp_store_cpu_info(cpuid);
179 * Allow the master to continue.
181 cpu_set(cpuid, cpu_callin_map);
185 * Activate a secondary processor.
187 static void __cpuinit start_secondary(void *unused)
190 * Don't put *anything* before cpu_init(), SMP booting is too
191 * fragile that we want to limit the things done here to the
192 * most necessary things.
201 /* otherwise gcc will move up smp_processor_id before the cpu_init */
204 * Check TSC synchronization with the BP:
206 check_tsc_sync_target();
208 if (nmi_watchdog == NMI_IO_APIC) {
209 disable_8259A_irq(0);
210 enable_NMI_through_LVT0();
214 /* This must be done before setting cpu_online_map */
215 set_cpu_sibling_map(raw_smp_processor_id());
219 * We need to hold call_lock, so there is no inconsistency
220 * between the time smp_call_function() determines number of
221 * IPI recipients, and the time when the determination is made
222 * for which cpus receive the IPI. Holding this
223 * lock helps us to not include this cpu in a currently in progress
224 * smp_call_function().
226 lock_ipi_call_lock();
227 cpu_set(smp_processor_id(), cpu_online_map);
228 unlock_ipi_call_lock();
229 per_cpu(cpu_state, smp_processor_id()) = CPU_ONLINE;
231 setup_secondary_clock();
238 * Everything has been set up for the secondary
239 * CPUs - they just need to reload everything
240 * from the task structure
241 * This function must not return.
243 void __devinit initialize_secondary(void)
246 * We don't actually need to load the full TSS,
247 * basically just the stack pointer and the ip.
254 :"m" (current->thread.sp),"m" (current->thread.ip));
257 /* Static state in head.S used to set up a CPU */
265 /* which logical CPUs are on which nodes */
266 cpumask_t node_to_cpumask_map[MAX_NUMNODES] __read_mostly =
267 { [0 ... MAX_NUMNODES-1] = CPU_MASK_NONE };
268 EXPORT_SYMBOL(node_to_cpumask_map);
269 /* which node each logical CPU is on */
270 int cpu_to_node_map[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = 0 };
271 EXPORT_SYMBOL(cpu_to_node_map);
273 /* set up a mapping between cpu and node. */
274 static inline void map_cpu_to_node(int cpu, int node)
276 printk("Mapping cpu %d to node %d\n", cpu, node);
277 cpu_set(cpu, node_to_cpumask_map[node]);
278 cpu_to_node_map[cpu] = node;
281 /* undo a mapping between cpu and node. */
282 static inline void unmap_cpu_to_node(int cpu)
286 printk("Unmapping cpu %d from all nodes\n", cpu);
287 for (node = 0; node < MAX_NUMNODES; node ++)
288 cpu_clear(cpu, node_to_cpumask_map[node]);
289 cpu_to_node_map[cpu] = 0;
291 #else /* !CONFIG_NUMA */
293 #define map_cpu_to_node(cpu, node) ({})
294 #define unmap_cpu_to_node(cpu) ({})
296 #endif /* CONFIG_NUMA */
298 u8 cpu_2_logical_apicid[NR_CPUS] __read_mostly = { [0 ... NR_CPUS-1] = BAD_APICID };
300 static void map_cpu_to_logical_apicid(void)
302 int cpu = smp_processor_id();
303 int apicid = logical_smp_processor_id();
304 int node = apicid_to_node(apicid);
306 if (!node_online(node))
307 node = first_online_node;
309 cpu_2_logical_apicid[cpu] = apicid;
310 map_cpu_to_node(cpu, node);
313 static void unmap_cpu_to_logical_apicid(int cpu)
315 cpu_2_logical_apicid[cpu] = BAD_APICID;
316 unmap_cpu_to_node(cpu);
319 static inline void __inquire_remote_apic(int apicid)
321 unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
322 char *names[] = { "ID", "VERSION", "SPIV" };
326 printk(KERN_INFO "Inquiring remote APIC #%d...\n", apicid);
328 for (i = 0; i < ARRAY_SIZE(regs); i++) {
329 printk(KERN_INFO "... APIC #%d %s: ", apicid, names[i]);
334 status = safe_apic_wait_icr_idle();
337 "a previous APIC delivery may have failed\n");
339 apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(apicid));
340 apic_write_around(APIC_ICR, APIC_DM_REMRD | regs[i]);
345 status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
346 } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
349 case APIC_ICR_RR_VALID:
350 status = apic_read(APIC_RRR);
351 printk(KERN_CONT "%08x\n", status);
354 printk(KERN_CONT "failed\n");
359 #ifdef WAKE_SECONDARY_VIA_NMI
361 * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
362 * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
363 * won't ... remember to clear down the APIC, etc later.
366 wakeup_secondary_cpu(int logical_apicid, unsigned long start_eip)
368 unsigned long send_status, accept_status = 0;
372 apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(logical_apicid));
374 /* Boot on the stack */
375 /* Kick the second */
376 apic_write_around(APIC_ICR, APIC_DM_NMI | APIC_DEST_LOGICAL);
378 Dprintk("Waiting for send to finish...\n");
379 send_status = safe_apic_wait_icr_idle();
382 * Give the other CPU some time to accept the IPI.
386 * Due to the Pentium erratum 3AP.
388 maxlvt = lapic_get_maxlvt();
390 apic_read_around(APIC_SPIV);
391 apic_write(APIC_ESR, 0);
393 accept_status = (apic_read(APIC_ESR) & 0xEF);
394 Dprintk("NMI sent.\n");
397 printk("APIC never delivered???\n");
399 printk("APIC delivery error (%lx).\n", accept_status);
401 return (send_status | accept_status);
403 #endif /* WAKE_SECONDARY_VIA_NMI */
405 #ifdef WAKE_SECONDARY_VIA_INIT
407 wakeup_secondary_cpu(int phys_apicid, unsigned long start_eip)
409 unsigned long send_status, accept_status = 0;
410 int maxlvt, num_starts, j;
413 * Be paranoid about clearing APIC errors.
415 if (APIC_INTEGRATED(apic_version[phys_apicid])) {
416 apic_read_around(APIC_SPIV);
417 apic_write(APIC_ESR, 0);
421 Dprintk("Asserting INIT.\n");
424 * Turn INIT on target chip
426 apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
431 apic_write_around(APIC_ICR, APIC_INT_LEVELTRIG | APIC_INT_ASSERT
434 Dprintk("Waiting for send to finish...\n");
435 send_status = safe_apic_wait_icr_idle();
439 Dprintk("Deasserting INIT.\n");
442 apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
445 apic_write_around(APIC_ICR, APIC_INT_LEVELTRIG | APIC_DM_INIT);
447 Dprintk("Waiting for send to finish...\n");
448 send_status = safe_apic_wait_icr_idle();
451 atomic_set(&init_deasserted, 1);
454 * Should we send STARTUP IPIs ?
456 * Determine this based on the APIC version.
457 * If we don't have an integrated APIC, don't send the STARTUP IPIs.
459 if (APIC_INTEGRATED(apic_version[phys_apicid]))
465 * Paravirt / VMI wants a startup IPI hook here to set up the
466 * target processor state.
468 startup_ipi_hook(phys_apicid, (unsigned long) start_secondary,
469 (unsigned long) stack_start.sp);
472 * Run STARTUP IPI loop.
474 Dprintk("#startup loops: %d.\n", num_starts);
476 maxlvt = lapic_get_maxlvt();
478 for (j = 1; j <= num_starts; j++) {
479 Dprintk("Sending STARTUP #%d.\n",j);
480 apic_read_around(APIC_SPIV);
481 apic_write(APIC_ESR, 0);
483 Dprintk("After apic_write.\n");
490 apic_write_around(APIC_ICR2, SET_APIC_DEST_FIELD(phys_apicid));
492 /* Boot on the stack */
493 /* Kick the second */
494 apic_write_around(APIC_ICR, APIC_DM_STARTUP
495 | (start_eip >> 12));
498 * Give the other CPU some time to accept the IPI.
502 Dprintk("Startup point 1.\n");
504 Dprintk("Waiting for send to finish...\n");
505 send_status = safe_apic_wait_icr_idle();
508 * Give the other CPU some time to accept the IPI.
512 * Due to the Pentium erratum 3AP.
515 apic_read_around(APIC_SPIV);
516 apic_write(APIC_ESR, 0);
518 accept_status = (apic_read(APIC_ESR) & 0xEF);
519 if (send_status || accept_status)
522 Dprintk("After Startup.\n");
525 printk("APIC never delivered???\n");
527 printk("APIC delivery error (%lx).\n", accept_status);
529 return (send_status | accept_status);
531 #endif /* WAKE_SECONDARY_VIA_INIT */
533 extern cpumask_t cpu_initialized;
536 struct work_struct work;
537 struct task_struct *idle;
538 struct completion done;
542 static void __cpuinit do_fork_idle(struct work_struct *work)
544 struct create_idle *c_idle =
545 container_of(work, struct create_idle, work);
547 c_idle->idle = fork_idle(c_idle->cpu);
548 complete(&c_idle->done);
550 static int __cpuinit do_boot_cpu(int apicid, int cpu)
552 * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
553 * (ie clustered apic addressing mode), this is a LOGICAL apic ID.
554 * Returns zero if CPU booted OK, else error code from wakeup_secondary_cpu.
557 unsigned long boot_error;
559 unsigned long start_eip;
560 unsigned short nmi_high = 0, nmi_low = 0;
561 struct create_idle c_idle = {
563 .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
565 INIT_WORK(&c_idle.work, do_fork_idle);
568 * Save current MTRR state in case it was changed since early boot
569 * (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync:
573 c_idle.idle = get_idle_for_cpu(cpu);
576 * We can't use kernel_thread since we must avoid to
577 * reschedule the child.
580 c_idle.idle->thread.sp = (unsigned long) (((struct pt_regs *)
581 (THREAD_SIZE + task_stack_page(c_idle.idle))) - 1);
582 init_idle(c_idle.idle, cpu);
586 if (!keventd_up() || current_is_keventd())
587 c_idle.work.func(&c_idle.work);
589 schedule_work(&c_idle.work);
590 wait_for_completion(&c_idle.done);
593 if (IS_ERR(c_idle.idle)) {
594 printk(KERN_ERR "failed fork for CPU %d\n", cpu);
595 return PTR_ERR(c_idle.idle);
598 set_idle_for_cpu(cpu, c_idle.idle);
600 per_cpu(current_task, cpu) = c_idle.idle;
602 early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
604 c_idle.idle->thread.ip = (unsigned long) start_secondary;
605 /* start_eip had better be page-aligned! */
606 start_eip = setup_trampoline();
608 alternatives_smp_switch(1);
610 /* So we see what's up */
611 printk("Booting processor %d/%d ip %lx\n", cpu, apicid, start_eip);
612 /* Stack for startup_32 can be just as for start_secondary onwards */
613 stack_start.sp = (void *) c_idle.idle->thread.sp;
618 * This grunge runs the startup process for
619 * the targeted processor.
622 atomic_set(&init_deasserted, 0);
624 Dprintk("Setting warm reset code and vector.\n");
626 store_NMI_vector(&nmi_high, &nmi_low);
628 smpboot_setup_warm_reset_vector(start_eip);
631 * Starting actual IPI sequence...
633 boot_error = wakeup_secondary_cpu(apicid, start_eip);
637 * allow APs to start initializing.
639 Dprintk("Before Callout %d.\n", cpu);
640 cpu_set(cpu, cpu_callout_map);
641 Dprintk("After Callout %d.\n", cpu);
644 * Wait 5s total for a response
646 for (timeout = 0; timeout < 50000; timeout++) {
647 if (cpu_isset(cpu, cpu_callin_map))
648 break; /* It has booted */
652 if (cpu_isset(cpu, cpu_callin_map)) {
653 /* number CPUs logically, starting from 1 (BSP is 0) */
655 printk("CPU%d: ", cpu);
656 print_cpu_info(&cpu_data(cpu));
657 Dprintk("CPU has booted.\n");
660 if (*((volatile unsigned char *)trampoline_base)
662 /* trampoline started but...? */
663 printk("Stuck ??\n");
665 /* trampoline code not run */
666 printk("Not responding.\n");
667 inquire_remote_apic(apicid);
672 /* Try to put things back the way they were before ... */
673 unmap_cpu_to_logical_apicid(cpu);
674 cpu_clear(cpu, cpu_callout_map); /* was set here (do_boot_cpu()) */
675 cpu_clear(cpu, cpu_initialized); /* was set by cpu_init() */
676 cpu_clear(cpu, cpu_possible_map);
677 per_cpu(x86_cpu_to_apicid, cpu) = BAD_APICID;
680 /* mark "stuck" area as not stuck */
681 *((volatile unsigned long *)trampoline_base) = 0;
686 #ifdef CONFIG_HOTPLUG_CPU
687 void cpu_exit_clear(void)
689 int cpu = raw_smp_processor_id();
696 cpu_clear(cpu, cpu_callout_map);
697 cpu_clear(cpu, cpu_callin_map);
699 unmap_cpu_to_logical_apicid(cpu);
703 static void __cpuinit __smp_prepare_cpu(int cpu)
707 apicid = per_cpu(x86_cpu_to_apicid, cpu);
709 /* init low mem mapping */
710 clone_pgd_range(swapper_pg_dir, swapper_pg_dir + USER_PGD_PTRS,
711 min_t(unsigned long, KERNEL_PGD_PTRS, USER_PGD_PTRS));
714 do_boot_cpu(apicid, cpu);
717 static int boot_cpu_logical_apicid;
718 /* Where the IO area was mapped on multiquad, always 0 otherwise */
720 #ifdef CONFIG_X86_NUMAQ
721 EXPORT_SYMBOL(xquad_portio);
724 static void __init disable_smp(void)
726 cpu_possible_map = cpumask_of_cpu(0);
727 cpu_present_map = cpumask_of_cpu(0);
728 smpboot_clear_io_apic_irqs();
729 phys_cpu_present_map = physid_mask_of_physid(0);
730 map_cpu_to_logical_apicid();
731 cpu_set(0, per_cpu(cpu_sibling_map, 0));
732 cpu_set(0, per_cpu(cpu_core_map, 0));
735 static int __init smp_sanity_check(unsigned max_cpus)
738 * If we couldn't find an SMP configuration at boot time,
739 * get out of here now!
741 if (!smp_found_config && !acpi_lapic) {
742 printk(KERN_NOTICE "SMP motherboard not detected.\n");
744 if (APIC_init_uniprocessor())
745 printk(KERN_NOTICE "Local APIC not detected."
746 " Using dummy APIC emulation.\n");
751 * Should not be necessary because the MP table should list the boot
752 * CPU too, but we do it for the sake of robustness anyway.
753 * Makes no sense to do this check in clustered apic mode, so skip it
755 if (!check_phys_apicid_present(boot_cpu_physical_apicid)) {
756 printk("weird, boot CPU (#%d) not listed by the BIOS.\n",
757 boot_cpu_physical_apicid);
758 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
762 * If we couldn't find a local APIC, then get out of here now!
764 if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid]) && !cpu_has_apic) {
765 printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
766 boot_cpu_physical_apicid);
767 printk(KERN_ERR "... forcing use of dummy APIC emulation. (tell your hw vendor)\n");
774 * If SMP should be disabled, then really disable it!
777 smp_found_config = 0;
778 printk(KERN_INFO "SMP mode deactivated, forcing use of dummy APIC emulation.\n");
780 if (nmi_watchdog == NMI_LOCAL_APIC) {
781 printk(KERN_INFO "activating minimal APIC for NMI watchdog use.\n");
784 end_local_APIC_setup();
792 * Cycle through the processors sending APIC IPIs to boot each.
794 static void __init smp_boot_cpus(unsigned int max_cpus)
797 * Setup boot CPU information
799 smp_store_cpu_info(0); /* Final full version of the data */
800 printk(KERN_INFO "CPU%d: ", 0);
801 print_cpu_info(&cpu_data(0));
803 boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
804 boot_cpu_logical_apicid = logical_smp_processor_id();
806 current_thread_info()->cpu = 0;
808 set_cpu_sibling_map(0);
810 if (smp_sanity_check(max_cpus) < 0) {
811 printk(KERN_INFO "SMP disabled\n");
818 end_local_APIC_setup();
819 map_cpu_to_logical_apicid();
822 setup_portio_remap();
824 smpboot_setup_io_apic();
829 /* These are wrappers to interface to the new boot process. Someone
830 who understands all this stuff should rewrite it properly. --RR 15/Jul/02 */
831 void __init native_smp_prepare_cpus(unsigned int max_cpus)
833 nmi_watchdog_default();
834 cpu_callin_map = cpumask_of_cpu(0);
836 smp_boot_cpus(max_cpus);
839 void __init native_smp_prepare_boot_cpu(void)
841 unsigned int cpu = smp_processor_id();
846 cpu_set(cpu, cpu_callout_map);
847 __get_cpu_var(cpu_state) = CPU_ONLINE;
850 int __cpuinit native_cpu_up(unsigned int cpu)
852 int apicid = cpu_present_to_apicid(cpu);
855 WARN_ON(irqs_disabled());
857 Dprintk("++++++++++++++++++++=_---CPU UP %u\n", cpu);
859 if (apicid == BAD_APICID || apicid == boot_cpu_physical_apicid ||
860 !physid_isset(apicid, phys_cpu_present_map)) {
861 printk(KERN_ERR "%s: bad cpu %d\n", __func__, cpu);
865 per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
867 __smp_prepare_cpu(cpu);
869 /* In case one didn't come up */
870 if (!cpu_isset(cpu, cpu_callin_map)) {
871 printk(KERN_DEBUG "skipping cpu%d, didn't come online\n", cpu);
877 * Check TSC synchronization with the AP (keep irqs disabled
880 local_irq_save(flags);
881 check_tsc_sync_source(cpu);
882 local_irq_restore(flags);
884 while (!cpu_isset(cpu, cpu_online_map)) {
886 touch_nmi_watchdog();
892 extern void impress_friends(void);
893 extern void smp_checks(void);
895 void __init native_smp_cpus_done(unsigned int max_cpus)
898 * Cleanup possible dangling ends...
900 smpboot_restore_warm_reset_vector();
902 Dprintk("Boot done.\n");
906 #ifdef CONFIG_X86_IO_APIC
909 check_nmi_watchdog();