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1// SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * x86 SMP booting functions
4 *
5 * (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
6 * (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
7 * Copyright 2001 Andi Kleen, SuSE Labs.
8 *
9 * Much of the core SMP work is based on previous work by Thomas Radke, to
10 * whom a great many thanks are extended.
11 *
12 * Thanks to Intel for making available several different Pentium,
13 * Pentium Pro and Pentium-II/Xeon MP machines.
14 * Original development of Linux SMP code supported by Caldera.
15 *
16 * Fixes
17 * Felix Koop : NR_CPUS used properly
18 * Jose Renau : Handle single CPU case.
19 * Alan Cox : By repeated request 8) - Total BogoMIPS report.
20 * Greg Wright : Fix for kernel stacks panic.
21 * Erich Boleyn : MP v1.4 and additional changes.
22 * Matthias Sattler : Changes for 2.1 kernel map.
23 * Michel Lespinasse : Changes for 2.1 kernel map.
24 * Michael Chastain : Change trampoline.S to gnu as.
25 * Alan Cox : Dumb bug: 'B' step PPro's are fine
26 * Ingo Molnar : Added APIC timers, based on code
27 * from Jose Renau
28 * Ingo Molnar : various cleanups and rewrites
29 * Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug.
30 * Maciej W. Rozycki : Bits for genuine 82489DX APICs
31 * Andi Kleen : Changed for SMP boot into long mode.
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.
35 * Andi Kleen : Converted to new state machine.
36 * Ashok Raj : CPU hotplug support
37 * Glauber Costa : i386 and x86_64 integration
38 */
39
40#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
41
42#include <linux/init.h>
43#include <linux/smp.h>
44#include <linux/export.h>
45#include <linux/sched.h>
46#include <linux/sched/topology.h>
47#include <linux/sched/hotplug.h>
48#include <linux/sched/task_stack.h>
49#include <linux/percpu.h>
50#include <linux/memblock.h>
51#include <linux/err.h>
52#include <linux/nmi.h>
53#include <linux/tboot.h>
54#include <linux/gfp.h>
55#include <linux/cpuidle.h>
56#include <linux/numa.h>
57#include <linux/pgtable.h>
58#include <linux/overflow.h>
59#include <linux/stackprotector.h>
60
61#include <asm/acpi.h>
62#include <asm/cacheinfo.h>
63#include <asm/desc.h>
64#include <asm/nmi.h>
65#include <asm/irq.h>
66#include <asm/realmode.h>
67#include <asm/cpu.h>
68#include <asm/numa.h>
69#include <asm/tlbflush.h>
70#include <asm/mtrr.h>
71#include <asm/mwait.h>
72#include <asm/apic.h>
73#include <asm/io_apic.h>
74#include <asm/fpu/api.h>
75#include <asm/setup.h>
76#include <asm/uv/uv.h>
77#include <linux/mc146818rtc.h>
78#include <asm/i8259.h>
79#include <asm/misc.h>
80#include <asm/qspinlock.h>
81#include <asm/intel-family.h>
82#include <asm/cpu_device_id.h>
83#include <asm/spec-ctrl.h>
84#include <asm/hw_irq.h>
85#include <asm/stackprotector.h>
86#include <asm/sev.h>
87
88/* representing HT siblings of each logical CPU */
89DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map);
90EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
91
92/* representing HT and core siblings of each logical CPU */
93DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_core_map);
94EXPORT_PER_CPU_SYMBOL(cpu_core_map);
95
96/* representing HT, core, and die siblings of each logical CPU */
97DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_die_map);
98EXPORT_PER_CPU_SYMBOL(cpu_die_map);
99
100/* Per CPU bogomips and other parameters */
101DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
102EXPORT_PER_CPU_SYMBOL(cpu_info);
103
104/* Logical package management. We might want to allocate that dynamically */
105unsigned int __max_logical_packages __read_mostly;
106EXPORT_SYMBOL(__max_logical_packages);
107static unsigned int logical_packages __read_mostly;
108static unsigned int logical_die __read_mostly;
109
110/* Maximum number of SMT threads on any online core */
111int __read_mostly __max_smt_threads = 1;
112
113/* Flag to indicate if a complete sched domain rebuild is required */
114bool x86_topology_update;
115
116int arch_update_cpu_topology(void)
117{
118 int retval = x86_topology_update;
119
120 x86_topology_update = false;
121 return retval;
122}
123
124static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
125{
126 unsigned long flags;
127
128 spin_lock_irqsave(&rtc_lock, flags);
129 CMOS_WRITE(0xa, 0xf);
130 spin_unlock_irqrestore(&rtc_lock, flags);
131 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_HIGH)) =
132 start_eip >> 4;
133 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) =
134 start_eip & 0xf;
135}
136
137static inline void smpboot_restore_warm_reset_vector(void)
138{
139 unsigned long flags;
140
141 /*
142 * Paranoid: Set warm reset code and vector here back
143 * to default values.
144 */
145 spin_lock_irqsave(&rtc_lock, flags);
146 CMOS_WRITE(0, 0xf);
147 spin_unlock_irqrestore(&rtc_lock, flags);
148
149 *((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0;
150}
151
152/*
153 * Report back to the Boot Processor during boot time or to the caller processor
154 * during CPU online.
155 */
156static void smp_callin(void)
157{
158 int cpuid;
159
160 /*
161 * If waken up by an INIT in an 82489DX configuration
162 * cpu_callout_mask guarantees we don't get here before
163 * an INIT_deassert IPI reaches our local APIC, so it is
164 * now safe to touch our local APIC.
165 */
166 cpuid = smp_processor_id();
167
168 /*
169 * the boot CPU has finished the init stage and is spinning
170 * on callin_map until we finish. We are free to set up this
171 * CPU, first the APIC. (this is probably redundant on most
172 * boards)
173 */
174 apic_ap_setup();
175
176 /*
177 * Save our processor parameters. Note: this information
178 * is needed for clock calibration.
179 */
180 smp_store_cpu_info(cpuid);
181
182 /*
183 * The topology information must be up to date before
184 * calibrate_delay() and notify_cpu_starting().
185 */
186 set_cpu_sibling_map(raw_smp_processor_id());
187
188 ap_init_aperfmperf();
189
190 /*
191 * Get our bogomips.
192 * Update loops_per_jiffy in cpu_data. Previous call to
193 * smp_store_cpu_info() stored a value that is close but not as
194 * accurate as the value just calculated.
195 */
196 calibrate_delay();
197 cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy;
198 pr_debug("Stack at about %p\n", &cpuid);
199
200 wmb();
201
202 notify_cpu_starting(cpuid);
203
204 /*
205 * Allow the master to continue.
206 */
207 cpumask_set_cpu(cpuid, cpu_callin_mask);
208}
209
210static int cpu0_logical_apicid;
211static int enable_start_cpu0;
212/*
213 * Activate a secondary processor.
214 */
215static void notrace start_secondary(void *unused)
216{
217 /*
218 * Don't put *anything* except direct CPU state initialization
219 * before cpu_init(), SMP booting is too fragile that we want to
220 * limit the things done here to the most necessary things.
221 */
222 cr4_init();
223
224#ifdef CONFIG_X86_32
225 /* switch away from the initial page table */
226 load_cr3(swapper_pg_dir);
227 __flush_tlb_all();
228#endif
229 cpu_init_secondary();
230 rcu_cpu_starting(raw_smp_processor_id());
231 x86_cpuinit.early_percpu_clock_init();
232 smp_callin();
233
234 enable_start_cpu0 = 0;
235
236 /* otherwise gcc will move up smp_processor_id before the cpu_init */
237 barrier();
238 /*
239 * Check TSC synchronization with the boot CPU:
240 */
241 check_tsc_sync_target();
242
243 speculative_store_bypass_ht_init();
244
245 /*
246 * Lock vector_lock, set CPU online and bring the vector
247 * allocator online. Online must be set with vector_lock held
248 * to prevent a concurrent irq setup/teardown from seeing a
249 * half valid vector space.
250 */
251 lock_vector_lock();
252 set_cpu_online(smp_processor_id(), true);
253 lapic_online();
254 unlock_vector_lock();
255 cpu_set_state_online(smp_processor_id());
256 x86_platform.nmi_init();
257
258 /* enable local interrupts */
259 local_irq_enable();
260
261 x86_cpuinit.setup_percpu_clockev();
262
263 wmb();
264 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
265}
266
267/**
268 * topology_is_primary_thread - Check whether CPU is the primary SMT thread
269 * @cpu: CPU to check
270 */
271bool topology_is_primary_thread(unsigned int cpu)
272{
273 return apic_id_is_primary_thread(per_cpu(x86_cpu_to_apicid, cpu));
274}
275
276/**
277 * topology_smt_supported - Check whether SMT is supported by the CPUs
278 */
279bool topology_smt_supported(void)
280{
281 return smp_num_siblings > 1;
282}
283
284/**
285 * topology_phys_to_logical_pkg - Map a physical package id to a logical
286 *
287 * Returns logical package id or -1 if not found
288 */
289int topology_phys_to_logical_pkg(unsigned int phys_pkg)
290{
291 int cpu;
292
293 for_each_possible_cpu(cpu) {
294 struct cpuinfo_x86 *c = &cpu_data(cpu);
295
296 if (c->initialized && c->phys_proc_id == phys_pkg)
297 return c->logical_proc_id;
298 }
299 return -1;
300}
301EXPORT_SYMBOL(topology_phys_to_logical_pkg);
302/**
303 * topology_phys_to_logical_die - Map a physical die id to logical
304 *
305 * Returns logical die id or -1 if not found
306 */
307int topology_phys_to_logical_die(unsigned int die_id, unsigned int cur_cpu)
308{
309 int cpu;
310 int proc_id = cpu_data(cur_cpu).phys_proc_id;
311
312 for_each_possible_cpu(cpu) {
313 struct cpuinfo_x86 *c = &cpu_data(cpu);
314
315 if (c->initialized && c->cpu_die_id == die_id &&
316 c->phys_proc_id == proc_id)
317 return c->logical_die_id;
318 }
319 return -1;
320}
321EXPORT_SYMBOL(topology_phys_to_logical_die);
322
323/**
324 * topology_update_package_map - Update the physical to logical package map
325 * @pkg: The physical package id as retrieved via CPUID
326 * @cpu: The cpu for which this is updated
327 */
328int topology_update_package_map(unsigned int pkg, unsigned int cpu)
329{
330 int new;
331
332 /* Already available somewhere? */
333 new = topology_phys_to_logical_pkg(pkg);
334 if (new >= 0)
335 goto found;
336
337 new = logical_packages++;
338 if (new != pkg) {
339 pr_info("CPU %u Converting physical %u to logical package %u\n",
340 cpu, pkg, new);
341 }
342found:
343 cpu_data(cpu).logical_proc_id = new;
344 return 0;
345}
346/**
347 * topology_update_die_map - Update the physical to logical die map
348 * @die: The die id as retrieved via CPUID
349 * @cpu: The cpu for which this is updated
350 */
351int topology_update_die_map(unsigned int die, unsigned int cpu)
352{
353 int new;
354
355 /* Already available somewhere? */
356 new = topology_phys_to_logical_die(die, cpu);
357 if (new >= 0)
358 goto found;
359
360 new = logical_die++;
361 if (new != die) {
362 pr_info("CPU %u Converting physical %u to logical die %u\n",
363 cpu, die, new);
364 }
365found:
366 cpu_data(cpu).logical_die_id = new;
367 return 0;
368}
369
370void __init smp_store_boot_cpu_info(void)
371{
372 int id = 0; /* CPU 0 */
373 struct cpuinfo_x86 *c = &cpu_data(id);
374
375 *c = boot_cpu_data;
376 c->cpu_index = id;
377 topology_update_package_map(c->phys_proc_id, id);
378 topology_update_die_map(c->cpu_die_id, id);
379 c->initialized = true;
380}
381
382/*
383 * The bootstrap kernel entry code has set these up. Save them for
384 * a given CPU
385 */
386void smp_store_cpu_info(int id)
387{
388 struct cpuinfo_x86 *c = &cpu_data(id);
389
390 /* Copy boot_cpu_data only on the first bringup */
391 if (!c->initialized)
392 *c = boot_cpu_data;
393 c->cpu_index = id;
394 /*
395 * During boot time, CPU0 has this setup already. Save the info when
396 * bringing up AP or offlined CPU0.
397 */
398 identify_secondary_cpu(c);
399 c->initialized = true;
400}
401
402static bool
403topology_same_node(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
404{
405 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
406
407 return (cpu_to_node(cpu1) == cpu_to_node(cpu2));
408}
409
410static bool
411topology_sane(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o, const char *name)
412{
413 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
414
415 return !WARN_ONCE(!topology_same_node(c, o),
416 "sched: CPU #%d's %s-sibling CPU #%d is not on the same node! "
417 "[node: %d != %d]. Ignoring dependency.\n",
418 cpu1, name, cpu2, cpu_to_node(cpu1), cpu_to_node(cpu2));
419}
420
421#define link_mask(mfunc, c1, c2) \
422do { \
423 cpumask_set_cpu((c1), mfunc(c2)); \
424 cpumask_set_cpu((c2), mfunc(c1)); \
425} while (0)
426
427static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
428{
429 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
430 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
431
432 if (c->phys_proc_id == o->phys_proc_id &&
433 c->cpu_die_id == o->cpu_die_id &&
434 per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2)) {
435 if (c->cpu_core_id == o->cpu_core_id)
436 return topology_sane(c, o, "smt");
437
438 if ((c->cu_id != 0xff) &&
439 (o->cu_id != 0xff) &&
440 (c->cu_id == o->cu_id))
441 return topology_sane(c, o, "smt");
442 }
443
444 } else if (c->phys_proc_id == o->phys_proc_id &&
445 c->cpu_die_id == o->cpu_die_id &&
446 c->cpu_core_id == o->cpu_core_id) {
447 return topology_sane(c, o, "smt");
448 }
449
450 return false;
451}
452
453static bool match_die(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
454{
455 if (c->phys_proc_id == o->phys_proc_id &&
456 c->cpu_die_id == o->cpu_die_id)
457 return true;
458 return false;
459}
460
461static bool match_l2c(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
462{
463 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
464
465 /* If the arch didn't set up l2c_id, fall back to SMT */
466 if (per_cpu(cpu_l2c_id, cpu1) == BAD_APICID)
467 return match_smt(c, o);
468
469 /* Do not match if L2 cache id does not match: */
470 if (per_cpu(cpu_l2c_id, cpu1) != per_cpu(cpu_l2c_id, cpu2))
471 return false;
472
473 return topology_sane(c, o, "l2c");
474}
475
476/*
477 * Unlike the other levels, we do not enforce keeping a
478 * multicore group inside a NUMA node. If this happens, we will
479 * discard the MC level of the topology later.
480 */
481static bool match_pkg(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
482{
483 if (c->phys_proc_id == o->phys_proc_id)
484 return true;
485 return false;
486}
487
488/*
489 * Define intel_cod_cpu[] for Intel COD (Cluster-on-Die) CPUs.
490 *
491 * Any Intel CPU that has multiple nodes per package and does not
492 * match intel_cod_cpu[] has the SNC (Sub-NUMA Cluster) topology.
493 *
494 * When in SNC mode, these CPUs enumerate an LLC that is shared
495 * by multiple NUMA nodes. The LLC is shared for off-package data
496 * access but private to the NUMA node (half of the package) for
497 * on-package access. CPUID (the source of the information about
498 * the LLC) can only enumerate the cache as shared or unshared,
499 * but not this particular configuration.
500 */
501
502static const struct x86_cpu_id intel_cod_cpu[] = {
503 X86_MATCH_INTEL_FAM6_MODEL(HASWELL_X, 0), /* COD */
504 X86_MATCH_INTEL_FAM6_MODEL(BROADWELL_X, 0), /* COD */
505 X86_MATCH_INTEL_FAM6_MODEL(ANY, 1), /* SNC */
506 {}
507};
508
509static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
510{
511 const struct x86_cpu_id *id = x86_match_cpu(intel_cod_cpu);
512 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
513 bool intel_snc = id && id->driver_data;
514
515 /* Do not match if we do not have a valid APICID for cpu: */
516 if (per_cpu(cpu_llc_id, cpu1) == BAD_APICID)
517 return false;
518
519 /* Do not match if LLC id does not match: */
520 if (per_cpu(cpu_llc_id, cpu1) != per_cpu(cpu_llc_id, cpu2))
521 return false;
522
523 /*
524 * Allow the SNC topology without warning. Return of false
525 * means 'c' does not share the LLC of 'o'. This will be
526 * reflected to userspace.
527 */
528 if (match_pkg(c, o) && !topology_same_node(c, o) && intel_snc)
529 return false;
530
531 return topology_sane(c, o, "llc");
532}
533
534
535#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_CLUSTER) || defined(CONFIG_SCHED_MC)
536static inline int x86_sched_itmt_flags(void)
537{
538 return sysctl_sched_itmt_enabled ? SD_ASYM_PACKING : 0;
539}
540
541#ifdef CONFIG_SCHED_MC
542static int x86_core_flags(void)
543{
544 return cpu_core_flags() | x86_sched_itmt_flags();
545}
546#endif
547#ifdef CONFIG_SCHED_SMT
548static int x86_smt_flags(void)
549{
550 return cpu_smt_flags() | x86_sched_itmt_flags();
551}
552#endif
553#ifdef CONFIG_SCHED_CLUSTER
554static int x86_cluster_flags(void)
555{
556 return cpu_cluster_flags() | x86_sched_itmt_flags();
557}
558#endif
559#endif
560
561static struct sched_domain_topology_level x86_numa_in_package_topology[] = {
562#ifdef CONFIG_SCHED_SMT
563 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
564#endif
565#ifdef CONFIG_SCHED_CLUSTER
566 { cpu_clustergroup_mask, x86_cluster_flags, SD_INIT_NAME(CLS) },
567#endif
568#ifdef CONFIG_SCHED_MC
569 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
570#endif
571 { NULL, },
572};
573
574static struct sched_domain_topology_level x86_hybrid_topology[] = {
575#ifdef CONFIG_SCHED_SMT
576 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
577#endif
578#ifdef CONFIG_SCHED_MC
579 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
580#endif
581 { cpu_cpu_mask, SD_INIT_NAME(DIE) },
582 { NULL, },
583};
584
585static struct sched_domain_topology_level x86_topology[] = {
586#ifdef CONFIG_SCHED_SMT
587 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
588#endif
589#ifdef CONFIG_SCHED_CLUSTER
590 { cpu_clustergroup_mask, x86_cluster_flags, SD_INIT_NAME(CLS) },
591#endif
592#ifdef CONFIG_SCHED_MC
593 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
594#endif
595 { cpu_cpu_mask, SD_INIT_NAME(DIE) },
596 { NULL, },
597};
598
599/*
600 * Set if a package/die has multiple NUMA nodes inside.
601 * AMD Magny-Cours, Intel Cluster-on-Die, and Intel
602 * Sub-NUMA Clustering have this.
603 */
604static bool x86_has_numa_in_package;
605
606void set_cpu_sibling_map(int cpu)
607{
608 bool has_smt = smp_num_siblings > 1;
609 bool has_mp = has_smt || boot_cpu_data.x86_max_cores > 1;
610 struct cpuinfo_x86 *c = &cpu_data(cpu);
611 struct cpuinfo_x86 *o;
612 int i, threads;
613
614 cpumask_set_cpu(cpu, cpu_sibling_setup_mask);
615
616 if (!has_mp) {
617 cpumask_set_cpu(cpu, topology_sibling_cpumask(cpu));
618 cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu));
619 cpumask_set_cpu(cpu, cpu_l2c_shared_mask(cpu));
620 cpumask_set_cpu(cpu, topology_core_cpumask(cpu));
621 cpumask_set_cpu(cpu, topology_die_cpumask(cpu));
622 c->booted_cores = 1;
623 return;
624 }
625
626 for_each_cpu(i, cpu_sibling_setup_mask) {
627 o = &cpu_data(i);
628
629 if (match_pkg(c, o) && !topology_same_node(c, o))
630 x86_has_numa_in_package = true;
631
632 if ((i == cpu) || (has_smt && match_smt(c, o)))
633 link_mask(topology_sibling_cpumask, cpu, i);
634
635 if ((i == cpu) || (has_mp && match_llc(c, o)))
636 link_mask(cpu_llc_shared_mask, cpu, i);
637
638 if ((i == cpu) || (has_mp && match_l2c(c, o)))
639 link_mask(cpu_l2c_shared_mask, cpu, i);
640
641 if ((i == cpu) || (has_mp && match_die(c, o)))
642 link_mask(topology_die_cpumask, cpu, i);
643 }
644
645 threads = cpumask_weight(topology_sibling_cpumask(cpu));
646 if (threads > __max_smt_threads)
647 __max_smt_threads = threads;
648
649 for_each_cpu(i, topology_sibling_cpumask(cpu))
650 cpu_data(i).smt_active = threads > 1;
651
652 /*
653 * This needs a separate iteration over the cpus because we rely on all
654 * topology_sibling_cpumask links to be set-up.
655 */
656 for_each_cpu(i, cpu_sibling_setup_mask) {
657 o = &cpu_data(i);
658
659 if ((i == cpu) || (has_mp && match_pkg(c, o))) {
660 link_mask(topology_core_cpumask, cpu, i);
661
662 /*
663 * Does this new cpu bringup a new core?
664 */
665 if (threads == 1) {
666 /*
667 * for each core in package, increment
668 * the booted_cores for this new cpu
669 */
670 if (cpumask_first(
671 topology_sibling_cpumask(i)) == i)
672 c->booted_cores++;
673 /*
674 * increment the core count for all
675 * the other cpus in this package
676 */
677 if (i != cpu)
678 cpu_data(i).booted_cores++;
679 } else if (i != cpu && !c->booted_cores)
680 c->booted_cores = cpu_data(i).booted_cores;
681 }
682 }
683}
684
685/* maps the cpu to the sched domain representing multi-core */
686const struct cpumask *cpu_coregroup_mask(int cpu)
687{
688 return cpu_llc_shared_mask(cpu);
689}
690
691const struct cpumask *cpu_clustergroup_mask(int cpu)
692{
693 return cpu_l2c_shared_mask(cpu);
694}
695
696static void impress_friends(void)
697{
698 int cpu;
699 unsigned long bogosum = 0;
700 /*
701 * Allow the user to impress friends.
702 */
703 pr_debug("Before bogomips\n");
704 for_each_possible_cpu(cpu)
705 if (cpumask_test_cpu(cpu, cpu_callout_mask))
706 bogosum += cpu_data(cpu).loops_per_jiffy;
707 pr_info("Total of %d processors activated (%lu.%02lu BogoMIPS)\n",
708 num_online_cpus(),
709 bogosum/(500000/HZ),
710 (bogosum/(5000/HZ))%100);
711
712 pr_debug("Before bogocount - setting activated=1\n");
713}
714
715void __inquire_remote_apic(int apicid)
716{
717 unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
718 const char * const names[] = { "ID", "VERSION", "SPIV" };
719 int timeout;
720 u32 status;
721
722 pr_info("Inquiring remote APIC 0x%x...\n", apicid);
723
724 for (i = 0; i < ARRAY_SIZE(regs); i++) {
725 pr_info("... APIC 0x%x %s: ", apicid, names[i]);
726
727 /*
728 * Wait for idle.
729 */
730 status = safe_apic_wait_icr_idle();
731 if (status)
732 pr_cont("a previous APIC delivery may have failed\n");
733
734 apic_icr_write(APIC_DM_REMRD | regs[i], apicid);
735
736 timeout = 0;
737 do {
738 udelay(100);
739 status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
740 } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
741
742 switch (status) {
743 case APIC_ICR_RR_VALID:
744 status = apic_read(APIC_RRR);
745 pr_cont("%08x\n", status);
746 break;
747 default:
748 pr_cont("failed\n");
749 }
750 }
751}
752
753/*
754 * The Multiprocessor Specification 1.4 (1997) example code suggests
755 * that there should be a 10ms delay between the BSP asserting INIT
756 * and de-asserting INIT, when starting a remote processor.
757 * But that slows boot and resume on modern processors, which include
758 * many cores and don't require that delay.
759 *
760 * Cmdline "init_cpu_udelay=" is available to over-ride this delay.
761 * Modern processor families are quirked to remove the delay entirely.
762 */
763#define UDELAY_10MS_DEFAULT 10000
764
765static unsigned int init_udelay = UINT_MAX;
766
767static int __init cpu_init_udelay(char *str)
768{
769 get_option(&str, &init_udelay);
770
771 return 0;
772}
773early_param("cpu_init_udelay", cpu_init_udelay);
774
775static void __init smp_quirk_init_udelay(void)
776{
777 /* if cmdline changed it from default, leave it alone */
778 if (init_udelay != UINT_MAX)
779 return;
780
781 /* if modern processor, use no delay */
782 if (((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 6)) ||
783 ((boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) && (boot_cpu_data.x86 >= 0x18)) ||
784 ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && (boot_cpu_data.x86 >= 0xF))) {
785 init_udelay = 0;
786 return;
787 }
788 /* else, use legacy delay */
789 init_udelay = UDELAY_10MS_DEFAULT;
790}
791
792/*
793 * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
794 * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
795 * won't ... remember to clear down the APIC, etc later.
796 */
797int
798wakeup_secondary_cpu_via_nmi(int apicid, unsigned long start_eip)
799{
800 u32 dm = apic->dest_mode_logical ? APIC_DEST_LOGICAL : APIC_DEST_PHYSICAL;
801 unsigned long send_status, accept_status = 0;
802 int maxlvt;
803
804 /* Target chip */
805 /* Boot on the stack */
806 /* Kick the second */
807 apic_icr_write(APIC_DM_NMI | dm, apicid);
808
809 pr_debug("Waiting for send to finish...\n");
810 send_status = safe_apic_wait_icr_idle();
811
812 /*
813 * Give the other CPU some time to accept the IPI.
814 */
815 udelay(200);
816 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
817 maxlvt = lapic_get_maxlvt();
818 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
819 apic_write(APIC_ESR, 0);
820 accept_status = (apic_read(APIC_ESR) & 0xEF);
821 }
822 pr_debug("NMI sent\n");
823
824 if (send_status)
825 pr_err("APIC never delivered???\n");
826 if (accept_status)
827 pr_err("APIC delivery error (%lx)\n", accept_status);
828
829 return (send_status | accept_status);
830}
831
832static int
833wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
834{
835 unsigned long send_status = 0, accept_status = 0;
836 int maxlvt, num_starts, j;
837
838 maxlvt = lapic_get_maxlvt();
839
840 /*
841 * Be paranoid about clearing APIC errors.
842 */
843 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
844 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
845 apic_write(APIC_ESR, 0);
846 apic_read(APIC_ESR);
847 }
848
849 pr_debug("Asserting INIT\n");
850
851 /*
852 * Turn INIT on target chip
853 */
854 /*
855 * Send IPI
856 */
857 apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT,
858 phys_apicid);
859
860 pr_debug("Waiting for send to finish...\n");
861 send_status = safe_apic_wait_icr_idle();
862
863 udelay(init_udelay);
864
865 pr_debug("Deasserting INIT\n");
866
867 /* Target chip */
868 /* Send IPI */
869 apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid);
870
871 pr_debug("Waiting for send to finish...\n");
872 send_status = safe_apic_wait_icr_idle();
873
874 mb();
875
876 /*
877 * Should we send STARTUP IPIs ?
878 *
879 * Determine this based on the APIC version.
880 * If we don't have an integrated APIC, don't send the STARTUP IPIs.
881 */
882 if (APIC_INTEGRATED(boot_cpu_apic_version))
883 num_starts = 2;
884 else
885 num_starts = 0;
886
887 /*
888 * Run STARTUP IPI loop.
889 */
890 pr_debug("#startup loops: %d\n", num_starts);
891
892 for (j = 1; j <= num_starts; j++) {
893 pr_debug("Sending STARTUP #%d\n", j);
894 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
895 apic_write(APIC_ESR, 0);
896 apic_read(APIC_ESR);
897 pr_debug("After apic_write\n");
898
899 /*
900 * STARTUP IPI
901 */
902
903 /* Target chip */
904 /* Boot on the stack */
905 /* Kick the second */
906 apic_icr_write(APIC_DM_STARTUP | (start_eip >> 12),
907 phys_apicid);
908
909 /*
910 * Give the other CPU some time to accept the IPI.
911 */
912 if (init_udelay == 0)
913 udelay(10);
914 else
915 udelay(300);
916
917 pr_debug("Startup point 1\n");
918
919 pr_debug("Waiting for send to finish...\n");
920 send_status = safe_apic_wait_icr_idle();
921
922 /*
923 * Give the other CPU some time to accept the IPI.
924 */
925 if (init_udelay == 0)
926 udelay(10);
927 else
928 udelay(200);
929
930 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
931 apic_write(APIC_ESR, 0);
932 accept_status = (apic_read(APIC_ESR) & 0xEF);
933 if (send_status || accept_status)
934 break;
935 }
936 pr_debug("After Startup\n");
937
938 if (send_status)
939 pr_err("APIC never delivered???\n");
940 if (accept_status)
941 pr_err("APIC delivery error (%lx)\n", accept_status);
942
943 return (send_status | accept_status);
944}
945
946/* reduce the number of lines printed when booting a large cpu count system */
947static void announce_cpu(int cpu, int apicid)
948{
949 static int current_node = NUMA_NO_NODE;
950 int node = early_cpu_to_node(cpu);
951 static int width, node_width;
952
953 if (!width)
954 width = num_digits(num_possible_cpus()) + 1; /* + '#' sign */
955
956 if (!node_width)
957 node_width = num_digits(num_possible_nodes()) + 1; /* + '#' */
958
959 if (cpu == 1)
960 printk(KERN_INFO "x86: Booting SMP configuration:\n");
961
962 if (system_state < SYSTEM_RUNNING) {
963 if (node != current_node) {
964 if (current_node > (-1))
965 pr_cont("\n");
966 current_node = node;
967
968 printk(KERN_INFO ".... node %*s#%d, CPUs: ",
969 node_width - num_digits(node), " ", node);
970 }
971
972 /* Add padding for the BSP */
973 if (cpu == 1)
974 pr_cont("%*s", width + 1, " ");
975
976 pr_cont("%*s#%d", width - num_digits(cpu), " ", cpu);
977
978 } else
979 pr_info("Booting Node %d Processor %d APIC 0x%x\n",
980 node, cpu, apicid);
981}
982
983static int wakeup_cpu0_nmi(unsigned int cmd, struct pt_regs *regs)
984{
985 int cpu;
986
987 cpu = smp_processor_id();
988 if (cpu == 0 && !cpu_online(cpu) && enable_start_cpu0)
989 return NMI_HANDLED;
990
991 return NMI_DONE;
992}
993
994/*
995 * Wake up AP by INIT, INIT, STARTUP sequence.
996 *
997 * Instead of waiting for STARTUP after INITs, BSP will execute the BIOS
998 * boot-strap code which is not a desired behavior for waking up BSP. To
999 * void the boot-strap code, wake up CPU0 by NMI instead.
1000 *
1001 * This works to wake up soft offlined CPU0 only. If CPU0 is hard offlined
1002 * (i.e. physically hot removed and then hot added), NMI won't wake it up.
1003 * We'll change this code in the future to wake up hard offlined CPU0 if
1004 * real platform and request are available.
1005 */
1006static int
1007wakeup_cpu_via_init_nmi(int cpu, unsigned long start_ip, int apicid,
1008 int *cpu0_nmi_registered)
1009{
1010 int id;
1011 int boot_error;
1012
1013 preempt_disable();
1014
1015 /*
1016 * Wake up AP by INIT, INIT, STARTUP sequence.
1017 */
1018 if (cpu) {
1019 boot_error = wakeup_secondary_cpu_via_init(apicid, start_ip);
1020 goto out;
1021 }
1022
1023 /*
1024 * Wake up BSP by nmi.
1025 *
1026 * Register a NMI handler to help wake up CPU0.
1027 */
1028 boot_error = register_nmi_handler(NMI_LOCAL,
1029 wakeup_cpu0_nmi, 0, "wake_cpu0");
1030
1031 if (!boot_error) {
1032 enable_start_cpu0 = 1;
1033 *cpu0_nmi_registered = 1;
1034 id = apic->dest_mode_logical ? cpu0_logical_apicid : apicid;
1035 boot_error = wakeup_secondary_cpu_via_nmi(id, start_ip);
1036 }
1037
1038out:
1039 preempt_enable();
1040
1041 return boot_error;
1042}
1043
1044int common_cpu_up(unsigned int cpu, struct task_struct *idle)
1045{
1046 int ret;
1047
1048 /* Just in case we booted with a single CPU. */
1049 alternatives_enable_smp();
1050
1051 per_cpu(pcpu_hot.current_task, cpu) = idle;
1052 cpu_init_stack_canary(cpu, idle);
1053
1054 /* Initialize the interrupt stack(s) */
1055 ret = irq_init_percpu_irqstack(cpu);
1056 if (ret)
1057 return ret;
1058
1059#ifdef CONFIG_X86_32
1060 /* Stack for startup_32 can be just as for start_secondary onwards */
1061 per_cpu(pcpu_hot.top_of_stack, cpu) = task_top_of_stack(idle);
1062#else
1063 initial_gs = per_cpu_offset(cpu);
1064#endif
1065 return 0;
1066}
1067
1068/*
1069 * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
1070 * (ie clustered apic addressing mode), this is a LOGICAL apic ID.
1071 * Returns zero if CPU booted OK, else error code from
1072 * ->wakeup_secondary_cpu.
1073 */
1074static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle,
1075 int *cpu0_nmi_registered)
1076{
1077 /* start_ip had better be page-aligned! */
1078 unsigned long start_ip = real_mode_header->trampoline_start;
1079
1080 unsigned long boot_error = 0;
1081 unsigned long timeout;
1082
1083#ifdef CONFIG_X86_64
1084 /* If 64-bit wakeup method exists, use the 64-bit mode trampoline IP */
1085 if (apic->wakeup_secondary_cpu_64)
1086 start_ip = real_mode_header->trampoline_start64;
1087#endif
1088 idle->thread.sp = (unsigned long)task_pt_regs(idle);
1089 early_gdt_descr.address = (unsigned long)get_cpu_gdt_rw(cpu);
1090 initial_code = (unsigned long)start_secondary;
1091 initial_stack = idle->thread.sp;
1092
1093 /* Enable the espfix hack for this CPU */
1094 init_espfix_ap(cpu);
1095
1096 /* So we see what's up */
1097 announce_cpu(cpu, apicid);
1098
1099 /*
1100 * This grunge runs the startup process for
1101 * the targeted processor.
1102 */
1103
1104 if (x86_platform.legacy.warm_reset) {
1105
1106 pr_debug("Setting warm reset code and vector.\n");
1107
1108 smpboot_setup_warm_reset_vector(start_ip);
1109 /*
1110 * Be paranoid about clearing APIC errors.
1111 */
1112 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
1113 apic_write(APIC_ESR, 0);
1114 apic_read(APIC_ESR);
1115 }
1116 }
1117
1118 /*
1119 * AP might wait on cpu_callout_mask in cpu_init() with
1120 * cpu_initialized_mask set if previous attempt to online
1121 * it timed-out. Clear cpu_initialized_mask so that after
1122 * INIT/SIPI it could start with a clean state.
1123 */
1124 cpumask_clear_cpu(cpu, cpu_initialized_mask);
1125 smp_mb();
1126
1127 /*
1128 * Wake up a CPU in difference cases:
1129 * - Use a method from the APIC driver if one defined, with wakeup
1130 * straight to 64-bit mode preferred over wakeup to RM.
1131 * Otherwise,
1132 * - Use an INIT boot APIC message for APs or NMI for BSP.
1133 */
1134 if (apic->wakeup_secondary_cpu_64)
1135 boot_error = apic->wakeup_secondary_cpu_64(apicid, start_ip);
1136 else if (apic->wakeup_secondary_cpu)
1137 boot_error = apic->wakeup_secondary_cpu(apicid, start_ip);
1138 else
1139 boot_error = wakeup_cpu_via_init_nmi(cpu, start_ip, apicid,
1140 cpu0_nmi_registered);
1141
1142 if (!boot_error) {
1143 /*
1144 * Wait 10s total for first sign of life from AP
1145 */
1146 boot_error = -1;
1147 timeout = jiffies + 10*HZ;
1148 while (time_before(jiffies, timeout)) {
1149 if (cpumask_test_cpu(cpu, cpu_initialized_mask)) {
1150 /*
1151 * Tell AP to proceed with initialization
1152 */
1153 cpumask_set_cpu(cpu, cpu_callout_mask);
1154 boot_error = 0;
1155 break;
1156 }
1157 schedule();
1158 }
1159 }
1160
1161 if (!boot_error) {
1162 /*
1163 * Wait till AP completes initial initialization
1164 */
1165 while (!cpumask_test_cpu(cpu, cpu_callin_mask)) {
1166 /*
1167 * Allow other tasks to run while we wait for the
1168 * AP to come online. This also gives a chance
1169 * for the MTRR work(triggered by the AP coming online)
1170 * to be completed in the stop machine context.
1171 */
1172 schedule();
1173 }
1174 }
1175
1176 if (x86_platform.legacy.warm_reset) {
1177 /*
1178 * Cleanup possible dangling ends...
1179 */
1180 smpboot_restore_warm_reset_vector();
1181 }
1182
1183 return boot_error;
1184}
1185
1186int native_cpu_up(unsigned int cpu, struct task_struct *tidle)
1187{
1188 int apicid = apic->cpu_present_to_apicid(cpu);
1189 int cpu0_nmi_registered = 0;
1190 unsigned long flags;
1191 int err, ret = 0;
1192
1193 lockdep_assert_irqs_enabled();
1194
1195 pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu);
1196
1197 if (apicid == BAD_APICID ||
1198 !physid_isset(apicid, phys_cpu_present_map) ||
1199 !apic->apic_id_valid(apicid)) {
1200 pr_err("%s: bad cpu %d\n", __func__, cpu);
1201 return -EINVAL;
1202 }
1203
1204 /*
1205 * Already booted CPU?
1206 */
1207 if (cpumask_test_cpu(cpu, cpu_callin_mask)) {
1208 pr_debug("do_boot_cpu %d Already started\n", cpu);
1209 return -ENOSYS;
1210 }
1211
1212 /*
1213 * Save current MTRR state in case it was changed since early boot
1214 * (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync:
1215 */
1216 mtrr_save_state();
1217
1218 /* x86 CPUs take themselves offline, so delayed offline is OK. */
1219 err = cpu_check_up_prepare(cpu);
1220 if (err && err != -EBUSY)
1221 return err;
1222
1223 /* the FPU context is blank, nobody can own it */
1224 per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL;
1225
1226 err = common_cpu_up(cpu, tidle);
1227 if (err)
1228 return err;
1229
1230 err = do_boot_cpu(apicid, cpu, tidle, &cpu0_nmi_registered);
1231 if (err) {
1232 pr_err("do_boot_cpu failed(%d) to wakeup CPU#%u\n", err, cpu);
1233 ret = -EIO;
1234 goto unreg_nmi;
1235 }
1236
1237 /*
1238 * Check TSC synchronization with the AP (keep irqs disabled
1239 * while doing so):
1240 */
1241 local_irq_save(flags);
1242 check_tsc_sync_source(cpu);
1243 local_irq_restore(flags);
1244
1245 while (!cpu_online(cpu)) {
1246 cpu_relax();
1247 touch_nmi_watchdog();
1248 }
1249
1250unreg_nmi:
1251 /*
1252 * Clean up the nmi handler. Do this after the callin and callout sync
1253 * to avoid impact of possible long unregister time.
1254 */
1255 if (cpu0_nmi_registered)
1256 unregister_nmi_handler(NMI_LOCAL, "wake_cpu0");
1257
1258 return ret;
1259}
1260
1261/**
1262 * arch_disable_smp_support() - disables SMP support for x86 at runtime
1263 */
1264void arch_disable_smp_support(void)
1265{
1266 disable_ioapic_support();
1267}
1268
1269/*
1270 * Fall back to non SMP mode after errors.
1271 *
1272 * RED-PEN audit/test this more. I bet there is more state messed up here.
1273 */
1274static __init void disable_smp(void)
1275{
1276 pr_info("SMP disabled\n");
1277
1278 disable_ioapic_support();
1279
1280 init_cpu_present(cpumask_of(0));
1281 init_cpu_possible(cpumask_of(0));
1282
1283 if (smp_found_config)
1284 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1285 else
1286 physid_set_mask_of_physid(0, &phys_cpu_present_map);
1287 cpumask_set_cpu(0, topology_sibling_cpumask(0));
1288 cpumask_set_cpu(0, topology_core_cpumask(0));
1289 cpumask_set_cpu(0, topology_die_cpumask(0));
1290}
1291
1292/*
1293 * Various sanity checks.
1294 */
1295static void __init smp_sanity_check(void)
1296{
1297 preempt_disable();
1298
1299#if !defined(CONFIG_X86_BIGSMP) && defined(CONFIG_X86_32)
1300 if (def_to_bigsmp && nr_cpu_ids > 8) {
1301 unsigned int cpu;
1302 unsigned nr;
1303
1304 pr_warn("More than 8 CPUs detected - skipping them\n"
1305 "Use CONFIG_X86_BIGSMP\n");
1306
1307 nr = 0;
1308 for_each_present_cpu(cpu) {
1309 if (nr >= 8)
1310 set_cpu_present(cpu, false);
1311 nr++;
1312 }
1313
1314 nr = 0;
1315 for_each_possible_cpu(cpu) {
1316 if (nr >= 8)
1317 set_cpu_possible(cpu, false);
1318 nr++;
1319 }
1320
1321 set_nr_cpu_ids(8);
1322 }
1323#endif
1324
1325 if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
1326 pr_warn("weird, boot CPU (#%d) not listed by the BIOS\n",
1327 hard_smp_processor_id());
1328
1329 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1330 }
1331
1332 /*
1333 * Should not be necessary because the MP table should list the boot
1334 * CPU too, but we do it for the sake of robustness anyway.
1335 */
1336 if (!apic->check_phys_apicid_present(boot_cpu_physical_apicid)) {
1337 pr_notice("weird, boot CPU (#%d) not listed by the BIOS\n",
1338 boot_cpu_physical_apicid);
1339 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1340 }
1341 preempt_enable();
1342}
1343
1344static void __init smp_cpu_index_default(void)
1345{
1346 int i;
1347 struct cpuinfo_x86 *c;
1348
1349 for_each_possible_cpu(i) {
1350 c = &cpu_data(i);
1351 /* mark all to hotplug */
1352 c->cpu_index = nr_cpu_ids;
1353 }
1354}
1355
1356static void __init smp_get_logical_apicid(void)
1357{
1358 if (x2apic_mode)
1359 cpu0_logical_apicid = apic_read(APIC_LDR);
1360 else
1361 cpu0_logical_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
1362}
1363
1364void __init smp_prepare_cpus_common(void)
1365{
1366 unsigned int i;
1367
1368 smp_cpu_index_default();
1369
1370 /*
1371 * Setup boot CPU information
1372 */
1373 smp_store_boot_cpu_info(); /* Final full version of the data */
1374 cpumask_copy(cpu_callin_mask, cpumask_of(0));
1375 mb();
1376
1377 for_each_possible_cpu(i) {
1378 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
1379 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
1380 zalloc_cpumask_var(&per_cpu(cpu_die_map, i), GFP_KERNEL);
1381 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
1382 zalloc_cpumask_var(&per_cpu(cpu_l2c_shared_map, i), GFP_KERNEL);
1383 }
1384
1385 /*
1386 * Set 'default' x86 topology, this matches default_topology() in that
1387 * it has NUMA nodes as a topology level. See also
1388 * native_smp_cpus_done().
1389 *
1390 * Must be done before set_cpus_sibling_map() is ran.
1391 */
1392 set_sched_topology(x86_topology);
1393
1394 set_cpu_sibling_map(0);
1395}
1396
1397/*
1398 * Prepare for SMP bootup.
1399 * @max_cpus: configured maximum number of CPUs, It is a legacy parameter
1400 * for common interface support.
1401 */
1402void __init native_smp_prepare_cpus(unsigned int max_cpus)
1403{
1404 smp_prepare_cpus_common();
1405
1406 smp_sanity_check();
1407
1408 switch (apic_intr_mode) {
1409 case APIC_PIC:
1410 case APIC_VIRTUAL_WIRE_NO_CONFIG:
1411 disable_smp();
1412 return;
1413 case APIC_SYMMETRIC_IO_NO_ROUTING:
1414 disable_smp();
1415 /* Setup local timer */
1416 x86_init.timers.setup_percpu_clockev();
1417 return;
1418 case APIC_VIRTUAL_WIRE:
1419 case APIC_SYMMETRIC_IO:
1420 break;
1421 }
1422
1423 /* Setup local timer */
1424 x86_init.timers.setup_percpu_clockev();
1425
1426 smp_get_logical_apicid();
1427
1428 pr_info("CPU0: ");
1429 print_cpu_info(&cpu_data(0));
1430
1431 uv_system_init();
1432
1433 smp_quirk_init_udelay();
1434
1435 speculative_store_bypass_ht_init();
1436
1437 snp_set_wakeup_secondary_cpu();
1438}
1439
1440void arch_thaw_secondary_cpus_begin(void)
1441{
1442 set_cache_aps_delayed_init(true);
1443}
1444
1445void arch_thaw_secondary_cpus_end(void)
1446{
1447 cache_aps_init();
1448}
1449
1450/*
1451 * Early setup to make printk work.
1452 */
1453void __init native_smp_prepare_boot_cpu(void)
1454{
1455 int me = smp_processor_id();
1456
1457 /* SMP handles this from setup_per_cpu_areas() */
1458 if (!IS_ENABLED(CONFIG_SMP))
1459 switch_gdt_and_percpu_base(me);
1460
1461 /* already set me in cpu_online_mask in boot_cpu_init() */
1462 cpumask_set_cpu(me, cpu_callout_mask);
1463 cpu_set_state_online(me);
1464 native_pv_lock_init();
1465}
1466
1467void __init calculate_max_logical_packages(void)
1468{
1469 int ncpus;
1470
1471 /*
1472 * Today neither Intel nor AMD support heterogeneous systems so
1473 * extrapolate the boot cpu's data to all packages.
1474 */
1475 ncpus = cpu_data(0).booted_cores * topology_max_smt_threads();
1476 __max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus);
1477 pr_info("Max logical packages: %u\n", __max_logical_packages);
1478}
1479
1480void __init native_smp_cpus_done(unsigned int max_cpus)
1481{
1482 pr_debug("Boot done\n");
1483
1484 calculate_max_logical_packages();
1485
1486 /* XXX for now assume numa-in-package and hybrid don't overlap */
1487 if (x86_has_numa_in_package)
1488 set_sched_topology(x86_numa_in_package_topology);
1489 if (cpu_feature_enabled(X86_FEATURE_HYBRID_CPU))
1490 set_sched_topology(x86_hybrid_topology);
1491
1492 nmi_selftest();
1493 impress_friends();
1494 cache_aps_init();
1495}
1496
1497static int __initdata setup_possible_cpus = -1;
1498static int __init _setup_possible_cpus(char *str)
1499{
1500 get_option(&str, &setup_possible_cpus);
1501 return 0;
1502}
1503early_param("possible_cpus", _setup_possible_cpus);
1504
1505
1506/*
1507 * cpu_possible_mask should be static, it cannot change as cpu's
1508 * are onlined, or offlined. The reason is per-cpu data-structures
1509 * are allocated by some modules at init time, and don't expect to
1510 * do this dynamically on cpu arrival/departure.
1511 * cpu_present_mask on the other hand can change dynamically.
1512 * In case when cpu_hotplug is not compiled, then we resort to current
1513 * behaviour, which is cpu_possible == cpu_present.
1514 * - Ashok Raj
1515 *
1516 * Three ways to find out the number of additional hotplug CPUs:
1517 * - If the BIOS specified disabled CPUs in ACPI/mptables use that.
1518 * - The user can overwrite it with possible_cpus=NUM
1519 * - Otherwise don't reserve additional CPUs.
1520 * We do this because additional CPUs waste a lot of memory.
1521 * -AK
1522 */
1523__init void prefill_possible_map(void)
1524{
1525 int i, possible;
1526
1527 /* No boot processor was found in mptable or ACPI MADT */
1528 if (!num_processors) {
1529 if (boot_cpu_has(X86_FEATURE_APIC)) {
1530 int apicid = boot_cpu_physical_apicid;
1531 int cpu = hard_smp_processor_id();
1532
1533 pr_warn("Boot CPU (id %d) not listed by BIOS\n", cpu);
1534
1535 /* Make sure boot cpu is enumerated */
1536 if (apic->cpu_present_to_apicid(0) == BAD_APICID &&
1537 apic->apic_id_valid(apicid))
1538 generic_processor_info(apicid, boot_cpu_apic_version);
1539 }
1540
1541 if (!num_processors)
1542 num_processors = 1;
1543 }
1544
1545 i = setup_max_cpus ?: 1;
1546 if (setup_possible_cpus == -1) {
1547 possible = num_processors;
1548#ifdef CONFIG_HOTPLUG_CPU
1549 if (setup_max_cpus)
1550 possible += disabled_cpus;
1551#else
1552 if (possible > i)
1553 possible = i;
1554#endif
1555 } else
1556 possible = setup_possible_cpus;
1557
1558 total_cpus = max_t(int, possible, num_processors + disabled_cpus);
1559
1560 /* nr_cpu_ids could be reduced via nr_cpus= */
1561 if (possible > nr_cpu_ids) {
1562 pr_warn("%d Processors exceeds NR_CPUS limit of %u\n",
1563 possible, nr_cpu_ids);
1564 possible = nr_cpu_ids;
1565 }
1566
1567#ifdef CONFIG_HOTPLUG_CPU
1568 if (!setup_max_cpus)
1569#endif
1570 if (possible > i) {
1571 pr_warn("%d Processors exceeds max_cpus limit of %u\n",
1572 possible, setup_max_cpus);
1573 possible = i;
1574 }
1575
1576 set_nr_cpu_ids(possible);
1577
1578 pr_info("Allowing %d CPUs, %d hotplug CPUs\n",
1579 possible, max_t(int, possible - num_processors, 0));
1580
1581 reset_cpu_possible_mask();
1582
1583 for (i = 0; i < possible; i++)
1584 set_cpu_possible(i, true);
1585}
1586
1587#ifdef CONFIG_HOTPLUG_CPU
1588
1589/* Recompute SMT state for all CPUs on offline */
1590static void recompute_smt_state(void)
1591{
1592 int max_threads, cpu;
1593
1594 max_threads = 0;
1595 for_each_online_cpu (cpu) {
1596 int threads = cpumask_weight(topology_sibling_cpumask(cpu));
1597
1598 if (threads > max_threads)
1599 max_threads = threads;
1600 }
1601 __max_smt_threads = max_threads;
1602}
1603
1604static void remove_siblinginfo(int cpu)
1605{
1606 int sibling;
1607 struct cpuinfo_x86 *c = &cpu_data(cpu);
1608
1609 for_each_cpu(sibling, topology_core_cpumask(cpu)) {
1610 cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
1611 /*/
1612 * last thread sibling in this cpu core going down
1613 */
1614 if (cpumask_weight(topology_sibling_cpumask(cpu)) == 1)
1615 cpu_data(sibling).booted_cores--;
1616 }
1617
1618 for_each_cpu(sibling, topology_die_cpumask(cpu))
1619 cpumask_clear_cpu(cpu, topology_die_cpumask(sibling));
1620
1621 for_each_cpu(sibling, topology_sibling_cpumask(cpu)) {
1622 cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
1623 if (cpumask_weight(topology_sibling_cpumask(sibling)) == 1)
1624 cpu_data(sibling).smt_active = false;
1625 }
1626
1627 for_each_cpu(sibling, cpu_llc_shared_mask(cpu))
1628 cpumask_clear_cpu(cpu, cpu_llc_shared_mask(sibling));
1629 for_each_cpu(sibling, cpu_l2c_shared_mask(cpu))
1630 cpumask_clear_cpu(cpu, cpu_l2c_shared_mask(sibling));
1631 cpumask_clear(cpu_llc_shared_mask(cpu));
1632 cpumask_clear(cpu_l2c_shared_mask(cpu));
1633 cpumask_clear(topology_sibling_cpumask(cpu));
1634 cpumask_clear(topology_core_cpumask(cpu));
1635 cpumask_clear(topology_die_cpumask(cpu));
1636 c->cpu_core_id = 0;
1637 c->booted_cores = 0;
1638 cpumask_clear_cpu(cpu, cpu_sibling_setup_mask);
1639 recompute_smt_state();
1640}
1641
1642static void remove_cpu_from_maps(int cpu)
1643{
1644 set_cpu_online(cpu, false);
1645 cpumask_clear_cpu(cpu, cpu_callout_mask);
1646 cpumask_clear_cpu(cpu, cpu_callin_mask);
1647 /* was set by cpu_init() */
1648 cpumask_clear_cpu(cpu, cpu_initialized_mask);
1649 numa_remove_cpu(cpu);
1650}
1651
1652void cpu_disable_common(void)
1653{
1654 int cpu = smp_processor_id();
1655
1656 remove_siblinginfo(cpu);
1657
1658 /* It's now safe to remove this processor from the online map */
1659 lock_vector_lock();
1660 remove_cpu_from_maps(cpu);
1661 unlock_vector_lock();
1662 fixup_irqs();
1663 lapic_offline();
1664}
1665
1666int native_cpu_disable(void)
1667{
1668 int ret;
1669
1670 ret = lapic_can_unplug_cpu();
1671 if (ret)
1672 return ret;
1673
1674 cpu_disable_common();
1675
1676 /*
1677 * Disable the local APIC. Otherwise IPI broadcasts will reach
1678 * it. It still responds normally to INIT, NMI, SMI, and SIPI
1679 * messages.
1680 *
1681 * Disabling the APIC must happen after cpu_disable_common()
1682 * which invokes fixup_irqs().
1683 *
1684 * Disabling the APIC preserves already set bits in IRR, but
1685 * an interrupt arriving after disabling the local APIC does not
1686 * set the corresponding IRR bit.
1687 *
1688 * fixup_irqs() scans IRR for set bits so it can raise a not
1689 * yet handled interrupt on the new destination CPU via an IPI
1690 * but obviously it can't do so for IRR bits which are not set.
1691 * IOW, interrupts arriving after disabling the local APIC will
1692 * be lost.
1693 */
1694 apic_soft_disable();
1695
1696 return 0;
1697}
1698
1699int common_cpu_die(unsigned int cpu)
1700{
1701 int ret = 0;
1702
1703 /* We don't do anything here: idle task is faking death itself. */
1704
1705 /* They ack this in play_dead() by setting CPU_DEAD */
1706 if (cpu_wait_death(cpu, 5)) {
1707 if (system_state == SYSTEM_RUNNING)
1708 pr_info("CPU %u is now offline\n", cpu);
1709 } else {
1710 pr_err("CPU %u didn't die...\n", cpu);
1711 ret = -1;
1712 }
1713
1714 return ret;
1715}
1716
1717void native_cpu_die(unsigned int cpu)
1718{
1719 common_cpu_die(cpu);
1720}
1721
1722void play_dead_common(void)
1723{
1724 idle_task_exit();
1725
1726 /* Ack it */
1727 (void)cpu_report_death();
1728
1729 /*
1730 * With physical CPU hotplug, we should halt the cpu
1731 */
1732 local_irq_disable();
1733}
1734
1735/**
1736 * cond_wakeup_cpu0 - Wake up CPU0 if needed.
1737 *
1738 * If NMI wants to wake up CPU0, start CPU0.
1739 */
1740void cond_wakeup_cpu0(void)
1741{
1742 if (smp_processor_id() == 0 && enable_start_cpu0)
1743 start_cpu0();
1744}
1745EXPORT_SYMBOL_GPL(cond_wakeup_cpu0);
1746
1747/*
1748 * We need to flush the caches before going to sleep, lest we have
1749 * dirty data in our caches when we come back up.
1750 */
1751static inline void mwait_play_dead(void)
1752{
1753 unsigned int eax, ebx, ecx, edx;
1754 unsigned int highest_cstate = 0;
1755 unsigned int highest_subcstate = 0;
1756 void *mwait_ptr;
1757 int i;
1758
1759 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD ||
1760 boot_cpu_data.x86_vendor == X86_VENDOR_HYGON)
1761 return;
1762 if (!this_cpu_has(X86_FEATURE_MWAIT))
1763 return;
1764 if (!this_cpu_has(X86_FEATURE_CLFLUSH))
1765 return;
1766 if (__this_cpu_read(cpu_info.cpuid_level) < CPUID_MWAIT_LEAF)
1767 return;
1768
1769 eax = CPUID_MWAIT_LEAF;
1770 ecx = 0;
1771 native_cpuid(&eax, &ebx, &ecx, &edx);
1772
1773 /*
1774 * eax will be 0 if EDX enumeration is not valid.
1775 * Initialized below to cstate, sub_cstate value when EDX is valid.
1776 */
1777 if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) {
1778 eax = 0;
1779 } else {
1780 edx >>= MWAIT_SUBSTATE_SIZE;
1781 for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {
1782 if (edx & MWAIT_SUBSTATE_MASK) {
1783 highest_cstate = i;
1784 highest_subcstate = edx & MWAIT_SUBSTATE_MASK;
1785 }
1786 }
1787 eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) |
1788 (highest_subcstate - 1);
1789 }
1790
1791 /*
1792 * This should be a memory location in a cache line which is
1793 * unlikely to be touched by other processors. The actual
1794 * content is immaterial as it is not actually modified in any way.
1795 */
1796 mwait_ptr = ¤t_thread_info()->flags;
1797
1798 wbinvd();
1799
1800 while (1) {
1801 /*
1802 * The CLFLUSH is a workaround for erratum AAI65 for
1803 * the Xeon 7400 series. It's not clear it is actually
1804 * needed, but it should be harmless in either case.
1805 * The WBINVD is insufficient due to the spurious-wakeup
1806 * case where we return around the loop.
1807 */
1808 mb();
1809 clflush(mwait_ptr);
1810 mb();
1811 __monitor(mwait_ptr, 0, 0);
1812 mb();
1813 __mwait(eax, 0);
1814
1815 cond_wakeup_cpu0();
1816 }
1817}
1818
1819void hlt_play_dead(void)
1820{
1821 if (__this_cpu_read(cpu_info.x86) >= 4)
1822 wbinvd();
1823
1824 while (1) {
1825 native_halt();
1826
1827 cond_wakeup_cpu0();
1828 }
1829}
1830
1831void native_play_dead(void)
1832{
1833 play_dead_common();
1834 tboot_shutdown(TB_SHUTDOWN_WFS);
1835
1836 mwait_play_dead(); /* Only returns on failure */
1837 if (cpuidle_play_dead())
1838 hlt_play_dead();
1839}
1840
1841#else /* ... !CONFIG_HOTPLUG_CPU */
1842int native_cpu_disable(void)
1843{
1844 return -ENOSYS;
1845}
1846
1847void native_cpu_die(unsigned int cpu)
1848{
1849 /* We said "no" in __cpu_disable */
1850 BUG();
1851}
1852
1853void native_play_dead(void)
1854{
1855 BUG();
1856}
1857
1858#endif
1 /*
2 * x86 SMP booting functions
3 *
4 * (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
5 * (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
6 * Copyright 2001 Andi Kleen, SuSE Labs.
7 *
8 * Much of the core SMP work is based on previous work by Thomas Radke, to
9 * whom a great many thanks are extended.
10 *
11 * Thanks to Intel for making available several different Pentium,
12 * Pentium Pro and Pentium-II/Xeon MP machines.
13 * Original development of Linux SMP code supported by Caldera.
14 *
15 * This code is released under the GNU General Public License version 2 or
16 * later.
17 *
18 * Fixes
19 * Felix Koop : NR_CPUS used properly
20 * Jose Renau : Handle single CPU case.
21 * Alan Cox : By repeated request 8) - Total BogoMIPS report.
22 * Greg Wright : Fix for kernel stacks panic.
23 * Erich Boleyn : MP v1.4 and additional changes.
24 * Matthias Sattler : Changes for 2.1 kernel map.
25 * Michel Lespinasse : Changes for 2.1 kernel map.
26 * Michael Chastain : Change trampoline.S to gnu as.
27 * Alan Cox : Dumb bug: 'B' step PPro's are fine
28 * Ingo Molnar : Added APIC timers, based on code
29 * from Jose Renau
30 * Ingo Molnar : various cleanups and rewrites
31 * Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug.
32 * Maciej W. Rozycki : Bits for genuine 82489DX APICs
33 * Andi Kleen : Changed for SMP boot into long mode.
34 * Martin J. Bligh : Added support for multi-quad systems
35 * Dave Jones : Report invalid combinations of Athlon CPUs.
36 * Rusty Russell : Hacked into shape for new "hotplug" boot process.
37 * Andi Kleen : Converted to new state machine.
38 * Ashok Raj : CPU hotplug support
39 * Glauber Costa : i386 and x86_64 integration
40 */
41
42#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
43
44#include <linux/init.h>
45#include <linux/smp.h>
46#include <linux/export.h>
47#include <linux/sched.h>
48#include <linux/sched/topology.h>
49#include <linux/sched/hotplug.h>
50#include <linux/sched/task_stack.h>
51#include <linux/percpu.h>
52#include <linux/bootmem.h>
53#include <linux/err.h>
54#include <linux/nmi.h>
55#include <linux/tboot.h>
56#include <linux/stackprotector.h>
57#include <linux/gfp.h>
58#include <linux/cpuidle.h>
59
60#include <asm/acpi.h>
61#include <asm/desc.h>
62#include <asm/nmi.h>
63#include <asm/irq.h>
64#include <asm/realmode.h>
65#include <asm/cpu.h>
66#include <asm/numa.h>
67#include <asm/pgtable.h>
68#include <asm/tlbflush.h>
69#include <asm/mtrr.h>
70#include <asm/mwait.h>
71#include <asm/apic.h>
72#include <asm/io_apic.h>
73#include <asm/fpu/internal.h>
74#include <asm/setup.h>
75#include <asm/uv/uv.h>
76#include <linux/mc146818rtc.h>
77#include <asm/i8259.h>
78#include <asm/misc.h>
79#include <asm/qspinlock.h>
80#include <asm/intel-family.h>
81#include <asm/cpu_device_id.h>
82#include <asm/spec-ctrl.h>
83
84/* Number of siblings per CPU package */
85int smp_num_siblings = 1;
86EXPORT_SYMBOL(smp_num_siblings);
87
88/* Last level cache ID of each logical CPU */
89DEFINE_PER_CPU_READ_MOSTLY(u16, cpu_llc_id) = BAD_APICID;
90
91/* representing HT siblings of each logical CPU */
92DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map);
93EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);
94
95/* representing HT and core siblings of each logical CPU */
96DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_core_map);
97EXPORT_PER_CPU_SYMBOL(cpu_core_map);
98
99DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map);
100
101/* Per CPU bogomips and other parameters */
102DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
103EXPORT_PER_CPU_SYMBOL(cpu_info);
104
105/* Logical package management. We might want to allocate that dynamically */
106unsigned int __max_logical_packages __read_mostly;
107EXPORT_SYMBOL(__max_logical_packages);
108static unsigned int logical_packages __read_mostly;
109
110/* Maximum number of SMT threads on any online core */
111int __read_mostly __max_smt_threads = 1;
112
113/* Flag to indicate if a complete sched domain rebuild is required */
114bool x86_topology_update;
115
116int arch_update_cpu_topology(void)
117{
118 int retval = x86_topology_update;
119
120 x86_topology_update = false;
121 return retval;
122}
123
124static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
125{
126 unsigned long flags;
127
128 spin_lock_irqsave(&rtc_lock, flags);
129 CMOS_WRITE(0xa, 0xf);
130 spin_unlock_irqrestore(&rtc_lock, flags);
131 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_HIGH)) =
132 start_eip >> 4;
133 *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) =
134 start_eip & 0xf;
135}
136
137static inline void smpboot_restore_warm_reset_vector(void)
138{
139 unsigned long flags;
140
141 /*
142 * Paranoid: Set warm reset code and vector here back
143 * to default values.
144 */
145 spin_lock_irqsave(&rtc_lock, flags);
146 CMOS_WRITE(0, 0xf);
147 spin_unlock_irqrestore(&rtc_lock, flags);
148
149 *((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0;
150}
151
152/*
153 * Report back to the Boot Processor during boot time or to the caller processor
154 * during CPU online.
155 */
156static void smp_callin(void)
157{
158 int cpuid, phys_id;
159
160 /*
161 * If waken up by an INIT in an 82489DX configuration
162 * cpu_callout_mask guarantees we don't get here before
163 * an INIT_deassert IPI reaches our local APIC, so it is
164 * now safe to touch our local APIC.
165 */
166 cpuid = smp_processor_id();
167
168 /*
169 * (This works even if the APIC is not enabled.)
170 */
171 phys_id = read_apic_id();
172
173 /*
174 * the boot CPU has finished the init stage and is spinning
175 * on callin_map until we finish. We are free to set up this
176 * CPU, first the APIC. (this is probably redundant on most
177 * boards)
178 */
179 apic_ap_setup();
180
181 /*
182 * Save our processor parameters. Note: this information
183 * is needed for clock calibration.
184 */
185 smp_store_cpu_info(cpuid);
186
187 /*
188 * The topology information must be up to date before
189 * calibrate_delay() and notify_cpu_starting().
190 */
191 set_cpu_sibling_map(raw_smp_processor_id());
192
193 /*
194 * Get our bogomips.
195 * Update loops_per_jiffy in cpu_data. Previous call to
196 * smp_store_cpu_info() stored a value that is close but not as
197 * accurate as the value just calculated.
198 */
199 calibrate_delay();
200 cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy;
201 pr_debug("Stack at about %p\n", &cpuid);
202
203 wmb();
204
205 notify_cpu_starting(cpuid);
206
207 /*
208 * Allow the master to continue.
209 */
210 cpumask_set_cpu(cpuid, cpu_callin_mask);
211}
212
213static int cpu0_logical_apicid;
214static int enable_start_cpu0;
215/*
216 * Activate a secondary processor.
217 */
218static void notrace start_secondary(void *unused)
219{
220 /*
221 * Don't put *anything* except direct CPU state initialization
222 * before cpu_init(), SMP booting is too fragile that we want to
223 * limit the things done here to the most necessary things.
224 */
225 if (boot_cpu_has(X86_FEATURE_PCID))
226 __write_cr4(__read_cr4() | X86_CR4_PCIDE);
227
228#ifdef CONFIG_X86_32
229 /* switch away from the initial page table */
230 load_cr3(swapper_pg_dir);
231 __flush_tlb_all();
232#endif
233 load_current_idt();
234 cpu_init();
235 x86_cpuinit.early_percpu_clock_init();
236 preempt_disable();
237 smp_callin();
238
239 enable_start_cpu0 = 0;
240
241 /* otherwise gcc will move up smp_processor_id before the cpu_init */
242 barrier();
243 /*
244 * Check TSC synchronization with the boot CPU:
245 */
246 check_tsc_sync_target();
247
248 speculative_store_bypass_ht_init();
249
250 /*
251 * Lock vector_lock, set CPU online and bring the vector
252 * allocator online. Online must be set with vector_lock held
253 * to prevent a concurrent irq setup/teardown from seeing a
254 * half valid vector space.
255 */
256 lock_vector_lock();
257 set_cpu_online(smp_processor_id(), true);
258 lapic_online();
259 unlock_vector_lock();
260 cpu_set_state_online(smp_processor_id());
261 x86_platform.nmi_init();
262
263 /* enable local interrupts */
264 local_irq_enable();
265
266 /* to prevent fake stack check failure in clock setup */
267 boot_init_stack_canary();
268
269 x86_cpuinit.setup_percpu_clockev();
270
271 wmb();
272 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
273}
274
275/**
276 * topology_phys_to_logical_pkg - Map a physical package id to a logical
277 *
278 * Returns logical package id or -1 if not found
279 */
280int topology_phys_to_logical_pkg(unsigned int phys_pkg)
281{
282 int cpu;
283
284 for_each_possible_cpu(cpu) {
285 struct cpuinfo_x86 *c = &cpu_data(cpu);
286
287 if (c->initialized && c->phys_proc_id == phys_pkg)
288 return c->logical_proc_id;
289 }
290 return -1;
291}
292EXPORT_SYMBOL(topology_phys_to_logical_pkg);
293
294/**
295 * topology_update_package_map - Update the physical to logical package map
296 * @pkg: The physical package id as retrieved via CPUID
297 * @cpu: The cpu for which this is updated
298 */
299int topology_update_package_map(unsigned int pkg, unsigned int cpu)
300{
301 int new;
302
303 /* Already available somewhere? */
304 new = topology_phys_to_logical_pkg(pkg);
305 if (new >= 0)
306 goto found;
307
308 new = logical_packages++;
309 if (new != pkg) {
310 pr_info("CPU %u Converting physical %u to logical package %u\n",
311 cpu, pkg, new);
312 }
313found:
314 cpu_data(cpu).logical_proc_id = new;
315 return 0;
316}
317
318void __init smp_store_boot_cpu_info(void)
319{
320 int id = 0; /* CPU 0 */
321 struct cpuinfo_x86 *c = &cpu_data(id);
322
323 *c = boot_cpu_data;
324 c->cpu_index = id;
325 topology_update_package_map(c->phys_proc_id, id);
326 c->initialized = true;
327}
328
329/*
330 * The bootstrap kernel entry code has set these up. Save them for
331 * a given CPU
332 */
333void smp_store_cpu_info(int id)
334{
335 struct cpuinfo_x86 *c = &cpu_data(id);
336
337 /* Copy boot_cpu_data only on the first bringup */
338 if (!c->initialized)
339 *c = boot_cpu_data;
340 c->cpu_index = id;
341 /*
342 * During boot time, CPU0 has this setup already. Save the info when
343 * bringing up AP or offlined CPU0.
344 */
345 identify_secondary_cpu(c);
346 c->initialized = true;
347}
348
349static bool
350topology_same_node(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
351{
352 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
353
354 return (cpu_to_node(cpu1) == cpu_to_node(cpu2));
355}
356
357static bool
358topology_sane(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o, const char *name)
359{
360 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
361
362 return !WARN_ONCE(!topology_same_node(c, o),
363 "sched: CPU #%d's %s-sibling CPU #%d is not on the same node! "
364 "[node: %d != %d]. Ignoring dependency.\n",
365 cpu1, name, cpu2, cpu_to_node(cpu1), cpu_to_node(cpu2));
366}
367
368#define link_mask(mfunc, c1, c2) \
369do { \
370 cpumask_set_cpu((c1), mfunc(c2)); \
371 cpumask_set_cpu((c2), mfunc(c1)); \
372} while (0)
373
374static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
375{
376 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
377 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
378
379 if (c->phys_proc_id == o->phys_proc_id &&
380 per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2)) {
381 if (c->cpu_core_id == o->cpu_core_id)
382 return topology_sane(c, o, "smt");
383
384 if ((c->cu_id != 0xff) &&
385 (o->cu_id != 0xff) &&
386 (c->cu_id == o->cu_id))
387 return topology_sane(c, o, "smt");
388 }
389
390 } else if (c->phys_proc_id == o->phys_proc_id &&
391 c->cpu_core_id == o->cpu_core_id) {
392 return topology_sane(c, o, "smt");
393 }
394
395 return false;
396}
397
398/*
399 * Define snc_cpu[] for SNC (Sub-NUMA Cluster) CPUs.
400 *
401 * These are Intel CPUs that enumerate an LLC that is shared by
402 * multiple NUMA nodes. The LLC on these systems is shared for
403 * off-package data access but private to the NUMA node (half
404 * of the package) for on-package access.
405 *
406 * CPUID (the source of the information about the LLC) can only
407 * enumerate the cache as being shared *or* unshared, but not
408 * this particular configuration. The CPU in this case enumerates
409 * the cache to be shared across the entire package (spanning both
410 * NUMA nodes).
411 */
412
413static const struct x86_cpu_id snc_cpu[] = {
414 { X86_VENDOR_INTEL, 6, INTEL_FAM6_SKYLAKE_X },
415 {}
416};
417
418static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
419{
420 int cpu1 = c->cpu_index, cpu2 = o->cpu_index;
421
422 /* Do not match if we do not have a valid APICID for cpu: */
423 if (per_cpu(cpu_llc_id, cpu1) == BAD_APICID)
424 return false;
425
426 /* Do not match if LLC id does not match: */
427 if (per_cpu(cpu_llc_id, cpu1) != per_cpu(cpu_llc_id, cpu2))
428 return false;
429
430 /*
431 * Allow the SNC topology without warning. Return of false
432 * means 'c' does not share the LLC of 'o'. This will be
433 * reflected to userspace.
434 */
435 if (!topology_same_node(c, o) && x86_match_cpu(snc_cpu))
436 return false;
437
438 return topology_sane(c, o, "llc");
439}
440
441/*
442 * Unlike the other levels, we do not enforce keeping a
443 * multicore group inside a NUMA node. If this happens, we will
444 * discard the MC level of the topology later.
445 */
446static bool match_die(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o)
447{
448 if (c->phys_proc_id == o->phys_proc_id)
449 return true;
450 return false;
451}
452
453#if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC)
454static inline int x86_sched_itmt_flags(void)
455{
456 return sysctl_sched_itmt_enabled ? SD_ASYM_PACKING : 0;
457}
458
459#ifdef CONFIG_SCHED_MC
460static int x86_core_flags(void)
461{
462 return cpu_core_flags() | x86_sched_itmt_flags();
463}
464#endif
465#ifdef CONFIG_SCHED_SMT
466static int x86_smt_flags(void)
467{
468 return cpu_smt_flags() | x86_sched_itmt_flags();
469}
470#endif
471#endif
472
473static struct sched_domain_topology_level x86_numa_in_package_topology[] = {
474#ifdef CONFIG_SCHED_SMT
475 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
476#endif
477#ifdef CONFIG_SCHED_MC
478 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
479#endif
480 { NULL, },
481};
482
483static struct sched_domain_topology_level x86_topology[] = {
484#ifdef CONFIG_SCHED_SMT
485 { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) },
486#endif
487#ifdef CONFIG_SCHED_MC
488 { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) },
489#endif
490 { cpu_cpu_mask, SD_INIT_NAME(DIE) },
491 { NULL, },
492};
493
494/*
495 * Set if a package/die has multiple NUMA nodes inside.
496 * AMD Magny-Cours, Intel Cluster-on-Die, and Intel
497 * Sub-NUMA Clustering have this.
498 */
499static bool x86_has_numa_in_package;
500
501void set_cpu_sibling_map(int cpu)
502{
503 bool has_smt = smp_num_siblings > 1;
504 bool has_mp = has_smt || boot_cpu_data.x86_max_cores > 1;
505 struct cpuinfo_x86 *c = &cpu_data(cpu);
506 struct cpuinfo_x86 *o;
507 int i, threads;
508
509 cpumask_set_cpu(cpu, cpu_sibling_setup_mask);
510
511 if (!has_mp) {
512 cpumask_set_cpu(cpu, topology_sibling_cpumask(cpu));
513 cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu));
514 cpumask_set_cpu(cpu, topology_core_cpumask(cpu));
515 c->booted_cores = 1;
516 return;
517 }
518
519 for_each_cpu(i, cpu_sibling_setup_mask) {
520 o = &cpu_data(i);
521
522 if ((i == cpu) || (has_smt && match_smt(c, o)))
523 link_mask(topology_sibling_cpumask, cpu, i);
524
525 if ((i == cpu) || (has_mp && match_llc(c, o)))
526 link_mask(cpu_llc_shared_mask, cpu, i);
527
528 }
529
530 /*
531 * This needs a separate iteration over the cpus because we rely on all
532 * topology_sibling_cpumask links to be set-up.
533 */
534 for_each_cpu(i, cpu_sibling_setup_mask) {
535 o = &cpu_data(i);
536
537 if ((i == cpu) || (has_mp && match_die(c, o))) {
538 link_mask(topology_core_cpumask, cpu, i);
539
540 /*
541 * Does this new cpu bringup a new core?
542 */
543 if (cpumask_weight(
544 topology_sibling_cpumask(cpu)) == 1) {
545 /*
546 * for each core in package, increment
547 * the booted_cores for this new cpu
548 */
549 if (cpumask_first(
550 topology_sibling_cpumask(i)) == i)
551 c->booted_cores++;
552 /*
553 * increment the core count for all
554 * the other cpus in this package
555 */
556 if (i != cpu)
557 cpu_data(i).booted_cores++;
558 } else if (i != cpu && !c->booted_cores)
559 c->booted_cores = cpu_data(i).booted_cores;
560 }
561 if (match_die(c, o) && !topology_same_node(c, o))
562 x86_has_numa_in_package = true;
563 }
564
565 threads = cpumask_weight(topology_sibling_cpumask(cpu));
566 if (threads > __max_smt_threads)
567 __max_smt_threads = threads;
568}
569
570/* maps the cpu to the sched domain representing multi-core */
571const struct cpumask *cpu_coregroup_mask(int cpu)
572{
573 return cpu_llc_shared_mask(cpu);
574}
575
576static void impress_friends(void)
577{
578 int cpu;
579 unsigned long bogosum = 0;
580 /*
581 * Allow the user to impress friends.
582 */
583 pr_debug("Before bogomips\n");
584 for_each_possible_cpu(cpu)
585 if (cpumask_test_cpu(cpu, cpu_callout_mask))
586 bogosum += cpu_data(cpu).loops_per_jiffy;
587 pr_info("Total of %d processors activated (%lu.%02lu BogoMIPS)\n",
588 num_online_cpus(),
589 bogosum/(500000/HZ),
590 (bogosum/(5000/HZ))%100);
591
592 pr_debug("Before bogocount - setting activated=1\n");
593}
594
595void __inquire_remote_apic(int apicid)
596{
597 unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 };
598 const char * const names[] = { "ID", "VERSION", "SPIV" };
599 int timeout;
600 u32 status;
601
602 pr_info("Inquiring remote APIC 0x%x...\n", apicid);
603
604 for (i = 0; i < ARRAY_SIZE(regs); i++) {
605 pr_info("... APIC 0x%x %s: ", apicid, names[i]);
606
607 /*
608 * Wait for idle.
609 */
610 status = safe_apic_wait_icr_idle();
611 if (status)
612 pr_cont("a previous APIC delivery may have failed\n");
613
614 apic_icr_write(APIC_DM_REMRD | regs[i], apicid);
615
616 timeout = 0;
617 do {
618 udelay(100);
619 status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK;
620 } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000);
621
622 switch (status) {
623 case APIC_ICR_RR_VALID:
624 status = apic_read(APIC_RRR);
625 pr_cont("%08x\n", status);
626 break;
627 default:
628 pr_cont("failed\n");
629 }
630 }
631}
632
633/*
634 * The Multiprocessor Specification 1.4 (1997) example code suggests
635 * that there should be a 10ms delay between the BSP asserting INIT
636 * and de-asserting INIT, when starting a remote processor.
637 * But that slows boot and resume on modern processors, which include
638 * many cores and don't require that delay.
639 *
640 * Cmdline "init_cpu_udelay=" is available to over-ride this delay.
641 * Modern processor families are quirked to remove the delay entirely.
642 */
643#define UDELAY_10MS_DEFAULT 10000
644
645static unsigned int init_udelay = UINT_MAX;
646
647static int __init cpu_init_udelay(char *str)
648{
649 get_option(&str, &init_udelay);
650
651 return 0;
652}
653early_param("cpu_init_udelay", cpu_init_udelay);
654
655static void __init smp_quirk_init_udelay(void)
656{
657 /* if cmdline changed it from default, leave it alone */
658 if (init_udelay != UINT_MAX)
659 return;
660
661 /* if modern processor, use no delay */
662 if (((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 6)) ||
663 ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && (boot_cpu_data.x86 >= 0xF))) {
664 init_udelay = 0;
665 return;
666 }
667 /* else, use legacy delay */
668 init_udelay = UDELAY_10MS_DEFAULT;
669}
670
671/*
672 * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal
673 * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this
674 * won't ... remember to clear down the APIC, etc later.
675 */
676int
677wakeup_secondary_cpu_via_nmi(int apicid, unsigned long start_eip)
678{
679 unsigned long send_status, accept_status = 0;
680 int maxlvt;
681
682 /* Target chip */
683 /* Boot on the stack */
684 /* Kick the second */
685 apic_icr_write(APIC_DM_NMI | apic->dest_logical, apicid);
686
687 pr_debug("Waiting for send to finish...\n");
688 send_status = safe_apic_wait_icr_idle();
689
690 /*
691 * Give the other CPU some time to accept the IPI.
692 */
693 udelay(200);
694 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
695 maxlvt = lapic_get_maxlvt();
696 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
697 apic_write(APIC_ESR, 0);
698 accept_status = (apic_read(APIC_ESR) & 0xEF);
699 }
700 pr_debug("NMI sent\n");
701
702 if (send_status)
703 pr_err("APIC never delivered???\n");
704 if (accept_status)
705 pr_err("APIC delivery error (%lx)\n", accept_status);
706
707 return (send_status | accept_status);
708}
709
710static int
711wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
712{
713 unsigned long send_status = 0, accept_status = 0;
714 int maxlvt, num_starts, j;
715
716 maxlvt = lapic_get_maxlvt();
717
718 /*
719 * Be paranoid about clearing APIC errors.
720 */
721 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
722 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
723 apic_write(APIC_ESR, 0);
724 apic_read(APIC_ESR);
725 }
726
727 pr_debug("Asserting INIT\n");
728
729 /*
730 * Turn INIT on target chip
731 */
732 /*
733 * Send IPI
734 */
735 apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT,
736 phys_apicid);
737
738 pr_debug("Waiting for send to finish...\n");
739 send_status = safe_apic_wait_icr_idle();
740
741 udelay(init_udelay);
742
743 pr_debug("Deasserting INIT\n");
744
745 /* Target chip */
746 /* Send IPI */
747 apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid);
748
749 pr_debug("Waiting for send to finish...\n");
750 send_status = safe_apic_wait_icr_idle();
751
752 mb();
753
754 /*
755 * Should we send STARTUP IPIs ?
756 *
757 * Determine this based on the APIC version.
758 * If we don't have an integrated APIC, don't send the STARTUP IPIs.
759 */
760 if (APIC_INTEGRATED(boot_cpu_apic_version))
761 num_starts = 2;
762 else
763 num_starts = 0;
764
765 /*
766 * Run STARTUP IPI loop.
767 */
768 pr_debug("#startup loops: %d\n", num_starts);
769
770 for (j = 1; j <= num_starts; j++) {
771 pr_debug("Sending STARTUP #%d\n", j);
772 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
773 apic_write(APIC_ESR, 0);
774 apic_read(APIC_ESR);
775 pr_debug("After apic_write\n");
776
777 /*
778 * STARTUP IPI
779 */
780
781 /* Target chip */
782 /* Boot on the stack */
783 /* Kick the second */
784 apic_icr_write(APIC_DM_STARTUP | (start_eip >> 12),
785 phys_apicid);
786
787 /*
788 * Give the other CPU some time to accept the IPI.
789 */
790 if (init_udelay == 0)
791 udelay(10);
792 else
793 udelay(300);
794
795 pr_debug("Startup point 1\n");
796
797 pr_debug("Waiting for send to finish...\n");
798 send_status = safe_apic_wait_icr_idle();
799
800 /*
801 * Give the other CPU some time to accept the IPI.
802 */
803 if (init_udelay == 0)
804 udelay(10);
805 else
806 udelay(200);
807
808 if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
809 apic_write(APIC_ESR, 0);
810 accept_status = (apic_read(APIC_ESR) & 0xEF);
811 if (send_status || accept_status)
812 break;
813 }
814 pr_debug("After Startup\n");
815
816 if (send_status)
817 pr_err("APIC never delivered???\n");
818 if (accept_status)
819 pr_err("APIC delivery error (%lx)\n", accept_status);
820
821 return (send_status | accept_status);
822}
823
824/* reduce the number of lines printed when booting a large cpu count system */
825static void announce_cpu(int cpu, int apicid)
826{
827 static int current_node = -1;
828 int node = early_cpu_to_node(cpu);
829 static int width, node_width;
830
831 if (!width)
832 width = num_digits(num_possible_cpus()) + 1; /* + '#' sign */
833
834 if (!node_width)
835 node_width = num_digits(num_possible_nodes()) + 1; /* + '#' */
836
837 if (cpu == 1)
838 printk(KERN_INFO "x86: Booting SMP configuration:\n");
839
840 if (system_state < SYSTEM_RUNNING) {
841 if (node != current_node) {
842 if (current_node > (-1))
843 pr_cont("\n");
844 current_node = node;
845
846 printk(KERN_INFO ".... node %*s#%d, CPUs: ",
847 node_width - num_digits(node), " ", node);
848 }
849
850 /* Add padding for the BSP */
851 if (cpu == 1)
852 pr_cont("%*s", width + 1, " ");
853
854 pr_cont("%*s#%d", width - num_digits(cpu), " ", cpu);
855
856 } else
857 pr_info("Booting Node %d Processor %d APIC 0x%x\n",
858 node, cpu, apicid);
859}
860
861static int wakeup_cpu0_nmi(unsigned int cmd, struct pt_regs *regs)
862{
863 int cpu;
864
865 cpu = smp_processor_id();
866 if (cpu == 0 && !cpu_online(cpu) && enable_start_cpu0)
867 return NMI_HANDLED;
868
869 return NMI_DONE;
870}
871
872/*
873 * Wake up AP by INIT, INIT, STARTUP sequence.
874 *
875 * Instead of waiting for STARTUP after INITs, BSP will execute the BIOS
876 * boot-strap code which is not a desired behavior for waking up BSP. To
877 * void the boot-strap code, wake up CPU0 by NMI instead.
878 *
879 * This works to wake up soft offlined CPU0 only. If CPU0 is hard offlined
880 * (i.e. physically hot removed and then hot added), NMI won't wake it up.
881 * We'll change this code in the future to wake up hard offlined CPU0 if
882 * real platform and request are available.
883 */
884static int
885wakeup_cpu_via_init_nmi(int cpu, unsigned long start_ip, int apicid,
886 int *cpu0_nmi_registered)
887{
888 int id;
889 int boot_error;
890
891 preempt_disable();
892
893 /*
894 * Wake up AP by INIT, INIT, STARTUP sequence.
895 */
896 if (cpu) {
897 boot_error = wakeup_secondary_cpu_via_init(apicid, start_ip);
898 goto out;
899 }
900
901 /*
902 * Wake up BSP by nmi.
903 *
904 * Register a NMI handler to help wake up CPU0.
905 */
906 boot_error = register_nmi_handler(NMI_LOCAL,
907 wakeup_cpu0_nmi, 0, "wake_cpu0");
908
909 if (!boot_error) {
910 enable_start_cpu0 = 1;
911 *cpu0_nmi_registered = 1;
912 if (apic->dest_logical == APIC_DEST_LOGICAL)
913 id = cpu0_logical_apicid;
914 else
915 id = apicid;
916 boot_error = wakeup_secondary_cpu_via_nmi(id, start_ip);
917 }
918
919out:
920 preempt_enable();
921
922 return boot_error;
923}
924
925void common_cpu_up(unsigned int cpu, struct task_struct *idle)
926{
927 /* Just in case we booted with a single CPU. */
928 alternatives_enable_smp();
929
930 per_cpu(current_task, cpu) = idle;
931
932#ifdef CONFIG_X86_32
933 /* Stack for startup_32 can be just as for start_secondary onwards */
934 irq_ctx_init(cpu);
935 per_cpu(cpu_current_top_of_stack, cpu) = task_top_of_stack(idle);
936#else
937 initial_gs = per_cpu_offset(cpu);
938#endif
939}
940
941/*
942 * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad
943 * (ie clustered apic addressing mode), this is a LOGICAL apic ID.
944 * Returns zero if CPU booted OK, else error code from
945 * ->wakeup_secondary_cpu.
946 */
947static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle,
948 int *cpu0_nmi_registered)
949{
950 volatile u32 *trampoline_status =
951 (volatile u32 *) __va(real_mode_header->trampoline_status);
952 /* start_ip had better be page-aligned! */
953 unsigned long start_ip = real_mode_header->trampoline_start;
954
955 unsigned long boot_error = 0;
956 unsigned long timeout;
957
958 idle->thread.sp = (unsigned long)task_pt_regs(idle);
959 early_gdt_descr.address = (unsigned long)get_cpu_gdt_rw(cpu);
960 initial_code = (unsigned long)start_secondary;
961 initial_stack = idle->thread.sp;
962
963 /* Enable the espfix hack for this CPU */
964 init_espfix_ap(cpu);
965
966 /* So we see what's up */
967 announce_cpu(cpu, apicid);
968
969 /*
970 * This grunge runs the startup process for
971 * the targeted processor.
972 */
973
974 if (x86_platform.legacy.warm_reset) {
975
976 pr_debug("Setting warm reset code and vector.\n");
977
978 smpboot_setup_warm_reset_vector(start_ip);
979 /*
980 * Be paranoid about clearing APIC errors.
981 */
982 if (APIC_INTEGRATED(boot_cpu_apic_version)) {
983 apic_write(APIC_ESR, 0);
984 apic_read(APIC_ESR);
985 }
986 }
987
988 /*
989 * AP might wait on cpu_callout_mask in cpu_init() with
990 * cpu_initialized_mask set if previous attempt to online
991 * it timed-out. Clear cpu_initialized_mask so that after
992 * INIT/SIPI it could start with a clean state.
993 */
994 cpumask_clear_cpu(cpu, cpu_initialized_mask);
995 smp_mb();
996
997 /*
998 * Wake up a CPU in difference cases:
999 * - Use the method in the APIC driver if it's defined
1000 * Otherwise,
1001 * - Use an INIT boot APIC message for APs or NMI for BSP.
1002 */
1003 if (apic->wakeup_secondary_cpu)
1004 boot_error = apic->wakeup_secondary_cpu(apicid, start_ip);
1005 else
1006 boot_error = wakeup_cpu_via_init_nmi(cpu, start_ip, apicid,
1007 cpu0_nmi_registered);
1008
1009 if (!boot_error) {
1010 /*
1011 * Wait 10s total for first sign of life from AP
1012 */
1013 boot_error = -1;
1014 timeout = jiffies + 10*HZ;
1015 while (time_before(jiffies, timeout)) {
1016 if (cpumask_test_cpu(cpu, cpu_initialized_mask)) {
1017 /*
1018 * Tell AP to proceed with initialization
1019 */
1020 cpumask_set_cpu(cpu, cpu_callout_mask);
1021 boot_error = 0;
1022 break;
1023 }
1024 schedule();
1025 }
1026 }
1027
1028 if (!boot_error) {
1029 /*
1030 * Wait till AP completes initial initialization
1031 */
1032 while (!cpumask_test_cpu(cpu, cpu_callin_mask)) {
1033 /*
1034 * Allow other tasks to run while we wait for the
1035 * AP to come online. This also gives a chance
1036 * for the MTRR work(triggered by the AP coming online)
1037 * to be completed in the stop machine context.
1038 */
1039 schedule();
1040 }
1041 }
1042
1043 /* mark "stuck" area as not stuck */
1044 *trampoline_status = 0;
1045
1046 if (x86_platform.legacy.warm_reset) {
1047 /*
1048 * Cleanup possible dangling ends...
1049 */
1050 smpboot_restore_warm_reset_vector();
1051 }
1052
1053 return boot_error;
1054}
1055
1056int native_cpu_up(unsigned int cpu, struct task_struct *tidle)
1057{
1058 int apicid = apic->cpu_present_to_apicid(cpu);
1059 int cpu0_nmi_registered = 0;
1060 unsigned long flags;
1061 int err, ret = 0;
1062
1063 lockdep_assert_irqs_enabled();
1064
1065 pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu);
1066
1067 if (apicid == BAD_APICID ||
1068 !physid_isset(apicid, phys_cpu_present_map) ||
1069 !apic->apic_id_valid(apicid)) {
1070 pr_err("%s: bad cpu %d\n", __func__, cpu);
1071 return -EINVAL;
1072 }
1073
1074 /*
1075 * Already booted CPU?
1076 */
1077 if (cpumask_test_cpu(cpu, cpu_callin_mask)) {
1078 pr_debug("do_boot_cpu %d Already started\n", cpu);
1079 return -ENOSYS;
1080 }
1081
1082 /*
1083 * Save current MTRR state in case it was changed since early boot
1084 * (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync:
1085 */
1086 mtrr_save_state();
1087
1088 /* x86 CPUs take themselves offline, so delayed offline is OK. */
1089 err = cpu_check_up_prepare(cpu);
1090 if (err && err != -EBUSY)
1091 return err;
1092
1093 /* the FPU context is blank, nobody can own it */
1094 per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL;
1095
1096 common_cpu_up(cpu, tidle);
1097
1098 err = do_boot_cpu(apicid, cpu, tidle, &cpu0_nmi_registered);
1099 if (err) {
1100 pr_err("do_boot_cpu failed(%d) to wakeup CPU#%u\n", err, cpu);
1101 ret = -EIO;
1102 goto unreg_nmi;
1103 }
1104
1105 /*
1106 * Check TSC synchronization with the AP (keep irqs disabled
1107 * while doing so):
1108 */
1109 local_irq_save(flags);
1110 check_tsc_sync_source(cpu);
1111 local_irq_restore(flags);
1112
1113 while (!cpu_online(cpu)) {
1114 cpu_relax();
1115 touch_nmi_watchdog();
1116 }
1117
1118unreg_nmi:
1119 /*
1120 * Clean up the nmi handler. Do this after the callin and callout sync
1121 * to avoid impact of possible long unregister time.
1122 */
1123 if (cpu0_nmi_registered)
1124 unregister_nmi_handler(NMI_LOCAL, "wake_cpu0");
1125
1126 return ret;
1127}
1128
1129/**
1130 * arch_disable_smp_support() - disables SMP support for x86 at runtime
1131 */
1132void arch_disable_smp_support(void)
1133{
1134 disable_ioapic_support();
1135}
1136
1137/*
1138 * Fall back to non SMP mode after errors.
1139 *
1140 * RED-PEN audit/test this more. I bet there is more state messed up here.
1141 */
1142static __init void disable_smp(void)
1143{
1144 pr_info("SMP disabled\n");
1145
1146 disable_ioapic_support();
1147
1148 init_cpu_present(cpumask_of(0));
1149 init_cpu_possible(cpumask_of(0));
1150
1151 if (smp_found_config)
1152 physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map);
1153 else
1154 physid_set_mask_of_physid(0, &phys_cpu_present_map);
1155 cpumask_set_cpu(0, topology_sibling_cpumask(0));
1156 cpumask_set_cpu(0, topology_core_cpumask(0));
1157}
1158
1159/*
1160 * Various sanity checks.
1161 */
1162static void __init smp_sanity_check(void)
1163{
1164 preempt_disable();
1165
1166#if !defined(CONFIG_X86_BIGSMP) && defined(CONFIG_X86_32)
1167 if (def_to_bigsmp && nr_cpu_ids > 8) {
1168 unsigned int cpu;
1169 unsigned nr;
1170
1171 pr_warn("More than 8 CPUs detected - skipping them\n"
1172 "Use CONFIG_X86_BIGSMP\n");
1173
1174 nr = 0;
1175 for_each_present_cpu(cpu) {
1176 if (nr >= 8)
1177 set_cpu_present(cpu, false);
1178 nr++;
1179 }
1180
1181 nr = 0;
1182 for_each_possible_cpu(cpu) {
1183 if (nr >= 8)
1184 set_cpu_possible(cpu, false);
1185 nr++;
1186 }
1187
1188 nr_cpu_ids = 8;
1189 }
1190#endif
1191
1192 if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) {
1193 pr_warn("weird, boot CPU (#%d) not listed by the BIOS\n",
1194 hard_smp_processor_id());
1195
1196 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1197 }
1198
1199 /*
1200 * Should not be necessary because the MP table should list the boot
1201 * CPU too, but we do it for the sake of robustness anyway.
1202 */
1203 if (!apic->check_phys_apicid_present(boot_cpu_physical_apicid)) {
1204 pr_notice("weird, boot CPU (#%d) not listed by the BIOS\n",
1205 boot_cpu_physical_apicid);
1206 physid_set(hard_smp_processor_id(), phys_cpu_present_map);
1207 }
1208 preempt_enable();
1209}
1210
1211static void __init smp_cpu_index_default(void)
1212{
1213 int i;
1214 struct cpuinfo_x86 *c;
1215
1216 for_each_possible_cpu(i) {
1217 c = &cpu_data(i);
1218 /* mark all to hotplug */
1219 c->cpu_index = nr_cpu_ids;
1220 }
1221}
1222
1223static void __init smp_get_logical_apicid(void)
1224{
1225 if (x2apic_mode)
1226 cpu0_logical_apicid = apic_read(APIC_LDR);
1227 else
1228 cpu0_logical_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR));
1229}
1230
1231/*
1232 * Prepare for SMP bootup.
1233 * @max_cpus: configured maximum number of CPUs, It is a legacy parameter
1234 * for common interface support.
1235 */
1236void __init native_smp_prepare_cpus(unsigned int max_cpus)
1237{
1238 unsigned int i;
1239
1240 smp_cpu_index_default();
1241
1242 /*
1243 * Setup boot CPU information
1244 */
1245 smp_store_boot_cpu_info(); /* Final full version of the data */
1246 cpumask_copy(cpu_callin_mask, cpumask_of(0));
1247 mb();
1248
1249 for_each_possible_cpu(i) {
1250 zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL);
1251 zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL);
1252 zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL);
1253 }
1254
1255 /*
1256 * Set 'default' x86 topology, this matches default_topology() in that
1257 * it has NUMA nodes as a topology level. See also
1258 * native_smp_cpus_done().
1259 *
1260 * Must be done before set_cpus_sibling_map() is ran.
1261 */
1262 set_sched_topology(x86_topology);
1263
1264 set_cpu_sibling_map(0);
1265
1266 smp_sanity_check();
1267
1268 switch (apic_intr_mode) {
1269 case APIC_PIC:
1270 case APIC_VIRTUAL_WIRE_NO_CONFIG:
1271 disable_smp();
1272 return;
1273 case APIC_SYMMETRIC_IO_NO_ROUTING:
1274 disable_smp();
1275 /* Setup local timer */
1276 x86_init.timers.setup_percpu_clockev();
1277 return;
1278 case APIC_VIRTUAL_WIRE:
1279 case APIC_SYMMETRIC_IO:
1280 break;
1281 }
1282
1283 /* Setup local timer */
1284 x86_init.timers.setup_percpu_clockev();
1285
1286 smp_get_logical_apicid();
1287
1288 pr_info("CPU0: ");
1289 print_cpu_info(&cpu_data(0));
1290
1291 native_pv_lock_init();
1292
1293 uv_system_init();
1294
1295 set_mtrr_aps_delayed_init();
1296
1297 smp_quirk_init_udelay();
1298
1299 speculative_store_bypass_ht_init();
1300}
1301
1302void arch_enable_nonboot_cpus_begin(void)
1303{
1304 set_mtrr_aps_delayed_init();
1305}
1306
1307void arch_enable_nonboot_cpus_end(void)
1308{
1309 mtrr_aps_init();
1310}
1311
1312/*
1313 * Early setup to make printk work.
1314 */
1315void __init native_smp_prepare_boot_cpu(void)
1316{
1317 int me = smp_processor_id();
1318 switch_to_new_gdt(me);
1319 /* already set me in cpu_online_mask in boot_cpu_init() */
1320 cpumask_set_cpu(me, cpu_callout_mask);
1321 cpu_set_state_online(me);
1322}
1323
1324void __init calculate_max_logical_packages(void)
1325{
1326 int ncpus;
1327
1328 /*
1329 * Today neither Intel nor AMD support heterogenous systems so
1330 * extrapolate the boot cpu's data to all packages.
1331 */
1332 ncpus = cpu_data(0).booted_cores * topology_max_smt_threads();
1333 __max_logical_packages = DIV_ROUND_UP(nr_cpu_ids, ncpus);
1334 pr_info("Max logical packages: %u\n", __max_logical_packages);
1335}
1336
1337void __init native_smp_cpus_done(unsigned int max_cpus)
1338{
1339 pr_debug("Boot done\n");
1340
1341 calculate_max_logical_packages();
1342
1343 if (x86_has_numa_in_package)
1344 set_sched_topology(x86_numa_in_package_topology);
1345
1346 nmi_selftest();
1347 impress_friends();
1348 mtrr_aps_init();
1349}
1350
1351static int __initdata setup_possible_cpus = -1;
1352static int __init _setup_possible_cpus(char *str)
1353{
1354 get_option(&str, &setup_possible_cpus);
1355 return 0;
1356}
1357early_param("possible_cpus", _setup_possible_cpus);
1358
1359
1360/*
1361 * cpu_possible_mask should be static, it cannot change as cpu's
1362 * are onlined, or offlined. The reason is per-cpu data-structures
1363 * are allocated by some modules at init time, and dont expect to
1364 * do this dynamically on cpu arrival/departure.
1365 * cpu_present_mask on the other hand can change dynamically.
1366 * In case when cpu_hotplug is not compiled, then we resort to current
1367 * behaviour, which is cpu_possible == cpu_present.
1368 * - Ashok Raj
1369 *
1370 * Three ways to find out the number of additional hotplug CPUs:
1371 * - If the BIOS specified disabled CPUs in ACPI/mptables use that.
1372 * - The user can overwrite it with possible_cpus=NUM
1373 * - Otherwise don't reserve additional CPUs.
1374 * We do this because additional CPUs waste a lot of memory.
1375 * -AK
1376 */
1377__init void prefill_possible_map(void)
1378{
1379 int i, possible;
1380
1381 /* No boot processor was found in mptable or ACPI MADT */
1382 if (!num_processors) {
1383 if (boot_cpu_has(X86_FEATURE_APIC)) {
1384 int apicid = boot_cpu_physical_apicid;
1385 int cpu = hard_smp_processor_id();
1386
1387 pr_warn("Boot CPU (id %d) not listed by BIOS\n", cpu);
1388
1389 /* Make sure boot cpu is enumerated */
1390 if (apic->cpu_present_to_apicid(0) == BAD_APICID &&
1391 apic->apic_id_valid(apicid))
1392 generic_processor_info(apicid, boot_cpu_apic_version);
1393 }
1394
1395 if (!num_processors)
1396 num_processors = 1;
1397 }
1398
1399 i = setup_max_cpus ?: 1;
1400 if (setup_possible_cpus == -1) {
1401 possible = num_processors;
1402#ifdef CONFIG_HOTPLUG_CPU
1403 if (setup_max_cpus)
1404 possible += disabled_cpus;
1405#else
1406 if (possible > i)
1407 possible = i;
1408#endif
1409 } else
1410 possible = setup_possible_cpus;
1411
1412 total_cpus = max_t(int, possible, num_processors + disabled_cpus);
1413
1414 /* nr_cpu_ids could be reduced via nr_cpus= */
1415 if (possible > nr_cpu_ids) {
1416 pr_warn("%d Processors exceeds NR_CPUS limit of %u\n",
1417 possible, nr_cpu_ids);
1418 possible = nr_cpu_ids;
1419 }
1420
1421#ifdef CONFIG_HOTPLUG_CPU
1422 if (!setup_max_cpus)
1423#endif
1424 if (possible > i) {
1425 pr_warn("%d Processors exceeds max_cpus limit of %u\n",
1426 possible, setup_max_cpus);
1427 possible = i;
1428 }
1429
1430 nr_cpu_ids = possible;
1431
1432 pr_info("Allowing %d CPUs, %d hotplug CPUs\n",
1433 possible, max_t(int, possible - num_processors, 0));
1434
1435 reset_cpu_possible_mask();
1436
1437 for (i = 0; i < possible; i++)
1438 set_cpu_possible(i, true);
1439}
1440
1441#ifdef CONFIG_HOTPLUG_CPU
1442
1443/* Recompute SMT state for all CPUs on offline */
1444static void recompute_smt_state(void)
1445{
1446 int max_threads, cpu;
1447
1448 max_threads = 0;
1449 for_each_online_cpu (cpu) {
1450 int threads = cpumask_weight(topology_sibling_cpumask(cpu));
1451
1452 if (threads > max_threads)
1453 max_threads = threads;
1454 }
1455 __max_smt_threads = max_threads;
1456}
1457
1458static void remove_siblinginfo(int cpu)
1459{
1460 int sibling;
1461 struct cpuinfo_x86 *c = &cpu_data(cpu);
1462
1463 for_each_cpu(sibling, topology_core_cpumask(cpu)) {
1464 cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
1465 /*/
1466 * last thread sibling in this cpu core going down
1467 */
1468 if (cpumask_weight(topology_sibling_cpumask(cpu)) == 1)
1469 cpu_data(sibling).booted_cores--;
1470 }
1471
1472 for_each_cpu(sibling, topology_sibling_cpumask(cpu))
1473 cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
1474 for_each_cpu(sibling, cpu_llc_shared_mask(cpu))
1475 cpumask_clear_cpu(cpu, cpu_llc_shared_mask(sibling));
1476 cpumask_clear(cpu_llc_shared_mask(cpu));
1477 cpumask_clear(topology_sibling_cpumask(cpu));
1478 cpumask_clear(topology_core_cpumask(cpu));
1479 c->cpu_core_id = 0;
1480 c->booted_cores = 0;
1481 cpumask_clear_cpu(cpu, cpu_sibling_setup_mask);
1482 recompute_smt_state();
1483}
1484
1485static void remove_cpu_from_maps(int cpu)
1486{
1487 set_cpu_online(cpu, false);
1488 cpumask_clear_cpu(cpu, cpu_callout_mask);
1489 cpumask_clear_cpu(cpu, cpu_callin_mask);
1490 /* was set by cpu_init() */
1491 cpumask_clear_cpu(cpu, cpu_initialized_mask);
1492 numa_remove_cpu(cpu);
1493}
1494
1495void cpu_disable_common(void)
1496{
1497 int cpu = smp_processor_id();
1498
1499 remove_siblinginfo(cpu);
1500
1501 /* It's now safe to remove this processor from the online map */
1502 lock_vector_lock();
1503 remove_cpu_from_maps(cpu);
1504 unlock_vector_lock();
1505 fixup_irqs();
1506 lapic_offline();
1507}
1508
1509int native_cpu_disable(void)
1510{
1511 int ret;
1512
1513 ret = lapic_can_unplug_cpu();
1514 if (ret)
1515 return ret;
1516
1517 clear_local_APIC();
1518 cpu_disable_common();
1519
1520 return 0;
1521}
1522
1523int common_cpu_die(unsigned int cpu)
1524{
1525 int ret = 0;
1526
1527 /* We don't do anything here: idle task is faking death itself. */
1528
1529 /* They ack this in play_dead() by setting CPU_DEAD */
1530 if (cpu_wait_death(cpu, 5)) {
1531 if (system_state == SYSTEM_RUNNING)
1532 pr_info("CPU %u is now offline\n", cpu);
1533 } else {
1534 pr_err("CPU %u didn't die...\n", cpu);
1535 ret = -1;
1536 }
1537
1538 return ret;
1539}
1540
1541void native_cpu_die(unsigned int cpu)
1542{
1543 common_cpu_die(cpu);
1544}
1545
1546void play_dead_common(void)
1547{
1548 idle_task_exit();
1549
1550 /* Ack it */
1551 (void)cpu_report_death();
1552
1553 /*
1554 * With physical CPU hotplug, we should halt the cpu
1555 */
1556 local_irq_disable();
1557}
1558
1559static bool wakeup_cpu0(void)
1560{
1561 if (smp_processor_id() == 0 && enable_start_cpu0)
1562 return true;
1563
1564 return false;
1565}
1566
1567/*
1568 * We need to flush the caches before going to sleep, lest we have
1569 * dirty data in our caches when we come back up.
1570 */
1571static inline void mwait_play_dead(void)
1572{
1573 unsigned int eax, ebx, ecx, edx;
1574 unsigned int highest_cstate = 0;
1575 unsigned int highest_subcstate = 0;
1576 void *mwait_ptr;
1577 int i;
1578
1579 if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)
1580 return;
1581 if (!this_cpu_has(X86_FEATURE_MWAIT))
1582 return;
1583 if (!this_cpu_has(X86_FEATURE_CLFLUSH))
1584 return;
1585 if (__this_cpu_read(cpu_info.cpuid_level) < CPUID_MWAIT_LEAF)
1586 return;
1587
1588 eax = CPUID_MWAIT_LEAF;
1589 ecx = 0;
1590 native_cpuid(&eax, &ebx, &ecx, &edx);
1591
1592 /*
1593 * eax will be 0 if EDX enumeration is not valid.
1594 * Initialized below to cstate, sub_cstate value when EDX is valid.
1595 */
1596 if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) {
1597 eax = 0;
1598 } else {
1599 edx >>= MWAIT_SUBSTATE_SIZE;
1600 for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) {
1601 if (edx & MWAIT_SUBSTATE_MASK) {
1602 highest_cstate = i;
1603 highest_subcstate = edx & MWAIT_SUBSTATE_MASK;
1604 }
1605 }
1606 eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) |
1607 (highest_subcstate - 1);
1608 }
1609
1610 /*
1611 * This should be a memory location in a cache line which is
1612 * unlikely to be touched by other processors. The actual
1613 * content is immaterial as it is not actually modified in any way.
1614 */
1615 mwait_ptr = ¤t_thread_info()->flags;
1616
1617 wbinvd();
1618
1619 while (1) {
1620 /*
1621 * The CLFLUSH is a workaround for erratum AAI65 for
1622 * the Xeon 7400 series. It's not clear it is actually
1623 * needed, but it should be harmless in either case.
1624 * The WBINVD is insufficient due to the spurious-wakeup
1625 * case where we return around the loop.
1626 */
1627 mb();
1628 clflush(mwait_ptr);
1629 mb();
1630 __monitor(mwait_ptr, 0, 0);
1631 mb();
1632 __mwait(eax, 0);
1633 /*
1634 * If NMI wants to wake up CPU0, start CPU0.
1635 */
1636 if (wakeup_cpu0())
1637 start_cpu0();
1638 }
1639}
1640
1641void hlt_play_dead(void)
1642{
1643 if (__this_cpu_read(cpu_info.x86) >= 4)
1644 wbinvd();
1645
1646 while (1) {
1647 native_halt();
1648 /*
1649 * If NMI wants to wake up CPU0, start CPU0.
1650 */
1651 if (wakeup_cpu0())
1652 start_cpu0();
1653 }
1654}
1655
1656void native_play_dead(void)
1657{
1658 play_dead_common();
1659 tboot_shutdown(TB_SHUTDOWN_WFS);
1660
1661 mwait_play_dead(); /* Only returns on failure */
1662 if (cpuidle_play_dead())
1663 hlt_play_dead();
1664}
1665
1666#else /* ... !CONFIG_HOTPLUG_CPU */
1667int native_cpu_disable(void)
1668{
1669 return -ENOSYS;
1670}
1671
1672void native_cpu_die(unsigned int cpu)
1673{
1674 /* We said "no" in __cpu_disable */
1675 BUG();
1676}
1677
1678void native_play_dead(void)
1679{
1680 BUG();
1681}
1682
1683#endif