2 * SMP initialisation and IPI support
3 * Based on arch/arm/kernel/smp.c
5 * Copyright (C) 2012 ARM Ltd.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
20 #include <linux/acpi.h>
21 #include <linux/arm_sdei.h>
22 #include <linux/delay.h>
23 #include <linux/init.h>
24 #include <linux/spinlock.h>
25 #include <linux/sched/mm.h>
26 #include <linux/sched/hotplug.h>
27 #include <linux/sched/task_stack.h>
28 #include <linux/interrupt.h>
29 #include <linux/cache.h>
30 #include <linux/profile.h>
31 #include <linux/errno.h>
33 #include <linux/err.h>
34 #include <linux/cpu.h>
35 #include <linux/smp.h>
36 #include <linux/seq_file.h>
37 #include <linux/irq.h>
38 #include <linux/percpu.h>
39 #include <linux/clockchips.h>
40 #include <linux/completion.h>
42 #include <linux/irq_work.h>
43 #include <linux/kexec.h>
45 #include <asm/alternative.h>
46 #include <asm/atomic.h>
47 #include <asm/cacheflush.h>
49 #include <asm/cputype.h>
50 #include <asm/cpu_ops.h>
51 #include <asm/daifflags.h>
52 #include <asm/mmu_context.h>
54 #include <asm/pgtable.h>
55 #include <asm/pgalloc.h>
56 #include <asm/processor.h>
57 #include <asm/smp_plat.h>
58 #include <asm/sections.h>
59 #include <asm/tlbflush.h>
60 #include <asm/ptrace.h>
63 #define CREATE_TRACE_POINTS
64 #include <trace/events/ipi.h>
66 DEFINE_PER_CPU_READ_MOSTLY(int, cpu_number);
67 EXPORT_PER_CPU_SYMBOL(cpu_number);
70 * as from 2.5, kernels no longer have an init_tasks structure
71 * so we need some other way of telling a new secondary core
72 * where to place its SVC stack
74 struct secondary_data secondary_data;
75 /* Number of CPUs which aren't online, but looping in kernel text. */
76 int cpus_stuck_in_kernel;
88 #ifdef CONFIG_HOTPLUG_CPU
89 static int op_cpu_kill(unsigned int cpu);
91 static inline int op_cpu_kill(unsigned int cpu)
99 * Boot a secondary CPU, and assign it the specified idle task.
100 * This also gives us the initial stack to use for this CPU.
102 static int boot_secondary(unsigned int cpu, struct task_struct *idle)
104 if (cpu_ops[cpu]->cpu_boot)
105 return cpu_ops[cpu]->cpu_boot(cpu);
110 static DECLARE_COMPLETION(cpu_running);
112 int __cpu_up(unsigned int cpu, struct task_struct *idle)
118 * We need to tell the secondary core where to find its stack and the
121 secondary_data.task = idle;
122 secondary_data.stack = task_stack_page(idle) + THREAD_SIZE;
123 update_cpu_boot_status(CPU_MMU_OFF);
124 __flush_dcache_area(&secondary_data, sizeof(secondary_data));
127 * Now bring the CPU into our world.
129 ret = boot_secondary(cpu, idle);
132 * CPU was successfully started, wait for it to come online or
135 wait_for_completion_timeout(&cpu_running,
136 msecs_to_jiffies(1000));
138 if (!cpu_online(cpu)) {
139 pr_crit("CPU%u: failed to come online\n", cpu);
143 pr_err("CPU%u: failed to boot: %d\n", cpu, ret);
146 secondary_data.task = NULL;
147 secondary_data.stack = NULL;
148 status = READ_ONCE(secondary_data.status);
151 if (status == CPU_MMU_OFF)
152 status = READ_ONCE(__early_cpu_boot_status);
156 pr_err("CPU%u: failed in unknown state : 0x%lx\n",
160 if (!op_cpu_kill(cpu)) {
161 pr_crit("CPU%u: died during early boot\n", cpu);
165 pr_crit("CPU%u: may not have shut down cleanly\n", cpu);
166 case CPU_STUCK_IN_KERNEL:
167 pr_crit("CPU%u: is stuck in kernel\n", cpu);
168 cpus_stuck_in_kernel++;
170 case CPU_PANIC_KERNEL:
171 panic("CPU%u detected unsupported configuration\n", cpu);
179 * This is the secondary CPU boot entry. We're using this CPUs
180 * idle thread stack, but a set of temporary page tables.
182 asmlinkage notrace void secondary_start_kernel(void)
184 u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
185 struct mm_struct *mm = &init_mm;
188 cpu = task_cpu(current);
189 set_my_cpu_offset(per_cpu_offset(cpu));
192 * All kernel threads share the same mm context; grab a
193 * reference and switch to it.
196 current->active_mm = mm;
199 * TTBR0 is only used for the identity mapping at this stage. Make it
200 * point to zero page to avoid speculatively fetching new entries.
202 cpu_uninstall_idmap();
205 trace_hardirqs_off();
208 * If the system has established the capabilities, make sure
209 * this CPU ticks all of those. If it doesn't, the CPU will
210 * fail to come online.
212 check_local_cpu_capabilities();
214 if (cpu_ops[cpu]->cpu_postboot)
215 cpu_ops[cpu]->cpu_postboot();
218 * Log the CPU info before it is marked online and might get read.
223 * Enable GIC and timers.
225 notify_cpu_starting(cpu);
227 store_cpu_topology(cpu);
231 * OK, now it's safe to let the boot CPU continue. Wait for
232 * the CPU migration code to notice that the CPU is online
233 * before we continue.
235 pr_info("CPU%u: Booted secondary processor 0x%010lx [0x%08x]\n",
236 cpu, (unsigned long)mpidr,
238 update_cpu_boot_status(CPU_BOOT_SUCCESS);
239 set_cpu_online(cpu, true);
240 complete(&cpu_running);
242 local_daif_restore(DAIF_PROCCTX);
245 * OK, it's off to the idle thread for us
247 cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
250 #ifdef CONFIG_HOTPLUG_CPU
251 static int op_cpu_disable(unsigned int cpu)
254 * If we don't have a cpu_die method, abort before we reach the point
255 * of no return. CPU0 may not have an cpu_ops, so test for it.
257 if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_die)
261 * We may need to abort a hot unplug for some other mechanism-specific
264 if (cpu_ops[cpu]->cpu_disable)
265 return cpu_ops[cpu]->cpu_disable(cpu);
271 * __cpu_disable runs on the processor to be shutdown.
273 int __cpu_disable(void)
275 unsigned int cpu = smp_processor_id();
278 ret = op_cpu_disable(cpu);
282 remove_cpu_topology(cpu);
283 numa_remove_cpu(cpu);
286 * Take this CPU offline. Once we clear this, we can't return,
287 * and we must not schedule until we're ready to give up the cpu.
289 set_cpu_online(cpu, false);
292 * OK - migrate IRQs away from this CPU
294 irq_migrate_all_off_this_cpu();
299 static int op_cpu_kill(unsigned int cpu)
302 * If we have no means of synchronising with the dying CPU, then assume
303 * that it is really dead. We can only wait for an arbitrary length of
304 * time and hope that it's dead, so let's skip the wait and just hope.
306 if (!cpu_ops[cpu]->cpu_kill)
309 return cpu_ops[cpu]->cpu_kill(cpu);
313 * called on the thread which is asking for a CPU to be shutdown -
314 * waits until shutdown has completed, or it is timed out.
316 void __cpu_die(unsigned int cpu)
320 if (!cpu_wait_death(cpu, 5)) {
321 pr_crit("CPU%u: cpu didn't die\n", cpu);
324 pr_notice("CPU%u: shutdown\n", cpu);
327 * Now that the dying CPU is beyond the point of no return w.r.t.
328 * in-kernel synchronisation, try to get the firwmare to help us to
329 * verify that it has really left the kernel before we consider
330 * clobbering anything it might still be using.
332 err = op_cpu_kill(cpu);
334 pr_warn("CPU%d may not have shut down cleanly: %d\n",
339 * Called from the idle thread for the CPU which has been shutdown.
344 unsigned int cpu = smp_processor_id();
350 /* Tell __cpu_die() that this CPU is now safe to dispose of */
351 (void)cpu_report_death();
354 * Actually shutdown the CPU. This must never fail. The specific hotplug
355 * mechanism must perform all required cache maintenance to ensure that
356 * no dirty lines are lost in the process of shutting down the CPU.
358 cpu_ops[cpu]->cpu_die(cpu);
365 * Kill the calling secondary CPU, early in bringup before it is turned
368 void cpu_die_early(void)
370 int cpu = smp_processor_id();
372 pr_crit("CPU%d: will not boot\n", cpu);
374 /* Mark this CPU absent */
375 set_cpu_present(cpu, 0);
377 #ifdef CONFIG_HOTPLUG_CPU
378 update_cpu_boot_status(CPU_KILL_ME);
379 /* Check if we can park ourselves */
380 if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_die)
381 cpu_ops[cpu]->cpu_die(cpu);
383 update_cpu_boot_status(CPU_STUCK_IN_KERNEL);
388 static void __init hyp_mode_check(void)
390 if (is_hyp_mode_available())
391 pr_info("CPU: All CPU(s) started at EL2\n");
392 else if (is_hyp_mode_mismatched())
393 WARN_TAINT(1, TAINT_CPU_OUT_OF_SPEC,
394 "CPU: CPUs started in inconsistent modes");
396 pr_info("CPU: All CPU(s) started at EL1\n");
399 void __init smp_cpus_done(unsigned int max_cpus)
401 pr_info("SMP: Total of %d processors activated.\n", num_online_cpus());
402 setup_cpu_features();
404 apply_alternatives_all();
405 mark_linear_text_alias_ro();
408 void __init smp_prepare_boot_cpu(void)
410 set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
412 * Initialise the static keys early as they may be enabled by the
416 cpuinfo_store_boot_cpu();
419 static u64 __init of_get_cpu_mpidr(struct device_node *dn)
425 * A cpu node with missing "reg" property is
426 * considered invalid to build a cpu_logical_map
429 cell = of_get_property(dn, "reg", NULL);
431 pr_err("%pOF: missing reg property\n", dn);
435 hwid = of_read_number(cell, of_n_addr_cells(dn));
437 * Non affinity bits must be set to 0 in the DT
439 if (hwid & ~MPIDR_HWID_BITMASK) {
440 pr_err("%pOF: invalid reg property\n", dn);
447 * Duplicate MPIDRs are a recipe for disaster. Scan all initialized
448 * entries and check for duplicates. If any is found just ignore the
449 * cpu. cpu_logical_map was initialized to INVALID_HWID to avoid
450 * matching valid MPIDR values.
452 static bool __init is_mpidr_duplicate(unsigned int cpu, u64 hwid)
456 for (i = 1; (i < cpu) && (i < NR_CPUS); i++)
457 if (cpu_logical_map(i) == hwid)
463 * Initialize cpu operations for a logical cpu and
464 * set it in the possible mask on success
466 static int __init smp_cpu_setup(int cpu)
468 if (cpu_read_ops(cpu))
471 if (cpu_ops[cpu]->cpu_init(cpu))
474 set_cpu_possible(cpu, true);
479 static bool bootcpu_valid __initdata;
480 static unsigned int cpu_count = 1;
483 static struct acpi_madt_generic_interrupt cpu_madt_gicc[NR_CPUS];
485 struct acpi_madt_generic_interrupt *acpi_cpu_get_madt_gicc(int cpu)
487 return &cpu_madt_gicc[cpu];
491 * acpi_map_gic_cpu_interface - parse processor MADT entry
493 * Carry out sanity checks on MADT processor entry and initialize
494 * cpu_logical_map on success
497 acpi_map_gic_cpu_interface(struct acpi_madt_generic_interrupt *processor)
499 u64 hwid = processor->arm_mpidr;
501 if (!(processor->flags & ACPI_MADT_ENABLED)) {
502 pr_debug("skipping disabled CPU entry with 0x%llx MPIDR\n", hwid);
506 if (hwid & ~MPIDR_HWID_BITMASK || hwid == INVALID_HWID) {
507 pr_err("skipping CPU entry with invalid MPIDR 0x%llx\n", hwid);
511 if (is_mpidr_duplicate(cpu_count, hwid)) {
512 pr_err("duplicate CPU MPIDR 0x%llx in MADT\n", hwid);
516 /* Check if GICC structure of boot CPU is available in the MADT */
517 if (cpu_logical_map(0) == hwid) {
519 pr_err("duplicate boot CPU MPIDR: 0x%llx in MADT\n",
523 bootcpu_valid = true;
524 cpu_madt_gicc[0] = *processor;
528 if (cpu_count >= NR_CPUS)
531 /* map the logical cpu id to cpu MPIDR */
532 cpu_logical_map(cpu_count) = hwid;
534 cpu_madt_gicc[cpu_count] = *processor;
537 * Set-up the ACPI parking protocol cpu entries
538 * while initializing the cpu_logical_map to
539 * avoid parsing MADT entries multiple times for
540 * nothing (ie a valid cpu_logical_map entry should
541 * contain a valid parking protocol data set to
542 * initialize the cpu if the parking protocol is
543 * the only available enable method).
545 acpi_set_mailbox_entry(cpu_count, processor);
551 acpi_parse_gic_cpu_interface(struct acpi_subtable_header *header,
552 const unsigned long end)
554 struct acpi_madt_generic_interrupt *processor;
556 processor = (struct acpi_madt_generic_interrupt *)header;
557 if (BAD_MADT_GICC_ENTRY(processor, end))
560 acpi_table_print_madt_entry(header);
562 acpi_map_gic_cpu_interface(processor);
567 static void __init acpi_parse_and_init_cpus(void)
572 * do a walk of MADT to determine how many CPUs
573 * we have including disabled CPUs, and get information
574 * we need for SMP init.
576 acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
577 acpi_parse_gic_cpu_interface, 0);
580 * In ACPI, SMP and CPU NUMA information is provided in separate
581 * static tables, namely the MADT and the SRAT.
583 * Thus, it is simpler to first create the cpu logical map through
584 * an MADT walk and then map the logical cpus to their node ids
587 acpi_map_cpus_to_nodes();
589 for (i = 0; i < nr_cpu_ids; i++)
590 early_map_cpu_to_node(i, acpi_numa_get_nid(i));
593 #define acpi_parse_and_init_cpus(...) do { } while (0)
597 * Enumerate the possible CPU set from the device tree and build the
598 * cpu logical map array containing MPIDR values related to logical
599 * cpus. Assumes that cpu_logical_map(0) has already been initialized.
601 static void __init of_parse_and_init_cpus(void)
603 struct device_node *dn;
605 for_each_of_cpu_node(dn) {
606 u64 hwid = of_get_cpu_mpidr(dn);
608 if (hwid == INVALID_HWID)
611 if (is_mpidr_duplicate(cpu_count, hwid)) {
612 pr_err("%pOF: duplicate cpu reg properties in the DT\n",
618 * The numbering scheme requires that the boot CPU
619 * must be assigned logical id 0. Record it so that
620 * the logical map built from DT is validated and can
623 if (hwid == cpu_logical_map(0)) {
625 pr_err("%pOF: duplicate boot cpu reg property in DT\n",
630 bootcpu_valid = true;
631 early_map_cpu_to_node(0, of_node_to_nid(dn));
634 * cpu_logical_map has already been
635 * initialized and the boot cpu doesn't need
636 * the enable-method so continue without
642 if (cpu_count >= NR_CPUS)
645 pr_debug("cpu logical map 0x%llx\n", hwid);
646 cpu_logical_map(cpu_count) = hwid;
648 early_map_cpu_to_node(cpu_count, of_node_to_nid(dn));
655 * Enumerate the possible CPU set from the device tree or ACPI and build the
656 * cpu logical map array containing MPIDR values related to logical
657 * cpus. Assumes that cpu_logical_map(0) has already been initialized.
659 void __init smp_init_cpus(void)
664 of_parse_and_init_cpus();
666 acpi_parse_and_init_cpus();
668 if (cpu_count > nr_cpu_ids)
669 pr_warn("Number of cores (%d) exceeds configured maximum of %u - clipping\n",
670 cpu_count, nr_cpu_ids);
672 if (!bootcpu_valid) {
673 pr_err("missing boot CPU MPIDR, not enabling secondaries\n");
678 * We need to set the cpu_logical_map entries before enabling
679 * the cpus so that cpu processor description entries (DT cpu nodes
680 * and ACPI MADT entries) can be retrieved by matching the cpu hwid
681 * with entries in cpu_logical_map while initializing the cpus.
682 * If the cpu set-up fails, invalidate the cpu_logical_map entry.
684 for (i = 1; i < nr_cpu_ids; i++) {
685 if (cpu_logical_map(i) != INVALID_HWID) {
686 if (smp_cpu_setup(i))
687 cpu_logical_map(i) = INVALID_HWID;
692 void __init smp_prepare_cpus(unsigned int max_cpus)
696 unsigned int this_cpu;
700 this_cpu = smp_processor_id();
701 store_cpu_topology(this_cpu);
702 numa_store_cpu_info(this_cpu);
703 numa_add_cpu(this_cpu);
706 * If UP is mandated by "nosmp" (which implies "maxcpus=0"), don't set
707 * secondary CPUs present.
713 * Initialise the present map (which describes the set of CPUs
714 * actually populated at the present time) and release the
715 * secondaries from the bootloader.
717 for_each_possible_cpu(cpu) {
719 per_cpu(cpu_number, cpu) = cpu;
721 if (cpu == smp_processor_id())
727 err = cpu_ops[cpu]->cpu_prepare(cpu);
731 set_cpu_present(cpu, true);
732 numa_store_cpu_info(cpu);
736 void (*__smp_cross_call)(const struct cpumask *, unsigned int);
738 void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int))
740 __smp_cross_call = fn;
743 static const char *ipi_types[NR_IPI] __tracepoint_string = {
744 #define S(x,s) [x] = s
745 S(IPI_RESCHEDULE, "Rescheduling interrupts"),
746 S(IPI_CALL_FUNC, "Function call interrupts"),
747 S(IPI_CPU_STOP, "CPU stop interrupts"),
748 S(IPI_CPU_CRASH_STOP, "CPU stop (for crash dump) interrupts"),
749 S(IPI_TIMER, "Timer broadcast interrupts"),
750 S(IPI_IRQ_WORK, "IRQ work interrupts"),
751 S(IPI_WAKEUP, "CPU wake-up interrupts"),
754 static void smp_cross_call(const struct cpumask *target, unsigned int ipinr)
756 trace_ipi_raise(target, ipi_types[ipinr]);
757 __smp_cross_call(target, ipinr);
760 void show_ipi_list(struct seq_file *p, int prec)
764 for (i = 0; i < NR_IPI; i++) {
765 seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
766 prec >= 4 ? " " : "");
767 for_each_online_cpu(cpu)
768 seq_printf(p, "%10u ",
769 __get_irq_stat(cpu, ipi_irqs[i]));
770 seq_printf(p, " %s\n", ipi_types[i]);
774 u64 smp_irq_stat_cpu(unsigned int cpu)
779 for (i = 0; i < NR_IPI; i++)
780 sum += __get_irq_stat(cpu, ipi_irqs[i]);
785 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
787 smp_cross_call(mask, IPI_CALL_FUNC);
790 void arch_send_call_function_single_ipi(int cpu)
792 smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC);
795 #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
796 void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
798 smp_cross_call(mask, IPI_WAKEUP);
802 #ifdef CONFIG_IRQ_WORK
803 void arch_irq_work_raise(void)
805 if (__smp_cross_call)
806 smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK);
811 * ipi_cpu_stop - handle IPI from smp_send_stop()
813 static void ipi_cpu_stop(unsigned int cpu)
815 set_cpu_online(cpu, false);
818 sdei_mask_local_cpu();
824 #ifdef CONFIG_KEXEC_CORE
825 static atomic_t waiting_for_crash_ipi = ATOMIC_INIT(0);
828 static void ipi_cpu_crash_stop(unsigned int cpu, struct pt_regs *regs)
830 #ifdef CONFIG_KEXEC_CORE
831 crash_save_cpu(regs, cpu);
833 atomic_dec(&waiting_for_crash_ipi);
836 sdei_mask_local_cpu();
838 #ifdef CONFIG_HOTPLUG_CPU
839 if (cpu_ops[cpu]->cpu_die)
840 cpu_ops[cpu]->cpu_die(cpu);
849 * Main handler for inter-processor interrupts
851 void handle_IPI(int ipinr, struct pt_regs *regs)
853 unsigned int cpu = smp_processor_id();
854 struct pt_regs *old_regs = set_irq_regs(regs);
856 if ((unsigned)ipinr < NR_IPI) {
857 trace_ipi_entry_rcuidle(ipi_types[ipinr]);
858 __inc_irq_stat(cpu, ipi_irqs[ipinr]);
868 generic_smp_call_function_interrupt();
878 case IPI_CPU_CRASH_STOP:
879 if (IS_ENABLED(CONFIG_KEXEC_CORE)) {
881 ipi_cpu_crash_stop(cpu, regs);
887 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
890 tick_receive_broadcast();
895 #ifdef CONFIG_IRQ_WORK
903 #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
905 WARN_ONCE(!acpi_parking_protocol_valid(cpu),
906 "CPU%u: Wake-up IPI outside the ACPI parking protocol\n",
912 pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr);
916 if ((unsigned)ipinr < NR_IPI)
917 trace_ipi_exit_rcuidle(ipi_types[ipinr]);
918 set_irq_regs(old_regs);
921 void smp_send_reschedule(int cpu)
923 smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE);
926 #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
927 void tick_broadcast(const struct cpumask *mask)
929 smp_cross_call(mask, IPI_TIMER);
933 void smp_send_stop(void)
935 unsigned long timeout;
937 if (num_online_cpus() > 1) {
940 cpumask_copy(&mask, cpu_online_mask);
941 cpumask_clear_cpu(smp_processor_id(), &mask);
943 if (system_state <= SYSTEM_RUNNING)
944 pr_crit("SMP: stopping secondary CPUs\n");
945 smp_cross_call(&mask, IPI_CPU_STOP);
948 /* Wait up to one second for other CPUs to stop */
949 timeout = USEC_PER_SEC;
950 while (num_online_cpus() > 1 && timeout--)
953 if (num_online_cpus() > 1)
954 pr_warning("SMP: failed to stop secondary CPUs %*pbl\n",
955 cpumask_pr_args(cpu_online_mask));
957 sdei_mask_local_cpu();
960 #ifdef CONFIG_KEXEC_CORE
961 void crash_smp_send_stop(void)
963 static int cpus_stopped;
965 unsigned long timeout;
968 * This function can be called twice in panic path, but obviously
969 * we execute this only once.
976 if (num_online_cpus() == 1) {
977 sdei_mask_local_cpu();
981 cpumask_copy(&mask, cpu_online_mask);
982 cpumask_clear_cpu(smp_processor_id(), &mask);
984 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
986 pr_crit("SMP: stopping secondary CPUs\n");
987 smp_cross_call(&mask, IPI_CPU_CRASH_STOP);
989 /* Wait up to one second for other CPUs to stop */
990 timeout = USEC_PER_SEC;
991 while ((atomic_read(&waiting_for_crash_ipi) > 0) && timeout--)
994 if (atomic_read(&waiting_for_crash_ipi) > 0)
995 pr_warning("SMP: failed to stop secondary CPUs %*pbl\n",
996 cpumask_pr_args(&mask));
998 sdei_mask_local_cpu();
1001 bool smp_crash_stop_failed(void)
1003 return (atomic_read(&waiting_for_crash_ipi) > 0);
1008 * not supported here
1010 int setup_profiling_timer(unsigned int multiplier)
1015 static bool have_cpu_die(void)
1017 #ifdef CONFIG_HOTPLUG_CPU
1018 int any_cpu = raw_smp_processor_id();
1020 if (cpu_ops[any_cpu] && cpu_ops[any_cpu]->cpu_die)
1026 bool cpus_are_stuck_in_kernel(void)
1028 bool smp_spin_tables = (num_possible_cpus() > 1 && !have_cpu_die());
1030 return !!cpus_stuck_in_kernel || smp_spin_tables;