v4.19.13 snapshot.
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
new file mode 100644
index 0000000..25fcd22
--- /dev/null
+++ b/arch/arm64/kernel/smp.c
@@ -0,0 +1,1031 @@
+/*
+ * SMP initialisation and IPI support
+ * Based on arch/arm/kernel/smp.c
+ *
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/acpi.h>
+#include <linux/arm_sdei.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/hotplug.h>
+#include <linux/sched/task_stack.h>
+#include <linux/interrupt.h>
+#include <linux/cache.h>
+#include <linux/profile.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/err.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/seq_file.h>
+#include <linux/irq.h>
+#include <linux/percpu.h>
+#include <linux/clockchips.h>
+#include <linux/completion.h>
+#include <linux/of.h>
+#include <linux/irq_work.h>
+#include <linux/kexec.h>
+
+#include <asm/alternative.h>
+#include <asm/atomic.h>
+#include <asm/cacheflush.h>
+#include <asm/cpu.h>
+#include <asm/cputype.h>
+#include <asm/cpu_ops.h>
+#include <asm/daifflags.h>
+#include <asm/mmu_context.h>
+#include <asm/numa.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/processor.h>
+#include <asm/smp_plat.h>
+#include <asm/sections.h>
+#include <asm/tlbflush.h>
+#include <asm/ptrace.h>
+#include <asm/virt.h>
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/ipi.h>
+
+DEFINE_PER_CPU_READ_MOSTLY(int, cpu_number);
+EXPORT_PER_CPU_SYMBOL(cpu_number);
+
+/*
+ * as from 2.5, kernels no longer have an init_tasks structure
+ * so we need some other way of telling a new secondary core
+ * where to place its SVC stack
+ */
+struct secondary_data secondary_data;
+/* Number of CPUs which aren't online, but looping in kernel text. */
+int cpus_stuck_in_kernel;
+
+enum ipi_msg_type {
+ IPI_RESCHEDULE,
+ IPI_CALL_FUNC,
+ IPI_CPU_STOP,
+ IPI_CPU_CRASH_STOP,
+ IPI_TIMER,
+ IPI_IRQ_WORK,
+ IPI_WAKEUP
+};
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int op_cpu_kill(unsigned int cpu);
+#else
+static inline int op_cpu_kill(unsigned int cpu)
+{
+ return -ENOSYS;
+}
+#endif
+
+
+/*
+ * Boot a secondary CPU, and assign it the specified idle task.
+ * This also gives us the initial stack to use for this CPU.
+ */
+static int boot_secondary(unsigned int cpu, struct task_struct *idle)
+{
+ if (cpu_ops[cpu]->cpu_boot)
+ return cpu_ops[cpu]->cpu_boot(cpu);
+
+ return -EOPNOTSUPP;
+}
+
+static DECLARE_COMPLETION(cpu_running);
+
+int __cpu_up(unsigned int cpu, struct task_struct *idle)
+{
+ int ret;
+ long status;
+
+ /*
+ * We need to tell the secondary core where to find its stack and the
+ * page tables.
+ */
+ secondary_data.task = idle;
+ secondary_data.stack = task_stack_page(idle) + THREAD_SIZE;
+ update_cpu_boot_status(CPU_MMU_OFF);
+ __flush_dcache_area(&secondary_data, sizeof(secondary_data));
+
+ /*
+ * Now bring the CPU into our world.
+ */
+ ret = boot_secondary(cpu, idle);
+ if (ret == 0) {
+ /*
+ * CPU was successfully started, wait for it to come online or
+ * time out.
+ */
+ wait_for_completion_timeout(&cpu_running,
+ msecs_to_jiffies(1000));
+
+ if (!cpu_online(cpu)) {
+ pr_crit("CPU%u: failed to come online\n", cpu);
+ ret = -EIO;
+ }
+ } else {
+ pr_err("CPU%u: failed to boot: %d\n", cpu, ret);
+ }
+
+ secondary_data.task = NULL;
+ secondary_data.stack = NULL;
+ status = READ_ONCE(secondary_data.status);
+ if (ret && status) {
+
+ if (status == CPU_MMU_OFF)
+ status = READ_ONCE(__early_cpu_boot_status);
+
+ switch (status) {
+ default:
+ pr_err("CPU%u: failed in unknown state : 0x%lx\n",
+ cpu, status);
+ break;
+ case CPU_KILL_ME:
+ if (!op_cpu_kill(cpu)) {
+ pr_crit("CPU%u: died during early boot\n", cpu);
+ break;
+ }
+ /* Fall through */
+ pr_crit("CPU%u: may not have shut down cleanly\n", cpu);
+ case CPU_STUCK_IN_KERNEL:
+ pr_crit("CPU%u: is stuck in kernel\n", cpu);
+ cpus_stuck_in_kernel++;
+ break;
+ case CPU_PANIC_KERNEL:
+ panic("CPU%u detected unsupported configuration\n", cpu);
+ }
+ }
+
+ return ret;
+}
+
+/*
+ * This is the secondary CPU boot entry. We're using this CPUs
+ * idle thread stack, but a set of temporary page tables.
+ */
+asmlinkage notrace void secondary_start_kernel(void)
+{
+ u64 mpidr = read_cpuid_mpidr() & MPIDR_HWID_BITMASK;
+ struct mm_struct *mm = &init_mm;
+ unsigned int cpu;
+
+ cpu = task_cpu(current);
+ set_my_cpu_offset(per_cpu_offset(cpu));
+
+ /*
+ * All kernel threads share the same mm context; grab a
+ * reference and switch to it.
+ */
+ mmgrab(mm);
+ current->active_mm = mm;
+
+ /*
+ * TTBR0 is only used for the identity mapping at this stage. Make it
+ * point to zero page to avoid speculatively fetching new entries.
+ */
+ cpu_uninstall_idmap();
+
+ preempt_disable();
+ trace_hardirqs_off();
+
+ /*
+ * If the system has established the capabilities, make sure
+ * this CPU ticks all of those. If it doesn't, the CPU will
+ * fail to come online.
+ */
+ check_local_cpu_capabilities();
+
+ if (cpu_ops[cpu]->cpu_postboot)
+ cpu_ops[cpu]->cpu_postboot();
+
+ /*
+ * Log the CPU info before it is marked online and might get read.
+ */
+ cpuinfo_store_cpu();
+
+ /*
+ * Enable GIC and timers.
+ */
+ notify_cpu_starting(cpu);
+
+ store_cpu_topology(cpu);
+ numa_add_cpu(cpu);
+
+ /*
+ * OK, now it's safe to let the boot CPU continue. Wait for
+ * the CPU migration code to notice that the CPU is online
+ * before we continue.
+ */
+ pr_info("CPU%u: Booted secondary processor 0x%010lx [0x%08x]\n",
+ cpu, (unsigned long)mpidr,
+ read_cpuid_id());
+ update_cpu_boot_status(CPU_BOOT_SUCCESS);
+ set_cpu_online(cpu, true);
+ complete(&cpu_running);
+
+ local_daif_restore(DAIF_PROCCTX);
+
+ /*
+ * OK, it's off to the idle thread for us
+ */
+ cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int op_cpu_disable(unsigned int cpu)
+{
+ /*
+ * If we don't have a cpu_die method, abort before we reach the point
+ * of no return. CPU0 may not have an cpu_ops, so test for it.
+ */
+ if (!cpu_ops[cpu] || !cpu_ops[cpu]->cpu_die)
+ return -EOPNOTSUPP;
+
+ /*
+ * We may need to abort a hot unplug for some other mechanism-specific
+ * reason.
+ */
+ if (cpu_ops[cpu]->cpu_disable)
+ return cpu_ops[cpu]->cpu_disable(cpu);
+
+ return 0;
+}
+
+/*
+ * __cpu_disable runs on the processor to be shutdown.
+ */
+int __cpu_disable(void)
+{
+ unsigned int cpu = smp_processor_id();
+ int ret;
+
+ ret = op_cpu_disable(cpu);
+ if (ret)
+ return ret;
+
+ remove_cpu_topology(cpu);
+ numa_remove_cpu(cpu);
+
+ /*
+ * Take this CPU offline. Once we clear this, we can't return,
+ * and we must not schedule until we're ready to give up the cpu.
+ */
+ set_cpu_online(cpu, false);
+
+ /*
+ * OK - migrate IRQs away from this CPU
+ */
+ irq_migrate_all_off_this_cpu();
+
+ return 0;
+}
+
+static int op_cpu_kill(unsigned int cpu)
+{
+ /*
+ * If we have no means of synchronising with the dying CPU, then assume
+ * that it is really dead. We can only wait for an arbitrary length of
+ * time and hope that it's dead, so let's skip the wait and just hope.
+ */
+ if (!cpu_ops[cpu]->cpu_kill)
+ return 0;
+
+ return cpu_ops[cpu]->cpu_kill(cpu);
+}
+
+/*
+ * called on the thread which is asking for a CPU to be shutdown -
+ * waits until shutdown has completed, or it is timed out.
+ */
+void __cpu_die(unsigned int cpu)
+{
+ int err;
+
+ if (!cpu_wait_death(cpu, 5)) {
+ pr_crit("CPU%u: cpu didn't die\n", cpu);
+ return;
+ }
+ pr_notice("CPU%u: shutdown\n", cpu);
+
+ /*
+ * Now that the dying CPU is beyond the point of no return w.r.t.
+ * in-kernel synchronisation, try to get the firwmare to help us to
+ * verify that it has really left the kernel before we consider
+ * clobbering anything it might still be using.
+ */
+ err = op_cpu_kill(cpu);
+ if (err)
+ pr_warn("CPU%d may not have shut down cleanly: %d\n",
+ cpu, err);
+}
+
+/*
+ * Called from the idle thread for the CPU which has been shutdown.
+ *
+ */
+void cpu_die(void)
+{
+ unsigned int cpu = smp_processor_id();
+
+ idle_task_exit();
+
+ local_daif_mask();
+
+ /* Tell __cpu_die() that this CPU is now safe to dispose of */
+ (void)cpu_report_death();
+
+ /*
+ * Actually shutdown the CPU. This must never fail. The specific hotplug
+ * mechanism must perform all required cache maintenance to ensure that
+ * no dirty lines are lost in the process of shutting down the CPU.
+ */
+ cpu_ops[cpu]->cpu_die(cpu);
+
+ BUG();
+}
+#endif
+
+/*
+ * Kill the calling secondary CPU, early in bringup before it is turned
+ * online.
+ */
+void cpu_die_early(void)
+{
+ int cpu = smp_processor_id();
+
+ pr_crit("CPU%d: will not boot\n", cpu);
+
+ /* Mark this CPU absent */
+ set_cpu_present(cpu, 0);
+
+#ifdef CONFIG_HOTPLUG_CPU
+ update_cpu_boot_status(CPU_KILL_ME);
+ /* Check if we can park ourselves */
+ if (cpu_ops[cpu] && cpu_ops[cpu]->cpu_die)
+ cpu_ops[cpu]->cpu_die(cpu);
+#endif
+ update_cpu_boot_status(CPU_STUCK_IN_KERNEL);
+
+ cpu_park_loop();
+}
+
+static void __init hyp_mode_check(void)
+{
+ if (is_hyp_mode_available())
+ pr_info("CPU: All CPU(s) started at EL2\n");
+ else if (is_hyp_mode_mismatched())
+ WARN_TAINT(1, TAINT_CPU_OUT_OF_SPEC,
+ "CPU: CPUs started in inconsistent modes");
+ else
+ pr_info("CPU: All CPU(s) started at EL1\n");
+}
+
+void __init smp_cpus_done(unsigned int max_cpus)
+{
+ pr_info("SMP: Total of %d processors activated.\n", num_online_cpus());
+ setup_cpu_features();
+ hyp_mode_check();
+ apply_alternatives_all();
+ mark_linear_text_alias_ro();
+}
+
+void __init smp_prepare_boot_cpu(void)
+{
+ set_my_cpu_offset(per_cpu_offset(smp_processor_id()));
+ /*
+ * Initialise the static keys early as they may be enabled by the
+ * cpufeature code.
+ */
+ jump_label_init();
+ cpuinfo_store_boot_cpu();
+}
+
+static u64 __init of_get_cpu_mpidr(struct device_node *dn)
+{
+ const __be32 *cell;
+ u64 hwid;
+
+ /*
+ * A cpu node with missing "reg" property is
+ * considered invalid to build a cpu_logical_map
+ * entry.
+ */
+ cell = of_get_property(dn, "reg", NULL);
+ if (!cell) {
+ pr_err("%pOF: missing reg property\n", dn);
+ return INVALID_HWID;
+ }
+
+ hwid = of_read_number(cell, of_n_addr_cells(dn));
+ /*
+ * Non affinity bits must be set to 0 in the DT
+ */
+ if (hwid & ~MPIDR_HWID_BITMASK) {
+ pr_err("%pOF: invalid reg property\n", dn);
+ return INVALID_HWID;
+ }
+ return hwid;
+}
+
+/*
+ * Duplicate MPIDRs are a recipe for disaster. Scan all initialized
+ * entries and check for duplicates. If any is found just ignore the
+ * cpu. cpu_logical_map was initialized to INVALID_HWID to avoid
+ * matching valid MPIDR values.
+ */
+static bool __init is_mpidr_duplicate(unsigned int cpu, u64 hwid)
+{
+ unsigned int i;
+
+ for (i = 1; (i < cpu) && (i < NR_CPUS); i++)
+ if (cpu_logical_map(i) == hwid)
+ return true;
+ return false;
+}
+
+/*
+ * Initialize cpu operations for a logical cpu and
+ * set it in the possible mask on success
+ */
+static int __init smp_cpu_setup(int cpu)
+{
+ if (cpu_read_ops(cpu))
+ return -ENODEV;
+
+ if (cpu_ops[cpu]->cpu_init(cpu))
+ return -ENODEV;
+
+ set_cpu_possible(cpu, true);
+
+ return 0;
+}
+
+static bool bootcpu_valid __initdata;
+static unsigned int cpu_count = 1;
+
+#ifdef CONFIG_ACPI
+static struct acpi_madt_generic_interrupt cpu_madt_gicc[NR_CPUS];
+
+struct acpi_madt_generic_interrupt *acpi_cpu_get_madt_gicc(int cpu)
+{
+ return &cpu_madt_gicc[cpu];
+}
+
+/*
+ * acpi_map_gic_cpu_interface - parse processor MADT entry
+ *
+ * Carry out sanity checks on MADT processor entry and initialize
+ * cpu_logical_map on success
+ */
+static void __init
+acpi_map_gic_cpu_interface(struct acpi_madt_generic_interrupt *processor)
+{
+ u64 hwid = processor->arm_mpidr;
+
+ if (!(processor->flags & ACPI_MADT_ENABLED)) {
+ pr_debug("skipping disabled CPU entry with 0x%llx MPIDR\n", hwid);
+ return;
+ }
+
+ if (hwid & ~MPIDR_HWID_BITMASK || hwid == INVALID_HWID) {
+ pr_err("skipping CPU entry with invalid MPIDR 0x%llx\n", hwid);
+ return;
+ }
+
+ if (is_mpidr_duplicate(cpu_count, hwid)) {
+ pr_err("duplicate CPU MPIDR 0x%llx in MADT\n", hwid);
+ return;
+ }
+
+ /* Check if GICC structure of boot CPU is available in the MADT */
+ if (cpu_logical_map(0) == hwid) {
+ if (bootcpu_valid) {
+ pr_err("duplicate boot CPU MPIDR: 0x%llx in MADT\n",
+ hwid);
+ return;
+ }
+ bootcpu_valid = true;
+ cpu_madt_gicc[0] = *processor;
+ return;
+ }
+
+ if (cpu_count >= NR_CPUS)
+ return;
+
+ /* map the logical cpu id to cpu MPIDR */
+ cpu_logical_map(cpu_count) = hwid;
+
+ cpu_madt_gicc[cpu_count] = *processor;
+
+ /*
+ * Set-up the ACPI parking protocol cpu entries
+ * while initializing the cpu_logical_map to
+ * avoid parsing MADT entries multiple times for
+ * nothing (ie a valid cpu_logical_map entry should
+ * contain a valid parking protocol data set to
+ * initialize the cpu if the parking protocol is
+ * the only available enable method).
+ */
+ acpi_set_mailbox_entry(cpu_count, processor);
+
+ cpu_count++;
+}
+
+static int __init
+acpi_parse_gic_cpu_interface(struct acpi_subtable_header *header,
+ const unsigned long end)
+{
+ struct acpi_madt_generic_interrupt *processor;
+
+ processor = (struct acpi_madt_generic_interrupt *)header;
+ if (BAD_MADT_GICC_ENTRY(processor, end))
+ return -EINVAL;
+
+ acpi_table_print_madt_entry(header);
+
+ acpi_map_gic_cpu_interface(processor);
+
+ return 0;
+}
+
+static void __init acpi_parse_and_init_cpus(void)
+{
+ int i;
+
+ /*
+ * do a walk of MADT to determine how many CPUs
+ * we have including disabled CPUs, and get information
+ * we need for SMP init.
+ */
+ acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
+ acpi_parse_gic_cpu_interface, 0);
+
+ /*
+ * In ACPI, SMP and CPU NUMA information is provided in separate
+ * static tables, namely the MADT and the SRAT.
+ *
+ * Thus, it is simpler to first create the cpu logical map through
+ * an MADT walk and then map the logical cpus to their node ids
+ * as separate steps.
+ */
+ acpi_map_cpus_to_nodes();
+
+ for (i = 0; i < nr_cpu_ids; i++)
+ early_map_cpu_to_node(i, acpi_numa_get_nid(i));
+}
+#else
+#define acpi_parse_and_init_cpus(...) do { } while (0)
+#endif
+
+/*
+ * Enumerate the possible CPU set from the device tree and build the
+ * cpu logical map array containing MPIDR values related to logical
+ * cpus. Assumes that cpu_logical_map(0) has already been initialized.
+ */
+static void __init of_parse_and_init_cpus(void)
+{
+ struct device_node *dn;
+
+ for_each_node_by_type(dn, "cpu") {
+ u64 hwid = of_get_cpu_mpidr(dn);
+
+ if (hwid == INVALID_HWID)
+ goto next;
+
+ if (is_mpidr_duplicate(cpu_count, hwid)) {
+ pr_err("%pOF: duplicate cpu reg properties in the DT\n",
+ dn);
+ goto next;
+ }
+
+ /*
+ * The numbering scheme requires that the boot CPU
+ * must be assigned logical id 0. Record it so that
+ * the logical map built from DT is validated and can
+ * be used.
+ */
+ if (hwid == cpu_logical_map(0)) {
+ if (bootcpu_valid) {
+ pr_err("%pOF: duplicate boot cpu reg property in DT\n",
+ dn);
+ goto next;
+ }
+
+ bootcpu_valid = true;
+ early_map_cpu_to_node(0, of_node_to_nid(dn));
+
+ /*
+ * cpu_logical_map has already been
+ * initialized and the boot cpu doesn't need
+ * the enable-method so continue without
+ * incrementing cpu.
+ */
+ continue;
+ }
+
+ if (cpu_count >= NR_CPUS)
+ goto next;
+
+ pr_debug("cpu logical map 0x%llx\n", hwid);
+ cpu_logical_map(cpu_count) = hwid;
+
+ early_map_cpu_to_node(cpu_count, of_node_to_nid(dn));
+next:
+ cpu_count++;
+ }
+}
+
+/*
+ * Enumerate the possible CPU set from the device tree or ACPI and build the
+ * cpu logical map array containing MPIDR values related to logical
+ * cpus. Assumes that cpu_logical_map(0) has already been initialized.
+ */
+void __init smp_init_cpus(void)
+{
+ int i;
+
+ if (acpi_disabled)
+ of_parse_and_init_cpus();
+ else
+ acpi_parse_and_init_cpus();
+
+ if (cpu_count > nr_cpu_ids)
+ pr_warn("Number of cores (%d) exceeds configured maximum of %u - clipping\n",
+ cpu_count, nr_cpu_ids);
+
+ if (!bootcpu_valid) {
+ pr_err("missing boot CPU MPIDR, not enabling secondaries\n");
+ return;
+ }
+
+ /*
+ * We need to set the cpu_logical_map entries before enabling
+ * the cpus so that cpu processor description entries (DT cpu nodes
+ * and ACPI MADT entries) can be retrieved by matching the cpu hwid
+ * with entries in cpu_logical_map while initializing the cpus.
+ * If the cpu set-up fails, invalidate the cpu_logical_map entry.
+ */
+ for (i = 1; i < nr_cpu_ids; i++) {
+ if (cpu_logical_map(i) != INVALID_HWID) {
+ if (smp_cpu_setup(i))
+ cpu_logical_map(i) = INVALID_HWID;
+ }
+ }
+}
+
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+ int err;
+ unsigned int cpu;
+ unsigned int this_cpu;
+
+ init_cpu_topology();
+
+ this_cpu = smp_processor_id();
+ store_cpu_topology(this_cpu);
+ numa_store_cpu_info(this_cpu);
+ numa_add_cpu(this_cpu);
+
+ /*
+ * If UP is mandated by "nosmp" (which implies "maxcpus=0"), don't set
+ * secondary CPUs present.
+ */
+ if (max_cpus == 0)
+ return;
+
+ /*
+ * Initialise the present map (which describes the set of CPUs
+ * actually populated at the present time) and release the
+ * secondaries from the bootloader.
+ */
+ for_each_possible_cpu(cpu) {
+
+ per_cpu(cpu_number, cpu) = cpu;
+
+ if (cpu == smp_processor_id())
+ continue;
+
+ if (!cpu_ops[cpu])
+ continue;
+
+ err = cpu_ops[cpu]->cpu_prepare(cpu);
+ if (err)
+ continue;
+
+ set_cpu_present(cpu, true);
+ numa_store_cpu_info(cpu);
+ }
+}
+
+void (*__smp_cross_call)(const struct cpumask *, unsigned int);
+
+void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int))
+{
+ __smp_cross_call = fn;
+}
+
+static const char *ipi_types[NR_IPI] __tracepoint_string = {
+#define S(x,s) [x] = s
+ S(IPI_RESCHEDULE, "Rescheduling interrupts"),
+ S(IPI_CALL_FUNC, "Function call interrupts"),
+ S(IPI_CPU_STOP, "CPU stop interrupts"),
+ S(IPI_CPU_CRASH_STOP, "CPU stop (for crash dump) interrupts"),
+ S(IPI_TIMER, "Timer broadcast interrupts"),
+ S(IPI_IRQ_WORK, "IRQ work interrupts"),
+ S(IPI_WAKEUP, "CPU wake-up interrupts"),
+};
+
+static void smp_cross_call(const struct cpumask *target, unsigned int ipinr)
+{
+ trace_ipi_raise(target, ipi_types[ipinr]);
+ __smp_cross_call(target, ipinr);
+}
+
+void show_ipi_list(struct seq_file *p, int prec)
+{
+ unsigned int cpu, i;
+
+ for (i = 0; i < NR_IPI; i++) {
+ seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i,
+ prec >= 4 ? " " : "");
+ for_each_online_cpu(cpu)
+ seq_printf(p, "%10u ",
+ __get_irq_stat(cpu, ipi_irqs[i]));
+ seq_printf(p, " %s\n", ipi_types[i]);
+ }
+}
+
+u64 smp_irq_stat_cpu(unsigned int cpu)
+{
+ u64 sum = 0;
+ int i;
+
+ for (i = 0; i < NR_IPI; i++)
+ sum += __get_irq_stat(cpu, ipi_irqs[i]);
+
+ return sum;
+}
+
+void arch_send_call_function_ipi_mask(const struct cpumask *mask)
+{
+ smp_cross_call(mask, IPI_CALL_FUNC);
+}
+
+void arch_send_call_function_single_ipi(int cpu)
+{
+ smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC);
+}
+
+#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
+void arch_send_wakeup_ipi_mask(const struct cpumask *mask)
+{
+ smp_cross_call(mask, IPI_WAKEUP);
+}
+#endif
+
+#ifdef CONFIG_IRQ_WORK
+void arch_irq_work_raise(void)
+{
+ if (__smp_cross_call)
+ smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK);
+}
+#endif
+
+/*
+ * ipi_cpu_stop - handle IPI from smp_send_stop()
+ */
+static void ipi_cpu_stop(unsigned int cpu)
+{
+ set_cpu_online(cpu, false);
+
+ local_daif_mask();
+ sdei_mask_local_cpu();
+
+ while (1)
+ cpu_relax();
+}
+
+#ifdef CONFIG_KEXEC_CORE
+static atomic_t waiting_for_crash_ipi = ATOMIC_INIT(0);
+#endif
+
+static void ipi_cpu_crash_stop(unsigned int cpu, struct pt_regs *regs)
+{
+#ifdef CONFIG_KEXEC_CORE
+ crash_save_cpu(regs, cpu);
+
+ atomic_dec(&waiting_for_crash_ipi);
+
+ local_irq_disable();
+ sdei_mask_local_cpu();
+
+#ifdef CONFIG_HOTPLUG_CPU
+ if (cpu_ops[cpu]->cpu_die)
+ cpu_ops[cpu]->cpu_die(cpu);
+#endif
+
+ /* just in case */
+ cpu_park_loop();
+#endif
+}
+
+/*
+ * Main handler for inter-processor interrupts
+ */
+void handle_IPI(int ipinr, struct pt_regs *regs)
+{
+ unsigned int cpu = smp_processor_id();
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ if ((unsigned)ipinr < NR_IPI) {
+ trace_ipi_entry_rcuidle(ipi_types[ipinr]);
+ __inc_irq_stat(cpu, ipi_irqs[ipinr]);
+ }
+
+ switch (ipinr) {
+ case IPI_RESCHEDULE:
+ scheduler_ipi();
+ break;
+
+ case IPI_CALL_FUNC:
+ irq_enter();
+ generic_smp_call_function_interrupt();
+ irq_exit();
+ break;
+
+ case IPI_CPU_STOP:
+ irq_enter();
+ ipi_cpu_stop(cpu);
+ irq_exit();
+ break;
+
+ case IPI_CPU_CRASH_STOP:
+ if (IS_ENABLED(CONFIG_KEXEC_CORE)) {
+ irq_enter();
+ ipi_cpu_crash_stop(cpu, regs);
+
+ unreachable();
+ }
+ break;
+
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+ case IPI_TIMER:
+ irq_enter();
+ tick_receive_broadcast();
+ irq_exit();
+ break;
+#endif
+
+#ifdef CONFIG_IRQ_WORK
+ case IPI_IRQ_WORK:
+ irq_enter();
+ irq_work_run();
+ irq_exit();
+ break;
+#endif
+
+#ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL
+ case IPI_WAKEUP:
+ WARN_ONCE(!acpi_parking_protocol_valid(cpu),
+ "CPU%u: Wake-up IPI outside the ACPI parking protocol\n",
+ cpu);
+ break;
+#endif
+
+ default:
+ pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr);
+ break;
+ }
+
+ if ((unsigned)ipinr < NR_IPI)
+ trace_ipi_exit_rcuidle(ipi_types[ipinr]);
+ set_irq_regs(old_regs);
+}
+
+void smp_send_reschedule(int cpu)
+{
+ smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE);
+}
+
+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+void tick_broadcast(const struct cpumask *mask)
+{
+ smp_cross_call(mask, IPI_TIMER);
+}
+#endif
+
+void smp_send_stop(void)
+{
+ unsigned long timeout;
+
+ if (num_online_cpus() > 1) {
+ cpumask_t mask;
+
+ cpumask_copy(&mask, cpu_online_mask);
+ cpumask_clear_cpu(smp_processor_id(), &mask);
+
+ if (system_state <= SYSTEM_RUNNING)
+ pr_crit("SMP: stopping secondary CPUs\n");
+ smp_cross_call(&mask, IPI_CPU_STOP);
+ }
+
+ /* Wait up to one second for other CPUs to stop */
+ timeout = USEC_PER_SEC;
+ while (num_online_cpus() > 1 && timeout--)
+ udelay(1);
+
+ if (num_online_cpus() > 1)
+ pr_warning("SMP: failed to stop secondary CPUs %*pbl\n",
+ cpumask_pr_args(cpu_online_mask));
+
+ sdei_mask_local_cpu();
+}
+
+#ifdef CONFIG_KEXEC_CORE
+void crash_smp_send_stop(void)
+{
+ static int cpus_stopped;
+ cpumask_t mask;
+ unsigned long timeout;
+
+ /*
+ * This function can be called twice in panic path, but obviously
+ * we execute this only once.
+ */
+ if (cpus_stopped)
+ return;
+
+ cpus_stopped = 1;
+
+ if (num_online_cpus() == 1) {
+ sdei_mask_local_cpu();
+ return;
+ }
+
+ cpumask_copy(&mask, cpu_online_mask);
+ cpumask_clear_cpu(smp_processor_id(), &mask);
+
+ atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
+
+ pr_crit("SMP: stopping secondary CPUs\n");
+ smp_cross_call(&mask, IPI_CPU_CRASH_STOP);
+
+ /* Wait up to one second for other CPUs to stop */
+ timeout = USEC_PER_SEC;
+ while ((atomic_read(&waiting_for_crash_ipi) > 0) && timeout--)
+ udelay(1);
+
+ if (atomic_read(&waiting_for_crash_ipi) > 0)
+ pr_warning("SMP: failed to stop secondary CPUs %*pbl\n",
+ cpumask_pr_args(&mask));
+
+ sdei_mask_local_cpu();
+}
+
+bool smp_crash_stop_failed(void)
+{
+ return (atomic_read(&waiting_for_crash_ipi) > 0);
+}
+#endif
+
+/*
+ * not supported here
+ */
+int setup_profiling_timer(unsigned int multiplier)
+{
+ return -EINVAL;
+}
+
+static bool have_cpu_die(void)
+{
+#ifdef CONFIG_HOTPLUG_CPU
+ int any_cpu = raw_smp_processor_id();
+
+ if (cpu_ops[any_cpu] && cpu_ops[any_cpu]->cpu_die)
+ return true;
+#endif
+ return false;
+}
+
+bool cpus_are_stuck_in_kernel(void)
+{
+ bool smp_spin_tables = (num_possible_cpus() > 1 && !have_cpu_die());
+
+ return !!cpus_stuck_in_kernel || smp_spin_tables;
+}