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-rw-r--r--arch/x86/kernel/irq.c399
1 files changed, 399 insertions, 0 deletions
diff --git a/arch/x86/kernel/irq.c b/arch/x86/kernel/irq.c
new file mode 100644
index 000000000..766ffe3ba
--- /dev/null
+++ b/arch/x86/kernel/irq.c
@@ -0,0 +1,399 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Common interrupt code for 32 and 64 bit
+ */
+#include <linux/cpu.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+#include <linux/of.h>
+#include <linux/seq_file.h>
+#include <linux/smp.h>
+#include <linux/ftrace.h>
+#include <linux/delay.h>
+#include <linux/export.h>
+#include <linux/irq.h>
+
+#include <asm/irq_stack.h>
+#include <asm/apic.h>
+#include <asm/io_apic.h>
+#include <asm/irq.h>
+#include <asm/mce.h>
+#include <asm/hw_irq.h>
+#include <asm/desc.h>
+#include <asm/traps.h>
+#include <asm/thermal.h>
+
+#define CREATE_TRACE_POINTS
+#include <asm/trace/irq_vectors.h>
+
+DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
+EXPORT_PER_CPU_SYMBOL(irq_stat);
+
+atomic_t irq_err_count;
+
+/*
+ * 'what should we do if we get a hw irq event on an illegal vector'.
+ * each architecture has to answer this themselves.
+ */
+void ack_bad_irq(unsigned int irq)
+{
+ if (printk_ratelimit())
+ pr_err("unexpected IRQ trap at vector %02x\n", irq);
+
+ /*
+ * Currently unexpected vectors happen only on SMP and APIC.
+ * We _must_ ack these because every local APIC has only N
+ * irq slots per priority level, and a 'hanging, unacked' IRQ
+ * holds up an irq slot - in excessive cases (when multiple
+ * unexpected vectors occur) that might lock up the APIC
+ * completely.
+ * But only ack when the APIC is enabled -AK
+ */
+ ack_APIC_irq();
+}
+
+#define irq_stats(x) (&per_cpu(irq_stat, x))
+/*
+ * /proc/interrupts printing for arch specific interrupts
+ */
+int arch_show_interrupts(struct seq_file *p, int prec)
+{
+ int j;
+
+ seq_printf(p, "%*s: ", prec, "NMI");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->__nmi_count);
+ seq_puts(p, " Non-maskable interrupts\n");
+#ifdef CONFIG_X86_LOCAL_APIC
+ seq_printf(p, "%*s: ", prec, "LOC");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
+ seq_puts(p, " Local timer interrupts\n");
+
+ seq_printf(p, "%*s: ", prec, "SPU");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
+ seq_puts(p, " Spurious interrupts\n");
+ seq_printf(p, "%*s: ", prec, "PMI");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->apic_perf_irqs);
+ seq_puts(p, " Performance monitoring interrupts\n");
+ seq_printf(p, "%*s: ", prec, "IWI");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->apic_irq_work_irqs);
+ seq_puts(p, " IRQ work interrupts\n");
+ seq_printf(p, "%*s: ", prec, "RTR");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->icr_read_retry_count);
+ seq_puts(p, " APIC ICR read retries\n");
+ if (x86_platform_ipi_callback) {
+ seq_printf(p, "%*s: ", prec, "PLT");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->x86_platform_ipis);
+ seq_puts(p, " Platform interrupts\n");
+ }
+#endif
+#ifdef CONFIG_SMP
+ seq_printf(p, "%*s: ", prec, "RES");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
+ seq_puts(p, " Rescheduling interrupts\n");
+ seq_printf(p, "%*s: ", prec, "CAL");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
+ seq_puts(p, " Function call interrupts\n");
+ seq_printf(p, "%*s: ", prec, "TLB");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
+ seq_puts(p, " TLB shootdowns\n");
+#endif
+#ifdef CONFIG_X86_THERMAL_VECTOR
+ seq_printf(p, "%*s: ", prec, "TRM");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
+ seq_puts(p, " Thermal event interrupts\n");
+#endif
+#ifdef CONFIG_X86_MCE_THRESHOLD
+ seq_printf(p, "%*s: ", prec, "THR");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
+ seq_puts(p, " Threshold APIC interrupts\n");
+#endif
+#ifdef CONFIG_X86_MCE_AMD
+ seq_printf(p, "%*s: ", prec, "DFR");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->irq_deferred_error_count);
+ seq_puts(p, " Deferred Error APIC interrupts\n");
+#endif
+#ifdef CONFIG_X86_MCE
+ seq_printf(p, "%*s: ", prec, "MCE");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", per_cpu(mce_exception_count, j));
+ seq_puts(p, " Machine check exceptions\n");
+ seq_printf(p, "%*s: ", prec, "MCP");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
+ seq_puts(p, " Machine check polls\n");
+#endif
+#ifdef CONFIG_X86_HV_CALLBACK_VECTOR
+ if (test_bit(HYPERVISOR_CALLBACK_VECTOR, system_vectors)) {
+ seq_printf(p, "%*s: ", prec, "HYP");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ",
+ irq_stats(j)->irq_hv_callback_count);
+ seq_puts(p, " Hypervisor callback interrupts\n");
+ }
+#endif
+#if IS_ENABLED(CONFIG_HYPERV)
+ if (test_bit(HYPERV_REENLIGHTENMENT_VECTOR, system_vectors)) {
+ seq_printf(p, "%*s: ", prec, "HRE");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ",
+ irq_stats(j)->irq_hv_reenlightenment_count);
+ seq_puts(p, " Hyper-V reenlightenment interrupts\n");
+ }
+ if (test_bit(HYPERV_STIMER0_VECTOR, system_vectors)) {
+ seq_printf(p, "%*s: ", prec, "HVS");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ",
+ irq_stats(j)->hyperv_stimer0_count);
+ seq_puts(p, " Hyper-V stimer0 interrupts\n");
+ }
+#endif
+ seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
+#if defined(CONFIG_X86_IO_APIC)
+ seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
+#endif
+#ifdef CONFIG_HAVE_KVM
+ seq_printf(p, "%*s: ", prec, "PIN");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stats(j)->kvm_posted_intr_ipis);
+ seq_puts(p, " Posted-interrupt notification event\n");
+
+ seq_printf(p, "%*s: ", prec, "NPI");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ",
+ irq_stats(j)->kvm_posted_intr_nested_ipis);
+ seq_puts(p, " Nested posted-interrupt event\n");
+
+ seq_printf(p, "%*s: ", prec, "PIW");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ",
+ irq_stats(j)->kvm_posted_intr_wakeup_ipis);
+ seq_puts(p, " Posted-interrupt wakeup event\n");
+#endif
+ return 0;
+}
+
+/*
+ * /proc/stat helpers
+ */
+u64 arch_irq_stat_cpu(unsigned int cpu)
+{
+ u64 sum = irq_stats(cpu)->__nmi_count;
+
+#ifdef CONFIG_X86_LOCAL_APIC
+ sum += irq_stats(cpu)->apic_timer_irqs;
+ sum += irq_stats(cpu)->irq_spurious_count;
+ sum += irq_stats(cpu)->apic_perf_irqs;
+ sum += irq_stats(cpu)->apic_irq_work_irqs;
+ sum += irq_stats(cpu)->icr_read_retry_count;
+ if (x86_platform_ipi_callback)
+ sum += irq_stats(cpu)->x86_platform_ipis;
+#endif
+#ifdef CONFIG_SMP
+ sum += irq_stats(cpu)->irq_resched_count;
+ sum += irq_stats(cpu)->irq_call_count;
+#endif
+#ifdef CONFIG_X86_THERMAL_VECTOR
+ sum += irq_stats(cpu)->irq_thermal_count;
+#endif
+#ifdef CONFIG_X86_MCE_THRESHOLD
+ sum += irq_stats(cpu)->irq_threshold_count;
+#endif
+#ifdef CONFIG_X86_MCE
+ sum += per_cpu(mce_exception_count, cpu);
+ sum += per_cpu(mce_poll_count, cpu);
+#endif
+ return sum;
+}
+
+u64 arch_irq_stat(void)
+{
+ u64 sum = atomic_read(&irq_err_count);
+ return sum;
+}
+
+static __always_inline void handle_irq(struct irq_desc *desc,
+ struct pt_regs *regs)
+{
+ if (IS_ENABLED(CONFIG_X86_64))
+ generic_handle_irq_desc(desc);
+ else
+ __handle_irq(desc, regs);
+}
+
+/*
+ * common_interrupt() handles all normal device IRQ's (the special SMP
+ * cross-CPU interrupts have their own entry points).
+ */
+DEFINE_IDTENTRY_IRQ(common_interrupt)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+ struct irq_desc *desc;
+
+ /* entry code tells RCU that we're not quiescent. Check it. */
+ RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
+
+ desc = __this_cpu_read(vector_irq[vector]);
+ if (likely(!IS_ERR_OR_NULL(desc))) {
+ handle_irq(desc, regs);
+ } else {
+ ack_APIC_irq();
+
+ if (desc == VECTOR_UNUSED) {
+ pr_emerg_ratelimited("%s: %d.%u No irq handler for vector\n",
+ __func__, smp_processor_id(),
+ vector);
+ } else {
+ __this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
+ }
+ }
+
+ set_irq_regs(old_regs);
+}
+
+#ifdef CONFIG_X86_LOCAL_APIC
+/* Function pointer for generic interrupt vector handling */
+void (*x86_platform_ipi_callback)(void) = NULL;
+/*
+ * Handler for X86_PLATFORM_IPI_VECTOR.
+ */
+DEFINE_IDTENTRY_SYSVEC(sysvec_x86_platform_ipi)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+
+ ack_APIC_irq();
+ trace_x86_platform_ipi_entry(X86_PLATFORM_IPI_VECTOR);
+ inc_irq_stat(x86_platform_ipis);
+ if (x86_platform_ipi_callback)
+ x86_platform_ipi_callback();
+ trace_x86_platform_ipi_exit(X86_PLATFORM_IPI_VECTOR);
+ set_irq_regs(old_regs);
+}
+#endif
+
+#ifdef CONFIG_HAVE_KVM
+static void dummy_handler(void) {}
+static void (*kvm_posted_intr_wakeup_handler)(void) = dummy_handler;
+
+void kvm_set_posted_intr_wakeup_handler(void (*handler)(void))
+{
+ if (handler)
+ kvm_posted_intr_wakeup_handler = handler;
+ else {
+ kvm_posted_intr_wakeup_handler = dummy_handler;
+ synchronize_rcu();
+ }
+}
+EXPORT_SYMBOL_GPL(kvm_set_posted_intr_wakeup_handler);
+
+/*
+ * Handler for POSTED_INTERRUPT_VECTOR.
+ */
+DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_kvm_posted_intr_ipi)
+{
+ ack_APIC_irq();
+ inc_irq_stat(kvm_posted_intr_ipis);
+}
+
+/*
+ * Handler for POSTED_INTERRUPT_WAKEUP_VECTOR.
+ */
+DEFINE_IDTENTRY_SYSVEC(sysvec_kvm_posted_intr_wakeup_ipi)
+{
+ ack_APIC_irq();
+ inc_irq_stat(kvm_posted_intr_wakeup_ipis);
+ kvm_posted_intr_wakeup_handler();
+}
+
+/*
+ * Handler for POSTED_INTERRUPT_NESTED_VECTOR.
+ */
+DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_kvm_posted_intr_nested_ipi)
+{
+ ack_APIC_irq();
+ inc_irq_stat(kvm_posted_intr_nested_ipis);
+}
+#endif
+
+
+#ifdef CONFIG_HOTPLUG_CPU
+/* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
+void fixup_irqs(void)
+{
+ unsigned int irr, vector;
+ struct irq_desc *desc;
+ struct irq_data *data;
+ struct irq_chip *chip;
+
+ irq_migrate_all_off_this_cpu();
+
+ /*
+ * We can remove mdelay() and then send spurious interrupts to
+ * new cpu targets for all the irqs that were handled previously by
+ * this cpu. While it works, I have seen spurious interrupt messages
+ * (nothing wrong but still...).
+ *
+ * So for now, retain mdelay(1) and check the IRR and then send those
+ * interrupts to new targets as this cpu is already offlined...
+ */
+ mdelay(1);
+
+ /*
+ * We can walk the vector array of this cpu without holding
+ * vector_lock because the cpu is already marked !online, so
+ * nothing else will touch it.
+ */
+ for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
+ if (IS_ERR_OR_NULL(__this_cpu_read(vector_irq[vector])))
+ continue;
+
+ irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
+ if (irr & (1 << (vector % 32))) {
+ desc = __this_cpu_read(vector_irq[vector]);
+
+ raw_spin_lock(&desc->lock);
+ data = irq_desc_get_irq_data(desc);
+ chip = irq_data_get_irq_chip(data);
+ if (chip->irq_retrigger) {
+ chip->irq_retrigger(data);
+ __this_cpu_write(vector_irq[vector], VECTOR_RETRIGGERED);
+ }
+ raw_spin_unlock(&desc->lock);
+ }
+ if (__this_cpu_read(vector_irq[vector]) != VECTOR_RETRIGGERED)
+ __this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
+ }
+}
+#endif
+
+#ifdef CONFIG_X86_THERMAL_VECTOR
+static void smp_thermal_vector(void)
+{
+ if (x86_thermal_enabled())
+ intel_thermal_interrupt();
+ else
+ pr_err("CPU%d: Unexpected LVT thermal interrupt!\n",
+ smp_processor_id());
+}
+
+DEFINE_IDTENTRY_SYSVEC(sysvec_thermal)
+{
+ trace_thermal_apic_entry(THERMAL_APIC_VECTOR);
+ inc_irq_stat(irq_thermal_count);
+ smp_thermal_vector();
+ trace_thermal_apic_exit(THERMAL_APIC_VECTOR);
+ ack_APIC_irq();
+}
+#endif