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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Common interrupt code for 32 and 64 bit
  4 */
  5#include <linux/cpu.h>
  6#include <linux/interrupt.h>
  7#include <linux/kernel_stat.h>
  8#include <linux/of.h>
  9#include <linux/seq_file.h>
 10#include <linux/smp.h>
 11#include <linux/ftrace.h>
 12#include <linux/delay.h>
 13#include <linux/export.h>
 14#include <linux/irq.h>
 15
 16#include <asm/irq_stack.h>
 17#include <asm/apic.h>
 18#include <asm/io_apic.h>
 19#include <asm/irq.h>
 20#include <asm/mce.h>
 21#include <asm/hw_irq.h>
 22#include <asm/desc.h>
 23#include <asm/traps.h>
 24#include <asm/thermal.h>
 25#include <asm/posted_intr.h>
 26#include <asm/irq_remapping.h>
 27
 28#define CREATE_TRACE_POINTS
 29#include <asm/trace/irq_vectors.h>
 30
 31DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
 32EXPORT_PER_CPU_SYMBOL(irq_stat);
 33
 
 
 
 34atomic_t irq_err_count;
 35
 36/*
 37 * 'what should we do if we get a hw irq event on an illegal vector'.
 38 * each architecture has to answer this themselves.
 39 */
 40void ack_bad_irq(unsigned int irq)
 41{
 42	if (printk_ratelimit())
 43		pr_err("unexpected IRQ trap at vector %02x\n", irq);
 44
 45	/*
 46	 * Currently unexpected vectors happen only on SMP and APIC.
 47	 * We _must_ ack these because every local APIC has only N
 48	 * irq slots per priority level, and a 'hanging, unacked' IRQ
 49	 * holds up an irq slot - in excessive cases (when multiple
 50	 * unexpected vectors occur) that might lock up the APIC
 51	 * completely.
 52	 * But only ack when the APIC is enabled -AK
 53	 */
 54	apic_eoi();
 55}
 56
 57#define irq_stats(x)		(&per_cpu(irq_stat, x))
 58/*
 59 * /proc/interrupts printing for arch specific interrupts
 60 */
 61int arch_show_interrupts(struct seq_file *p, int prec)
 62{
 63	int j;
 64
 65	seq_printf(p, "%*s: ", prec, "NMI");
 66	for_each_online_cpu(j)
 67		seq_printf(p, "%10u ", irq_stats(j)->__nmi_count);
 68	seq_puts(p, "  Non-maskable interrupts\n");
 69#ifdef CONFIG_X86_LOCAL_APIC
 70	seq_printf(p, "%*s: ", prec, "LOC");
 71	for_each_online_cpu(j)
 72		seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
 73	seq_puts(p, "  Local timer interrupts\n");
 74
 75	seq_printf(p, "%*s: ", prec, "SPU");
 76	for_each_online_cpu(j)
 77		seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
 78	seq_puts(p, "  Spurious interrupts\n");
 79	seq_printf(p, "%*s: ", prec, "PMI");
 80	for_each_online_cpu(j)
 81		seq_printf(p, "%10u ", irq_stats(j)->apic_perf_irqs);
 82	seq_puts(p, "  Performance monitoring interrupts\n");
 83	seq_printf(p, "%*s: ", prec, "IWI");
 84	for_each_online_cpu(j)
 85		seq_printf(p, "%10u ", irq_stats(j)->apic_irq_work_irqs);
 86	seq_puts(p, "  IRQ work interrupts\n");
 87	seq_printf(p, "%*s: ", prec, "RTR");
 88	for_each_online_cpu(j)
 89		seq_printf(p, "%10u ", irq_stats(j)->icr_read_retry_count);
 90	seq_puts(p, "  APIC ICR read retries\n");
 91	if (x86_platform_ipi_callback) {
 92		seq_printf(p, "%*s: ", prec, "PLT");
 93		for_each_online_cpu(j)
 94			seq_printf(p, "%10u ", irq_stats(j)->x86_platform_ipis);
 95		seq_puts(p, "  Platform interrupts\n");
 96	}
 97#endif
 98#ifdef CONFIG_SMP
 99	seq_printf(p, "%*s: ", prec, "RES");
100	for_each_online_cpu(j)
101		seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
102	seq_puts(p, "  Rescheduling interrupts\n");
103	seq_printf(p, "%*s: ", prec, "CAL");
104	for_each_online_cpu(j)
105		seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
106	seq_puts(p, "  Function call interrupts\n");
107	seq_printf(p, "%*s: ", prec, "TLB");
108	for_each_online_cpu(j)
109		seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
110	seq_puts(p, "  TLB shootdowns\n");
111#endif
112#ifdef CONFIG_X86_THERMAL_VECTOR
113	seq_printf(p, "%*s: ", prec, "TRM");
114	for_each_online_cpu(j)
115		seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
116	seq_puts(p, "  Thermal event interrupts\n");
117#endif
118#ifdef CONFIG_X86_MCE_THRESHOLD
119	seq_printf(p, "%*s: ", prec, "THR");
120	for_each_online_cpu(j)
121		seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
122	seq_puts(p, "  Threshold APIC interrupts\n");
123#endif
124#ifdef CONFIG_X86_MCE_AMD
125	seq_printf(p, "%*s: ", prec, "DFR");
126	for_each_online_cpu(j)
127		seq_printf(p, "%10u ", irq_stats(j)->irq_deferred_error_count);
128	seq_puts(p, "  Deferred Error APIC interrupts\n");
129#endif
130#ifdef CONFIG_X86_MCE
131	seq_printf(p, "%*s: ", prec, "MCE");
132	for_each_online_cpu(j)
133		seq_printf(p, "%10u ", per_cpu(mce_exception_count, j));
134	seq_puts(p, "  Machine check exceptions\n");
135	seq_printf(p, "%*s: ", prec, "MCP");
136	for_each_online_cpu(j)
137		seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
138	seq_puts(p, "  Machine check polls\n");
139#endif
140#ifdef CONFIG_X86_HV_CALLBACK_VECTOR
141	if (test_bit(HYPERVISOR_CALLBACK_VECTOR, system_vectors)) {
142		seq_printf(p, "%*s: ", prec, "HYP");
143		for_each_online_cpu(j)
144			seq_printf(p, "%10u ",
145				   irq_stats(j)->irq_hv_callback_count);
146		seq_puts(p, "  Hypervisor callback interrupts\n");
147	}
148#endif
149#if IS_ENABLED(CONFIG_HYPERV)
150	if (test_bit(HYPERV_REENLIGHTENMENT_VECTOR, system_vectors)) {
151		seq_printf(p, "%*s: ", prec, "HRE");
152		for_each_online_cpu(j)
153			seq_printf(p, "%10u ",
154				   irq_stats(j)->irq_hv_reenlightenment_count);
155		seq_puts(p, "  Hyper-V reenlightenment interrupts\n");
156	}
157	if (test_bit(HYPERV_STIMER0_VECTOR, system_vectors)) {
158		seq_printf(p, "%*s: ", prec, "HVS");
159		for_each_online_cpu(j)
160			seq_printf(p, "%10u ",
161				   irq_stats(j)->hyperv_stimer0_count);
162		seq_puts(p, "  Hyper-V stimer0 interrupts\n");
163	}
164#endif
165	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
166#if defined(CONFIG_X86_IO_APIC)
167	seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
168#endif
169#if IS_ENABLED(CONFIG_KVM)
170	seq_printf(p, "%*s: ", prec, "PIN");
171	for_each_online_cpu(j)
172		seq_printf(p, "%10u ", irq_stats(j)->kvm_posted_intr_ipis);
173	seq_puts(p, "  Posted-interrupt notification event\n");
174
175	seq_printf(p, "%*s: ", prec, "NPI");
176	for_each_online_cpu(j)
177		seq_printf(p, "%10u ",
178			   irq_stats(j)->kvm_posted_intr_nested_ipis);
179	seq_puts(p, "  Nested posted-interrupt event\n");
180
181	seq_printf(p, "%*s: ", prec, "PIW");
182	for_each_online_cpu(j)
183		seq_printf(p, "%10u ",
184			   irq_stats(j)->kvm_posted_intr_wakeup_ipis);
185	seq_puts(p, "  Posted-interrupt wakeup event\n");
186#endif
187#ifdef CONFIG_X86_POSTED_MSI
188	seq_printf(p, "%*s: ", prec, "PMN");
189	for_each_online_cpu(j)
190		seq_printf(p, "%10u ",
191			   irq_stats(j)->posted_msi_notification_count);
192	seq_puts(p, "  Posted MSI notification event\n");
193#endif
194	return 0;
195}
196
197/*
198 * /proc/stat helpers
199 */
200u64 arch_irq_stat_cpu(unsigned int cpu)
201{
202	u64 sum = irq_stats(cpu)->__nmi_count;
203
204#ifdef CONFIG_X86_LOCAL_APIC
205	sum += irq_stats(cpu)->apic_timer_irqs;
206	sum += irq_stats(cpu)->irq_spurious_count;
207	sum += irq_stats(cpu)->apic_perf_irqs;
208	sum += irq_stats(cpu)->apic_irq_work_irqs;
209	sum += irq_stats(cpu)->icr_read_retry_count;
210	if (x86_platform_ipi_callback)
211		sum += irq_stats(cpu)->x86_platform_ipis;
212#endif
213#ifdef CONFIG_SMP
214	sum += irq_stats(cpu)->irq_resched_count;
215	sum += irq_stats(cpu)->irq_call_count;
216#endif
217#ifdef CONFIG_X86_THERMAL_VECTOR
218	sum += irq_stats(cpu)->irq_thermal_count;
219#endif
220#ifdef CONFIG_X86_MCE_THRESHOLD
221	sum += irq_stats(cpu)->irq_threshold_count;
222#endif
223#ifdef CONFIG_X86_HV_CALLBACK_VECTOR
224	sum += irq_stats(cpu)->irq_hv_callback_count;
225#endif
226#if IS_ENABLED(CONFIG_HYPERV)
227	sum += irq_stats(cpu)->irq_hv_reenlightenment_count;
228	sum += irq_stats(cpu)->hyperv_stimer0_count;
229#endif
230#ifdef CONFIG_X86_MCE
231	sum += per_cpu(mce_exception_count, cpu);
232	sum += per_cpu(mce_poll_count, cpu);
233#endif
234	return sum;
235}
236
237u64 arch_irq_stat(void)
238{
239	u64 sum = atomic_read(&irq_err_count);
240	return sum;
241}
242
243static __always_inline void handle_irq(struct irq_desc *desc,
244				       struct pt_regs *regs)
245{
246	if (IS_ENABLED(CONFIG_X86_64))
247		generic_handle_irq_desc(desc);
248	else
249		__handle_irq(desc, regs);
250}
251
252static __always_inline int call_irq_handler(int vector, struct pt_regs *regs)
 
 
 
 
 
253{
254	struct irq_desc *desc;
255	int ret = 0;
 
 
 
 
 
 
 
256
257	desc = __this_cpu_read(vector_irq[vector]);
258	if (likely(!IS_ERR_OR_NULL(desc))) {
259		handle_irq(desc, regs);
260	} else {
261		ret = -EINVAL;
262		if (desc == VECTOR_UNUSED) {
263			pr_emerg_ratelimited("%s: %d.%u No irq handler for vector\n",
264					     __func__, smp_processor_id(),
265					     vector);
266		} else {
267			__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
268		}
269	}
270
271	return ret;
272}
273
274/*
275 * common_interrupt() handles all normal device IRQ's (the special SMP
276 * cross-CPU interrupts have their own entry points).
277 */
278DEFINE_IDTENTRY_IRQ(common_interrupt)
279{
280	struct pt_regs *old_regs = set_irq_regs(regs);
281
282	/* entry code tells RCU that we're not quiescent.  Check it. */
283	RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
284
285	if (unlikely(call_irq_handler(vector, regs)))
286		apic_eoi();
287
288	set_irq_regs(old_regs);
 
289}
290
291#ifdef CONFIG_X86_LOCAL_APIC
292/* Function pointer for generic interrupt vector handling */
293void (*x86_platform_ipi_callback)(void) = NULL;
294/*
295 * Handler for X86_PLATFORM_IPI_VECTOR.
296 */
297DEFINE_IDTENTRY_SYSVEC(sysvec_x86_platform_ipi)
298{
299	struct pt_regs *old_regs = set_irq_regs(regs);
300
301	apic_eoi();
302	trace_x86_platform_ipi_entry(X86_PLATFORM_IPI_VECTOR);
303	inc_irq_stat(x86_platform_ipis);
304	if (x86_platform_ipi_callback)
305		x86_platform_ipi_callback();
306	trace_x86_platform_ipi_exit(X86_PLATFORM_IPI_VECTOR);
 
307	set_irq_regs(old_regs);
308}
309#endif
310
311#if IS_ENABLED(CONFIG_KVM)
312static void dummy_handler(void) {}
313static void (*kvm_posted_intr_wakeup_handler)(void) = dummy_handler;
314
315void kvm_set_posted_intr_wakeup_handler(void (*handler)(void))
316{
317	if (handler)
318		kvm_posted_intr_wakeup_handler = handler;
319	else {
320		kvm_posted_intr_wakeup_handler = dummy_handler;
321		synchronize_rcu();
322	}
323}
324EXPORT_SYMBOL_GPL(kvm_set_posted_intr_wakeup_handler);
325
326/*
327 * Handler for POSTED_INTERRUPT_VECTOR.
328 */
329DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_kvm_posted_intr_ipi)
330{
331	apic_eoi();
 
 
332	inc_irq_stat(kvm_posted_intr_ipis);
 
 
333}
334
335/*
336 * Handler for POSTED_INTERRUPT_WAKEUP_VECTOR.
337 */
338DEFINE_IDTENTRY_SYSVEC(sysvec_kvm_posted_intr_wakeup_ipi)
339{
340	apic_eoi();
 
 
341	inc_irq_stat(kvm_posted_intr_wakeup_ipis);
342	kvm_posted_intr_wakeup_handler();
 
 
343}
344
345/*
346 * Handler for POSTED_INTERRUPT_NESTED_VECTOR.
347 */
348DEFINE_IDTENTRY_SYSVEC_SIMPLE(sysvec_kvm_posted_intr_nested_ipi)
349{
350	apic_eoi();
351	inc_irq_stat(kvm_posted_intr_nested_ipis);
352}
353#endif
354
355#ifdef CONFIG_X86_POSTED_MSI
356
357/* Posted Interrupt Descriptors for coalesced MSIs to be posted */
358DEFINE_PER_CPU_ALIGNED(struct pi_desc, posted_msi_pi_desc);
359
360void intel_posted_msi_init(void)
361{
362	u32 destination;
363	u32 apic_id;
364
365	this_cpu_write(posted_msi_pi_desc.nv, POSTED_MSI_NOTIFICATION_VECTOR);
366
367	/*
368	 * APIC destination ID is stored in bit 8:15 while in XAPIC mode.
369	 * VT-d spec. CH 9.11
370	 */
371	apic_id = this_cpu_read(x86_cpu_to_apicid);
372	destination = x2apic_enabled() ? apic_id : apic_id << 8;
373	this_cpu_write(posted_msi_pi_desc.ndst, destination);
374}
375
376/*
377 * De-multiplexing posted interrupts is on the performance path, the code
378 * below is written to optimize the cache performance based on the following
379 * considerations:
380 * 1.Posted interrupt descriptor (PID) fits in a cache line that is frequently
381 *   accessed by both CPU and IOMMU.
382 * 2.During posted MSI processing, the CPU needs to do 64-bit read and xchg
383 *   for checking and clearing posted interrupt request (PIR), a 256 bit field
384 *   within the PID.
385 * 3.On the other side, the IOMMU does atomic swaps of the entire PID cache
386 *   line when posting interrupts and setting control bits.
387 * 4.The CPU can access the cache line a magnitude faster than the IOMMU.
388 * 5.Each time the IOMMU does interrupt posting to the PIR will evict the PID
389 *   cache line. The cache line states after each operation are as follows:
390 *   CPU		IOMMU			PID Cache line state
391 *   ---------------------------------------------------------------
392 *...read64					exclusive
393 *...lock xchg64				modified
394 *...			post/atomic swap	invalid
395 *...-------------------------------------------------------------
396 *
397 * To reduce L1 data cache miss, it is important to avoid contention with
398 * IOMMU's interrupt posting/atomic swap. Therefore, a copy of PIR is used
399 * to dispatch interrupt handlers.
400 *
401 * In addition, the code is trying to keep the cache line state consistent
402 * as much as possible. e.g. when making a copy and clearing the PIR
403 * (assuming non-zero PIR bits are present in the entire PIR), it does:
404 *		read, read, read, read, xchg, xchg, xchg, xchg
405 * instead of:
406 *		read, xchg, read, xchg, read, xchg, read, xchg
407 */
408static __always_inline bool handle_pending_pir(u64 *pir, struct pt_regs *regs)
409{
410	int i, vec = FIRST_EXTERNAL_VECTOR;
411	unsigned long pir_copy[4];
412	bool handled = false;
413
414	for (i = 0; i < 4; i++)
415		pir_copy[i] = pir[i];
416
417	for (i = 0; i < 4; i++) {
418		if (!pir_copy[i])
419			continue;
420
421		pir_copy[i] = arch_xchg(&pir[i], 0);
422		handled = true;
423	}
424
425	if (handled) {
426		for_each_set_bit_from(vec, pir_copy, FIRST_SYSTEM_VECTOR)
427			call_irq_handler(vec, regs);
428	}
429
430	return handled;
431}
432
433/*
434 * Performance data shows that 3 is good enough to harvest 90+% of the benefit
435 * on high IRQ rate workload.
436 */
437#define MAX_POSTED_MSI_COALESCING_LOOP 3
438
439/*
440 * For MSIs that are delivered as posted interrupts, the CPU notifications
441 * can be coalesced if the MSIs arrive in high frequency bursts.
442 */
443DEFINE_IDTENTRY_SYSVEC(sysvec_posted_msi_notification)
444{
445	struct pt_regs *old_regs = set_irq_regs(regs);
446	struct pi_desc *pid;
447	int i = 0;
448
449	pid = this_cpu_ptr(&posted_msi_pi_desc);
450
451	inc_irq_stat(posted_msi_notification_count);
452	irq_enter();
453
454	/*
455	 * Max coalescing count includes the extra round of handle_pending_pir
456	 * after clearing the outstanding notification bit. Hence, at most
457	 * MAX_POSTED_MSI_COALESCING_LOOP - 1 loops are executed here.
458	 */
459	while (++i < MAX_POSTED_MSI_COALESCING_LOOP) {
460		if (!handle_pending_pir(pid->pir64, regs))
461			break;
462	}
463
464	/*
465	 * Clear outstanding notification bit to allow new IRQ notifications,
466	 * do this last to maximize the window of interrupt coalescing.
467	 */
468	pi_clear_on(pid);
469
470	/*
471	 * There could be a race of PI notification and the clearing of ON bit,
472	 * process PIR bits one last time such that handling the new interrupts
473	 * are not delayed until the next IRQ.
474	 */
475	handle_pending_pir(pid->pir64, regs);
476
477	apic_eoi();
478	irq_exit();
479	set_irq_regs(old_regs);
480}
481#endif /* X86_POSTED_MSI */
 
482
483#ifdef CONFIG_HOTPLUG_CPU
484/* A cpu has been removed from cpu_online_mask.  Reset irq affinities. */
485void fixup_irqs(void)
486{
487	unsigned int vector;
488	struct irq_desc *desc;
489	struct irq_data *data;
490	struct irq_chip *chip;
491
492	irq_migrate_all_off_this_cpu();
493
494	/*
495	 * We can remove mdelay() and then send spurious interrupts to
496	 * new cpu targets for all the irqs that were handled previously by
497	 * this cpu. While it works, I have seen spurious interrupt messages
498	 * (nothing wrong but still...).
499	 *
500	 * So for now, retain mdelay(1) and check the IRR and then send those
501	 * interrupts to new targets as this cpu is already offlined...
502	 */
503	mdelay(1);
504
505	/*
506	 * We can walk the vector array of this cpu without holding
507	 * vector_lock because the cpu is already marked !online, so
508	 * nothing else will touch it.
509	 */
510	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
511		if (IS_ERR_OR_NULL(__this_cpu_read(vector_irq[vector])))
512			continue;
513
514		if (is_vector_pending(vector)) {
 
515			desc = __this_cpu_read(vector_irq[vector]);
516
517			raw_spin_lock(&desc->lock);
518			data = irq_desc_get_irq_data(desc);
519			chip = irq_data_get_irq_chip(data);
520			if (chip->irq_retrigger) {
521				chip->irq_retrigger(data);
522				__this_cpu_write(vector_irq[vector], VECTOR_RETRIGGERED);
523			}
524			raw_spin_unlock(&desc->lock);
525		}
526		if (__this_cpu_read(vector_irq[vector]) != VECTOR_RETRIGGERED)
527			__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
528	}
529}
530#endif
531
532#ifdef CONFIG_X86_THERMAL_VECTOR
533static void smp_thermal_vector(void)
534{
535	if (x86_thermal_enabled())
536		intel_thermal_interrupt();
537	else
538		pr_err("CPU%d: Unexpected LVT thermal interrupt!\n",
539		       smp_processor_id());
540}
541
542DEFINE_IDTENTRY_SYSVEC(sysvec_thermal)
543{
544	trace_thermal_apic_entry(THERMAL_APIC_VECTOR);
545	inc_irq_stat(irq_thermal_count);
546	smp_thermal_vector();
547	trace_thermal_apic_exit(THERMAL_APIC_VECTOR);
548	apic_eoi();
549}
550#endif
v4.17
 
  1/*
  2 * Common interrupt code for 32 and 64 bit
  3 */
  4#include <linux/cpu.h>
  5#include <linux/interrupt.h>
  6#include <linux/kernel_stat.h>
  7#include <linux/of.h>
  8#include <linux/seq_file.h>
  9#include <linux/smp.h>
 10#include <linux/ftrace.h>
 11#include <linux/delay.h>
 12#include <linux/export.h>
 
 13
 
 14#include <asm/apic.h>
 15#include <asm/io_apic.h>
 16#include <asm/irq.h>
 17#include <asm/mce.h>
 18#include <asm/hw_irq.h>
 19#include <asm/desc.h>
 
 
 
 
 20
 21#define CREATE_TRACE_POINTS
 22#include <asm/trace/irq_vectors.h>
 23
 24DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
 25EXPORT_PER_CPU_SYMBOL(irq_stat);
 26
 27DEFINE_PER_CPU(struct pt_regs *, irq_regs);
 28EXPORT_PER_CPU_SYMBOL(irq_regs);
 29
 30atomic_t irq_err_count;
 31
 32/*
 33 * 'what should we do if we get a hw irq event on an illegal vector'.
 34 * each architecture has to answer this themselves.
 35 */
 36void ack_bad_irq(unsigned int irq)
 37{
 38	if (printk_ratelimit())
 39		pr_err("unexpected IRQ trap at vector %02x\n", irq);
 40
 41	/*
 42	 * Currently unexpected vectors happen only on SMP and APIC.
 43	 * We _must_ ack these because every local APIC has only N
 44	 * irq slots per priority level, and a 'hanging, unacked' IRQ
 45	 * holds up an irq slot - in excessive cases (when multiple
 46	 * unexpected vectors occur) that might lock up the APIC
 47	 * completely.
 48	 * But only ack when the APIC is enabled -AK
 49	 */
 50	ack_APIC_irq();
 51}
 52
 53#define irq_stats(x)		(&per_cpu(irq_stat, x))
 54/*
 55 * /proc/interrupts printing for arch specific interrupts
 56 */
 57int arch_show_interrupts(struct seq_file *p, int prec)
 58{
 59	int j;
 60
 61	seq_printf(p, "%*s: ", prec, "NMI");
 62	for_each_online_cpu(j)
 63		seq_printf(p, "%10u ", irq_stats(j)->__nmi_count);
 64	seq_puts(p, "  Non-maskable interrupts\n");
 65#ifdef CONFIG_X86_LOCAL_APIC
 66	seq_printf(p, "%*s: ", prec, "LOC");
 67	for_each_online_cpu(j)
 68		seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
 69	seq_puts(p, "  Local timer interrupts\n");
 70
 71	seq_printf(p, "%*s: ", prec, "SPU");
 72	for_each_online_cpu(j)
 73		seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
 74	seq_puts(p, "  Spurious interrupts\n");
 75	seq_printf(p, "%*s: ", prec, "PMI");
 76	for_each_online_cpu(j)
 77		seq_printf(p, "%10u ", irq_stats(j)->apic_perf_irqs);
 78	seq_puts(p, "  Performance monitoring interrupts\n");
 79	seq_printf(p, "%*s: ", prec, "IWI");
 80	for_each_online_cpu(j)
 81		seq_printf(p, "%10u ", irq_stats(j)->apic_irq_work_irqs);
 82	seq_puts(p, "  IRQ work interrupts\n");
 83	seq_printf(p, "%*s: ", prec, "RTR");
 84	for_each_online_cpu(j)
 85		seq_printf(p, "%10u ", irq_stats(j)->icr_read_retry_count);
 86	seq_puts(p, "  APIC ICR read retries\n");
 87	if (x86_platform_ipi_callback) {
 88		seq_printf(p, "%*s: ", prec, "PLT");
 89		for_each_online_cpu(j)
 90			seq_printf(p, "%10u ", irq_stats(j)->x86_platform_ipis);
 91		seq_puts(p, "  Platform interrupts\n");
 92	}
 93#endif
 94#ifdef CONFIG_SMP
 95	seq_printf(p, "%*s: ", prec, "RES");
 96	for_each_online_cpu(j)
 97		seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
 98	seq_puts(p, "  Rescheduling interrupts\n");
 99	seq_printf(p, "%*s: ", prec, "CAL");
100	for_each_online_cpu(j)
101		seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
102	seq_puts(p, "  Function call interrupts\n");
103	seq_printf(p, "%*s: ", prec, "TLB");
104	for_each_online_cpu(j)
105		seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
106	seq_puts(p, "  TLB shootdowns\n");
107#endif
108#ifdef CONFIG_X86_THERMAL_VECTOR
109	seq_printf(p, "%*s: ", prec, "TRM");
110	for_each_online_cpu(j)
111		seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
112	seq_puts(p, "  Thermal event interrupts\n");
113#endif
114#ifdef CONFIG_X86_MCE_THRESHOLD
115	seq_printf(p, "%*s: ", prec, "THR");
116	for_each_online_cpu(j)
117		seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
118	seq_puts(p, "  Threshold APIC interrupts\n");
119#endif
120#ifdef CONFIG_X86_MCE_AMD
121	seq_printf(p, "%*s: ", prec, "DFR");
122	for_each_online_cpu(j)
123		seq_printf(p, "%10u ", irq_stats(j)->irq_deferred_error_count);
124	seq_puts(p, "  Deferred Error APIC interrupts\n");
125#endif
126#ifdef CONFIG_X86_MCE
127	seq_printf(p, "%*s: ", prec, "MCE");
128	for_each_online_cpu(j)
129		seq_printf(p, "%10u ", per_cpu(mce_exception_count, j));
130	seq_puts(p, "  Machine check exceptions\n");
131	seq_printf(p, "%*s: ", prec, "MCP");
132	for_each_online_cpu(j)
133		seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
134	seq_puts(p, "  Machine check polls\n");
135#endif
136#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
137	if (test_bit(HYPERVISOR_CALLBACK_VECTOR, system_vectors)) {
138		seq_printf(p, "%*s: ", prec, "HYP");
139		for_each_online_cpu(j)
140			seq_printf(p, "%10u ",
141				   irq_stats(j)->irq_hv_callback_count);
142		seq_puts(p, "  Hypervisor callback interrupts\n");
143	}
144#endif
145#if IS_ENABLED(CONFIG_HYPERV)
146	if (test_bit(HYPERV_REENLIGHTENMENT_VECTOR, system_vectors)) {
147		seq_printf(p, "%*s: ", prec, "HRE");
148		for_each_online_cpu(j)
149			seq_printf(p, "%10u ",
150				   irq_stats(j)->irq_hv_reenlightenment_count);
151		seq_puts(p, "  Hyper-V reenlightenment interrupts\n");
152	}
153	if (test_bit(HYPERV_STIMER0_VECTOR, system_vectors)) {
154		seq_printf(p, "%*s: ", prec, "HVS");
155		for_each_online_cpu(j)
156			seq_printf(p, "%10u ",
157				   irq_stats(j)->hyperv_stimer0_count);
158		seq_puts(p, "  Hyper-V stimer0 interrupts\n");
159	}
160#endif
161	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
162#if defined(CONFIG_X86_IO_APIC)
163	seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
164#endif
165#ifdef CONFIG_HAVE_KVM
166	seq_printf(p, "%*s: ", prec, "PIN");
167	for_each_online_cpu(j)
168		seq_printf(p, "%10u ", irq_stats(j)->kvm_posted_intr_ipis);
169	seq_puts(p, "  Posted-interrupt notification event\n");
170
171	seq_printf(p, "%*s: ", prec, "NPI");
172	for_each_online_cpu(j)
173		seq_printf(p, "%10u ",
174			   irq_stats(j)->kvm_posted_intr_nested_ipis);
175	seq_puts(p, "  Nested posted-interrupt event\n");
176
177	seq_printf(p, "%*s: ", prec, "PIW");
178	for_each_online_cpu(j)
179		seq_printf(p, "%10u ",
180			   irq_stats(j)->kvm_posted_intr_wakeup_ipis);
181	seq_puts(p, "  Posted-interrupt wakeup event\n");
182#endif
 
 
 
 
 
 
 
183	return 0;
184}
185
186/*
187 * /proc/stat helpers
188 */
189u64 arch_irq_stat_cpu(unsigned int cpu)
190{
191	u64 sum = irq_stats(cpu)->__nmi_count;
192
193#ifdef CONFIG_X86_LOCAL_APIC
194	sum += irq_stats(cpu)->apic_timer_irqs;
195	sum += irq_stats(cpu)->irq_spurious_count;
196	sum += irq_stats(cpu)->apic_perf_irqs;
197	sum += irq_stats(cpu)->apic_irq_work_irqs;
198	sum += irq_stats(cpu)->icr_read_retry_count;
199	if (x86_platform_ipi_callback)
200		sum += irq_stats(cpu)->x86_platform_ipis;
201#endif
202#ifdef CONFIG_SMP
203	sum += irq_stats(cpu)->irq_resched_count;
204	sum += irq_stats(cpu)->irq_call_count;
205#endif
206#ifdef CONFIG_X86_THERMAL_VECTOR
207	sum += irq_stats(cpu)->irq_thermal_count;
208#endif
209#ifdef CONFIG_X86_MCE_THRESHOLD
210	sum += irq_stats(cpu)->irq_threshold_count;
211#endif
 
 
 
 
 
 
 
212#ifdef CONFIG_X86_MCE
213	sum += per_cpu(mce_exception_count, cpu);
214	sum += per_cpu(mce_poll_count, cpu);
215#endif
216	return sum;
217}
218
219u64 arch_irq_stat(void)
220{
221	u64 sum = atomic_read(&irq_err_count);
222	return sum;
223}
224
 
 
 
 
 
 
 
 
225
226/*
227 * do_IRQ handles all normal device IRQ's (the special
228 * SMP cross-CPU interrupts have their own specific
229 * handlers).
230 */
231__visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
232{
233	struct pt_regs *old_regs = set_irq_regs(regs);
234	struct irq_desc * desc;
235	/* high bit used in ret_from_ code  */
236	unsigned vector = ~regs->orig_ax;
237
238	entering_irq();
239
240	/* entering_irq() tells RCU that we're not quiescent.  Check it. */
241	RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
242
243	desc = __this_cpu_read(vector_irq[vector]);
244
245	if (!handle_irq(desc, regs)) {
246		ack_APIC_irq();
247
248		if (desc != VECTOR_RETRIGGERED) {
249			pr_emerg_ratelimited("%s: %d.%d No irq handler for vector\n",
250					     __func__, smp_processor_id(),
251					     vector);
252		} else {
253			__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
254		}
255	}
256
257	exiting_irq();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
258
259	set_irq_regs(old_regs);
260	return 1;
261}
262
263#ifdef CONFIG_X86_LOCAL_APIC
264/* Function pointer for generic interrupt vector handling */
265void (*x86_platform_ipi_callback)(void) = NULL;
266/*
267 * Handler for X86_PLATFORM_IPI_VECTOR.
268 */
269__visible void __irq_entry smp_x86_platform_ipi(struct pt_regs *regs)
270{
271	struct pt_regs *old_regs = set_irq_regs(regs);
272
273	entering_ack_irq();
274	trace_x86_platform_ipi_entry(X86_PLATFORM_IPI_VECTOR);
275	inc_irq_stat(x86_platform_ipis);
276	if (x86_platform_ipi_callback)
277		x86_platform_ipi_callback();
278	trace_x86_platform_ipi_exit(X86_PLATFORM_IPI_VECTOR);
279	exiting_irq();
280	set_irq_regs(old_regs);
281}
282#endif
283
284#ifdef CONFIG_HAVE_KVM
285static void dummy_handler(void) {}
286static void (*kvm_posted_intr_wakeup_handler)(void) = dummy_handler;
287
288void kvm_set_posted_intr_wakeup_handler(void (*handler)(void))
289{
290	if (handler)
291		kvm_posted_intr_wakeup_handler = handler;
292	else
293		kvm_posted_intr_wakeup_handler = dummy_handler;
 
 
294}
295EXPORT_SYMBOL_GPL(kvm_set_posted_intr_wakeup_handler);
296
297/*
298 * Handler for POSTED_INTERRUPT_VECTOR.
299 */
300__visible void smp_kvm_posted_intr_ipi(struct pt_regs *regs)
301{
302	struct pt_regs *old_regs = set_irq_regs(regs);
303
304	entering_ack_irq();
305	inc_irq_stat(kvm_posted_intr_ipis);
306	exiting_irq();
307	set_irq_regs(old_regs);
308}
309
310/*
311 * Handler for POSTED_INTERRUPT_WAKEUP_VECTOR.
312 */
313__visible void smp_kvm_posted_intr_wakeup_ipi(struct pt_regs *regs)
314{
315	struct pt_regs *old_regs = set_irq_regs(regs);
316
317	entering_ack_irq();
318	inc_irq_stat(kvm_posted_intr_wakeup_ipis);
319	kvm_posted_intr_wakeup_handler();
320	exiting_irq();
321	set_irq_regs(old_regs);
322}
323
324/*
325 * Handler for POSTED_INTERRUPT_NESTED_VECTOR.
326 */
327__visible void smp_kvm_posted_intr_nested_ipi(struct pt_regs *regs)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
328{
329	struct pt_regs *old_regs = set_irq_regs(regs);
 
 
 
 
330
331	entering_ack_irq();
332	inc_irq_stat(kvm_posted_intr_nested_ipis);
333	exiting_irq();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
334	set_irq_regs(old_regs);
335}
336#endif
337
338
339#ifdef CONFIG_HOTPLUG_CPU
340/* A cpu has been removed from cpu_online_mask.  Reset irq affinities. */
341void fixup_irqs(void)
342{
343	unsigned int irr, vector;
344	struct irq_desc *desc;
345	struct irq_data *data;
346	struct irq_chip *chip;
347
348	irq_migrate_all_off_this_cpu();
349
350	/*
351	 * We can remove mdelay() and then send spuriuous interrupts to
352	 * new cpu targets for all the irqs that were handled previously by
353	 * this cpu. While it works, I have seen spurious interrupt messages
354	 * (nothing wrong but still...).
355	 *
356	 * So for now, retain mdelay(1) and check the IRR and then send those
357	 * interrupts to new targets as this cpu is already offlined...
358	 */
359	mdelay(1);
360
361	/*
362	 * We can walk the vector array of this cpu without holding
363	 * vector_lock because the cpu is already marked !online, so
364	 * nothing else will touch it.
365	 */
366	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
367		if (IS_ERR_OR_NULL(__this_cpu_read(vector_irq[vector])))
368			continue;
369
370		irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
371		if (irr  & (1 << (vector % 32))) {
372			desc = __this_cpu_read(vector_irq[vector]);
373
374			raw_spin_lock(&desc->lock);
375			data = irq_desc_get_irq_data(desc);
376			chip = irq_data_get_irq_chip(data);
377			if (chip->irq_retrigger) {
378				chip->irq_retrigger(data);
379				__this_cpu_write(vector_irq[vector], VECTOR_RETRIGGERED);
380			}
381			raw_spin_unlock(&desc->lock);
382		}
383		if (__this_cpu_read(vector_irq[vector]) != VECTOR_RETRIGGERED)
384			__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
385	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
386}
387#endif