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v5.4
  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/apic.h>
 17#include <asm/io_apic.h>
 18#include <asm/irq.h>
 
 19#include <asm/mce.h>
 20#include <asm/hw_irq.h>
 21#include <asm/desc.h>
 22
 23#define CREATE_TRACE_POINTS
 24#include <asm/trace/irq_vectors.h>
 25
 26DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
 27EXPORT_PER_CPU_SYMBOL(irq_stat);
 28
 29DEFINE_PER_CPU(struct pt_regs *, irq_regs);
 30EXPORT_PER_CPU_SYMBOL(irq_regs);
 31
 32atomic_t irq_err_count;
 33
 
 
 
 34/*
 35 * 'what should we do if we get a hw irq event on an illegal vector'.
 36 * each architecture has to answer this themselves.
 37 */
 38void ack_bad_irq(unsigned int irq)
 39{
 40	if (printk_ratelimit())
 41		pr_err("unexpected IRQ trap at vector %02x\n", irq);
 42
 43	/*
 44	 * Currently unexpected vectors happen only on SMP and APIC.
 45	 * We _must_ ack these because every local APIC has only N
 46	 * irq slots per priority level, and a 'hanging, unacked' IRQ
 47	 * holds up an irq slot - in excessive cases (when multiple
 48	 * unexpected vectors occur) that might lock up the APIC
 49	 * completely.
 50	 * But only ack when the APIC is enabled -AK
 51	 */
 52	ack_APIC_irq();
 53}
 54
 55#define irq_stats(x)		(&per_cpu(irq_stat, x))
 56/*
 57 * /proc/interrupts printing for arch specific interrupts
 58 */
 59int arch_show_interrupts(struct seq_file *p, int prec)
 60{
 61	int j;
 62
 63	seq_printf(p, "%*s: ", prec, "NMI");
 64	for_each_online_cpu(j)
 65		seq_printf(p, "%10u ", irq_stats(j)->__nmi_count);
 66	seq_puts(p, "  Non-maskable interrupts\n");
 67#ifdef CONFIG_X86_LOCAL_APIC
 68	seq_printf(p, "%*s: ", prec, "LOC");
 69	for_each_online_cpu(j)
 70		seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
 71	seq_puts(p, "  Local timer interrupts\n");
 72
 73	seq_printf(p, "%*s: ", prec, "SPU");
 74	for_each_online_cpu(j)
 75		seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
 76	seq_puts(p, "  Spurious interrupts\n");
 77	seq_printf(p, "%*s: ", prec, "PMI");
 78	for_each_online_cpu(j)
 79		seq_printf(p, "%10u ", irq_stats(j)->apic_perf_irqs);
 80	seq_puts(p, "  Performance monitoring interrupts\n");
 81	seq_printf(p, "%*s: ", prec, "IWI");
 82	for_each_online_cpu(j)
 83		seq_printf(p, "%10u ", irq_stats(j)->apic_irq_work_irqs);
 84	seq_puts(p, "  IRQ work interrupts\n");
 85	seq_printf(p, "%*s: ", prec, "RTR");
 86	for_each_online_cpu(j)
 87		seq_printf(p, "%10u ", irq_stats(j)->icr_read_retry_count);
 88	seq_puts(p, "  APIC ICR read retries\n");
 
 89	if (x86_platform_ipi_callback) {
 90		seq_printf(p, "%*s: ", prec, "PLT");
 91		for_each_online_cpu(j)
 92			seq_printf(p, "%10u ", irq_stats(j)->x86_platform_ipis);
 93		seq_puts(p, "  Platform interrupts\n");
 94	}
 95#endif
 96#ifdef CONFIG_SMP
 97	seq_printf(p, "%*s: ", prec, "RES");
 98	for_each_online_cpu(j)
 99		seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
100	seq_puts(p, "  Rescheduling interrupts\n");
101	seq_printf(p, "%*s: ", prec, "CAL");
102	for_each_online_cpu(j)
103		seq_printf(p, "%10u ", irq_stats(j)->irq_call_count);
 
104	seq_puts(p, "  Function call interrupts\n");
105	seq_printf(p, "%*s: ", prec, "TLB");
106	for_each_online_cpu(j)
107		seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
108	seq_puts(p, "  TLB shootdowns\n");
109#endif
110#ifdef CONFIG_X86_THERMAL_VECTOR
111	seq_printf(p, "%*s: ", prec, "TRM");
112	for_each_online_cpu(j)
113		seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
114	seq_puts(p, "  Thermal event interrupts\n");
115#endif
116#ifdef CONFIG_X86_MCE_THRESHOLD
117	seq_printf(p, "%*s: ", prec, "THR");
118	for_each_online_cpu(j)
119		seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
120	seq_puts(p, "  Threshold APIC interrupts\n");
121#endif
122#ifdef CONFIG_X86_MCE_AMD
123	seq_printf(p, "%*s: ", prec, "DFR");
124	for_each_online_cpu(j)
125		seq_printf(p, "%10u ", irq_stats(j)->irq_deferred_error_count);
126	seq_puts(p, "  Deferred Error APIC interrupts\n");
127#endif
128#ifdef CONFIG_X86_MCE
129	seq_printf(p, "%*s: ", prec, "MCE");
130	for_each_online_cpu(j)
131		seq_printf(p, "%10u ", per_cpu(mce_exception_count, j));
132	seq_puts(p, "  Machine check exceptions\n");
133	seq_printf(p, "%*s: ", prec, "MCP");
134	for_each_online_cpu(j)
135		seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
136	seq_puts(p, "  Machine check polls\n");
137#endif
138#ifdef CONFIG_X86_HV_CALLBACK_VECTOR
139	if (test_bit(HYPERVISOR_CALLBACK_VECTOR, system_vectors)) {
140		seq_printf(p, "%*s: ", prec, "HYP");
141		for_each_online_cpu(j)
142			seq_printf(p, "%10u ",
143				   irq_stats(j)->irq_hv_callback_count);
144		seq_puts(p, "  Hypervisor callback interrupts\n");
145	}
146#endif
147#if IS_ENABLED(CONFIG_HYPERV)
148	if (test_bit(HYPERV_REENLIGHTENMENT_VECTOR, system_vectors)) {
149		seq_printf(p, "%*s: ", prec, "HRE");
150		for_each_online_cpu(j)
151			seq_printf(p, "%10u ",
152				   irq_stats(j)->irq_hv_reenlightenment_count);
153		seq_puts(p, "  Hyper-V reenlightenment interrupts\n");
154	}
155	if (test_bit(HYPERV_STIMER0_VECTOR, system_vectors)) {
156		seq_printf(p, "%*s: ", prec, "HVS");
157		for_each_online_cpu(j)
158			seq_printf(p, "%10u ",
159				   irq_stats(j)->hyperv_stimer0_count);
160		seq_puts(p, "  Hyper-V stimer0 interrupts\n");
161	}
162#endif
163	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
164#if defined(CONFIG_X86_IO_APIC)
165	seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
166#endif
167#ifdef CONFIG_HAVE_KVM
168	seq_printf(p, "%*s: ", prec, "PIN");
169	for_each_online_cpu(j)
170		seq_printf(p, "%10u ", irq_stats(j)->kvm_posted_intr_ipis);
171	seq_puts(p, "  Posted-interrupt notification event\n");
172
173	seq_printf(p, "%*s: ", prec, "NPI");
174	for_each_online_cpu(j)
175		seq_printf(p, "%10u ",
176			   irq_stats(j)->kvm_posted_intr_nested_ipis);
177	seq_puts(p, "  Nested posted-interrupt event\n");
178
179	seq_printf(p, "%*s: ", prec, "PIW");
180	for_each_online_cpu(j)
181		seq_printf(p, "%10u ",
182			   irq_stats(j)->kvm_posted_intr_wakeup_ipis);
183	seq_puts(p, "  Posted-interrupt wakeup event\n");
184#endif
185	return 0;
186}
187
188/*
189 * /proc/stat helpers
190 */
191u64 arch_irq_stat_cpu(unsigned int cpu)
192{
193	u64 sum = irq_stats(cpu)->__nmi_count;
194
195#ifdef CONFIG_X86_LOCAL_APIC
196	sum += irq_stats(cpu)->apic_timer_irqs;
197	sum += irq_stats(cpu)->irq_spurious_count;
198	sum += irq_stats(cpu)->apic_perf_irqs;
199	sum += irq_stats(cpu)->apic_irq_work_irqs;
200	sum += irq_stats(cpu)->icr_read_retry_count;
 
201	if (x86_platform_ipi_callback)
202		sum += irq_stats(cpu)->x86_platform_ipis;
203#endif
204#ifdef CONFIG_SMP
205	sum += irq_stats(cpu)->irq_resched_count;
206	sum += irq_stats(cpu)->irq_call_count;
207#endif
208#ifdef CONFIG_X86_THERMAL_VECTOR
209	sum += irq_stats(cpu)->irq_thermal_count;
210#endif
211#ifdef CONFIG_X86_MCE_THRESHOLD
212	sum += irq_stats(cpu)->irq_threshold_count;
213#endif
214#ifdef CONFIG_X86_MCE
215	sum += per_cpu(mce_exception_count, cpu);
216	sum += per_cpu(mce_poll_count, cpu);
217#endif
218	return sum;
219}
220
221u64 arch_irq_stat(void)
222{
223	u64 sum = atomic_read(&irq_err_count);
224	return sum;
225}
226
227
228/*
229 * do_IRQ handles all normal device IRQ's (the special
230 * SMP cross-CPU interrupts have their own specific
231 * handlers).
232 */
233__visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
234{
235	struct pt_regs *old_regs = set_irq_regs(regs);
236	struct irq_desc * desc;
237	/* high bit used in ret_from_ code  */
238	unsigned vector = ~regs->orig_ax;
239
 
 
 
 
 
 
 
 
 
 
 
 
240	entering_irq();
241
242	/* entering_irq() tells RCU that we're not quiescent.  Check it. */
243	RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
244
245	desc = __this_cpu_read(vector_irq[vector]);
246	if (likely(!IS_ERR_OR_NULL(desc))) {
247		if (IS_ENABLED(CONFIG_X86_32))
248			handle_irq(desc, regs);
249		else
250			generic_handle_irq_desc(desc);
251	} else {
252		ack_APIC_irq();
253
254		if (desc == VECTOR_UNUSED) {
255			pr_emerg_ratelimited("%s: %d.%d No irq handler for vector\n",
256					     __func__, smp_processor_id(),
257					     vector);
258		} else {
259			__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
260		}
261	}
262
263	exiting_irq();
264
265	set_irq_regs(old_regs);
266	return 1;
267}
268
269#ifdef CONFIG_X86_LOCAL_APIC
270/* Function pointer for generic interrupt vector handling */
271void (*x86_platform_ipi_callback)(void) = NULL;
272/*
273 * Handler for X86_PLATFORM_IPI_VECTOR.
274 */
275__visible void __irq_entry smp_x86_platform_ipi(struct pt_regs *regs)
276{
277	struct pt_regs *old_regs = set_irq_regs(regs);
278
279	entering_ack_irq();
280	trace_x86_platform_ipi_entry(X86_PLATFORM_IPI_VECTOR);
281	inc_irq_stat(x86_platform_ipis);
 
282	if (x86_platform_ipi_callback)
283		x86_platform_ipi_callback();
284	trace_x86_platform_ipi_exit(X86_PLATFORM_IPI_VECTOR);
 
 
 
 
 
 
 
285	exiting_irq();
286	set_irq_regs(old_regs);
287}
288#endif
289
290#ifdef CONFIG_HAVE_KVM
291static void dummy_handler(void) {}
292static void (*kvm_posted_intr_wakeup_handler)(void) = dummy_handler;
293
294void kvm_set_posted_intr_wakeup_handler(void (*handler)(void))
295{
296	if (handler)
297		kvm_posted_intr_wakeup_handler = handler;
298	else
299		kvm_posted_intr_wakeup_handler = dummy_handler;
300}
301EXPORT_SYMBOL_GPL(kvm_set_posted_intr_wakeup_handler);
302
303/*
304 * Handler for POSTED_INTERRUPT_VECTOR.
305 */
306__visible void smp_kvm_posted_intr_ipi(struct pt_regs *regs)
307{
308	struct pt_regs *old_regs = set_irq_regs(regs);
309
310	entering_ack_irq();
311	inc_irq_stat(kvm_posted_intr_ipis);
312	exiting_irq();
313	set_irq_regs(old_regs);
314}
315
316/*
317 * Handler for POSTED_INTERRUPT_WAKEUP_VECTOR.
318 */
319__visible void smp_kvm_posted_intr_wakeup_ipi(struct pt_regs *regs)
320{
321	struct pt_regs *old_regs = set_irq_regs(regs);
322
323	entering_ack_irq();
324	inc_irq_stat(kvm_posted_intr_wakeup_ipis);
325	kvm_posted_intr_wakeup_handler();
326	exiting_irq();
327	set_irq_regs(old_regs);
328}
 
329
330/*
331 * Handler for POSTED_INTERRUPT_NESTED_VECTOR.
332 */
333__visible void smp_kvm_posted_intr_nested_ipi(struct pt_regs *regs)
334{
335	struct pt_regs *old_regs = set_irq_regs(regs);
336
337	entering_ack_irq();
338	inc_irq_stat(kvm_posted_intr_nested_ipis);
 
 
339	exiting_irq();
340	set_irq_regs(old_regs);
341}
342#endif
343
 
344
345#ifdef CONFIG_HOTPLUG_CPU
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
346/* A cpu has been removed from cpu_online_mask.  Reset irq affinities. */
347void fixup_irqs(void)
348{
349	unsigned int irr, vector;
 
350	struct irq_desc *desc;
351	struct irq_data *data;
352	struct irq_chip *chip;
 
353
354	irq_migrate_all_off_this_cpu();
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
355
356	/*
357	 * We can remove mdelay() and then send spuriuous interrupts to
358	 * new cpu targets for all the irqs that were handled previously by
359	 * this cpu. While it works, I have seen spurious interrupt messages
360	 * (nothing wrong but still...).
361	 *
362	 * So for now, retain mdelay(1) and check the IRR and then send those
363	 * interrupts to new targets as this cpu is already offlined...
364	 */
365	mdelay(1);
366
367	/*
368	 * We can walk the vector array of this cpu without holding
369	 * vector_lock because the cpu is already marked !online, so
370	 * nothing else will touch it.
371	 */
372	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
 
 
373		if (IS_ERR_OR_NULL(__this_cpu_read(vector_irq[vector])))
374			continue;
375
376		irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
377		if (irr  & (1 << (vector % 32))) {
378			desc = __this_cpu_read(vector_irq[vector]);
379
380			raw_spin_lock(&desc->lock);
381			data = irq_desc_get_irq_data(desc);
382			chip = irq_data_get_irq_chip(data);
383			if (chip->irq_retrigger) {
384				chip->irq_retrigger(data);
385				__this_cpu_write(vector_irq[vector], VECTOR_RETRIGGERED);
386			}
387			raw_spin_unlock(&desc->lock);
388		}
389		if (__this_cpu_read(vector_irq[vector]) != VECTOR_RETRIGGERED)
390			__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
391	}
392}
393#endif
v4.6
 
  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/idle.h>
 18#include <asm/mce.h>
 19#include <asm/hw_irq.h>
 20#include <asm/desc.h>
 21
 22#define CREATE_TRACE_POINTS
 23#include <asm/trace/irq_vectors.h>
 24
 25DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat);
 26EXPORT_PER_CPU_SYMBOL(irq_stat);
 27
 28DEFINE_PER_CPU(struct pt_regs *, irq_regs);
 29EXPORT_PER_CPU_SYMBOL(irq_regs);
 30
 31atomic_t irq_err_count;
 32
 33/* Function pointer for generic interrupt vector handling */
 34void (*x86_platform_ipi_callback)(void) = NULL;
 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	ack_APIC_irq();
 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#endif
 92	if (x86_platform_ipi_callback) {
 93		seq_printf(p, "%*s: ", prec, "PLT");
 94		for_each_online_cpu(j)
 95			seq_printf(p, "%10u ", irq_stats(j)->x86_platform_ipis);
 96		seq_puts(p, "  Platform interrupts\n");
 97	}
 
 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					irq_stats(j)->irq_tlb_count);
107	seq_puts(p, "  Function call interrupts\n");
108	seq_printf(p, "%*s: ", prec, "TLB");
109	for_each_online_cpu(j)
110		seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
111	seq_puts(p, "  TLB shootdowns\n");
112#endif
113#ifdef CONFIG_X86_THERMAL_VECTOR
114	seq_printf(p, "%*s: ", prec, "TRM");
115	for_each_online_cpu(j)
116		seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
117	seq_puts(p, "  Thermal event interrupts\n");
118#endif
119#ifdef CONFIG_X86_MCE_THRESHOLD
120	seq_printf(p, "%*s: ", prec, "THR");
121	for_each_online_cpu(j)
122		seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
123	seq_puts(p, "  Threshold APIC interrupts\n");
124#endif
125#ifdef CONFIG_X86_MCE_AMD
126	seq_printf(p, "%*s: ", prec, "DFR");
127	for_each_online_cpu(j)
128		seq_printf(p, "%10u ", irq_stats(j)->irq_deferred_error_count);
129	seq_puts(p, "  Deferred Error APIC interrupts\n");
130#endif
131#ifdef CONFIG_X86_MCE
132	seq_printf(p, "%*s: ", prec, "MCE");
133	for_each_online_cpu(j)
134		seq_printf(p, "%10u ", per_cpu(mce_exception_count, j));
135	seq_puts(p, "  Machine check exceptions\n");
136	seq_printf(p, "%*s: ", prec, "MCP");
137	for_each_online_cpu(j)
138		seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
139	seq_puts(p, "  Machine check polls\n");
140#endif
141#if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
142	if (test_bit(HYPERVISOR_CALLBACK_VECTOR, used_vectors)) {
143		seq_printf(p, "%*s: ", prec, "HYP");
144		for_each_online_cpu(j)
145			seq_printf(p, "%10u ",
146				   irq_stats(j)->irq_hv_callback_count);
147		seq_puts(p, "  Hypervisor callback interrupts\n");
148	}
149#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
150	seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
151#if defined(CONFIG_X86_IO_APIC)
152	seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
153#endif
154#ifdef CONFIG_HAVE_KVM
155	seq_printf(p, "%*s: ", prec, "PIN");
156	for_each_online_cpu(j)
157		seq_printf(p, "%10u ", irq_stats(j)->kvm_posted_intr_ipis);
158	seq_puts(p, "  Posted-interrupt notification event\n");
159
 
 
 
 
 
 
160	seq_printf(p, "%*s: ", prec, "PIW");
161	for_each_online_cpu(j)
162		seq_printf(p, "%10u ",
163			   irq_stats(j)->kvm_posted_intr_wakeup_ipis);
164	seq_puts(p, "  Posted-interrupt wakeup event\n");
165#endif
166	return 0;
167}
168
169/*
170 * /proc/stat helpers
171 */
172u64 arch_irq_stat_cpu(unsigned int cpu)
173{
174	u64 sum = irq_stats(cpu)->__nmi_count;
175
176#ifdef CONFIG_X86_LOCAL_APIC
177	sum += irq_stats(cpu)->apic_timer_irqs;
178	sum += irq_stats(cpu)->irq_spurious_count;
179	sum += irq_stats(cpu)->apic_perf_irqs;
180	sum += irq_stats(cpu)->apic_irq_work_irqs;
181	sum += irq_stats(cpu)->icr_read_retry_count;
182#endif
183	if (x86_platform_ipi_callback)
184		sum += irq_stats(cpu)->x86_platform_ipis;
 
185#ifdef CONFIG_SMP
186	sum += irq_stats(cpu)->irq_resched_count;
187	sum += irq_stats(cpu)->irq_call_count;
188#endif
189#ifdef CONFIG_X86_THERMAL_VECTOR
190	sum += irq_stats(cpu)->irq_thermal_count;
191#endif
192#ifdef CONFIG_X86_MCE_THRESHOLD
193	sum += irq_stats(cpu)->irq_threshold_count;
194#endif
195#ifdef CONFIG_X86_MCE
196	sum += per_cpu(mce_exception_count, cpu);
197	sum += per_cpu(mce_poll_count, cpu);
198#endif
199	return sum;
200}
201
202u64 arch_irq_stat(void)
203{
204	u64 sum = atomic_read(&irq_err_count);
205	return sum;
206}
207
208
209/*
210 * do_IRQ handles all normal device IRQ's (the special
211 * SMP cross-CPU interrupts have their own specific
212 * handlers).
213 */
214__visible unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
215{
216	struct pt_regs *old_regs = set_irq_regs(regs);
217	struct irq_desc * desc;
218	/* high bit used in ret_from_ code  */
219	unsigned vector = ~regs->orig_ax;
220
221	/*
222	 * NB: Unlike exception entries, IRQ entries do not reliably
223	 * handle context tracking in the low-level entry code.  This is
224	 * because syscall entries execute briefly with IRQs on before
225	 * updating context tracking state, so we can take an IRQ from
226	 * kernel mode with CONTEXT_USER.  The low-level entry code only
227	 * updates the context if we came from user mode, so we won't
228	 * switch to CONTEXT_KERNEL.  We'll fix that once the syscall
229	 * code is cleaned up enough that we can cleanly defer enabling
230	 * IRQs.
231	 */
232
233	entering_irq();
234
235	/* entering_irq() tells RCU that we're not quiescent.  Check it. */
236	RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
237
238	desc = __this_cpu_read(vector_irq[vector]);
239
240	if (!handle_irq(desc, regs)) {
 
 
 
 
241		ack_APIC_irq();
242
243		if (desc != VECTOR_RETRIGGERED) {
244			pr_emerg_ratelimited("%s: %d.%d No irq handler for vector\n",
245					     __func__, smp_processor_id(),
246					     vector);
247		} else {
248			__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
249		}
250	}
251
252	exiting_irq();
253
254	set_irq_regs(old_regs);
255	return 1;
256}
257
 
 
 
258/*
259 * Handler for X86_PLATFORM_IPI_VECTOR.
260 */
261void __smp_x86_platform_ipi(void)
262{
 
 
 
 
263	inc_irq_stat(x86_platform_ipis);
264
265	if (x86_platform_ipi_callback)
266		x86_platform_ipi_callback();
267}
268
269__visible void 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	__smp_x86_platform_ipi();
275	exiting_irq();
276	set_irq_regs(old_regs);
277}
 
278
279#ifdef CONFIG_HAVE_KVM
280static void dummy_handler(void) {}
281static void (*kvm_posted_intr_wakeup_handler)(void) = dummy_handler;
282
283void kvm_set_posted_intr_wakeup_handler(void (*handler)(void))
284{
285	if (handler)
286		kvm_posted_intr_wakeup_handler = handler;
287	else
288		kvm_posted_intr_wakeup_handler = dummy_handler;
289}
290EXPORT_SYMBOL_GPL(kvm_set_posted_intr_wakeup_handler);
291
292/*
293 * Handler for POSTED_INTERRUPT_VECTOR.
294 */
295__visible void smp_kvm_posted_intr_ipi(struct pt_regs *regs)
296{
297	struct pt_regs *old_regs = set_irq_regs(regs);
298
299	entering_ack_irq();
300	inc_irq_stat(kvm_posted_intr_ipis);
301	exiting_irq();
302	set_irq_regs(old_regs);
303}
304
305/*
306 * Handler for POSTED_INTERRUPT_WAKEUP_VECTOR.
307 */
308__visible void smp_kvm_posted_intr_wakeup_ipi(struct pt_regs *regs)
309{
310	struct pt_regs *old_regs = set_irq_regs(regs);
311
312	entering_ack_irq();
313	inc_irq_stat(kvm_posted_intr_wakeup_ipis);
314	kvm_posted_intr_wakeup_handler();
315	exiting_irq();
316	set_irq_regs(old_regs);
317}
318#endif
319
320__visible void smp_trace_x86_platform_ipi(struct pt_regs *regs)
 
 
 
321{
322	struct pt_regs *old_regs = set_irq_regs(regs);
323
324	entering_ack_irq();
325	trace_x86_platform_ipi_entry(X86_PLATFORM_IPI_VECTOR);
326	__smp_x86_platform_ipi();
327	trace_x86_platform_ipi_exit(X86_PLATFORM_IPI_VECTOR);
328	exiting_irq();
329	set_irq_regs(old_regs);
330}
 
331
332EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);
333
334#ifdef CONFIG_HOTPLUG_CPU
335
336/* These two declarations are only used in check_irq_vectors_for_cpu_disable()
337 * below, which is protected by stop_machine().  Putting them on the stack
338 * results in a stack frame overflow.  Dynamically allocating could result in a
339 * failure so declare these two cpumasks as global.
340 */
341static struct cpumask affinity_new, online_new;
342
343/*
344 * This cpu is going to be removed and its vectors migrated to the remaining
345 * online cpus.  Check to see if there are enough vectors in the remaining cpus.
346 * This function is protected by stop_machine().
347 */
348int check_irq_vectors_for_cpu_disable(void)
349{
350	unsigned int this_cpu, vector, this_count, count;
351	struct irq_desc *desc;
352	struct irq_data *data;
353	int cpu;
354
355	this_cpu = smp_processor_id();
356	cpumask_copy(&online_new, cpu_online_mask);
357	cpumask_clear_cpu(this_cpu, &online_new);
358
359	this_count = 0;
360	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
361		desc = __this_cpu_read(vector_irq[vector]);
362		if (IS_ERR_OR_NULL(desc))
363			continue;
364		/*
365		 * Protect against concurrent action removal, affinity
366		 * changes etc.
367		 */
368		raw_spin_lock(&desc->lock);
369		data = irq_desc_get_irq_data(desc);
370		cpumask_copy(&affinity_new,
371			     irq_data_get_affinity_mask(data));
372		cpumask_clear_cpu(this_cpu, &affinity_new);
373
374		/* Do not count inactive or per-cpu irqs. */
375		if (!irq_desc_has_action(desc) || irqd_is_per_cpu(data)) {
376			raw_spin_unlock(&desc->lock);
377			continue;
378		}
379
380		raw_spin_unlock(&desc->lock);
381		/*
382		 * A single irq may be mapped to multiple cpu's
383		 * vector_irq[] (for example IOAPIC cluster mode).  In
384		 * this case we have two possibilities:
385		 *
386		 * 1) the resulting affinity mask is empty; that is
387		 * this the down'd cpu is the last cpu in the irq's
388		 * affinity mask, or
389		 *
390		 * 2) the resulting affinity mask is no longer a
391		 * subset of the online cpus but the affinity mask is
392		 * not zero; that is the down'd cpu is the last online
393		 * cpu in a user set affinity mask.
394		 */
395		if (cpumask_empty(&affinity_new) ||
396		    !cpumask_subset(&affinity_new, &online_new))
397			this_count++;
398	}
399
400	count = 0;
401	for_each_online_cpu(cpu) {
402		if (cpu == this_cpu)
403			continue;
404		/*
405		 * We scan from FIRST_EXTERNAL_VECTOR to first system
406		 * vector. If the vector is marked in the used vectors
407		 * bitmap or an irq is assigned to it, we don't count
408		 * it as available.
409		 *
410		 * As this is an inaccurate snapshot anyway, we can do
411		 * this w/o holding vector_lock.
412		 */
413		for (vector = FIRST_EXTERNAL_VECTOR;
414		     vector < first_system_vector; vector++) {
415			if (!test_bit(vector, used_vectors) &&
416			    IS_ERR_OR_NULL(per_cpu(vector_irq, cpu)[vector]))
417			    count++;
418		}
419	}
420
421	if (count < this_count) {
422		pr_warn("CPU %d disable failed: CPU has %u vectors assigned and there are only %u available.\n",
423			this_cpu, this_count, count);
424		return -ERANGE;
425	}
426	return 0;
427}
428
429/* A cpu has been removed from cpu_online_mask.  Reset irq affinities. */
430void fixup_irqs(void)
431{
432	unsigned int irq, vector;
433	static int warned;
434	struct irq_desc *desc;
435	struct irq_data *data;
436	struct irq_chip *chip;
437	int ret;
438
439	for_each_irq_desc(irq, desc) {
440		int break_affinity = 0;
441		int set_affinity = 1;
442		const struct cpumask *affinity;
443
444		if (!desc)
445			continue;
446		if (irq == 2)
447			continue;
448
449		/* interrupt's are disabled at this point */
450		raw_spin_lock(&desc->lock);
451
452		data = irq_desc_get_irq_data(desc);
453		affinity = irq_data_get_affinity_mask(data);
454		if (!irq_has_action(irq) || irqd_is_per_cpu(data) ||
455		    cpumask_subset(affinity, cpu_online_mask)) {
456			raw_spin_unlock(&desc->lock);
457			continue;
458		}
459
460		/*
461		 * Complete the irq move. This cpu is going down and for
462		 * non intr-remapping case, we can't wait till this interrupt
463		 * arrives at this cpu before completing the irq move.
464		 */
465		irq_force_complete_move(desc);
466
467		if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
468			break_affinity = 1;
469			affinity = cpu_online_mask;
470		}
471
472		chip = irq_data_get_irq_chip(data);
473		/*
474		 * The interrupt descriptor might have been cleaned up
475		 * already, but it is not yet removed from the radix tree
476		 */
477		if (!chip) {
478			raw_spin_unlock(&desc->lock);
479			continue;
480		}
481
482		if (!irqd_can_move_in_process_context(data) && chip->irq_mask)
483			chip->irq_mask(data);
484
485		if (chip->irq_set_affinity) {
486			ret = chip->irq_set_affinity(data, affinity, true);
487			if (ret == -ENOSPC)
488				pr_crit("IRQ %d set affinity failed because there are no available vectors.  The device assigned to this IRQ is unstable.\n", irq);
489		} else {
490			if (!(warned++))
491				set_affinity = 0;
492		}
493
494		/*
495		 * We unmask if the irq was not marked masked by the
496		 * core code. That respects the lazy irq disable
497		 * behaviour.
498		 */
499		if (!irqd_can_move_in_process_context(data) &&
500		    !irqd_irq_masked(data) && chip->irq_unmask)
501			chip->irq_unmask(data);
502
503		raw_spin_unlock(&desc->lock);
504
505		if (break_affinity && set_affinity)
506			pr_notice("Broke affinity for irq %i\n", irq);
507		else if (!set_affinity)
508			pr_notice("Cannot set affinity for irq %i\n", irq);
509	}
510
511	/*
512	 * We can remove mdelay() and then send spuriuous interrupts to
513	 * new cpu targets for all the irqs that were handled previously by
514	 * this cpu. While it works, I have seen spurious interrupt messages
515	 * (nothing wrong but still...).
516	 *
517	 * So for now, retain mdelay(1) and check the IRR and then send those
518	 * interrupts to new targets as this cpu is already offlined...
519	 */
520	mdelay(1);
521
522	/*
523	 * We can walk the vector array of this cpu without holding
524	 * vector_lock because the cpu is already marked !online, so
525	 * nothing else will touch it.
526	 */
527	for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
528		unsigned int irr;
529
530		if (IS_ERR_OR_NULL(__this_cpu_read(vector_irq[vector])))
531			continue;
532
533		irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
534		if (irr  & (1 << (vector % 32))) {
535			desc = __this_cpu_read(vector_irq[vector]);
536
537			raw_spin_lock(&desc->lock);
538			data = irq_desc_get_irq_data(desc);
539			chip = irq_data_get_irq_chip(data);
540			if (chip->irq_retrigger) {
541				chip->irq_retrigger(data);
542				__this_cpu_write(vector_irq[vector], VECTOR_RETRIGGERED);
543			}
544			raw_spin_unlock(&desc->lock);
545		}
546		if (__this_cpu_read(vector_irq[vector]) != VECTOR_RETRIGGERED)
547			__this_cpu_write(vector_irq[vector], VECTOR_UNUSED);
548	}
549}
550#endif