2 * Common interrupt code for 32 and 64 bit
5 #include <linux/interrupt.h>
6 #include <linux/kernel_stat.h>
8 #include <linux/seq_file.h>
10 #include <linux/ftrace.h>
11 #include <linux/delay.h>
12 #include <linux/export.h>
15 #include <asm/io_apic.h>
18 #include <asm/hw_irq.h>
21 #define CREATE_TRACE_POINTS
22 #include <asm/trace/irq_vectors.h>
24 DEFINE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t
, irq_stat
);
25 EXPORT_PER_CPU_SYMBOL(irq_stat
);
27 DEFINE_PER_CPU(struct pt_regs
*, irq_regs
);
28 EXPORT_PER_CPU_SYMBOL(irq_regs
);
30 atomic_t irq_err_count
;
32 /* Function pointer for generic interrupt vector handling */
33 void (*x86_platform_ipi_callback
)(void) = NULL
;
36 * 'what should we do if we get a hw irq event on an illegal vector'.
37 * each architecture has to answer this themselves.
39 void ack_bad_irq(unsigned int irq
)
41 if (printk_ratelimit())
42 pr_err("unexpected IRQ trap at vector %02x\n", irq
);
45 * Currently unexpected vectors happen only on SMP and APIC.
46 * We _must_ ack these because every local APIC has only N
47 * irq slots per priority level, and a 'hanging, unacked' IRQ
48 * holds up an irq slot - in excessive cases (when multiple
49 * unexpected vectors occur) that might lock up the APIC
51 * But only ack when the APIC is enabled -AK
56 #define irq_stats(x) (&per_cpu(irq_stat, x))
58 * /proc/interrupts printing for arch specific interrupts
60 int arch_show_interrupts(struct seq_file
*p
, int prec
)
64 seq_printf(p
, "%*s: ", prec
, "NMI");
65 for_each_online_cpu(j
)
66 seq_printf(p
, "%10u ", irq_stats(j
)->__nmi_count
);
67 seq_puts(p
, " Non-maskable interrupts\n");
68 #ifdef CONFIG_X86_LOCAL_APIC
69 seq_printf(p
, "%*s: ", prec
, "LOC");
70 for_each_online_cpu(j
)
71 seq_printf(p
, "%10u ", irq_stats(j
)->apic_timer_irqs
);
72 seq_puts(p
, " Local timer interrupts\n");
74 seq_printf(p
, "%*s: ", prec
, "SPU");
75 for_each_online_cpu(j
)
76 seq_printf(p
, "%10u ", irq_stats(j
)->irq_spurious_count
);
77 seq_puts(p
, " Spurious interrupts\n");
78 seq_printf(p
, "%*s: ", prec
, "PMI");
79 for_each_online_cpu(j
)
80 seq_printf(p
, "%10u ", irq_stats(j
)->apic_perf_irqs
);
81 seq_puts(p
, " Performance monitoring interrupts\n");
82 seq_printf(p
, "%*s: ", prec
, "IWI");
83 for_each_online_cpu(j
)
84 seq_printf(p
, "%10u ", irq_stats(j
)->apic_irq_work_irqs
);
85 seq_puts(p
, " IRQ work interrupts\n");
86 seq_printf(p
, "%*s: ", prec
, "RTR");
87 for_each_online_cpu(j
)
88 seq_printf(p
, "%10u ", irq_stats(j
)->icr_read_retry_count
);
89 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");
98 seq_printf(p
, "%*s: ", prec
, "RES");
99 for_each_online_cpu(j
)
100 seq_printf(p
, "%10u ", irq_stats(j
)->irq_resched_count
);
101 seq_puts(p
, " Rescheduling interrupts\n");
102 seq_printf(p
, "%*s: ", prec
, "CAL");
103 for_each_online_cpu(j
)
104 seq_printf(p
, "%10u ", irq_stats(j
)->irq_call_count
);
105 seq_puts(p
, " Function call interrupts\n");
106 seq_printf(p
, "%*s: ", prec
, "TLB");
107 for_each_online_cpu(j
)
108 seq_printf(p
, "%10u ", irq_stats(j
)->irq_tlb_count
);
109 seq_puts(p
, " TLB shootdowns\n");
111 #ifdef CONFIG_X86_THERMAL_VECTOR
112 seq_printf(p
, "%*s: ", prec
, "TRM");
113 for_each_online_cpu(j
)
114 seq_printf(p
, "%10u ", irq_stats(j
)->irq_thermal_count
);
115 seq_puts(p
, " Thermal event interrupts\n");
117 #ifdef CONFIG_X86_MCE_THRESHOLD
118 seq_printf(p
, "%*s: ", prec
, "THR");
119 for_each_online_cpu(j
)
120 seq_printf(p
, "%10u ", irq_stats(j
)->irq_threshold_count
);
121 seq_puts(p
, " Threshold APIC interrupts\n");
123 #ifdef CONFIG_X86_MCE_AMD
124 seq_printf(p
, "%*s: ", prec
, "DFR");
125 for_each_online_cpu(j
)
126 seq_printf(p
, "%10u ", irq_stats(j
)->irq_deferred_error_count
);
127 seq_puts(p
, " Deferred Error APIC interrupts\n");
129 #ifdef CONFIG_X86_MCE
130 seq_printf(p
, "%*s: ", prec
, "MCE");
131 for_each_online_cpu(j
)
132 seq_printf(p
, "%10u ", per_cpu(mce_exception_count
, j
));
133 seq_puts(p
, " Machine check exceptions\n");
134 seq_printf(p
, "%*s: ", prec
, "MCP");
135 for_each_online_cpu(j
)
136 seq_printf(p
, "%10u ", per_cpu(mce_poll_count
, j
));
137 seq_puts(p
, " Machine check polls\n");
139 #if IS_ENABLED(CONFIG_HYPERV) || defined(CONFIG_XEN)
140 if (test_bit(HYPERVISOR_CALLBACK_VECTOR
, used_vectors
)) {
141 seq_printf(p
, "%*s: ", prec
, "HYP");
142 for_each_online_cpu(j
)
143 seq_printf(p
, "%10u ",
144 irq_stats(j
)->irq_hv_callback_count
);
145 seq_puts(p
, " Hypervisor callback interrupts\n");
148 seq_printf(p
, "%*s: %10u\n", prec
, "ERR", atomic_read(&irq_err_count
));
149 #if defined(CONFIG_X86_IO_APIC)
150 seq_printf(p
, "%*s: %10u\n", prec
, "MIS", atomic_read(&irq_mis_count
));
152 #ifdef CONFIG_HAVE_KVM
153 seq_printf(p
, "%*s: ", prec
, "PIN");
154 for_each_online_cpu(j
)
155 seq_printf(p
, "%10u ", irq_stats(j
)->kvm_posted_intr_ipis
);
156 seq_puts(p
, " Posted-interrupt notification event\n");
158 seq_printf(p
, "%*s: ", prec
, "PIW");
159 for_each_online_cpu(j
)
160 seq_printf(p
, "%10u ",
161 irq_stats(j
)->kvm_posted_intr_wakeup_ipis
);
162 seq_puts(p
, " Posted-interrupt wakeup event\n");
170 u64
arch_irq_stat_cpu(unsigned int cpu
)
172 u64 sum
= irq_stats(cpu
)->__nmi_count
;
174 #ifdef CONFIG_X86_LOCAL_APIC
175 sum
+= irq_stats(cpu
)->apic_timer_irqs
;
176 sum
+= irq_stats(cpu
)->irq_spurious_count
;
177 sum
+= irq_stats(cpu
)->apic_perf_irqs
;
178 sum
+= irq_stats(cpu
)->apic_irq_work_irqs
;
179 sum
+= irq_stats(cpu
)->icr_read_retry_count
;
181 if (x86_platform_ipi_callback
)
182 sum
+= irq_stats(cpu
)->x86_platform_ipis
;
184 sum
+= irq_stats(cpu
)->irq_resched_count
;
185 sum
+= irq_stats(cpu
)->irq_call_count
;
187 #ifdef CONFIG_X86_THERMAL_VECTOR
188 sum
+= irq_stats(cpu
)->irq_thermal_count
;
190 #ifdef CONFIG_X86_MCE_THRESHOLD
191 sum
+= irq_stats(cpu
)->irq_threshold_count
;
193 #ifdef CONFIG_X86_MCE
194 sum
+= per_cpu(mce_exception_count
, cpu
);
195 sum
+= per_cpu(mce_poll_count
, cpu
);
200 u64
arch_irq_stat(void)
202 u64 sum
= atomic_read(&irq_err_count
);
208 * do_IRQ handles all normal device IRQ's (the special
209 * SMP cross-CPU interrupts have their own specific
212 __visible
unsigned int __irq_entry
do_IRQ(struct pt_regs
*regs
)
214 struct pt_regs
*old_regs
= set_irq_regs(regs
);
215 struct irq_desc
* desc
;
216 /* high bit used in ret_from_ code */
217 unsigned vector
= ~regs
->orig_ax
;
220 * NB: Unlike exception entries, IRQ entries do not reliably
221 * handle context tracking in the low-level entry code. This is
222 * because syscall entries execute briefly with IRQs on before
223 * updating context tracking state, so we can take an IRQ from
224 * kernel mode with CONTEXT_USER. The low-level entry code only
225 * updates the context if we came from user mode, so we won't
226 * switch to CONTEXT_KERNEL. We'll fix that once the syscall
227 * code is cleaned up enough that we can cleanly defer enabling
233 /* entering_irq() tells RCU that we're not quiescent. Check it. */
234 RCU_LOCKDEP_WARN(!rcu_is_watching(), "IRQ failed to wake up RCU");
236 desc
= __this_cpu_read(vector_irq
[vector
]);
238 if (!handle_irq(desc
, regs
)) {
241 if (desc
!= VECTOR_RETRIGGERED
) {
242 pr_emerg_ratelimited("%s: %d.%d No irq handler for vector\n",
243 __func__
, smp_processor_id(),
246 __this_cpu_write(vector_irq
[vector
], VECTOR_UNUSED
);
252 set_irq_regs(old_regs
);
257 * Handler for X86_PLATFORM_IPI_VECTOR.
259 void __smp_x86_platform_ipi(void)
261 inc_irq_stat(x86_platform_ipis
);
263 if (x86_platform_ipi_callback
)
264 x86_platform_ipi_callback();
267 __visible
void __irq_entry
smp_x86_platform_ipi(struct pt_regs
*regs
)
269 struct pt_regs
*old_regs
= set_irq_regs(regs
);
272 __smp_x86_platform_ipi();
274 set_irq_regs(old_regs
);
277 #ifdef CONFIG_HAVE_KVM
278 static void dummy_handler(void) {}
279 static void (*kvm_posted_intr_wakeup_handler
)(void) = dummy_handler
;
281 void kvm_set_posted_intr_wakeup_handler(void (*handler
)(void))
284 kvm_posted_intr_wakeup_handler
= handler
;
286 kvm_posted_intr_wakeup_handler
= dummy_handler
;
288 EXPORT_SYMBOL_GPL(kvm_set_posted_intr_wakeup_handler
);
291 * Handler for POSTED_INTERRUPT_VECTOR.
293 __visible
void smp_kvm_posted_intr_ipi(struct pt_regs
*regs
)
295 struct pt_regs
*old_regs
= set_irq_regs(regs
);
298 inc_irq_stat(kvm_posted_intr_ipis
);
300 set_irq_regs(old_regs
);
304 * Handler for POSTED_INTERRUPT_WAKEUP_VECTOR.
306 __visible
void smp_kvm_posted_intr_wakeup_ipi(struct pt_regs
*regs
)
308 struct pt_regs
*old_regs
= set_irq_regs(regs
);
311 inc_irq_stat(kvm_posted_intr_wakeup_ipis
);
312 kvm_posted_intr_wakeup_handler();
314 set_irq_regs(old_regs
);
318 __visible
void __irq_entry
smp_trace_x86_platform_ipi(struct pt_regs
*regs
)
320 struct pt_regs
*old_regs
= set_irq_regs(regs
);
323 trace_x86_platform_ipi_entry(X86_PLATFORM_IPI_VECTOR
);
324 __smp_x86_platform_ipi();
325 trace_x86_platform_ipi_exit(X86_PLATFORM_IPI_VECTOR
);
327 set_irq_regs(old_regs
);
330 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq
);
332 #ifdef CONFIG_HOTPLUG_CPU
334 /* These two declarations are only used in check_irq_vectors_for_cpu_disable()
335 * below, which is protected by stop_machine(). Putting them on the stack
336 * results in a stack frame overflow. Dynamically allocating could result in a
337 * failure so declare these two cpumasks as global.
339 static struct cpumask affinity_new
, online_new
;
342 * This cpu is going to be removed and its vectors migrated to the remaining
343 * online cpus. Check to see if there are enough vectors in the remaining cpus.
344 * This function is protected by stop_machine().
346 int check_irq_vectors_for_cpu_disable(void)
348 unsigned int this_cpu
, vector
, this_count
, count
;
349 struct irq_desc
*desc
;
350 struct irq_data
*data
;
353 this_cpu
= smp_processor_id();
354 cpumask_copy(&online_new
, cpu_online_mask
);
355 cpumask_clear_cpu(this_cpu
, &online_new
);
358 for (vector
= FIRST_EXTERNAL_VECTOR
; vector
< NR_VECTORS
; vector
++) {
359 desc
= __this_cpu_read(vector_irq
[vector
]);
360 if (IS_ERR_OR_NULL(desc
))
363 * Protect against concurrent action removal, affinity
366 raw_spin_lock(&desc
->lock
);
367 data
= irq_desc_get_irq_data(desc
);
368 cpumask_copy(&affinity_new
,
369 irq_data_get_affinity_mask(data
));
370 cpumask_clear_cpu(this_cpu
, &affinity_new
);
372 /* Do not count inactive or per-cpu irqs. */
373 if (!irq_desc_has_action(desc
) || irqd_is_per_cpu(data
)) {
374 raw_spin_unlock(&desc
->lock
);
378 raw_spin_unlock(&desc
->lock
);
380 * A single irq may be mapped to multiple cpu's
381 * vector_irq[] (for example IOAPIC cluster mode). In
382 * this case we have two possibilities:
384 * 1) the resulting affinity mask is empty; that is
385 * this the down'd cpu is the last cpu in the irq's
388 * 2) the resulting affinity mask is no longer a
389 * subset of the online cpus but the affinity mask is
390 * not zero; that is the down'd cpu is the last online
391 * cpu in a user set affinity mask.
393 if (cpumask_empty(&affinity_new
) ||
394 !cpumask_subset(&affinity_new
, &online_new
))
397 /* No need to check any further. */
402 for_each_online_cpu(cpu
) {
406 * We scan from FIRST_EXTERNAL_VECTOR to first system
407 * vector. If the vector is marked in the used vectors
408 * bitmap or an irq is assigned to it, we don't count
411 * As this is an inaccurate snapshot anyway, we can do
412 * this w/o holding vector_lock.
414 for (vector
= FIRST_EXTERNAL_VECTOR
;
415 vector
< first_system_vector
; vector
++) {
416 if (!test_bit(vector
, used_vectors
) &&
417 IS_ERR_OR_NULL(per_cpu(vector_irq
, cpu
)[vector
])) {
418 if (++count
== this_count
)
424 if (count
< this_count
) {
425 pr_warn("CPU %d disable failed: CPU has %u vectors assigned and there are only %u available.\n",
426 this_cpu
, this_count
, count
);
432 /* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
433 void fixup_irqs(void)
435 unsigned int irr
, vector
;
436 struct irq_desc
*desc
;
437 struct irq_data
*data
;
438 struct irq_chip
*chip
;
440 irq_migrate_all_off_this_cpu();
443 * We can remove mdelay() and then send spuriuous interrupts to
444 * new cpu targets for all the irqs that were handled previously by
445 * this cpu. While it works, I have seen spurious interrupt messages
446 * (nothing wrong but still...).
448 * So for now, retain mdelay(1) and check the IRR and then send those
449 * interrupts to new targets as this cpu is already offlined...
454 * We can walk the vector array of this cpu without holding
455 * vector_lock because the cpu is already marked !online, so
456 * nothing else will touch it.
458 for (vector
= FIRST_EXTERNAL_VECTOR
; vector
< NR_VECTORS
; vector
++) {
459 if (IS_ERR_OR_NULL(__this_cpu_read(vector_irq
[vector
])))
462 irr
= apic_read(APIC_IRR
+ (vector
/ 32 * 0x10));
463 if (irr
& (1 << (vector
% 32))) {
464 desc
= __this_cpu_read(vector_irq
[vector
]);
466 raw_spin_lock(&desc
->lock
);
467 data
= irq_desc_get_irq_data(desc
);
468 chip
= irq_data_get_irq_chip(data
);
469 if (chip
->irq_retrigger
) {
470 chip
->irq_retrigger(data
);
471 __this_cpu_write(vector_irq
[vector
], VECTOR_RETRIGGERED
);
473 raw_spin_unlock(&desc
->lock
);
475 if (__this_cpu_read(vector_irq
[vector
]) != VECTOR_RETRIGGERED
)
476 __this_cpu_write(vector_irq
[vector
], VECTOR_UNUSED
);