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
21 atomic_t irq_err_count;
22
23 /* Function pointer for generic interrupt vector handling */
24 void (*x86_platform_ipi_callback)(void) = NULL;
25
26 /*
27 * 'what should we do if we get a hw irq event on an illegal vector'.
28 * each architecture has to answer this themselves.
29 */
ack_bad_irq(unsigned int irq)30 void ack_bad_irq(unsigned int irq)
31 {
32 if (printk_ratelimit())
33 pr_err("unexpected IRQ trap at vector %02x\n", irq);
34
35 /*
36 * Currently unexpected vectors happen only on SMP and APIC.
37 * We _must_ ack these because every local APIC has only N
38 * irq slots per priority level, and a 'hanging, unacked' IRQ
39 * holds up an irq slot - in excessive cases (when multiple
40 * unexpected vectors occur) that might lock up the APIC
41 * completely.
42 * But only ack when the APIC is enabled -AK
43 */
44 ack_APIC_irq();
45 }
46
47 #define irq_stats(x) (&per_cpu(irq_stat, x))
48 /*
49 * /proc/interrupts printing for arch specific interrupts
50 */
arch_show_interrupts(struct seq_file * p,int prec)51 int arch_show_interrupts(struct seq_file *p, int prec)
52 {
53 int j;
54
55 seq_printf(p, "%*s: ", prec, "NMI");
56 for_each_online_cpu(j)
57 seq_printf(p, "%10u ", irq_stats(j)->__nmi_count);
58 seq_printf(p, " Non-maskable interrupts\n");
59 #ifdef CONFIG_X86_LOCAL_APIC
60 seq_printf(p, "%*s: ", prec, "LOC");
61 for_each_online_cpu(j)
62 seq_printf(p, "%10u ", irq_stats(j)->apic_timer_irqs);
63 seq_printf(p, " Local timer interrupts\n");
64
65 seq_printf(p, "%*s: ", prec, "SPU");
66 for_each_online_cpu(j)
67 seq_printf(p, "%10u ", irq_stats(j)->irq_spurious_count);
68 seq_printf(p, " Spurious interrupts\n");
69 seq_printf(p, "%*s: ", prec, "PMI");
70 for_each_online_cpu(j)
71 seq_printf(p, "%10u ", irq_stats(j)->apic_perf_irqs);
72 seq_printf(p, " Performance monitoring interrupts\n");
73 seq_printf(p, "%*s: ", prec, "IWI");
74 for_each_online_cpu(j)
75 seq_printf(p, "%10u ", irq_stats(j)->apic_irq_work_irqs);
76 seq_printf(p, " IRQ work interrupts\n");
77 seq_printf(p, "%*s: ", prec, "RTR");
78 for_each_online_cpu(j)
79 seq_printf(p, "%10u ", irq_stats(j)->icr_read_retry_count);
80 seq_printf(p, " APIC ICR read retries\n");
81 #endif
82 if (x86_platform_ipi_callback) {
83 seq_printf(p, "%*s: ", prec, "PLT");
84 for_each_online_cpu(j)
85 seq_printf(p, "%10u ", irq_stats(j)->x86_platform_ipis);
86 seq_printf(p, " Platform interrupts\n");
87 }
88 #ifdef CONFIG_SMP
89 seq_printf(p, "%*s: ", prec, "RES");
90 for_each_online_cpu(j)
91 seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count);
92 seq_printf(p, " Rescheduling interrupts\n");
93 seq_printf(p, "%*s: ", prec, "CAL");
94 for_each_online_cpu(j)
95 seq_printf(p, "%10u ", irq_stats(j)->irq_call_count -
96 irq_stats(j)->irq_tlb_count);
97 seq_printf(p, " Function call interrupts\n");
98 seq_printf(p, "%*s: ", prec, "TLB");
99 for_each_online_cpu(j)
100 seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count);
101 seq_printf(p, " TLB shootdowns\n");
102 #endif
103 #ifdef CONFIG_X86_THERMAL_VECTOR
104 seq_printf(p, "%*s: ", prec, "TRM");
105 for_each_online_cpu(j)
106 seq_printf(p, "%10u ", irq_stats(j)->irq_thermal_count);
107 seq_printf(p, " Thermal event interrupts\n");
108 #endif
109 #ifdef CONFIG_X86_MCE_THRESHOLD
110 seq_printf(p, "%*s: ", prec, "THR");
111 for_each_online_cpu(j)
112 seq_printf(p, "%10u ", irq_stats(j)->irq_threshold_count);
113 seq_printf(p, " Threshold APIC interrupts\n");
114 #endif
115 #ifdef CONFIG_X86_MCE
116 seq_printf(p, "%*s: ", prec, "MCE");
117 for_each_online_cpu(j)
118 seq_printf(p, "%10u ", per_cpu(mce_exception_count, j));
119 seq_printf(p, " Machine check exceptions\n");
120 seq_printf(p, "%*s: ", prec, "MCP");
121 for_each_online_cpu(j)
122 seq_printf(p, "%10u ", per_cpu(mce_poll_count, j));
123 seq_printf(p, " Machine check polls\n");
124 #endif
125 seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
126 #if defined(CONFIG_X86_IO_APIC)
127 seq_printf(p, "%*s: %10u\n", prec, "MIS", atomic_read(&irq_mis_count));
128 #endif
129 return 0;
130 }
131
132 /*
133 * /proc/stat helpers
134 */
arch_irq_stat_cpu(unsigned int cpu)135 u64 arch_irq_stat_cpu(unsigned int cpu)
136 {
137 u64 sum = irq_stats(cpu)->__nmi_count;
138
139 #ifdef CONFIG_X86_LOCAL_APIC
140 sum += irq_stats(cpu)->apic_timer_irqs;
141 sum += irq_stats(cpu)->irq_spurious_count;
142 sum += irq_stats(cpu)->apic_perf_irqs;
143 sum += irq_stats(cpu)->apic_irq_work_irqs;
144 sum += irq_stats(cpu)->icr_read_retry_count;
145 #endif
146 if (x86_platform_ipi_callback)
147 sum += irq_stats(cpu)->x86_platform_ipis;
148 #ifdef CONFIG_SMP
149 sum += irq_stats(cpu)->irq_resched_count;
150 sum += irq_stats(cpu)->irq_call_count;
151 #endif
152 #ifdef CONFIG_X86_THERMAL_VECTOR
153 sum += irq_stats(cpu)->irq_thermal_count;
154 #endif
155 #ifdef CONFIG_X86_MCE_THRESHOLD
156 sum += irq_stats(cpu)->irq_threshold_count;
157 #endif
158 #ifdef CONFIG_X86_MCE
159 sum += per_cpu(mce_exception_count, cpu);
160 sum += per_cpu(mce_poll_count, cpu);
161 #endif
162 return sum;
163 }
164
arch_irq_stat(void)165 u64 arch_irq_stat(void)
166 {
167 u64 sum = atomic_read(&irq_err_count);
168 return sum;
169 }
170
171
172 /*
173 * do_IRQ handles all normal device IRQ's (the special
174 * SMP cross-CPU interrupts have their own specific
175 * handlers).
176 */
do_IRQ(struct pt_regs * regs)177 unsigned int __irq_entry do_IRQ(struct pt_regs *regs)
178 {
179 struct pt_regs *old_regs = set_irq_regs(regs);
180
181 /* high bit used in ret_from_ code */
182 unsigned vector = ~regs->orig_ax;
183 unsigned irq;
184
185 irq_enter();
186 exit_idle();
187
188 irq = __this_cpu_read(vector_irq[vector]);
189
190 if (!handle_irq(irq, regs)) {
191 ack_APIC_irq();
192
193 if (printk_ratelimit())
194 pr_emerg("%s: %d.%d No irq handler for vector (irq %d)\n",
195 __func__, smp_processor_id(), vector, irq);
196 }
197
198 irq_exit();
199
200 set_irq_regs(old_regs);
201 return 1;
202 }
203
204 /*
205 * Handler for X86_PLATFORM_IPI_VECTOR.
206 */
smp_x86_platform_ipi(struct pt_regs * regs)207 void smp_x86_platform_ipi(struct pt_regs *regs)
208 {
209 struct pt_regs *old_regs = set_irq_regs(regs);
210
211 ack_APIC_irq();
212
213 irq_enter();
214
215 exit_idle();
216
217 inc_irq_stat(x86_platform_ipis);
218
219 if (x86_platform_ipi_callback)
220 x86_platform_ipi_callback();
221
222 irq_exit();
223
224 set_irq_regs(old_regs);
225 }
226
227 #ifdef CONFIG_HAVE_KVM
228 /*
229 * Handler for POSTED_INTERRUPT_VECTOR.
230 */
smp_kvm_posted_intr_ipi(struct pt_regs * regs)231 void smp_kvm_posted_intr_ipi(struct pt_regs *regs)
232 {
233 struct pt_regs *old_regs = set_irq_regs(regs);
234
235 ack_APIC_irq();
236
237 irq_enter();
238
239 exit_idle();
240
241 inc_irq_stat(kvm_posted_intr_ipis);
242
243 irq_exit();
244
245 set_irq_regs(old_regs);
246 }
247 #endif
248
249 EXPORT_SYMBOL_GPL(vector_used_by_percpu_irq);
250
251 #ifdef CONFIG_HOTPLUG_CPU
252 /* A cpu has been removed from cpu_online_mask. Reset irq affinities. */
fixup_irqs(void)253 void fixup_irqs(void)
254 {
255 unsigned int irq, vector;
256 static int warned;
257 struct irq_desc *desc;
258 struct irq_data *data;
259 struct irq_chip *chip;
260
261 for_each_irq_desc(irq, desc) {
262 int break_affinity = 0;
263 int set_affinity = 1;
264 const struct cpumask *affinity;
265
266 if (!desc)
267 continue;
268 if (irq == 2)
269 continue;
270
271 /* interrupt's are disabled at this point */
272 raw_spin_lock(&desc->lock);
273
274 data = irq_desc_get_irq_data(desc);
275 affinity = data->affinity;
276 if (!irq_has_action(irq) || irqd_is_per_cpu(data) ||
277 cpumask_subset(affinity, cpu_online_mask)) {
278 raw_spin_unlock(&desc->lock);
279 continue;
280 }
281
282 /*
283 * Complete the irq move. This cpu is going down and for
284 * non intr-remapping case, we can't wait till this interrupt
285 * arrives at this cpu before completing the irq move.
286 */
287 irq_force_complete_move(irq);
288
289 if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
290 break_affinity = 1;
291 affinity = cpu_online_mask;
292 }
293
294 chip = irq_data_get_irq_chip(data);
295 if (!irqd_can_move_in_process_context(data) && chip->irq_mask)
296 chip->irq_mask(data);
297
298 if (chip->irq_set_affinity)
299 chip->irq_set_affinity(data, affinity, true);
300 else if (!(warned++))
301 set_affinity = 0;
302
303 /*
304 * We unmask if the irq was not marked masked by the
305 * core code. That respects the lazy irq disable
306 * behaviour.
307 */
308 if (!irqd_can_move_in_process_context(data) &&
309 !irqd_irq_masked(data) && chip->irq_unmask)
310 chip->irq_unmask(data);
311
312 raw_spin_unlock(&desc->lock);
313
314 if (break_affinity && set_affinity)
315 pr_notice("Broke affinity for irq %i\n", irq);
316 else if (!set_affinity)
317 pr_notice("Cannot set affinity for irq %i\n", irq);
318 }
319
320 /*
321 * We can remove mdelay() and then send spuriuous interrupts to
322 * new cpu targets for all the irqs that were handled previously by
323 * this cpu. While it works, I have seen spurious interrupt messages
324 * (nothing wrong but still...).
325 *
326 * So for now, retain mdelay(1) and check the IRR and then send those
327 * interrupts to new targets as this cpu is already offlined...
328 */
329 mdelay(1);
330
331 for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
332 unsigned int irr;
333
334 if (__this_cpu_read(vector_irq[vector]) < 0)
335 continue;
336
337 irr = apic_read(APIC_IRR + (vector / 32 * 0x10));
338 if (irr & (1 << (vector % 32))) {
339 irq = __this_cpu_read(vector_irq[vector]);
340
341 desc = irq_to_desc(irq);
342 data = irq_desc_get_irq_data(desc);
343 chip = irq_data_get_irq_chip(data);
344 raw_spin_lock(&desc->lock);
345 if (chip->irq_retrigger)
346 chip->irq_retrigger(data);
347 raw_spin_unlock(&desc->lock);
348 }
349 __this_cpu_write(vector_irq[vector], -1);
350 }
351 }
352 #endif
353