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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
3 *
4 * This file contains the lowest level x86_64-specific interrupt
5 * entry and irq statistics code. All the remaining irq logic is
6 * done by the generic kernel/irq/ code and in the
7 * x86_64-specific irq controller code. (e.g. i8259.c and
8 * io_apic.c.)
9 */
10
11#include <linux/kernel_stat.h>
12#include <linux/interrupt.h>
13#include <linux/seq_file.h>
14#include <linux/module.h>
Ashok Raj76e4f662005-06-25 14:55:00 -070015#include <linux/delay.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <asm/uaccess.h>
17#include <asm/io_apic.h>
Andi Kleen95833c82006-01-11 22:44:36 +010018#include <asm/idle.h>
Eric W. Biederman2fb12a92007-02-13 13:26:25 +010019#include <asm/smp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020
21atomic_t irq_err_count;
Linus Torvalds1da177e2005-04-16 15:20:36 -070022
Thomas Gleixner87ebecf2008-01-30 13:30:19 +010023/*
24 * 'what should we do if we get a hw irq event on an illegal vector'.
25 * each architecture has to answer this themselves.
26 */
27void ack_bad_irq(unsigned int irq)
28{
29 printk(KERN_WARNING "unexpected IRQ trap at vector %02x\n", irq);
30 /*
31 * Currently unexpected vectors happen only on SMP and APIC.
32 * We _must_ ack these because every local APIC has only N
33 * irq slots per priority level, and a 'hanging, unacked' IRQ
34 * holds up an irq slot - in excessive cases (when multiple
35 * unexpected vectors occur) that might lock up the APIC
36 * completely.
37 * But don't ack when the APIC is disabled. -AK
38 */
39 if (!disable_apic)
40 ack_APIC_irq();
41}
42
Eric Sandeen4961f102006-06-26 14:00:05 +020043#ifdef CONFIG_DEBUG_STACKOVERFLOW
44/*
45 * Probabilistic stack overflow check:
46 *
47 * Only check the stack in process context, because everything else
48 * runs on the big interrupt stacks. Checking reliably is too expensive,
49 * so we just check from interrupts.
50 */
51static inline void stack_overflow_check(struct pt_regs *regs)
52{
Roman Zippelc9f4f062007-05-09 02:35:16 -070053 u64 curbase = (u64)task_stack_page(current);
Eric Sandeen4961f102006-06-26 14:00:05 +020054 static unsigned long warned = -60*HZ;
55
H. Peter Anvin65ea5b02008-01-30 13:30:56 +010056 if (regs->sp >= curbase && regs->sp <= curbase + THREAD_SIZE &&
57 regs->sp < curbase + sizeof(struct thread_info) + 128 &&
Eric Sandeen4961f102006-06-26 14:00:05 +020058 time_after(jiffies, warned + 60*HZ)) {
H. Peter Anvin65ea5b02008-01-30 13:30:56 +010059 printk("do_IRQ: %s near stack overflow (cur:%Lx,sp:%lx)\n",
60 current->comm, curbase, regs->sp);
Eric Sandeen4961f102006-06-26 14:00:05 +020061 show_stack(NULL,NULL);
62 warned = jiffies;
63 }
64}
65#endif
66
Linus Torvalds1da177e2005-04-16 15:20:36 -070067/*
68 * Generic, controller-independent functions:
69 */
70
71int show_interrupts(struct seq_file *p, void *v)
72{
73 int i = *(loff_t *) v, j;
74 struct irqaction * action;
75 unsigned long flags;
76
77 if (i == 0) {
78 seq_printf(p, " ");
Andrew Morton394e3902006-03-23 03:01:05 -080079 for_each_online_cpu(j)
Jan Beulichbdbdaa72006-06-26 13:59:23 +020080 seq_printf(p, "CPU%-8d",j);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081 seq_putc(p, '\n');
82 }
83
84 if (i < NR_IRQS) {
Jan Beulich072f5d82007-10-17 18:04:40 +020085 unsigned any_count = 0;
86
Linus Torvalds1da177e2005-04-16 15:20:36 -070087 spin_lock_irqsave(&irq_desc[i].lock, flags);
Jan Beulich072f5d82007-10-17 18:04:40 +020088#ifndef CONFIG_SMP
89 any_count = kstat_irqs(i);
90#else
91 for_each_online_cpu(j)
92 any_count |= kstat_cpu(j).irqs[i];
93#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070094 action = irq_desc[i].action;
Jan Beulich072f5d82007-10-17 18:04:40 +020095 if (!action && !any_count)
Linus Torvalds1da177e2005-04-16 15:20:36 -070096 goto skip;
97 seq_printf(p, "%3d: ",i);
98#ifndef CONFIG_SMP
99 seq_printf(p, "%10u ", kstat_irqs(i));
100#else
Andrew Morton394e3902006-03-23 03:01:05 -0800101 for_each_online_cpu(j)
102 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103#endif
Ingo Molnarf29bd1b2006-10-04 02:16:25 -0700104 seq_printf(p, " %8s", irq_desc[i].chip->name);
Ingo Molnara460e742006-10-17 00:10:03 -0700105 seq_printf(p, "-%-8s", irq_desc[i].name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106
Jan Beulich072f5d82007-10-17 18:04:40 +0200107 if (action) {
108 seq_printf(p, " %s", action->name);
109 while ((action = action->next) != NULL)
110 seq_printf(p, ", %s", action->name);
111 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 seq_putc(p, '\n');
113skip:
114 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
115 } else if (i == NR_IRQS) {
116 seq_printf(p, "NMI: ");
Andrew Morton394e3902006-03-23 03:01:05 -0800117 for_each_online_cpu(j)
118 seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count);
Joe Korty38e760a2007-10-17 18:04:40 +0200119 seq_printf(p, " Non-maskable interrupts\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700120 seq_printf(p, "LOC: ");
Andrew Morton394e3902006-03-23 03:01:05 -0800121 for_each_online_cpu(j)
122 seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs);
Joe Korty38e760a2007-10-17 18:04:40 +0200123 seq_printf(p, " Local timer interrupts\n");
124#ifdef CONFIG_SMP
125 seq_printf(p, "RES: ");
126 for_each_online_cpu(j)
127 seq_printf(p, "%10u ", cpu_pda(j)->irq_resched_count);
128 seq_printf(p, " Rescheduling interrupts\n");
129 seq_printf(p, "CAL: ");
130 for_each_online_cpu(j)
131 seq_printf(p, "%10u ", cpu_pda(j)->irq_call_count);
132 seq_printf(p, " function call interrupts\n");
133 seq_printf(p, "TLB: ");
134 for_each_online_cpu(j)
135 seq_printf(p, "%10u ", cpu_pda(j)->irq_tlb_count);
136 seq_printf(p, " TLB shootdowns\n");
137#endif
138 seq_printf(p, "TRM: ");
139 for_each_online_cpu(j)
140 seq_printf(p, "%10u ", cpu_pda(j)->irq_thermal_count);
141 seq_printf(p, " Thermal event interrupts\n");
142 seq_printf(p, "THR: ");
143 for_each_online_cpu(j)
144 seq_printf(p, "%10u ", cpu_pda(j)->irq_threshold_count);
145 seq_printf(p, " Threshold APIC interrupts\n");
146 seq_printf(p, "SPU: ");
147 for_each_online_cpu(j)
148 seq_printf(p, "%10u ", cpu_pda(j)->irq_spurious_count);
149 seq_printf(p, " Spurious interrupts\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151 }
152 return 0;
153}
154
155/*
156 * do_IRQ handles all normal device IRQ's (the special
157 * SMP cross-CPU interrupts have their own specific
158 * handlers).
159 */
160asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
David Howells7d12e782006-10-05 14:55:46 +0100161{
162 struct pt_regs *old_regs = set_irq_regs(regs);
163
Rusty Russell19eadf92006-06-27 02:53:44 -0700164 /* high bit used in ret_from_ code */
H. Peter Anvin65ea5b02008-01-30 13:30:56 +0100165 unsigned vector = ~regs->orig_ax;
Eric W. Biedermane500f572006-10-04 02:16:50 -0700166 unsigned irq;
167
168 exit_idle();
169 irq_enter();
Eric W. Biederman550f2292006-10-04 02:16:51 -0700170 irq = __get_cpu_var(vector_irq)[vector];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171
Eric Sandeen4961f102006-06-26 14:00:05 +0200172#ifdef CONFIG_DEBUG_STACKOVERFLOW
173 stack_overflow_check(regs);
174#endif
Eric W. Biedermand3696cf2006-10-08 23:41:59 -0600175
176 if (likely(irq < NR_IRQS))
177 generic_handle_irq(irq);
Eric W. Biederman2fb12a92007-02-13 13:26:25 +0100178 else {
179 if (!disable_apic)
180 ack_APIC_irq();
181
182 if (printk_ratelimit())
183 printk(KERN_EMERG "%s: %d.%d No irq handler for vector\n",
184 __func__, smp_processor_id(), vector);
185 }
Eric W. Biedermand3696cf2006-10-08 23:41:59 -0600186
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187 irq_exit();
188
David Howells7d12e782006-10-05 14:55:46 +0100189 set_irq_regs(old_regs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 return 1;
191}
192
Ashok Raj76e4f662005-06-25 14:55:00 -0700193#ifdef CONFIG_HOTPLUG_CPU
194void fixup_irqs(cpumask_t map)
195{
196 unsigned int irq;
197 static int warned;
198
199 for (irq = 0; irq < NR_IRQS; irq++) {
200 cpumask_t mask;
Siddha, Suresh B48d8d7e2007-06-25 15:52:35 -0700201 int break_affinity = 0;
202 int set_affinity = 1;
203
Ashok Raj76e4f662005-06-25 14:55:00 -0700204 if (irq == 2)
205 continue;
206
Siddha, Suresh B48d8d7e2007-06-25 15:52:35 -0700207 /* interrupt's are disabled at this point */
208 spin_lock(&irq_desc[irq].lock);
209
210 if (!irq_has_action(irq) ||
211 cpus_equal(irq_desc[irq].affinity, map)) {
212 spin_unlock(&irq_desc[irq].lock);
213 continue;
214 }
215
Ingo Molnara53da522006-06-29 02:24:38 -0700216 cpus_and(mask, irq_desc[irq].affinity, map);
Siddha, Suresh B48d8d7e2007-06-25 15:52:35 -0700217 if (cpus_empty(mask)) {
218 break_affinity = 1;
Ashok Raj76e4f662005-06-25 14:55:00 -0700219 mask = map;
220 }
Siddha, Suresh B48d8d7e2007-06-25 15:52:35 -0700221
222 if (irq_desc[irq].chip->mask)
223 irq_desc[irq].chip->mask(irq);
224
Ingo Molnard1bef4e2006-06-29 02:24:36 -0700225 if (irq_desc[irq].chip->set_affinity)
226 irq_desc[irq].chip->set_affinity(irq, mask);
Siddha, Suresh B48d8d7e2007-06-25 15:52:35 -0700227 else if (!(warned++))
228 set_affinity = 0;
229
230 if (irq_desc[irq].chip->unmask)
231 irq_desc[irq].chip->unmask(irq);
232
233 spin_unlock(&irq_desc[irq].lock);
234
235 if (break_affinity && set_affinity)
236 printk("Broke affinity for irq %i\n", irq);
237 else if (!set_affinity)
Ashok Raj76e4f662005-06-25 14:55:00 -0700238 printk("Cannot set affinity for irq %i\n", irq);
239 }
240
241 /* That doesn't seem sufficient. Give it 1ms. */
242 local_irq_enable();
243 mdelay(1);
244 local_irq_disable();
245}
246#endif
Andi Kleened6b6762005-07-28 21:15:49 -0700247
248extern void call_softirq(void);
249
250asmlinkage void do_softirq(void)
251{
252 __u32 pending;
253 unsigned long flags;
254
255 if (in_interrupt())
256 return;
257
258 local_irq_save(flags);
259 pending = local_softirq_pending();
260 /* Switch to interrupt stack */
Ingo Molnar2601e642006-07-03 00:24:45 -0700261 if (pending) {
Andi Kleened6b6762005-07-28 21:15:49 -0700262 call_softirq();
Ingo Molnar2601e642006-07-03 00:24:45 -0700263 WARN_ON_ONCE(softirq_count());
264 }
Andi Kleened6b6762005-07-28 21:15:49 -0700265 local_irq_restore(flags);
266}