Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/irq/spurious.c |
| 3 | * |
| 4 | * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar |
| 5 | * |
| 6 | * This file contains spurious interrupt handling. |
| 7 | */ |
| 8 | |
| 9 | #include <linux/irq.h> |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/kallsyms.h> |
| 12 | #include <linux/interrupt.h> |
Andi Kleen | 9e094c1 | 2008-01-30 13:32:48 +0100 | [diff] [blame] | 13 | #include <linux/moduleparam.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | |
Andreas Mohr | 83d4e6e | 2006-06-23 02:05:32 -0700 | [diff] [blame] | 15 | static int irqfixup __read_mostly; |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 16 | |
| 17 | /* |
| 18 | * Recovery handler for misrouted interrupts. |
| 19 | */ |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 20 | static int misrouted_irq(int irq) |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 21 | { |
| 22 | int i; |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 23 | int ok = 0; |
| 24 | int work = 0; /* Did we do work for a real IRQ */ |
| 25 | |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 26 | for (i = 1; i < NR_IRQS; i++) { |
| 27 | struct irq_desc *desc = irq_desc + i; |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 28 | struct irqaction *action; |
| 29 | |
| 30 | if (i == irq) /* Already tried */ |
| 31 | continue; |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 32 | |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 33 | spin_lock(&desc->lock); |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 34 | /* Already running on another processor */ |
| 35 | if (desc->status & IRQ_INPROGRESS) { |
| 36 | /* |
| 37 | * Already running: If it is shared get the other |
| 38 | * CPU to go looking for our mystery interrupt too |
| 39 | */ |
Thomas Gleixner | 3cca53b | 2006-07-01 19:29:31 -0700 | [diff] [blame] | 40 | if (desc->action && (desc->action->flags & IRQF_SHARED)) |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 41 | desc->status |= IRQ_PENDING; |
| 42 | spin_unlock(&desc->lock); |
| 43 | continue; |
| 44 | } |
| 45 | /* Honour the normal IRQ locking */ |
| 46 | desc->status |= IRQ_INPROGRESS; |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 47 | action = desc->action; |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 48 | spin_unlock(&desc->lock); |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 49 | |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 50 | while (action) { |
| 51 | /* Only shared IRQ handlers are safe to call */ |
Thomas Gleixner | 3cca53b | 2006-07-01 19:29:31 -0700 | [diff] [blame] | 52 | if (action->flags & IRQF_SHARED) { |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 53 | if (action->handler(i, action->dev_id) == |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 54 | IRQ_HANDLED) |
| 55 | ok = 1; |
| 56 | } |
| 57 | action = action->next; |
| 58 | } |
| 59 | local_irq_disable(); |
| 60 | /* Now clean up the flags */ |
| 61 | spin_lock(&desc->lock); |
| 62 | action = desc->action; |
| 63 | |
| 64 | /* |
| 65 | * While we were looking for a fixup someone queued a real |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 66 | * IRQ clashing with our walk: |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 67 | */ |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 68 | while ((desc->status & IRQ_PENDING) && action) { |
| 69 | /* |
| 70 | * Perform real IRQ processing for the IRQ we deferred |
| 71 | */ |
| 72 | work = 1; |
| 73 | spin_unlock(&desc->lock); |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 74 | handle_IRQ_event(i, action); |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 75 | spin_lock(&desc->lock); |
| 76 | desc->status &= ~IRQ_PENDING; |
| 77 | } |
| 78 | desc->status &= ~IRQ_INPROGRESS; |
| 79 | /* |
| 80 | * If we did actual work for the real IRQ line we must let the |
| 81 | * IRQ controller clean up too |
| 82 | */ |
Thomas Gleixner | dd87eb3 | 2006-06-29 02:24:53 -0700 | [diff] [blame] | 83 | if (work && desc->chip && desc->chip->end) |
Ingo Molnar | d1bef4e | 2006-06-29 02:24:36 -0700 | [diff] [blame] | 84 | desc->chip->end(i); |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 85 | spin_unlock(&desc->lock); |
| 86 | } |
| 87 | /* So the caller can adjust the irq error counts */ |
| 88 | return ok; |
| 89 | } |
| 90 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | /* |
| 92 | * If 99,900 of the previous 100,000 interrupts have not been handled |
| 93 | * then assume that the IRQ is stuck in some manner. Drop a diagnostic |
| 94 | * and try to turn the IRQ off. |
| 95 | * |
| 96 | * (The other 100-of-100,000 interrupts may have been a correctly |
| 97 | * functioning device sharing an IRQ with the failing one) |
| 98 | * |
| 99 | * Called under desc->lock |
| 100 | */ |
| 101 | |
| 102 | static void |
Ingo Molnar | 34ffdb7 | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 103 | __report_bad_irq(unsigned int irq, struct irq_desc *desc, |
| 104 | irqreturn_t action_ret) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | { |
| 106 | struct irqaction *action; |
| 107 | |
| 108 | if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) { |
| 109 | printk(KERN_ERR "irq event %d: bogus return value %x\n", |
| 110 | irq, action_ret); |
| 111 | } else { |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 112 | printk(KERN_ERR "irq %d: nobody cared (try booting with " |
| 113 | "the \"irqpoll\" option)\n", irq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | } |
| 115 | dump_stack(); |
| 116 | printk(KERN_ERR "handlers:\n"); |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 117 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | action = desc->action; |
| 119 | while (action) { |
| 120 | printk(KERN_ERR "[<%p>]", action->handler); |
| 121 | print_symbol(" (%s)", |
| 122 | (unsigned long)action->handler); |
| 123 | printk("\n"); |
| 124 | action = action->next; |
| 125 | } |
| 126 | } |
| 127 | |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 128 | static void |
Ingo Molnar | 34ffdb7 | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 129 | report_bad_irq(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | { |
| 131 | static int count = 100; |
| 132 | |
| 133 | if (count > 0) { |
| 134 | count--; |
| 135 | __report_bad_irq(irq, desc, action_ret); |
| 136 | } |
| 137 | } |
| 138 | |
Linus Torvalds | 92ea772 | 2007-05-24 08:37:14 -0700 | [diff] [blame] | 139 | static inline int try_misrouted_irq(unsigned int irq, struct irq_desc *desc, irqreturn_t action_ret) |
| 140 | { |
| 141 | struct irqaction *action; |
| 142 | |
| 143 | if (!irqfixup) |
| 144 | return 0; |
| 145 | |
| 146 | /* We didn't actually handle the IRQ - see if it was misrouted? */ |
| 147 | if (action_ret == IRQ_NONE) |
| 148 | return 1; |
| 149 | |
| 150 | /* |
| 151 | * But for 'irqfixup == 2' we also do it for handled interrupts if |
| 152 | * they are marked as IRQF_IRQPOLL (or for irq zero, which is the |
| 153 | * traditional PC timer interrupt.. Legacy) |
| 154 | */ |
| 155 | if (irqfixup < 2) |
| 156 | return 0; |
| 157 | |
| 158 | if (!irq) |
| 159 | return 1; |
| 160 | |
| 161 | /* |
| 162 | * Since we don't get the descriptor lock, "action" can |
| 163 | * change under us. We don't really care, but we don't |
| 164 | * want to follow a NULL pointer. So tell the compiler to |
| 165 | * just load it once by using a barrier. |
| 166 | */ |
| 167 | action = desc->action; |
| 168 | barrier(); |
| 169 | return action && (action->flags & IRQF_IRQPOLL); |
| 170 | } |
| 171 | |
Ingo Molnar | 34ffdb7 | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 172 | void note_interrupt(unsigned int irq, struct irq_desc *desc, |
David Howells | 7d12e78 | 2006-10-05 14:55:46 +0100 | [diff] [blame] | 173 | irqreturn_t action_ret) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | { |
Andreas Mohr | 83d4e6e | 2006-06-23 02:05:32 -0700 | [diff] [blame] | 175 | if (unlikely(action_ret != IRQ_HANDLED)) { |
Alan Cox | 4f27c00 | 2007-07-15 23:40:55 -0700 | [diff] [blame] | 176 | /* |
| 177 | * If we are seeing only the odd spurious IRQ caused by |
| 178 | * bus asynchronicity then don't eventually trigger an error, |
| 179 | * otherwise the couter becomes a doomsday timer for otherwise |
| 180 | * working systems |
| 181 | */ |
| 182 | if (jiffies - desc->last_unhandled > HZ/10) |
| 183 | desc->irqs_unhandled = 1; |
| 184 | else |
| 185 | desc->irqs_unhandled++; |
| 186 | desc->last_unhandled = jiffies; |
Andreas Mohr | 83d4e6e | 2006-06-23 02:05:32 -0700 | [diff] [blame] | 187 | if (unlikely(action_ret != IRQ_NONE)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | report_bad_irq(irq, desc, action_ret); |
| 189 | } |
| 190 | |
Linus Torvalds | 92ea772 | 2007-05-24 08:37:14 -0700 | [diff] [blame] | 191 | if (unlikely(try_misrouted_irq(irq, desc, action_ret))) { |
| 192 | int ok = misrouted_irq(irq); |
| 193 | if (action_ret == IRQ_NONE) |
| 194 | desc->irqs_unhandled -= ok; |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 195 | } |
| 196 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | desc->irq_count++; |
Andreas Mohr | 83d4e6e | 2006-06-23 02:05:32 -0700 | [diff] [blame] | 198 | if (likely(desc->irq_count < 100000)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 199 | return; |
| 200 | |
| 201 | desc->irq_count = 0; |
Andreas Mohr | 83d4e6e | 2006-06-23 02:05:32 -0700 | [diff] [blame] | 202 | if (unlikely(desc->irqs_unhandled > 99900)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | /* |
| 204 | * The interrupt is stuck |
| 205 | */ |
| 206 | __report_bad_irq(irq, desc, action_ret); |
| 207 | /* |
| 208 | * Now kill the IRQ |
| 209 | */ |
| 210 | printk(KERN_EMERG "Disabling IRQ #%d\n", irq); |
| 211 | desc->status |= IRQ_DISABLED; |
Thomas Gleixner | 6a6de9e | 2006-06-29 02:24:51 -0700 | [diff] [blame] | 212 | desc->depth = 1; |
Ingo Molnar | d1bef4e | 2006-06-29 02:24:36 -0700 | [diff] [blame] | 213 | desc->chip->disable(irq); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 214 | } |
| 215 | desc->irqs_unhandled = 0; |
| 216 | } |
| 217 | |
Andreas Mohr | 83d4e6e | 2006-06-23 02:05:32 -0700 | [diff] [blame] | 218 | int noirqdebug __read_mostly; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 219 | |
Vivek Goyal | 343cde5 | 2007-01-11 01:52:44 +0100 | [diff] [blame] | 220 | int noirqdebug_setup(char *str) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 221 | { |
| 222 | noirqdebug = 1; |
| 223 | printk(KERN_INFO "IRQ lockup detection disabled\n"); |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 224 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | return 1; |
| 226 | } |
| 227 | |
| 228 | __setup("noirqdebug", noirqdebug_setup); |
Andi Kleen | 9e094c1 | 2008-01-30 13:32:48 +0100 | [diff] [blame] | 229 | module_param(noirqdebug, bool, 0644); |
| 230 | MODULE_PARM_DESC(noirqdebug, "Disable irq lockup detection when true"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 231 | |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 232 | static int __init irqfixup_setup(char *str) |
| 233 | { |
| 234 | irqfixup = 1; |
| 235 | printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n"); |
| 236 | printk(KERN_WARNING "This may impact system performance.\n"); |
Ingo Molnar | 06fcb0c | 2006-06-29 02:24:40 -0700 | [diff] [blame] | 237 | |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 238 | return 1; |
| 239 | } |
| 240 | |
| 241 | __setup("irqfixup", irqfixup_setup); |
Andi Kleen | 9e094c1 | 2008-01-30 13:32:48 +0100 | [diff] [blame] | 242 | module_param(irqfixup, int, 0644); |
| 243 | MODULE_PARM_DESC("irqfixup", "0: No fixup, 1: irqfixup mode 2: irqpoll mode"); |
Alan Cox | 200803d | 2005-06-28 20:45:18 -0700 | [diff] [blame] | 244 | |
| 245 | static int __init irqpoll_setup(char *str) |
| 246 | { |
| 247 | irqfixup = 2; |
| 248 | printk(KERN_WARNING "Misrouted IRQ fixup and polling support " |
| 249 | "enabled\n"); |
| 250 | printk(KERN_WARNING "This may significantly impact system " |
| 251 | "performance\n"); |
| 252 | return 1; |
| 253 | } |
| 254 | |
| 255 | __setup("irqpoll", irqpoll_setup); |