Merge branch 'linus' into cpus4096
[pandora-kernel.git] / arch / x86 / kernel / irq_64.c
1 /*
2  *      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>
15 #include <linux/delay.h>
16 #include <asm/uaccess.h>
17 #include <asm/io_apic.h>
18 #include <asm/idle.h>
19 #include <asm/smp.h>
20
21 atomic_t irq_err_count;
22
23 /*
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  */
27 void 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
43 #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  */
51 static inline void stack_overflow_check(struct pt_regs *regs)
52 {
53         u64 curbase = (u64)task_stack_page(current);
54         static unsigned long warned = -60*HZ;
55
56         if (regs->sp >= curbase && regs->sp <= curbase + THREAD_SIZE &&
57             regs->sp <  curbase + sizeof(struct thread_info) + 128 &&
58             time_after(jiffies, warned + 60*HZ)) {
59                 printk("do_IRQ: %s near stack overflow (cur:%Lx,sp:%lx)\n",
60                        current->comm, curbase, regs->sp);
61                 show_stack(NULL,NULL);
62                 warned = jiffies;
63         }
64 }
65 #endif
66
67 /*
68  * Generic, controller-independent functions:
69  */
70
71 int 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, "           ");
79                 for_each_online_cpu(j)
80                         seq_printf(p, "CPU%-8d",j);
81                 seq_putc(p, '\n');
82         }
83
84         if (i < NR_IRQS) {
85                 unsigned any_count = 0;
86
87                 spin_lock_irqsave(&irq_desc[i].lock, flags);
88 #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
94                 action = irq_desc[i].action;
95                 if (!action && !any_count)
96                         goto skip;
97                 seq_printf(p, "%3d: ",i);
98 #ifndef CONFIG_SMP
99                 seq_printf(p, "%10u ", kstat_irqs(i));
100 #else
101                 for_each_online_cpu(j)
102                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
103 #endif
104                 seq_printf(p, " %8s", irq_desc[i].chip->name);
105                 seq_printf(p, "-%-8s", irq_desc[i].name);
106
107                 if (action) {
108                         seq_printf(p, "  %s", action->name);
109                         while ((action = action->next) != NULL)
110                                 seq_printf(p, ", %s", action->name);
111                 }
112                 seq_putc(p, '\n');
113 skip:
114                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
115         } else if (i == NR_IRQS) {
116                 seq_printf(p, "NMI: ");
117                 for_each_online_cpu(j)
118                         seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count);
119                 seq_printf(p, "  Non-maskable interrupts\n");
120                 seq_printf(p, "LOC: ");
121                 for_each_online_cpu(j)
122                         seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs);
123                 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 #ifdef CONFIG_X86_MCE
139                 seq_printf(p, "TRM: ");
140                 for_each_online_cpu(j)
141                         seq_printf(p, "%10u ", cpu_pda(j)->irq_thermal_count);
142                 seq_printf(p, "  Thermal event interrupts\n");
143                 seq_printf(p, "THR: ");
144                 for_each_online_cpu(j)
145                         seq_printf(p, "%10u ", cpu_pda(j)->irq_threshold_count);
146                 seq_printf(p, "  Threshold APIC interrupts\n");
147 #endif
148                 seq_printf(p, "SPU: ");
149                 for_each_online_cpu(j)
150                         seq_printf(p, "%10u ", cpu_pda(j)->irq_spurious_count);
151                 seq_printf(p, "  Spurious interrupts\n");
152                 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
153         }
154         return 0;
155 }
156
157 /*
158  * /proc/stat helpers
159  */
160 u64 arch_irq_stat_cpu(unsigned int cpu)
161 {
162         u64 sum = cpu_pda(cpu)->__nmi_count;
163
164         sum += cpu_pda(cpu)->apic_timer_irqs;
165 #ifdef CONFIG_SMP
166         sum += cpu_pda(cpu)->irq_resched_count;
167         sum += cpu_pda(cpu)->irq_call_count;
168         sum += cpu_pda(cpu)->irq_tlb_count;
169 #endif
170 #ifdef CONFIG_X86_MCE
171         sum += cpu_pda(cpu)->irq_thermal_count;
172         sum += cpu_pda(cpu)->irq_threshold_count;
173 #endif
174         sum += cpu_pda(cpu)->irq_spurious_count;
175         return sum;
176 }
177
178 u64 arch_irq_stat(void)
179 {
180         return atomic_read(&irq_err_count);
181 }
182
183 /*
184  * do_IRQ handles all normal device IRQ's (the special
185  * SMP cross-CPU interrupts have their own specific
186  * handlers).
187  */
188 asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
189 {
190         struct pt_regs *old_regs = set_irq_regs(regs);
191
192         /* high bit used in ret_from_ code  */
193         unsigned vector = ~regs->orig_ax;
194         unsigned irq;
195
196         exit_idle();
197         irq_enter();
198         irq = __get_cpu_var(vector_irq)[vector];
199
200 #ifdef CONFIG_DEBUG_STACKOVERFLOW
201         stack_overflow_check(regs);
202 #endif
203
204         if (likely(irq < NR_IRQS))
205                 generic_handle_irq(irq);
206         else {
207                 if (!disable_apic)
208                         ack_APIC_irq();
209
210                 if (printk_ratelimit())
211                         printk(KERN_EMERG "%s: %d.%d No irq handler for vector\n",
212                                 __func__, smp_processor_id(), vector);
213         }
214
215         irq_exit();
216
217         set_irq_regs(old_regs);
218         return 1;
219 }
220
221 #ifdef CONFIG_HOTPLUG_CPU
222 void fixup_irqs(cpumask_t map)
223 {
224         unsigned int irq;
225         static int warned;
226
227         for (irq = 0; irq < NR_IRQS; irq++) {
228                 cpumask_t mask;
229                 int break_affinity = 0;
230                 int set_affinity = 1;
231
232                 if (irq == 2)
233                         continue;
234
235                 /* interrupt's are disabled at this point */
236                 spin_lock(&irq_desc[irq].lock);
237
238                 if (!irq_has_action(irq) ||
239                     cpus_equal(irq_desc[irq].affinity, map)) {
240                         spin_unlock(&irq_desc[irq].lock);
241                         continue;
242                 }
243
244                 cpus_and(mask, irq_desc[irq].affinity, map);
245                 if (cpus_empty(mask)) {
246                         break_affinity = 1;
247                         mask = map;
248                 }
249
250                 if (irq_desc[irq].chip->mask)
251                         irq_desc[irq].chip->mask(irq);
252
253                 if (irq_desc[irq].chip->set_affinity)
254                         irq_desc[irq].chip->set_affinity(irq, mask);
255                 else if (!(warned++))
256                         set_affinity = 0;
257
258                 if (irq_desc[irq].chip->unmask)
259                         irq_desc[irq].chip->unmask(irq);
260
261                 spin_unlock(&irq_desc[irq].lock);
262
263                 if (break_affinity && set_affinity)
264                         printk("Broke affinity for irq %i\n", irq);
265                 else if (!set_affinity)
266                         printk("Cannot set affinity for irq %i\n", irq);
267         }
268
269         /* That doesn't seem sufficient.  Give it 1ms. */
270         local_irq_enable();
271         mdelay(1);
272         local_irq_disable();
273 }
274 #endif
275
276 extern void call_softirq(void);
277
278 asmlinkage void do_softirq(void)
279 {
280         __u32 pending;
281         unsigned long flags;
282
283         if (in_interrupt())
284                 return;
285
286         local_irq_save(flags);
287         pending = local_softirq_pending();
288         /* Switch to interrupt stack */
289         if (pending) {
290                 call_softirq();
291                 WARN_ON_ONCE(softirq_count());
292         }
293         local_irq_restore(flags);
294 }