Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
[linux-2.6] / 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 #ifdef CONFIG_DEBUG_STACKOVERFLOW
24 /*
25  * Probabilistic stack overflow check:
26  *
27  * Only check the stack in process context, because everything else
28  * runs on the big interrupt stacks. Checking reliably is too expensive,
29  * so we just check from interrupts.
30  */
31 static inline void stack_overflow_check(struct pt_regs *regs)
32 {
33         u64 curbase = (u64)task_stack_page(current);
34         static unsigned long warned = -60*HZ;
35
36         if (regs->rsp >= curbase && regs->rsp <= curbase + THREAD_SIZE &&
37             regs->rsp <  curbase + sizeof(struct thread_info) + 128 &&
38             time_after(jiffies, warned + 60*HZ)) {
39                 printk("do_IRQ: %s near stack overflow (cur:%Lx,rsp:%lx)\n",
40                        current->comm, curbase, regs->rsp);
41                 show_stack(NULL,NULL);
42                 warned = jiffies;
43         }
44 }
45 #endif
46
47 /*
48  * Generic, controller-independent functions:
49  */
50
51 int show_interrupts(struct seq_file *p, void *v)
52 {
53         int i = *(loff_t *) v, j;
54         struct irqaction * action;
55         unsigned long flags;
56
57         if (i == 0) {
58                 seq_printf(p, "           ");
59                 for_each_online_cpu(j)
60                         seq_printf(p, "CPU%-8d",j);
61                 seq_putc(p, '\n');
62         }
63
64         if (i < NR_IRQS) {
65                 spin_lock_irqsave(&irq_desc[i].lock, flags);
66                 action = irq_desc[i].action;
67                 if (!action) 
68                         goto skip;
69                 seq_printf(p, "%3d: ",i);
70 #ifndef CONFIG_SMP
71                 seq_printf(p, "%10u ", kstat_irqs(i));
72 #else
73                 for_each_online_cpu(j)
74                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
75 #endif
76                 seq_printf(p, " %8s", irq_desc[i].chip->name);
77                 seq_printf(p, "-%-8s", irq_desc[i].name);
78
79                 seq_printf(p, "  %s", action->name);
80                 for (action=action->next; action; action = action->next)
81                         seq_printf(p, ", %s", action->name);
82                 seq_putc(p, '\n');
83 skip:
84                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
85         } else if (i == NR_IRQS) {
86                 seq_printf(p, "NMI: ");
87                 for_each_online_cpu(j)
88                         seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count);
89                 seq_putc(p, '\n');
90                 seq_printf(p, "LOC: ");
91                 for_each_online_cpu(j)
92                         seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs);
93                 seq_putc(p, '\n');
94                 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
95         }
96         return 0;
97 }
98
99 /*
100  * do_IRQ handles all normal device IRQ's (the special
101  * SMP cross-CPU interrupts have their own specific
102  * handlers).
103  */
104 asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
105 {
106         struct pt_regs *old_regs = set_irq_regs(regs);
107
108         /* high bit used in ret_from_ code  */
109         unsigned vector = ~regs->orig_rax;
110         unsigned irq;
111
112         exit_idle();
113         irq_enter();
114         irq = __get_cpu_var(vector_irq)[vector];
115
116 #ifdef CONFIG_DEBUG_STACKOVERFLOW
117         stack_overflow_check(regs);
118 #endif
119
120         if (likely(irq < NR_IRQS))
121                 generic_handle_irq(irq);
122         else {
123                 if (!disable_apic)
124                         ack_APIC_irq();
125
126                 if (printk_ratelimit())
127                         printk(KERN_EMERG "%s: %d.%d No irq handler for vector\n",
128                                 __func__, smp_processor_id(), vector);
129         }
130
131         irq_exit();
132
133         set_irq_regs(old_regs);
134         return 1;
135 }
136
137 #ifdef CONFIG_HOTPLUG_CPU
138 void fixup_irqs(cpumask_t map)
139 {
140         unsigned int irq;
141         static int warned;
142
143         for (irq = 0; irq < NR_IRQS; irq++) {
144                 cpumask_t mask;
145                 int break_affinity = 0;
146                 int set_affinity = 1;
147
148                 if (irq == 2)
149                         continue;
150
151                 /* interrupt's are disabled at this point */
152                 spin_lock(&irq_desc[irq].lock);
153
154                 if (!irq_has_action(irq) ||
155                     cpus_equal(irq_desc[irq].affinity, map)) {
156                         spin_unlock(&irq_desc[irq].lock);
157                         continue;
158                 }
159
160                 cpus_and(mask, irq_desc[irq].affinity, map);
161                 if (cpus_empty(mask)) {
162                         break_affinity = 1;
163                         mask = map;
164                 }
165
166                 if (irq_desc[irq].chip->mask)
167                         irq_desc[irq].chip->mask(irq);
168
169                 if (irq_desc[irq].chip->set_affinity)
170                         irq_desc[irq].chip->set_affinity(irq, mask);
171                 else if (!(warned++))
172                         set_affinity = 0;
173
174                 if (irq_desc[irq].chip->unmask)
175                         irq_desc[irq].chip->unmask(irq);
176
177                 spin_unlock(&irq_desc[irq].lock);
178
179                 if (break_affinity && set_affinity)
180                         printk("Broke affinity for irq %i\n", irq);
181                 else if (!set_affinity)
182                         printk("Cannot set affinity for irq %i\n", irq);
183         }
184
185         /* That doesn't seem sufficient.  Give it 1ms. */
186         local_irq_enable();
187         mdelay(1);
188         local_irq_disable();
189 }
190 #endif
191
192 extern void call_softirq(void);
193
194 asmlinkage void do_softirq(void)
195 {
196         __u32 pending;
197         unsigned long flags;
198
199         if (in_interrupt())
200                 return;
201
202         local_irq_save(flags);
203         pending = local_softirq_pending();
204         /* Switch to interrupt stack */
205         if (pending) {
206                 call_softirq();
207                 WARN_ON_ONCE(softirq_count());
208         }
209         local_irq_restore(flags);
210 }