[PATCH] lockdep: irqtrace subsystem, x86_64 support
[linux-2.6] / arch / x86_64 / kernel / irq.c
1 /*
2  *      linux/arch/x86_64/kernel/irq.c
3  *
4  *      Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
5  *
6  * This file contains the lowest level x86_64-specific interrupt
7  * entry and irq statistics code. All the remaining irq logic is
8  * done by the generic kernel/irq/ code and in the
9  * x86_64-specific irq controller code. (e.g. i8259.c and
10  * io_apic.c.)
11  */
12
13 #include <linux/kernel_stat.h>
14 #include <linux/interrupt.h>
15 #include <linux/seq_file.h>
16 #include <linux/module.h>
17 #include <linux/delay.h>
18 #include <asm/uaccess.h>
19 #include <asm/io_apic.h>
20 #include <asm/idle.h>
21
22 atomic_t irq_err_count;
23 #ifdef CONFIG_X86_IO_APIC
24 #ifdef APIC_MISMATCH_DEBUG
25 atomic_t irq_mis_count;
26 #endif
27 #endif
28
29 #ifdef CONFIG_DEBUG_STACKOVERFLOW
30 /*
31  * Probabilistic stack overflow check:
32  *
33  * Only check the stack in process context, because everything else
34  * runs on the big interrupt stacks. Checking reliably is too expensive,
35  * so we just check from interrupts.
36  */
37 static inline void stack_overflow_check(struct pt_regs *regs)
38 {
39         u64 curbase = (u64) current->thread_info;
40         static unsigned long warned = -60*HZ;
41
42         if (regs->rsp >= curbase && regs->rsp <= curbase + THREAD_SIZE &&
43             regs->rsp <  curbase + sizeof(struct thread_info) + 128 &&
44             time_after(jiffies, warned + 60*HZ)) {
45                 printk("do_IRQ: %s near stack overflow (cur:%Lx,rsp:%lx)\n",
46                        current->comm, curbase, regs->rsp);
47                 show_stack(NULL,NULL);
48                 warned = jiffies;
49         }
50 }
51 #endif
52
53 /*
54  * Generic, controller-independent functions:
55  */
56
57 int show_interrupts(struct seq_file *p, void *v)
58 {
59         int i = *(loff_t *) v, j;
60         struct irqaction * action;
61         unsigned long flags;
62
63         if (i == 0) {
64                 seq_printf(p, "           ");
65                 for_each_online_cpu(j)
66                         seq_printf(p, "CPU%-8d",j);
67                 seq_putc(p, '\n');
68         }
69
70         if (i < NR_IRQS) {
71                 spin_lock_irqsave(&irq_desc[i].lock, flags);
72                 action = irq_desc[i].action;
73                 if (!action) 
74                         goto skip;
75                 seq_printf(p, "%3d: ",i);
76 #ifndef CONFIG_SMP
77                 seq_printf(p, "%10u ", kstat_irqs(i));
78 #else
79                 for_each_online_cpu(j)
80                         seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
81 #endif
82                 seq_printf(p, " %14s", irq_desc[i].chip->typename);
83
84                 seq_printf(p, "  %s", action->name);
85                 for (action=action->next; action; action = action->next)
86                         seq_printf(p, ", %s", action->name);
87                 seq_putc(p, '\n');
88 skip:
89                 spin_unlock_irqrestore(&irq_desc[i].lock, flags);
90         } else if (i == NR_IRQS) {
91                 seq_printf(p, "NMI: ");
92                 for_each_online_cpu(j)
93                         seq_printf(p, "%10u ", cpu_pda(j)->__nmi_count);
94                 seq_putc(p, '\n');
95 #ifdef CONFIG_X86_LOCAL_APIC
96                 seq_printf(p, "LOC: ");
97                 for_each_online_cpu(j)
98                         seq_printf(p, "%10u ", cpu_pda(j)->apic_timer_irqs);
99                 seq_putc(p, '\n');
100 #endif
101                 seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
102 #ifdef CONFIG_X86_IO_APIC
103 #ifdef APIC_MISMATCH_DEBUG
104                 seq_printf(p, "MIS: %10u\n", atomic_read(&irq_mis_count));
105 #endif
106 #endif
107         }
108         return 0;
109 }
110
111 /*
112  * do_IRQ handles all normal device IRQ's (the special
113  * SMP cross-CPU interrupts have their own specific
114  * handlers).
115  */
116 asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
117 {       
118         /* high bit used in ret_from_ code  */
119         unsigned irq = ~regs->orig_rax;
120
121         if (unlikely(irq >= NR_IRQS)) {
122                 printk(KERN_EMERG "%s: cannot handle IRQ %d\n",
123                                         __FUNCTION__, irq);
124                 BUG();
125         }
126
127         exit_idle();
128         irq_enter();
129 #ifdef CONFIG_DEBUG_STACKOVERFLOW
130         stack_overflow_check(regs);
131 #endif
132         __do_IRQ(irq, regs);
133         irq_exit();
134
135         return 1;
136 }
137
138 #ifdef CONFIG_HOTPLUG_CPU
139 void fixup_irqs(cpumask_t map)
140 {
141         unsigned int irq;
142         static int warned;
143
144         for (irq = 0; irq < NR_IRQS; irq++) {
145                 cpumask_t mask;
146                 if (irq == 2)
147                         continue;
148
149                 cpus_and(mask, irq_desc[irq].affinity, map);
150                 if (any_online_cpu(mask) == NR_CPUS) {
151                         printk("Breaking affinity for irq %i\n", irq);
152                         mask = map;
153                 }
154                 if (irq_desc[irq].chip->set_affinity)
155                         irq_desc[irq].chip->set_affinity(irq, mask);
156                 else if (irq_desc[irq].action && !(warned++))
157                         printk("Cannot set affinity for irq %i\n", irq);
158         }
159
160         /* That doesn't seem sufficient.  Give it 1ms. */
161         local_irq_enable();
162         mdelay(1);
163         local_irq_disable();
164 }
165 #endif
166
167 extern void call_softirq(void);
168
169 asmlinkage void do_softirq(void)
170 {
171         __u32 pending;
172         unsigned long flags;
173
174         if (in_interrupt())
175                 return;
176
177         local_irq_save(flags);
178         pending = local_softirq_pending();
179         /* Switch to interrupt stack */
180         if (pending) {
181                 call_softirq();
182                 WARN_ON_ONCE(softirq_count());
183         }
184         local_irq_restore(flags);
185 }
186 EXPORT_SYMBOL(do_softirq);