]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blame - arch/s390/kernel/irq.c
Merge Christoph's freeze cleanup patch
[mirror_ubuntu-artful-kernel.git] / arch / s390 / kernel / irq.c
CommitLineData
1da177e4
LT
1/*
2 * arch/s390/kernel/irq.c
3 *
4 * S390 version
5 * Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
6 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
7 *
8 * This file contains interrupt related functions.
9 */
10
11#include <linux/module.h>
12#include <linux/kernel.h>
13#include <linux/kernel_stat.h>
14#include <linux/interrupt.h>
15#include <linux/seq_file.h>
16#include <linux/cpu.h>
17
18/*
19 * show_interrupts is needed by /proc/interrupts.
20 */
21int show_interrupts(struct seq_file *p, void *v)
22{
23 static const char *intrclass_names[] = { "EXT", "I/O", };
24 int i = *(loff_t *) v, j;
25
26 if (i == 0) {
27 seq_puts(p, " ");
28 for_each_online_cpu(j)
29 seq_printf(p, "CPU%d ",j);
30 seq_putc(p, '\n');
31 }
32
33 if (i < NR_IRQS) {
34 seq_printf(p, "%s: ", intrclass_names[i]);
35#ifndef CONFIG_SMP
36 seq_printf(p, "%10u ", kstat_irqs(i));
37#else
38 for_each_online_cpu(j)
39 seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
40#endif
41 seq_putc(p, '\n');
42
43 }
44
45 return 0;
46}
47
48/*
49 * For compatibilty only. S/390 specific setup of interrupts et al. is done
50 * much later in init_channel_subsystem().
51 */
52void __init
53init_IRQ(void)
54{
55 /* nothing... */
56}
57
58/*
59 * Switch to the asynchronous interrupt stack for softirq execution.
60 */
61extern void __do_softirq(void);
62
63asmlinkage void do_softirq(void)
64{
65 unsigned long flags, old, new;
66
67 if (in_interrupt())
68 return;
69
70 local_irq_save(flags);
71
72 account_system_vtime(current);
73
74 local_bh_disable();
75
76 if (local_softirq_pending()) {
77 /* Get current stack pointer. */
78 asm volatile("la %0,0(15)" : "=a" (old));
79 /* Check against async. stack address range. */
80 new = S390_lowcore.async_stack;
81 if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
82 /* Need to switch to the async. stack. */
83 new -= STACK_FRAME_OVERHEAD;
84 ((struct stack_frame *) new)->back_chain = old;
85
86 asm volatile(" la 15,0(%0)\n"
87 " basr 14,%2\n"
88 " la 15,0(%1)\n"
89 : : "a" (new), "a" (old),
90 "a" (__do_softirq)
91 : "0", "1", "2", "3", "4", "5", "14",
92 "cc", "memory" );
93 } else
94 /* We are already on the async stack. */
95 __do_softirq();
96 }
97
98 account_system_vtime(current);
99
100 __local_bh_enable();
101
102 local_irq_restore(flags);
103}
104
105EXPORT_SYMBOL(do_softirq);