linux_dsm_epyc7002/arch/s390/kernel/irq.c
Paul Mackerras 829035fd70 [PATCH] lockdep: irqtrace subsystem, move account_system_vtime() calls into kernel/softirq.c
At the moment, powerpc and s390 have their own versions of do_softirq which
include local_bh_disable() and __local_bh_enable() calls.  They end up
calling __do_softirq (in kernel/softirq.c) which also does
local_bh_disable/enable.

Apparently the two levels of disable/enable trigger a warning from some
validation code that Ingo is working on, and he would like to see the outer
level removed.  But to do that, we have to move the account_system_vtime
calls that are currently in the arch do_softirq() implementations for
powerpc and s390 into the generic __do_softirq() (this is a no-op for other
archs because account_system_vtime is defined to be an empty inline
function on all other archs).  This patch does that.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03 15:27:10 -07:00

98 lines
2.1 KiB
C

/*
* arch/s390/kernel/irq.c
*
* S390 version
* Copyright (C) 2004 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
*
* This file contains interrupt related functions.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/kernel_stat.h>
#include <linux/interrupt.h>
#include <linux/seq_file.h>
#include <linux/cpu.h>
/*
* show_interrupts is needed by /proc/interrupts.
*/
int show_interrupts(struct seq_file *p, void *v)
{
static const char *intrclass_names[] = { "EXT", "I/O", };
int i = *(loff_t *) v, j;
if (i == 0) {
seq_puts(p, " ");
for_each_online_cpu(j)
seq_printf(p, "CPU%d ",j);
seq_putc(p, '\n');
}
if (i < NR_IRQS) {
seq_printf(p, "%s: ", intrclass_names[i]);
#ifndef CONFIG_SMP
seq_printf(p, "%10u ", kstat_irqs(i));
#else
for_each_online_cpu(j)
seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
#endif
seq_putc(p, '\n');
}
return 0;
}
/*
* For compatibilty only. S/390 specific setup of interrupts et al. is done
* much later in init_channel_subsystem().
*/
void __init
init_IRQ(void)
{
/* nothing... */
}
/*
* Switch to the asynchronous interrupt stack for softirq execution.
*/
extern void __do_softirq(void);
asmlinkage void do_softirq(void)
{
unsigned long flags, old, new;
if (in_interrupt())
return;
local_irq_save(flags);
if (local_softirq_pending()) {
/* Get current stack pointer. */
asm volatile("la %0,0(15)" : "=a" (old));
/* Check against async. stack address range. */
new = S390_lowcore.async_stack;
if (((new - old) >> (PAGE_SHIFT + THREAD_ORDER)) != 0) {
/* Need to switch to the async. stack. */
new -= STACK_FRAME_OVERHEAD;
((struct stack_frame *) new)->back_chain = old;
asm volatile(" la 15,0(%0)\n"
" basr 14,%2\n"
" la 15,0(%1)\n"
: : "a" (new), "a" (old),
"a" (__do_softirq)
: "0", "1", "2", "3", "4", "5", "14",
"cc", "memory" );
} else
/* We are already on the async stack. */
__do_softirq();
}
local_irq_restore(flags);
}
EXPORT_SYMBOL(do_softirq);