linux_dsm_epyc7002/arch/mips/kernel/irq.c
Matt Redfearn fe8bd18ffe MIPS: Introduce irq_stack
Allocate a per-cpu irq stack for use within interrupt handlers.

Also add a utility function on_irq_stack to determine if a given stack
pointer is within the irq stack for that cpu.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Acked-by: Jason A. Donenfeld <jason@zx2c4.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Aaron Tomlin <atomlin@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/14740/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-01-03 16:34:34 +01:00

110 lines
2.4 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Code to handle x86 style IRQs plus some generic interrupt stuff.
*
* Copyright (C) 1992 Linus Torvalds
* Copyright (C) 1994 - 2000 Ralf Baechle
*/
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
#include <linux/proc_fs.h>
#include <linux/mm.h>
#include <linux/random.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/kallsyms.h>
#include <linux/kgdb.h>
#include <linux/ftrace.h>
#include <linux/atomic.h>
#include <linux/uaccess.h>
void *irq_stack[NR_CPUS];
/*
* 'what should we do if we get a hw irq event on an illegal vector'.
* each architecture has to answer this themselves.
*/
void ack_bad_irq(unsigned int irq)
{
printk("unexpected IRQ # %d\n", irq);
}
atomic_t irq_err_count;
int arch_show_interrupts(struct seq_file *p, int prec)
{
seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
return 0;
}
asmlinkage void spurious_interrupt(void)
{
atomic_inc(&irq_err_count);
}
void __init init_IRQ(void)
{
int i;
for (i = 0; i < NR_IRQS; i++)
irq_set_noprobe(i);
if (cpu_has_veic)
clear_c0_status(ST0_IM);
arch_init_irq();
for_each_possible_cpu(i) {
int irq_pages = IRQ_STACK_SIZE / PAGE_SIZE;
void *s = (void *)__get_free_pages(GFP_KERNEL, irq_pages);
irq_stack[i] = s;
pr_debug("CPU%d IRQ stack at 0x%p - 0x%p\n", i,
irq_stack[i], irq_stack[i] + IRQ_STACK_SIZE);
}
}
#ifdef CONFIG_DEBUG_STACKOVERFLOW
static inline void check_stack_overflow(void)
{
unsigned long sp;
__asm__ __volatile__("move %0, $sp" : "=r" (sp));
sp &= THREAD_MASK;
/*
* Check for stack overflow: is there less than STACK_WARN free?
* STACK_WARN is defined as 1/8 of THREAD_SIZE by default.
*/
if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
printk("do_IRQ: stack overflow: %ld\n",
sp - sizeof(struct thread_info));
dump_stack();
}
}
#else
static inline void check_stack_overflow(void) {}
#endif
/*
* do_IRQ handles all normal device IRQ's (the special
* SMP cross-CPU interrupts have their own specific
* handlers).
*/
void __irq_entry do_IRQ(unsigned int irq)
{
irq_enter();
check_stack_overflow();
generic_handle_irq(irq);
irq_exit();
}