linux/arch/powerpc/include/asm/irq.h
Benjamin Herrenschmidt 0366a1c70b powerpc/irq: Run softirqs off the top of the irq stack
Nowadays, irq_exit() calls __do_softirq() pretty much directly
instead of calling do_softirq() which switches to the decicated
softirq stack.

This has lead to observed stack overflows on powerpc since we call
irq_enter() and irq_exit() outside of the scope that switches to
the irq stack.

This fixes it by moving the stack switching up a level, making
irq_enter() and irq_exit() run off the irq stack.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-09-25 14:15:36 +10:00

80 lines
1.9 KiB
C

#ifdef __KERNEL__
#ifndef _ASM_POWERPC_IRQ_H
#define _ASM_POWERPC_IRQ_H
/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/irqdomain.h>
#include <linux/threads.h>
#include <linux/list.h>
#include <linux/radix-tree.h>
#include <asm/types.h>
#include <linux/atomic.h>
extern atomic_t ppc_n_lost_interrupts;
/* This number is used when no interrupt has been assigned */
#define NO_IRQ (0)
/* Total number of virq in the platform */
#define NR_IRQS CONFIG_NR_IRQS
/* Same thing, used by the generic IRQ code */
#define NR_IRQS_LEGACY NUM_ISA_INTERRUPTS
extern irq_hw_number_t virq_to_hw(unsigned int virq);
/**
* irq_early_init - Init irq remapping subsystem
*/
extern void irq_early_init(void);
static __inline__ int irq_canonicalize(int irq)
{
return irq;
}
extern int distribute_irqs;
struct irqaction;
struct pt_regs;
#define __ARCH_HAS_DO_SOFTIRQ
#if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
/*
* Per-cpu stacks for handling critical, debug and machine check
* level interrupts.
*/
extern struct thread_info *critirq_ctx[NR_CPUS];
extern struct thread_info *dbgirq_ctx[NR_CPUS];
extern struct thread_info *mcheckirq_ctx[NR_CPUS];
extern void exc_lvl_ctx_init(void);
#else
#define exc_lvl_ctx_init()
#endif
/*
* Per-cpu stacks for handling hard and soft interrupts.
*/
extern struct thread_info *hardirq_ctx[NR_CPUS];
extern struct thread_info *softirq_ctx[NR_CPUS];
extern void irq_ctx_init(void);
extern void call_do_softirq(struct thread_info *tp);
extern void call_do_irq(struct pt_regs *regs, struct thread_info *tp);
extern void do_IRQ(struct pt_regs *regs);
extern void __do_irq(struct pt_regs *regs);
int irq_choose_cpu(const struct cpumask *mask);
#endif /* _ASM_IRQ_H */
#endif /* __KERNEL__ */