diff options
Diffstat (limited to 'include/linux/hardirq.h')
| -rw-r--r-- | include/linux/hardirq.h | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h new file mode 100644 index 00000000000..ebc712e9106 --- /dev/null +++ b/include/linux/hardirq.h @@ -0,0 +1,106 @@ +#ifndef LINUX_HARDIRQ_H +#define LINUX_HARDIRQ_H + +#include <linux/config.h> +#include <linux/smp_lock.h> +#include <asm/hardirq.h> +#include <asm/system.h> + +/* + * We put the hardirq and softirq counter into the preemption + * counter. The bitmask has the following meaning: + * + * - bits 0-7 are the preemption count (max preemption depth: 256) + * - bits 8-15 are the softirq count (max # of softirqs: 256) + * + * The hardirq count can be overridden per architecture, the default is: + * + * - bits 16-27 are the hardirq count (max # of hardirqs: 4096) + * - ( bit 28 is the PREEMPT_ACTIVE flag. ) + * + * PREEMPT_MASK: 0x000000ff + * SOFTIRQ_MASK: 0x0000ff00 + * HARDIRQ_MASK: 0x0fff0000 + */ +#define PREEMPT_BITS 8 +#define SOFTIRQ_BITS 8 + +#ifndef HARDIRQ_BITS +#define HARDIRQ_BITS 12 +/* + * The hardirq mask has to be large enough to have space for potentially + * all IRQ sources in the system nesting on a single CPU. + */ +#if (1 << HARDIRQ_BITS) < NR_IRQS +# error HARDIRQ_BITS is too low! +#endif +#endif + +#define PREEMPT_SHIFT 0 +#define SOFTIRQ_SHIFT (PREEMPT_SHIFT + PREEMPT_BITS) +#define HARDIRQ_SHIFT (SOFTIRQ_SHIFT + SOFTIRQ_BITS) + +#define __IRQ_MASK(x) ((1UL << (x))-1) + +#define PREEMPT_MASK (__IRQ_MASK(PREEMPT_BITS) << PREEMPT_SHIFT) +#define HARDIRQ_MASK (__IRQ_MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT) +#define SOFTIRQ_MASK (__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT) + +#define PREEMPT_OFFSET (1UL << PREEMPT_SHIFT) +#define SOFTIRQ_OFFSET (1UL << SOFTIRQ_SHIFT) +#define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT) + +#define hardirq_count() (preempt_count() & HARDIRQ_MASK) +#define softirq_count() (preempt_count() & SOFTIRQ_MASK) +#define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK)) + +/* + * Are we doing bottom half or hardware interrupt processing? + * Are we in a softirq context? Interrupt context? + */ +#define in_irq() (hardirq_count()) +#define in_softirq() (softirq_count()) +#define in_interrupt() (irq_count()) + +#if defined(CONFIG_PREEMPT) && !defined(CONFIG_PREEMPT_BKL) +# define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != kernel_locked()) +#else +# define in_atomic() ((preempt_count() & ~PREEMPT_ACTIVE) != 0) +#endif + +#ifdef CONFIG_PREEMPT +# define preemptible() (preempt_count() == 0 && !irqs_disabled()) +# define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1) +#else +# define preemptible() 0 +# define IRQ_EXIT_OFFSET HARDIRQ_OFFSET +#endif + +#ifdef CONFIG_SMP +extern void synchronize_irq(unsigned int irq); +#else +# define synchronize_irq(irq) barrier() +#endif + +#define nmi_enter() irq_enter() +#define nmi_exit() sub_preempt_count(HARDIRQ_OFFSET) + +#ifndef CONFIG_VIRT_CPU_ACCOUNTING +static inline void account_user_vtime(struct task_struct *tsk) +{ +} + +static inline void account_system_vtime(struct task_struct *tsk) +{ +} +#endif + +#define irq_enter() \ + do { \ + account_system_vtime(current); \ + add_preempt_count(HARDIRQ_OFFSET); \ + } while (0) + +extern void irq_exit(void); + +#endif /* LINUX_HARDIRQ_H */ |