#ifndef LINUX_HARDIRQ_H

#define LINUX_HARDIRQ_H

#include <linux/preempt.h>

#include <linux/smp_lock.h>

#include <linux/lockdep.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

#ifndef MAX_HARDIRQS_PER_CPU

#define MAX_HARDIRQS_PER_CPU NR_IRQS

#endif

/*

 * 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) < MAX_HARDIRQS_PER_CPU

# 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 SOFTIRQ_MASK	(__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT)

#define HARDIRQ_MASK	(__IRQ_MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT)

#define PREEMPT_OFFSET	(1UL << PREEMPT_SHIFT)

#define SOFTIRQ_OFFSET	(1UL << SOFTIRQ_SHIFT)

#define HARDIRQ_OFFSET	(1UL << HARDIRQ_SHIFT)

#if PREEMPT_ACTIVE < (1 << (HARDIRQ_SHIFT + HARDIRQ_BITS))

#error PREEMPT_ACTIVE is too low!

#endif

#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)

# define PREEMPT_INATOMIC_BASE kernel_locked()

# define PREEMPT_CHECK_OFFSET 1

#else

# define PREEMPT_INATOMIC_BASE 0

# define PREEMPT_CHECK_OFFSET 0

#endif

/*

 * Are we running in atomic context?  WARNING: this macro cannot

 * always detect atomic context; in particular, it cannot know about

 * held spinlocks in non-preemptible kernels.  Thus it should not be

 * used in the general case to determine whether sleeping is possible.

 * Do not use in_atomic() in driver code.

 */

#define in_atomic()	((preempt_count() & ~PREEMPT_ACTIVE) != PREEMPT_INATOMIC_BASE)

/*

 * Check whether we were atomic before we did preempt_disable():

 * (used by the scheduler, *after* releasing the kernel lock)

 */

#define in_atomic_preempt_off() \

		((preempt_count() & ~PREEMPT_ACTIVE) != PREEMPT_CHECK_OFFSET)

#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

struct task_struct;

#ifndef CONFIG_VIRT_CPU_ACCOUNTING

static inline void account_system_vtime(struct task_struct *tsk)

{

}

#endif

#if defined(CONFIG_PREEMPT_RCU) && defined(CONFIG_NO_HZ)

extern void rcu_irq_enter(void);

extern void rcu_irq_exit(void);

#else

# define rcu_irq_enter() do { } while (0)

# define rcu_irq_exit() do { } while (0)

#endif /* CONFIG_PREEMPT_RCU */

/*

 * It is safe to do non-atomic ops on ->hardirq_context,

 * because NMI handlers may not preempt and the ops are

 * always balanced, so the interrupted value of ->hardirq_context

 * will always be restored.

 */

#define __irq_enter()					\

	do {						\

		rcu_irq_enter();			\

		account_system_vtime(current);		\

		add_preempt_count(HARDIRQ_OFFSET);	\

		trace_hardirq_enter();			\

	} while (0)

/*

 * Enter irq context (on NO_HZ, update jiffies):

 */

extern void irq_enter(void);

/*

 * Exit irq context without processing softirqs:

 */

#define __irq_exit()					\

	do {						\

		trace_hardirq_exit();			\

		account_system_vtime(current);		\

		sub_preempt_count(HARDIRQ_OFFSET);	\

		rcu_irq_exit();				\

	} while (0)

/*

 * Exit irq context and process softirqs if needed:

 */

extern void irq_exit(void);

#define nmi_enter()		do { lockdep_off(); __irq_enter(); } while (0)

#define nmi_exit()		do { __irq_exit(); lockdep_on(); } while (0)

#endif /* LINUX_HARDIRQ_H */