1 files changed, 106 insertions, 0 deletions

diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h
new file mode 100644
index 000000000000..ebc712e91066
--- /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 */