diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
new file mode 100644
index 0000000..22c4469
--- /dev/null
+++ b/include/linux/perf_counter.h
@@ -0,0 +1,171 @@
+/*
+ *  Performance counters:
+ *
+ *   Copyright(C) 2008, Thomas Gleixner <tglx@linutronix.de>
+ *   Copyright(C) 2008, Red Hat, Inc., Ingo Molnar
+ *
+ *  Data type definitions, declarations, prototypes.
+ *
+ *  Started by: Thomas Gleixner and Ingo Molnar
+ *
+ *  For licencing details see kernel-base/COPYING
+ */
+#ifndef _LINUX_PERF_COUNTER_H
+#define _LINUX_PERF_COUNTER_H
+
+#include <asm/atomic.h>
+
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/rculist.h>
+#include <linux/rcupdate.h>
+#include <linux/spinlock.h>
+
+struct task_struct;
+
+/*
+ * Generalized hardware event types, used by the hw_event_type parameter
+ * of the sys_perf_counter_open() syscall:
+ */
+enum hw_event_types {
+	PERF_COUNT_CYCLES,
+	PERF_COUNT_INSTRUCTIONS,
+	PERF_COUNT_CACHE_REFERENCES,
+	PERF_COUNT_CACHE_MISSES,
+	PERF_COUNT_BRANCH_INSTRUCTIONS,
+	PERF_COUNT_BRANCH_MISSES,
+	/*
+	 * If this bit is set in the type, then trigger NMI sampling:
+	 */
+	PERF_COUNT_NMI			= (1 << 30),
+};
+
+/*
+ * IRQ-notification data record type:
+ */
+enum perf_record_type {
+	PERF_RECORD_SIMPLE,
+	PERF_RECORD_IRQ,
+	PERF_RECORD_GROUP,
+};
+
+/**
+ * struct hw_perf_counter - performance counter hardware details
+ */
+struct hw_perf_counter {
+	u64			config;
+	unsigned long		config_base;
+	unsigned long		counter_base;
+	int			nmi;
+	unsigned int		idx;
+	u64			prev_count;
+	s32			next_count;
+	u64			irq_period;
+};
+
+/*
+ * Hardcoded buffer length limit for now, for IRQ-fed events:
+ */
+#define PERF_DATA_BUFLEN	2048
+
+/**
+ * struct perf_data - performance counter IRQ data sampling ...
+ */
+struct perf_data {
+	int			len;
+	int			rd_idx;
+	int			overrun;
+	u8			data[PERF_DATA_BUFLEN];
+};
+
+/**
+ * struct perf_counter - performance counter kernel representation:
+ */
+struct perf_counter {
+	struct list_head		list;
+	int				active;
+#if BITS_PER_LONG == 64
+	atomic64_t			count;
+#else
+	atomic_t			count32[2];
+#endif
+	u64				__irq_period;
+
+	struct hw_perf_counter		hw;
+
+	struct perf_counter_context	*ctx;
+	struct task_struct		*task;
+
+	/*
+	 * Protect attach/detach:
+	 */
+	struct mutex			mutex;
+
+	int				oncpu;
+	int				cpu;
+
+	s32				hw_event_type;
+	enum perf_record_type		record_type;
+
+	/* read() / irq related data */
+	wait_queue_head_t		waitq;
+	/* optional: for NMIs */
+	int				wakeup_pending;
+	struct perf_data		*irqdata;
+	struct perf_data		*usrdata;
+	struct perf_data		data[2];
+};
+
+/**
+ * struct perf_counter_context - counter context structure
+ *
+ * Used as a container for task counters and CPU counters as well:
+ */
+struct perf_counter_context {
+#ifdef CONFIG_PERF_COUNTERS
+	/*
+	 * Protect the list of counters:
+	 */
+	spinlock_t		lock;
+	struct list_head	counters;
+	int			nr_counters;
+	int			nr_active;
+	struct task_struct	*task;
+#endif
+};
+
+/**
+ * struct perf_counter_cpu_context - per cpu counter context structure
+ */
+struct perf_cpu_context {
+	struct perf_counter_context	ctx;
+	struct perf_counter_context	*task_ctx;
+	int				active_oncpu;
+	int				max_pertask;
+};
+
+/*
+ * Set by architecture code:
+ */
+extern int perf_max_counters;
+
+#ifdef CONFIG_PERF_COUNTERS
+extern void perf_counter_task_sched_in(struct task_struct *task, int cpu);
+extern void perf_counter_task_sched_out(struct task_struct *task, int cpu);
+extern void perf_counter_task_tick(struct task_struct *task, int cpu);
+extern void perf_counter_init_task(struct task_struct *task);
+extern void perf_counter_notify(struct pt_regs *regs);
+extern void perf_counter_print_debug(void);
+#else
+static inline void
+perf_counter_task_sched_in(struct task_struct *task, int cpu)		{ }
+static inline void
+perf_counter_task_sched_out(struct task_struct *task, int cpu)		{ }
+static inline void
+perf_counter_task_tick(struct task_struct *task, int cpu)		{ }
+static inline void perf_counter_init_task(struct task_struct *task)	{ }
+static inline void perf_counter_notify(struct pt_regs *regs)		{ }
+static inline void perf_counter_print_debug(void)			{ }
+#endif
+
+#endif /* _LINUX_PERF_COUNTER_H */