#ifndef _PERF_PERF_H
  #define _PERF_PERF_H

  struct winsize;
  
  void get_term_dimensions(struct winsize *ws);

  #if defined(__i386__)
  #include "../../arch/x86/include/asm/unistd.h"
  #define rmb()		asm volatile("lock; addl $0,0(%%esp)" ::: "memory")
  #define cpu_relax()	asm volatile("rep; nop" ::: "memory");
  #endif
  
  #if defined(__x86_64__)

  #include "../../arch/x86/include/asm/unistd.h"
  #define rmb()		asm volatile("lfence" ::: "memory")
  #define cpu_relax()	asm volatile("rep; nop" ::: "memory");
  #endif
  
  #ifdef __powerpc__
  #include "../../arch/powerpc/include/asm/unistd.h"
  #define rmb()		asm volatile ("sync" ::: "memory")
  #define cpu_relax()	asm volatile ("" ::: "memory");
  #endif

  #ifdef __s390__
  #include "../../arch/s390/include/asm/unistd.h"
  #define rmb()		asm volatile("bcr 15,0" ::: "memory")
  #define cpu_relax()	asm volatile("" ::: "memory");
  #endif

  #ifdef __sh__
  #include "../../arch/sh/include/asm/unistd.h"
  #if defined(__SH4A__) || defined(__SH5__)
  # define rmb()		asm volatile("synco" ::: "memory")
  #else
  # define rmb()		asm volatile("" ::: "memory")
  #endif
  #define cpu_relax()	asm volatile("" ::: "memory")
  #endif

  #ifdef __hppa__
  #include "../../arch/parisc/include/asm/unistd.h"
  #define rmb()		asm volatile("" ::: "memory")
  #define cpu_relax()	asm volatile("" ::: "memory");
  #endif

  #ifdef __sparc__
  #include "../../arch/sparc/include/asm/unistd.h"
  #define rmb()		asm volatile("":::"memory")
  #define cpu_relax()	asm volatile("":::"memory")
  #endif

  #ifdef __alpha__
  #include "../../arch/alpha/include/asm/unistd.h"
  #define rmb()		asm volatile("mb" ::: "memory")
  #define cpu_relax()	asm volatile("" ::: "memory")
  #endif

  #ifdef __ia64__
  #include "../../arch/ia64/include/asm/unistd.h"
  #define rmb()		asm volatile ("mf" ::: "memory")
  #define cpu_relax()	asm volatile ("hint @pause" ::: "memory")
  #endif

  #ifdef __arm__
  #include "../../arch/arm/include/asm/unistd.h"
  /*
   * Use the __kuser_memory_barrier helper in the CPU helper page. See
   * arch/arm/kernel/entry-armv.S in the kernel source for details.
   */

  #define rmb()		((void(*)(void))0xffff0fa0)()

  #define cpu_relax()	asm volatile("":::"memory")
  #endif

  #ifdef __mips__
  #include "../../arch/mips/include/asm/unistd.h"
  #define rmb()		asm volatile(					\
  				".set	mips2
  \t"			\
  				"sync
  \t"				\
  				".set	mips0"				\
  				: /* no output */			\
  				: /* no input */			\
  				: "memory")
  #define cpu_relax()	asm volatile("" ::: "memory")
  #endif

  #include <time.h>
  #include <unistd.h>
  #include <sys/types.h>
  #include <sys/syscall.h>

  #include "../../include/linux/perf_event.h"

  #include "util/types.h"

  #include <stdbool.h>

  struct perf_mmap {
  	void			*base;
  	int			mask;
  	unsigned int		prev;
  };
  
  static inline unsigned int perf_mmap__read_head(struct perf_mmap *mm)
  {
  	struct perf_event_mmap_page *pc = mm->base;
  	int head = pc->data_head;
  	rmb();
  	return head;
  }

  static inline void perf_mmap__write_tail(struct perf_mmap *md,
  					 unsigned long tail)
  {
  	struct perf_event_mmap_page *pc = md->base;
  
  	/*
  	 * ensure all reads are done before we write the tail out.
  	 */
  	/* mb(); */
  	pc->data_tail = tail;
  }

  /*

   * prctl(PR_TASK_PERF_EVENTS_DISABLE) will (cheaply) disable all

   * counters in the current task.
   */

  #define PR_TASK_PERF_EVENTS_DISABLE   31
  #define PR_TASK_PERF_EVENTS_ENABLE    32

  #ifndef NSEC_PER_SEC
  # define NSEC_PER_SEC			1000000000ULL
  #endif
  
  static inline unsigned long long rdclock(void)
  {
  	struct timespec ts;
  
  	clock_gettime(CLOCK_MONOTONIC, &ts);
  	return ts.tv_sec * 1000000000ULL + ts.tv_nsec;
  }

  
  /*
   * Pick up some kernel type conventions:
   */
  #define __user
  #define asmlinkage

  #define unlikely(x)	__builtin_expect(!!(x), 0)
  #define min(x, y) ({				\
  	typeof(x) _min1 = (x);			\
  	typeof(y) _min2 = (y);			\
  	(void) (&_min1 == &_min2);		\
  	_min1 < _min2 ? _min1 : _min2; })
  
  static inline int

  sys_perf_event_open(struct perf_event_attr *attr,

  		      pid_t pid, int cpu, int group_fd,
  		      unsigned long flags)
  {

  	attr->size = sizeof(*attr);

  	return syscall(__NR_perf_event_open, attr, pid, cpu,

  		       group_fd, flags);
  }

  #define MAX_COUNTERS			256
  #define MAX_NR_CPUS			256

  struct ip_callchain {
  	u64 nr;
  	u64 ips[0];

  };

  extern bool perf_host, perf_guest;

  #endif