#ifndef __LINUX_CPUMASK_H
  #define __LINUX_CPUMASK_H
  
  /*
   * Cpumasks provide a bitmap suitable for representing the
   * set of CPU's in a system, one bit position per CPU number.  In general,
   * only nr_cpu_ids (<= NR_CPUS) bits are valid.
   */
  #include <linux/kernel.h>
  #include <linux/threads.h>
  #include <linux/bitmap.h>
  #include <linux/bug.h>
  
  typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
  
  /**
   * cpumask_bits - get the bits in a cpumask
   * @maskp: the struct cpumask *
   *
   * You should only assume nr_cpu_ids bits of this mask are valid.  This is
   * a macro so it's const-correct.
   */
  #define cpumask_bits(maskp) ((maskp)->bits)
  
  #if NR_CPUS == 1
  #define nr_cpu_ids		1
  #else
  extern int nr_cpu_ids;
  #endif
  
  #ifdef CONFIG_CPUMASK_OFFSTACK
  /* Assuming NR_CPUS is huge, a runtime limit is more efficient.  Also,
   * not all bits may be allocated. */
  #define nr_cpumask_bits	nr_cpu_ids
  #else
  #define nr_cpumask_bits	NR_CPUS
  #endif
  
  /*
   * The following particular system cpumasks and operations manage
   * possible, present, active and online cpus.
   *
   *     cpu_possible_mask- has bit 'cpu' set iff cpu is populatable
   *     cpu_present_mask - has bit 'cpu' set iff cpu is populated
   *     cpu_online_mask  - has bit 'cpu' set iff cpu available to scheduler
   *     cpu_active_mask  - has bit 'cpu' set iff cpu available to migration
   *
   *  If !CONFIG_HOTPLUG_CPU, present == possible, and active == online.
   *
   *  The cpu_possible_mask is fixed at boot time, as the set of CPU id's
   *  that it is possible might ever be plugged in at anytime during the
   *  life of that system boot.  The cpu_present_mask is dynamic(*),
   *  representing which CPUs are currently plugged in.  And
   *  cpu_online_mask is the dynamic subset of cpu_present_mask,
   *  indicating those CPUs available for scheduling.
   *
   *  If HOTPLUG is enabled, then cpu_possible_mask is forced to have
   *  all NR_CPUS bits set, otherwise it is just the set of CPUs that
   *  ACPI reports present at boot.
   *
   *  If HOTPLUG is enabled, then cpu_present_mask varies dynamically,
   *  depending on what ACPI reports as currently plugged in, otherwise
   *  cpu_present_mask is just a copy of cpu_possible_mask.
   *
   *  (*) Well, cpu_present_mask is dynamic in the hotplug case.  If not
   *      hotplug, it's a copy of cpu_possible_mask, hence fixed at boot.
   *
   * Subtleties:
   * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode
   *    assumption that their single CPU is online.  The UP
   *    cpu_{online,possible,present}_masks are placebos.  Changing them
   *    will have no useful affect on the following num_*_cpus()
   *    and cpu_*() macros in the UP case.  This ugliness is a UP
   *    optimization - don't waste any instructions or memory references
   *    asking if you're online or how many CPUs there are if there is
   *    only one CPU.
   */
  
  extern const struct cpumask *const cpu_possible_mask;
  extern const struct cpumask *const cpu_online_mask;
  extern const struct cpumask *const cpu_present_mask;
  extern const struct cpumask *const cpu_active_mask;
  
  #if NR_CPUS > 1
  #define num_online_cpus()	cpumask_weight(cpu_online_mask)
  #define num_possible_cpus()	cpumask_weight(cpu_possible_mask)
  #define num_present_cpus()	cpumask_weight(cpu_present_mask)
  #define num_active_cpus()	cpumask_weight(cpu_active_mask)
  #define cpu_online(cpu)		cpumask_test_cpu((cpu), cpu_online_mask)
  #define cpu_possible(cpu)	cpumask_test_cpu((cpu), cpu_possible_mask)
  #define cpu_present(cpu)	cpumask_test_cpu((cpu), cpu_present_mask)
  #define cpu_active(cpu)		cpumask_test_cpu((cpu), cpu_active_mask)
  #else
  #define num_online_cpus()	1U
  #define num_possible_cpus()	1U
  #define num_present_cpus()	1U
  #define num_active_cpus()	1U
  #define cpu_online(cpu)		((cpu) == 0)
  #define cpu_possible(cpu)	((cpu) == 0)
  #define cpu_present(cpu)	((cpu) == 0)
  #define cpu_active(cpu)		((cpu) == 0)
  #endif
  
  /* verify cpu argument to cpumask_* operators */
  static inline unsigned int cpumask_check(unsigned int cpu)
  {
  #ifdef CONFIG_DEBUG_PER_CPU_MAPS
  	WARN_ON_ONCE(cpu >= nr_cpumask_bits);
  #endif /* CONFIG_DEBUG_PER_CPU_MAPS */
  	return cpu;
  }
  
  #if NR_CPUS == 1
  /* Uniprocessor.  Assume all masks are "1". */
  static inline unsigned int cpumask_first(const struct cpumask *srcp)
  {
  	return 0;
  }
  
  /* Valid inputs for n are -1 and 0. */
  static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
  {
  	return n+1;
  }
  
  static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
  {
  	return n+1;
  }
  
  static inline unsigned int cpumask_next_and(int n,
  					    const struct cpumask *srcp,
  					    const struct cpumask *andp)
  {
  	return n+1;
  }
  
  /* cpu must be a valid cpu, ie 0, so there's no other choice. */
  static inline unsigned int cpumask_any_but(const struct cpumask *mask,
  					   unsigned int cpu)
  {
  	return 1;
  }
  
  #define for_each_cpu(cpu, mask)			\
  	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
  #define for_each_cpu_not(cpu, mask)		\
  	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
  #define for_each_cpu_and(cpu, mask, and)	\
  	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask, (void)and)
  #else
  /**
   * cpumask_first - get the first cpu in a cpumask
   * @srcp: the cpumask pointer
   *
   * Returns >= nr_cpu_ids if no cpus set.
   */
  static inline unsigned int cpumask_first(const struct cpumask *srcp)
  {
  	return find_first_bit(cpumask_bits(srcp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_next - get the next cpu in a cpumask
   * @n: the cpu prior to the place to search (ie. return will be > @n)
   * @srcp: the cpumask pointer
   *
   * Returns >= nr_cpu_ids if no further cpus set.
   */
  static inline unsigned int cpumask_next(int n, const struct cpumask *srcp)
  {
  	/* -1 is a legal arg here. */
  	if (n != -1)
  		cpumask_check(n);
  	return find_next_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
  }
  
  /**
   * cpumask_next_zero - get the next unset cpu in a cpumask
   * @n: the cpu prior to the place to search (ie. return will be > @n)
   * @srcp: the cpumask pointer
   *
   * Returns >= nr_cpu_ids if no further cpus unset.
   */
  static inline unsigned int cpumask_next_zero(int n, const struct cpumask *srcp)
  {
  	/* -1 is a legal arg here. */
  	if (n != -1)
  		cpumask_check(n);
  	return find_next_zero_bit(cpumask_bits(srcp), nr_cpumask_bits, n+1);
  }
  
  int cpumask_next_and(int n, const struct cpumask *, const struct cpumask *);
  int cpumask_any_but(const struct cpumask *mask, unsigned int cpu);
  
  /**
   * for_each_cpu - iterate over every cpu in a mask
   * @cpu: the (optionally unsigned) integer iterator
   * @mask: the cpumask pointer
   *
   * After the loop, cpu is >= nr_cpu_ids.
   */
  #define for_each_cpu(cpu, mask)				\
  	for ((cpu) = -1;				\
  		(cpu) = cpumask_next((cpu), (mask)),	\
  		(cpu) < nr_cpu_ids;)
  
  /**
   * for_each_cpu_not - iterate over every cpu in a complemented mask
   * @cpu: the (optionally unsigned) integer iterator
   * @mask: the cpumask pointer
   *
   * After the loop, cpu is >= nr_cpu_ids.
   */
  #define for_each_cpu_not(cpu, mask)				\
  	for ((cpu) = -1;					\
  		(cpu) = cpumask_next_zero((cpu), (mask)),	\
  		(cpu) < nr_cpu_ids;)
  
  /**
   * for_each_cpu_and - iterate over every cpu in both masks
   * @cpu: the (optionally unsigned) integer iterator
   * @mask: the first cpumask pointer
   * @and: the second cpumask pointer
   *
   * This saves a temporary CPU mask in many places.  It is equivalent to:
   *	struct cpumask tmp;
   *	cpumask_and(&tmp, &mask, &and);
   *	for_each_cpu(cpu, &tmp)
   *		...
   *
   * After the loop, cpu is >= nr_cpu_ids.
   */
  #define for_each_cpu_and(cpu, mask, and)				\
  	for ((cpu) = -1;						\
  		(cpu) = cpumask_next_and((cpu), (mask), (and)),		\
  		(cpu) < nr_cpu_ids;)
  #endif /* SMP */
  
  #define CPU_BITS_NONE						\
  {								\
  	[0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL			\
  }
  
  #define CPU_BITS_CPU0						\
  {								\
  	[0] =  1UL						\
  }
  
  /**
   * cpumask_set_cpu - set a cpu in a cpumask
   * @cpu: cpu number (< nr_cpu_ids)
   * @dstp: the cpumask pointer
   */
  static inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp)
  {
  	set_bit(cpumask_check(cpu), cpumask_bits(dstp));
  }
  
  /**
   * cpumask_clear_cpu - clear a cpu in a cpumask
   * @cpu: cpu number (< nr_cpu_ids)
   * @dstp: the cpumask pointer
   */
  static inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp)
  {
  	clear_bit(cpumask_check(cpu), cpumask_bits(dstp));
  }
  
  /**
   * cpumask_test_cpu - test for a cpu in a cpumask
   * @cpu: cpu number (< nr_cpu_ids)
   * @cpumask: the cpumask pointer
   *
   * Returns 1 if @cpu is set in @cpumask, else returns 0
   *
   * No static inline type checking - see Subtlety (1) above.
   */
  #define cpumask_test_cpu(cpu, cpumask) \
  	test_bit(cpumask_check(cpu), cpumask_bits((cpumask)))
  
  /**
   * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
   * @cpu: cpu number (< nr_cpu_ids)
   * @cpumask: the cpumask pointer
   *
   * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
   *
   * test_and_set_bit wrapper for cpumasks.
   */
  static inline int cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask)
  {
  	return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask));
  }
  
  /**
   * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask
   * @cpu: cpu number (< nr_cpu_ids)
   * @cpumask: the cpumask pointer
   *
   * Returns 1 if @cpu is set in old bitmap of @cpumask, else returns 0
   *
   * test_and_clear_bit wrapper for cpumasks.
   */
  static inline int cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask)
  {
  	return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask));
  }
  
  /**
   * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask
   * @dstp: the cpumask pointer
   */
  static inline void cpumask_setall(struct cpumask *dstp)
  {
  	bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask
   * @dstp: the cpumask pointer
   */
  static inline void cpumask_clear(struct cpumask *dstp)
  {
  	bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_and - *dstp = *src1p & *src2p
   * @dstp: the cpumask result
   * @src1p: the first input
   * @src2p: the second input
   *
   * If *@dstp is empty, returns 0, else returns 1
   */
  static inline int cpumask_and(struct cpumask *dstp,
  			       const struct cpumask *src1p,
  			       const struct cpumask *src2p)
  {
  	return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p),
  				       cpumask_bits(src2p), nr_cpumask_bits);
  }
  
  /**
   * cpumask_or - *dstp = *src1p | *src2p
   * @dstp: the cpumask result
   * @src1p: the first input
   * @src2p: the second input
   */
  static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p,
  			      const struct cpumask *src2p)
  {
  	bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p),
  				      cpumask_bits(src2p), nr_cpumask_bits);
  }
  
  /**
   * cpumask_xor - *dstp = *src1p ^ *src2p
   * @dstp: the cpumask result
   * @src1p: the first input
   * @src2p: the second input
   */
  static inline void cpumask_xor(struct cpumask *dstp,
  			       const struct cpumask *src1p,
  			       const struct cpumask *src2p)
  {
  	bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p),
  				       cpumask_bits(src2p), nr_cpumask_bits);
  }
  
  /**
   * cpumask_andnot - *dstp = *src1p & ~*src2p
   * @dstp: the cpumask result
   * @src1p: the first input
   * @src2p: the second input
   *
   * If *@dstp is empty, returns 0, else returns 1
   */
  static inline int cpumask_andnot(struct cpumask *dstp,
  				  const struct cpumask *src1p,
  				  const struct cpumask *src2p)
  {
  	return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p),
  					  cpumask_bits(src2p), nr_cpumask_bits);
  }
  
  /**
   * cpumask_complement - *dstp = ~*srcp
   * @dstp: the cpumask result
   * @srcp: the input to invert
   */
  static inline void cpumask_complement(struct cpumask *dstp,
  				      const struct cpumask *srcp)
  {
  	bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp),
  					      nr_cpumask_bits);
  }
  
  /**
   * cpumask_equal - *src1p == *src2p
   * @src1p: the first input
   * @src2p: the second input
   */
  static inline bool cpumask_equal(const struct cpumask *src1p,
  				const struct cpumask *src2p)
  {
  	return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p),
  						 nr_cpumask_bits);
  }
  
  /**
   * cpumask_intersects - (*src1p & *src2p) != 0
   * @src1p: the first input
   * @src2p: the second input
   */
  static inline bool cpumask_intersects(const struct cpumask *src1p,
  				     const struct cpumask *src2p)
  {
  	return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p),
  						      nr_cpumask_bits);
  }
  
  /**
   * cpumask_subset - (*src1p & ~*src2p) == 0
   * @src1p: the first input
   * @src2p: the second input
   *
   * Returns 1 if *@src1p is a subset of *@src2p, else returns 0
   */
  static inline int cpumask_subset(const struct cpumask *src1p,
  				 const struct cpumask *src2p)
  {
  	return bitmap_subset(cpumask_bits(src1p), cpumask_bits(src2p),
  						  nr_cpumask_bits);
  }
  
  /**
   * cpumask_empty - *srcp == 0
   * @srcp: the cpumask to that all cpus < nr_cpu_ids are clear.
   */
  static inline bool cpumask_empty(const struct cpumask *srcp)
  {
  	return bitmap_empty(cpumask_bits(srcp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_full - *srcp == 0xFFFFFFFF...
   * @srcp: the cpumask to that all cpus < nr_cpu_ids are set.
   */
  static inline bool cpumask_full(const struct cpumask *srcp)
  {
  	return bitmap_full(cpumask_bits(srcp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_weight - Count of bits in *srcp
   * @srcp: the cpumask to count bits (< nr_cpu_ids) in.
   */
  static inline unsigned int cpumask_weight(const struct cpumask *srcp)
  {
  	return bitmap_weight(cpumask_bits(srcp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_shift_right - *dstp = *srcp >> n
   * @dstp: the cpumask result
   * @srcp: the input to shift
   * @n: the number of bits to shift by
   */
  static inline void cpumask_shift_right(struct cpumask *dstp,
  				       const struct cpumask *srcp, int n)
  {
  	bitmap_shift_right(cpumask_bits(dstp), cpumask_bits(srcp), n,
  					       nr_cpumask_bits);
  }
  
  /**
   * cpumask_shift_left - *dstp = *srcp << n
   * @dstp: the cpumask result
   * @srcp: the input to shift
   * @n: the number of bits to shift by
   */
  static inline void cpumask_shift_left(struct cpumask *dstp,
  				      const struct cpumask *srcp, int n)
  {
  	bitmap_shift_left(cpumask_bits(dstp), cpumask_bits(srcp), n,
  					      nr_cpumask_bits);
  }
  
  /**
   * cpumask_copy - *dstp = *srcp
   * @dstp: the result
   * @srcp: the input cpumask
   */
  static inline void cpumask_copy(struct cpumask *dstp,
  				const struct cpumask *srcp)
  {
  	bitmap_copy(cpumask_bits(dstp), cpumask_bits(srcp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_any - pick a "random" cpu from *srcp
   * @srcp: the input cpumask
   *
   * Returns >= nr_cpu_ids if no cpus set.
   */
  #define cpumask_any(srcp) cpumask_first(srcp)
  
  /**
   * cpumask_first_and - return the first cpu from *srcp1 & *srcp2
   * @src1p: the first input
   * @src2p: the second input
   *
   * Returns >= nr_cpu_ids if no cpus set in both.  See also cpumask_next_and().
   */
  #define cpumask_first_and(src1p, src2p) cpumask_next_and(-1, (src1p), (src2p))
  
  /**
   * cpumask_any_and - pick a "random" cpu from *mask1 & *mask2
   * @mask1: the first input cpumask
   * @mask2: the second input cpumask
   *
   * Returns >= nr_cpu_ids if no cpus set.
   */
  #define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2))
  
  /**
   * cpumask_of - the cpumask containing just a given cpu
   * @cpu: the cpu (<= nr_cpu_ids)
   */
  #define cpumask_of(cpu) (get_cpu_mask(cpu))
  
  /**
   * cpumask_scnprintf - print a cpumask into a string as comma-separated hex
   * @buf: the buffer to sprintf into
   * @len: the length of the buffer
   * @srcp: the cpumask to print
   *
   * If len is zero, returns zero.  Otherwise returns the length of the
   * (nul-terminated) @buf string.
   */
  static inline int cpumask_scnprintf(char *buf, int len,
  				    const struct cpumask *srcp)
  {
  	return bitmap_scnprintf(buf, len, cpumask_bits(srcp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_parse_user - extract a cpumask from a user string
   * @buf: the buffer to extract from
   * @len: the length of the buffer
   * @dstp: the cpumask to set.
   *
   * Returns -errno, or 0 for success.
   */
  static inline int cpumask_parse_user(const char __user *buf, int len,
  				     struct cpumask *dstp)
  {
  	return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_parselist_user - extract a cpumask from a user string
   * @buf: the buffer to extract from
   * @len: the length of the buffer
   * @dstp: the cpumask to set.
   *
   * Returns -errno, or 0 for success.
   */
  static inline int cpumask_parselist_user(const char __user *buf, int len,
  				     struct cpumask *dstp)
  {
  	return bitmap_parselist_user(buf, len, cpumask_bits(dstp),
  							nr_cpumask_bits);
  }
  
  /**
   * cpulist_scnprintf - print a cpumask into a string as comma-separated list
   * @buf: the buffer to sprintf into
   * @len: the length of the buffer
   * @srcp: the cpumask to print
   *
   * If len is zero, returns zero.  Otherwise returns the length of the
   * (nul-terminated) @buf string.
   */
  static inline int cpulist_scnprintf(char *buf, int len,
  				    const struct cpumask *srcp)
  {
  	return bitmap_scnlistprintf(buf, len, cpumask_bits(srcp),
  				    nr_cpumask_bits);
  }
  
  /**
   * cpumask_parse - extract a cpumask from from a string
   * @buf: the buffer to extract from
   * @dstp: the cpumask to set.
   *
   * Returns -errno, or 0 for success.
   */
  static inline int cpumask_parse(const char *buf, struct cpumask *dstp)
  {
  	char *nl = strchr(buf, '
  ');
  	int len = nl ? nl - buf : strlen(buf);
  
  	return bitmap_parse(buf, len, cpumask_bits(dstp), nr_cpumask_bits);
  }
  
  /**
   * cpulist_parse - extract a cpumask from a user string of ranges
   * @buf: the buffer to extract from
   * @dstp: the cpumask to set.
   *
   * Returns -errno, or 0 for success.
   */
  static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
  {
  	return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits);
  }
  
  /**
   * cpumask_size - size to allocate for a 'struct cpumask' in bytes
   *
   * This will eventually be a runtime variable, depending on nr_cpu_ids.
   */
  static inline size_t cpumask_size(void)
  {
  	/* FIXME: Once all cpumask assignments are eliminated, this
  	 * can be nr_cpumask_bits */
  	return BITS_TO_LONGS(NR_CPUS) * sizeof(long);
  }
  
  /*
   * cpumask_var_t: struct cpumask for stack usage.
   *
   * Oh, the wicked games we play!  In order to make kernel coding a
   * little more difficult, we typedef cpumask_var_t to an array or a
   * pointer: doing &mask on an array is a noop, so it still works.
   *
   * ie.
   *	cpumask_var_t tmpmask;
   *	if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
   *		return -ENOMEM;
   *
   *	  ... use 'tmpmask' like a normal struct cpumask * ...
   *
   *	free_cpumask_var(tmpmask);
   *
   *
   * However, one notable exception is there. alloc_cpumask_var() allocates
   * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has
   * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t.
   *
   *	cpumask_var_t tmpmask;
   *	if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL))
   *		return -ENOMEM;
   *
   *	var = *tmpmask;
   *
   * This code makes NR_CPUS length memcopy and brings to a memory corruption.
   * cpumask_copy() provide safe copy functionality.
   */
  #ifdef CONFIG_CPUMASK_OFFSTACK
  typedef struct cpumask *cpumask_var_t;
  
  bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
  bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
  bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node);
  bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags);
  void alloc_bootmem_cpumask_var(cpumask_var_t *mask);
  void free_cpumask_var(cpumask_var_t mask);
  void free_bootmem_cpumask_var(cpumask_var_t mask);
  
  #else
  typedef struct cpumask cpumask_var_t[1];
  
  static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
  {
  	return true;
  }
  
  static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
  					  int node)
  {
  	return true;
  }
  
  static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags)
  {
  	cpumask_clear(*mask);
  	return true;
  }
  
  static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags,
  					  int node)
  {
  	cpumask_clear(*mask);
  	return true;
  }
  
  static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask)
  {
  }
  
  static inline void free_cpumask_var(cpumask_var_t mask)
  {
  }
  
  static inline void free_bootmem_cpumask_var(cpumask_var_t mask)
  {
  }
  #endif /* CONFIG_CPUMASK_OFFSTACK */
  
  /* It's common to want to use cpu_all_mask in struct member initializers,
   * so it has to refer to an address rather than a pointer. */
  extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS);
  #define cpu_all_mask to_cpumask(cpu_all_bits)
  
  /* First bits of cpu_bit_bitmap are in fact unset. */
  #define cpu_none_mask to_cpumask(cpu_bit_bitmap[0])
  
  #define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask)
  #define for_each_online_cpu(cpu)   for_each_cpu((cpu), cpu_online_mask)
  #define for_each_present_cpu(cpu)  for_each_cpu((cpu), cpu_present_mask)
  
  /* Wrappers for arch boot code to manipulate normally-constant masks */
  void set_cpu_possible(unsigned int cpu, bool possible);
  void set_cpu_present(unsigned int cpu, bool present);
  void set_cpu_online(unsigned int cpu, bool online);
  void set_cpu_active(unsigned int cpu, bool active);
  void init_cpu_present(const struct cpumask *src);
  void init_cpu_possible(const struct cpumask *src);
  void init_cpu_online(const struct cpumask *src);
  
  /**
   * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask *
   * @bitmap: the bitmap
   *
   * There are a few places where cpumask_var_t isn't appropriate and
   * static cpumasks must be used (eg. very early boot), yet we don't
   * expose the definition of 'struct cpumask'.
   *
   * This does the conversion, and can be used as a constant initializer.
   */
  #define to_cpumask(bitmap)						\
  	((struct cpumask *)(1 ? (bitmap)				\
  			    : (void *)sizeof(__check_is_bitmap(bitmap))))
  
  static inline int __check_is_bitmap(const unsigned long *bitmap)
  {
  	return 1;
  }
  
  /*
   * Special-case data structure for "single bit set only" constant CPU masks.
   *
   * We pre-generate all the 64 (or 32) possible bit positions, with enough
   * padding to the left and the right, and return the constant pointer
   * appropriately offset.
   */
  extern const unsigned long
  	cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)];
  
  static inline const struct cpumask *get_cpu_mask(unsigned int cpu)
  {
  	const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
  	p -= cpu / BITS_PER_LONG;
  	return to_cpumask(p);
  }
  
  #define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))
  
  #if NR_CPUS <= BITS_PER_LONG
  #define CPU_BITS_ALL						\
  {								\
  	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD	\
  }
  
  #else /* NR_CPUS > BITS_PER_LONG */
  
  #define CPU_BITS_ALL						\
  {								\
  	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,		\
  	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD		\
  }
  #endif /* NR_CPUS > BITS_PER_LONG */
  
  /*
   *
   * From here down, all obsolete.  Use cpumask_ variants!
   *
   */
  #ifndef CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
  #define cpumask_of_cpu(cpu) (*get_cpu_mask(cpu))
  
  #define CPU_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(NR_CPUS)
  
  #if NR_CPUS <= BITS_PER_LONG
  
  #define CPU_MASK_ALL							\
  (cpumask_t) { {								\
  	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD			\
  } }
  
  #else
  
  #define CPU_MASK_ALL							\
  (cpumask_t) { {								\
  	[0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL,			\
  	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD			\
  } }
  
  #endif
  
  #define CPU_MASK_NONE							\
  (cpumask_t) { {								\
  	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  0UL				\
  } }
  
  #define CPU_MASK_CPU0							\
  (cpumask_t) { {								\
  	[0] =  1UL							\
  } }
  
  #if NR_CPUS == 1
  #define first_cpu(src)		({ (void)(src); 0; })
  #define next_cpu(n, src)	({ (void)(src); 1; })
  #define any_online_cpu(mask)	0
  #define for_each_cpu_mask(cpu, mask)	\
  	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
  #else /* NR_CPUS > 1 */
  int __first_cpu(const cpumask_t *srcp);
  int __next_cpu(int n, const cpumask_t *srcp);
  
  #define first_cpu(src)		__first_cpu(&(src))
  #define next_cpu(n, src)	__next_cpu((n), &(src))
  #define any_online_cpu(mask) cpumask_any_and(&mask, cpu_online_mask)
  #define for_each_cpu_mask(cpu, mask)			\
  	for ((cpu) = -1;				\
  		(cpu) = next_cpu((cpu), (mask)),	\
  		(cpu) < NR_CPUS; )
  #endif /* SMP */
  
  #if NR_CPUS <= 64
  
  #define for_each_cpu_mask_nr(cpu, mask)	for_each_cpu_mask(cpu, mask)
  
  #else /* NR_CPUS > 64 */
  
  int __next_cpu_nr(int n, const cpumask_t *srcp);
  #define for_each_cpu_mask_nr(cpu, mask)			\
  	for ((cpu) = -1;				\
  		(cpu) = __next_cpu_nr((cpu), &(mask)),	\
  		(cpu) < nr_cpu_ids; )
  
  #endif /* NR_CPUS > 64 */
  
  #define cpus_addr(src) ((src).bits)
  
  #define cpu_set(cpu, dst) __cpu_set((cpu), &(dst))
  static inline void __cpu_set(int cpu, volatile cpumask_t *dstp)
  {
  	set_bit(cpu, dstp->bits);
  }
  
  #define cpu_clear(cpu, dst) __cpu_clear((cpu), &(dst))
  static inline void __cpu_clear(int cpu, volatile cpumask_t *dstp)
  {
  	clear_bit(cpu, dstp->bits);
  }
  
  #define cpus_setall(dst) __cpus_setall(&(dst), NR_CPUS)
  static inline void __cpus_setall(cpumask_t *dstp, int nbits)
  {
  	bitmap_fill(dstp->bits, nbits);
  }
  
  #define cpus_clear(dst) __cpus_clear(&(dst), NR_CPUS)
  static inline void __cpus_clear(cpumask_t *dstp, int nbits)
  {
  	bitmap_zero(dstp->bits, nbits);
  }
  
  /* No static inline type checking - see Subtlety (1) above. */
  #define cpu_isset(cpu, cpumask) test_bit((cpu), (cpumask).bits)
  
  #define cpu_test_and_set(cpu, cpumask) __cpu_test_and_set((cpu), &(cpumask))
  static inline int __cpu_test_and_set(int cpu, cpumask_t *addr)
  {
  	return test_and_set_bit(cpu, addr->bits);
  }
  
  #define cpus_and(dst, src1, src2) __cpus_and(&(dst), &(src1), &(src2), NR_CPUS)
  static inline int __cpus_and(cpumask_t *dstp, const cpumask_t *src1p,
  					const cpumask_t *src2p, int nbits)
  {
  	return bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
  }
  
  #define cpus_or(dst, src1, src2) __cpus_or(&(dst), &(src1), &(src2), NR_CPUS)
  static inline void __cpus_or(cpumask_t *dstp, const cpumask_t *src1p,
  					const cpumask_t *src2p, int nbits)
  {
  	bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits);
  }
  
  #define cpus_xor(dst, src1, src2) __cpus_xor(&(dst), &(src1), &(src2), NR_CPUS)
  static inline void __cpus_xor(cpumask_t *dstp, const cpumask_t *src1p,
  					const cpumask_t *src2p, int nbits)
  {
  	bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits);
  }
  
  #define cpus_andnot(dst, src1, src2) \
  				__cpus_andnot(&(dst), &(src1), &(src2), NR_CPUS)
  static inline int __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p,
  					const cpumask_t *src2p, int nbits)
  {
  	return bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
  }
  
  #define cpus_equal(src1, src2) __cpus_equal(&(src1), &(src2), NR_CPUS)
  static inline int __cpus_equal(const cpumask_t *src1p,
  					const cpumask_t *src2p, int nbits)
  {
  	return bitmap_equal(src1p->bits, src2p->bits, nbits);
  }
  
  #define cpus_intersects(src1, src2) __cpus_intersects(&(src1), &(src2), NR_CPUS)
  static inline int __cpus_intersects(const cpumask_t *src1p,
  					const cpumask_t *src2p, int nbits)
  {
  	return bitmap_intersects(src1p->bits, src2p->bits, nbits);
  }
  
  #define cpus_subset(src1, src2) __cpus_subset(&(src1), &(src2), NR_CPUS)
  static inline int __cpus_subset(const cpumask_t *src1p,
  					const cpumask_t *src2p, int nbits)
  {
  	return bitmap_subset(src1p->bits, src2p->bits, nbits);
  }
  
  #define cpus_empty(src) __cpus_empty(&(src), NR_CPUS)
  static inline int __cpus_empty(const cpumask_t *srcp, int nbits)
  {
  	return bitmap_empty(srcp->bits, nbits);
  }
  
  #define cpus_weight(cpumask) __cpus_weight(&(cpumask), NR_CPUS)
  static inline int __cpus_weight(const cpumask_t *srcp, int nbits)
  {
  	return bitmap_weight(srcp->bits, nbits);
  }
  
  #define cpus_shift_left(dst, src, n) \
  			__cpus_shift_left(&(dst), &(src), (n), NR_CPUS)
  static inline void __cpus_shift_left(cpumask_t *dstp,
  					const cpumask_t *srcp, int n, int nbits)
  {
  	bitmap_shift_left(dstp->bits, srcp->bits, n, nbits);
  }
  #endif /* !CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS */
  
  #endif /* __LINUX_CPUMASK_H */