include/linux/cpumask.h - arm/linux-arm64-legacy - Git at Google

 #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.
  *
  * See detailed comments in the file linux/bitmap.h describing the
  * data type on which these cpumasks are based.
  *
  * For details of cpumask_scnprintf() and cpumask_parse_user(),
  * see bitmap_scnprintf() and bitmap_parse_user() in lib/bitmap.c.
  * For details of cpulist_scnprintf() and cpulist_parse(), see
  * bitmap_scnlistprintf() and bitmap_parselist(), also in bitmap.c.
  * For details of cpu_remap(), see bitmap_bitremap in lib/bitmap.c
  * For details of cpus_remap(), see bitmap_remap in lib/bitmap.c.
  * For details of cpus_onto(), see bitmap_onto in lib/bitmap.c.
  * For details of cpus_fold(), see bitmap_fold in lib/bitmap.c.
  *
  * The available cpumask operations are:
  *
  * void cpu_set(cpu, mask)		turn on bit 'cpu' in mask
  * void cpu_clear(cpu, mask)		turn off bit 'cpu' in mask
  * void cpus_setall(mask)		set all bits
  * void cpus_clear(mask)		clear all bits
  * int cpu_isset(cpu, mask)		true iff bit 'cpu' set in mask
  * int cpu_test_and_set(cpu, mask)	test and set bit 'cpu' in mask
  *
  * void cpus_and(dst, src1, src2)	dst = src1 & src2  [intersection]
  * void cpus_or(dst, src1, src2)	dst = src1 | src2  [union]
  * void cpus_xor(dst, src1, src2)	dst = src1 ^ src2
  * void cpus_andnot(dst, src1, src2)	dst = src1 & ~src2
  * void cpus_complement(dst, src)	dst = ~src
  *
  * int cpus_equal(mask1, mask2)		Does mask1 == mask2?
  * int cpus_intersects(mask1, mask2)	Do mask1 and mask2 intersect?
  * int cpus_subset(mask1, mask2)	Is mask1 a subset of mask2?
  * int cpus_empty(mask)			Is mask empty (no bits sets)?
  * int cpus_full(mask)			Is mask full (all bits sets)?
  * int cpus_weight(mask)		Hamming weigh - number of set bits
  *
  * void cpus_shift_right(dst, src, n)	Shift right
  * void cpus_shift_left(dst, src, n)	Shift left
  *
  * int first_cpu(mask)			Number lowest set bit, or NR_CPUS
  * int next_cpu(cpu, mask)		Next cpu past 'cpu', or NR_CPUS
  *
  * cpumask_t cpumask_of_cpu(cpu)	Return cpumask with bit 'cpu' set
  * CPU_MASK_ALL				Initializer - all bits set
  * CPU_MASK_NONE			Initializer - no bits set
  * unsigned long *cpus_addr(mask)	Array of unsigned long's in mask
  *
  * int cpumask_scnprintf(buf, len, mask) Format cpumask for printing
  * int cpumask_parse_user(ubuf, ulen, mask)	Parse ascii string as cpumask
  * int cpulist_scnprintf(buf, len, mask) Format cpumask as list for printing
  * int cpulist_parse(buf, map)		Parse ascii string as cpulist
  * int cpu_remap(oldbit, old, new)	newbit = map(old, new)(oldbit)
  * void cpus_remap(dst, src, old, new)	*dst = map(old, new)(src)
  * void cpus_onto(dst, orig, relmap)	*dst = orig relative to relmap
  * void cpus_fold(dst, orig, sz)	dst bits = orig bits mod sz
  *
  * for_each_cpu_mask(cpu, mask)		for-loop cpu over mask
  *
  * int num_online_cpus()		Number of online CPUs
  * int num_possible_cpus()		Number of all possible CPUs
  * int num_present_cpus()		Number of present CPUs
  *
  * int cpu_online(cpu)			Is some cpu online?
  * int cpu_possible(cpu)		Is some cpu possible?
  * int cpu_present(cpu)			Is some cpu present (can schedule)?
  *
  * int any_online_cpu(mask)		First online cpu in mask
  *
  * for_each_possible_cpu(cpu)		for-loop cpu over cpu_possible_map
  * for_each_online_cpu(cpu)		for-loop cpu over cpu_online_map
  * for_each_present_cpu(cpu)		for-loop cpu over cpu_present_map
  *
  * Subtlety:
  * 1) The 'type-checked' form of cpu_isset() causes gcc (3.3.2, anyway)
  *    to generate slightly worse code.  Note for example the additional
  *    40 lines of assembly code compiling the "for each possible cpu"
  *    loops buried in the disk_stat_read() macros calls when compiling
  *    drivers/block/genhd.c (arch i386, CONFIG_SMP=y).  So use a simple
  *    one-line #define for cpu_isset(), instead of wrapping an inline
  *    inside a macro, the way we do the other calls.
  */

 #include <linux/kernel.h>
 #include <linux/threads.h>
 #include <linux/bitmap.h>

 typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
 extern cpumask_t _unused_cpumask_arg_;

 #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 void __cpus_and(cpumask_t *dstp, const cpumask_t *src1p,
 					const cpumask_t *src2p, int nbits)
 {
 	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 void __cpus_andnot(cpumask_t *dstp, const cpumask_t *src1p,
 					const cpumask_t *src2p, int nbits)
 {
 	bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
 }

 #define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS)
 static inline void __cpus_complement(cpumask_t *dstp,
 					const cpumask_t *srcp, int nbits)
 {
 	bitmap_complement(dstp->bits, srcp->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_full(cpumask) __cpus_full(&(cpumask), NR_CPUS)
 static inline int __cpus_full(const cpumask_t *srcp, int nbits)
 {
 	return bitmap_full(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_right(dst, src, n) \
 			__cpus_shift_right(&(dst), &(src), (n), NR_CPUS)
 static inline void __cpus_shift_right(cpumask_t *dstp,
 					const cpumask_t *srcp, int n, int nbits)
 {
 	bitmap_shift_right(dstp->bits, srcp->bits, n, 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);
 }

 #ifdef CONFIG_SMP
 int __first_cpu(const cpumask_t *srcp);
 #define first_cpu(src) __first_cpu(&(src))
 int __next_cpu(int n, const cpumask_t *srcp);
 #define next_cpu(n, src) __next_cpu((n), &(src))
 #else
 #define first_cpu(src)		({ (void)(src); 0; })
 #define next_cpu(n, src)	({ (void)(src); 1; })
 #endif

 #ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP
 extern cpumask_t *cpumask_of_cpu_map;
 #define cpumask_of_cpu(cpu)    (cpumask_of_cpu_map[cpu])

 #else
 #define cpumask_of_cpu(cpu)						\
 (*({									\
 	typeof(_unused_cpumask_arg_) m;					\
 	if (sizeof(m) == sizeof(unsigned long)) {			\
 		m.bits[0] = 1UL<<(cpu);					\
 	} else {							\
 		cpus_clear(m);						\
 		cpu_set((cpu), m);					\
 	}								\
 	&m;								\
 }))
 #endif

 #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			\
 } }

 #define CPU_MASK_ALL_PTR	(&CPU_MASK_ALL)

 #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			\
 } }

 /* cpu_mask_all is in init/main.c */
 extern cpumask_t cpu_mask_all;
 #define CPU_MASK_ALL_PTR	(&cpu_mask_all)

 #endif

 #define CPU_MASK_NONE							\
 (cpumask_t) { {								\
 	[0 ... BITS_TO_LONGS(NR_CPUS)-1] =  0UL				\
 } }

 #define CPU_MASK_CPU0							\
 (cpumask_t) { {								\
 	[0] =  1UL							\
 } }

 #define cpus_addr(src) ((src).bits)

 #define cpumask_scnprintf(buf, len, src) \
 			__cpumask_scnprintf((buf), (len), &(src), NR_CPUS)
 static inline int __cpumask_scnprintf(char *buf, int len,
 					const cpumask_t *srcp, int nbits)
 {
 	return bitmap_scnprintf(buf, len, srcp->bits, nbits);
 }

 #define cpumask_scnprintf_len(len) \
 			__cpumask_scnprintf_len((len))
 static inline int __cpumask_scnprintf_len(int len)
 {
 	return bitmap_scnprintf_len(len);
 }

 #define cpumask_parse_user(ubuf, ulen, dst) \
 			__cpumask_parse_user((ubuf), (ulen), &(dst), NR_CPUS)
 static inline int __cpumask_parse_user(const char __user *buf, int len,
 					cpumask_t *dstp, int nbits)
 {
 	return bitmap_parse_user(buf, len, dstp->bits, nbits);
 }

 #define cpulist_scnprintf(buf, len, src) \
 			__cpulist_scnprintf((buf), (len), &(src), NR_CPUS)
 static inline int __cpulist_scnprintf(char *buf, int len,
 					const cpumask_t *srcp, int nbits)
 {
 	return bitmap_scnlistprintf(buf, len, srcp->bits, nbits);
 }

 #define cpulist_parse(buf, dst) __cpulist_parse((buf), &(dst), NR_CPUS)
 static inline int __cpulist_parse(const char *buf, cpumask_t *dstp, int nbits)
 {
 	return bitmap_parselist(buf, dstp->bits, nbits);
 }

 #define cpu_remap(oldbit, old, new) \
 		__cpu_remap((oldbit), &(old), &(new), NR_CPUS)
 static inline int __cpu_remap(int oldbit,
 		const cpumask_t *oldp, const cpumask_t *newp, int nbits)
 {
 	return bitmap_bitremap(oldbit, oldp->bits, newp->bits, nbits);
 }

 #define cpus_remap(dst, src, old, new) \
 		__cpus_remap(&(dst), &(src), &(old), &(new), NR_CPUS)
 static inline void __cpus_remap(cpumask_t *dstp, const cpumask_t *srcp,
 		const cpumask_t *oldp, const cpumask_t *newp, int nbits)
 {
 	bitmap_remap(dstp->bits, srcp->bits, oldp->bits, newp->bits, nbits);
 }

 #define cpus_onto(dst, orig, relmap) \
 		__cpus_onto(&(dst), &(orig), &(relmap), NR_CPUS)
 static inline void __cpus_onto(cpumask_t *dstp, const cpumask_t *origp,
 		const cpumask_t *relmapp, int nbits)
 {
 	bitmap_onto(dstp->bits, origp->bits, relmapp->bits, nbits);
 }

 #define cpus_fold(dst, orig, sz) \
 		__cpus_fold(&(dst), &(orig), sz, NR_CPUS)
 static inline void __cpus_fold(cpumask_t *dstp, const cpumask_t *origp,
 		int sz, int nbits)
 {
 	bitmap_fold(dstp->bits, origp->bits, sz, nbits);
 }

 #if NR_CPUS > 1
 #define for_each_cpu_mask(cpu, mask)		\
 	for ((cpu) = first_cpu(mask);		\
 		(cpu) < NR_CPUS;		\
 		(cpu) = next_cpu((cpu), (mask)))
 #else /* NR_CPUS == 1 */
 #define for_each_cpu_mask(cpu, mask)		\
 	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
 #endif /* NR_CPUS */

 /*
  * The following particular system cpumasks and operations manage
  * possible, present and online cpus.  Each of them is a fixed size
  * bitmap of size NR_CPUS.
  *
  *  #ifdef CONFIG_HOTPLUG_CPU
  *     cpu_possible_map - has bit 'cpu' set iff cpu is populatable
  *     cpu_present_map  - has bit 'cpu' set iff cpu is populated
  *     cpu_online_map   - has bit 'cpu' set iff cpu available to scheduler
  *  #else
  *     cpu_possible_map - has bit 'cpu' set iff cpu is populated
  *     cpu_present_map  - copy of cpu_possible_map
  *     cpu_online_map   - has bit 'cpu' set iff cpu available to scheduler
  *  #endif
  *
  *  In either case, NR_CPUS is fixed at compile time, as the static
  *  size of these bitmaps.  The cpu_possible_map 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_map is dynamic(*), representing which CPUs
  *  are currently plugged in.  And cpu_online_map is the dynamic
  *  subset of cpu_present_map, indicating those CPUs available
  *  for scheduling.
  *
  *  If HOTPLUG is enabled, then cpu_possible_map 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_map varies dynamically,
  *  depending on what ACPI reports as currently plugged in, otherwise
  *  cpu_present_map is just a copy of cpu_possible_map.
  *
  *  (*) Well, cpu_present_map is dynamic in the hotplug case.  If not
  *      hotplug, it's a copy of cpu_possible_map, 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}_maps 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.
  * 2) Most SMP arch's #define some of these maps to be some
  *    other map specific to that arch.  Therefore, the following
  *    must be #define macros, not inlines.  To see why, examine
  *    the assembly code produced by the following.  Note that
  *    set1() writes phys_x_map, but set2() writes x_map:
  *        int x_map, phys_x_map;
  *        #define set1(a) x_map = a
  *        inline void set2(int a) { x_map = a; }
  *        #define x_map phys_x_map
  *        main(){ set1(3); set2(5); }
  */

 extern cpumask_t cpu_possible_map;
 extern cpumask_t cpu_online_map;
 extern cpumask_t cpu_present_map;

 #if NR_CPUS > 1
 #define num_online_cpus()	cpus_weight(cpu_online_map)
 #define num_possible_cpus()	cpus_weight(cpu_possible_map)
 #define num_present_cpus()	cpus_weight(cpu_present_map)
 #define cpu_online(cpu)		cpu_isset((cpu), cpu_online_map)
 #define cpu_possible(cpu)	cpu_isset((cpu), cpu_possible_map)
 #define cpu_present(cpu)	cpu_isset((cpu), cpu_present_map)
 #else
 #define num_online_cpus()	1
 #define num_possible_cpus()	1
 #define num_present_cpus()	1
 #define cpu_online(cpu)		((cpu) == 0)
 #define cpu_possible(cpu)	((cpu) == 0)
 #define cpu_present(cpu)	((cpu) == 0)
 #endif

 #define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))

 #ifdef CONFIG_SMP
 extern int nr_cpu_ids;
 #define any_online_cpu(mask) __any_online_cpu(&(mask))
 int __any_online_cpu(const cpumask_t *mask);
 #else
 #define nr_cpu_ids			1
 #define any_online_cpu(mask)		0
 #endif

 #define for_each_possible_cpu(cpu)  for_each_cpu_mask((cpu), cpu_possible_map)
 #define for_each_online_cpu(cpu)  for_each_cpu_mask((cpu), cpu_online_map)
 #define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map)

 #endif /* __LINUX_CPUMASK_H */
	#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.
	*
	* See detailed comments in the file linux/bitmap.h describing the
	* data type on which these cpumasks are based.
	*
	* For details of cpumask_scnprintf() and cpumask_parse_user(),
	* see bitmap_scnprintf() and bitmap_parse_user() in lib/bitmap.c.
	* For details of cpulist_scnprintf() and cpulist_parse(), see
	* bitmap_scnlistprintf() and bitmap_parselist(), also in bitmap.c.
	* For details of cpu_remap(), see bitmap_bitremap in lib/bitmap.c
	* For details of cpus_remap(), see bitmap_remap in lib/bitmap.c.
	* For details of cpus_onto(), see bitmap_onto in lib/bitmap.c.
	* For details of cpus_fold(), see bitmap_fold in lib/bitmap.c.
	*
	* The available cpumask operations are:
	*
	* void cpu_set(cpu, mask) turn on bit 'cpu' in mask
	* void cpu_clear(cpu, mask) turn off bit 'cpu' in mask
	* void cpus_setall(mask) set all bits
	* void cpus_clear(mask) clear all bits
	* int cpu_isset(cpu, mask) true iff bit 'cpu' set in mask
	* int cpu_test_and_set(cpu, mask) test and set bit 'cpu' in mask
	*
	* void cpus_and(dst, src1, src2) dst = src1 & src2 [intersection]
	* void cpus_or(dst, src1, src2) dst = src1 \| src2 [union]
	* void cpus_xor(dst, src1, src2) dst = src1 ^ src2
	* void cpus_andnot(dst, src1, src2) dst = src1 & ~src2
	* void cpus_complement(dst, src) dst = ~src
	*
	* int cpus_equal(mask1, mask2) Does mask1 == mask2?
	* int cpus_intersects(mask1, mask2) Do mask1 and mask2 intersect?
	* int cpus_subset(mask1, mask2) Is mask1 a subset of mask2?
	* int cpus_empty(mask) Is mask empty (no bits sets)?
	* int cpus_full(mask) Is mask full (all bits sets)?
	* int cpus_weight(mask) Hamming weigh - number of set bits
	*
	* void cpus_shift_right(dst, src, n) Shift right
	* void cpus_shift_left(dst, src, n) Shift left
	*
	* int first_cpu(mask) Number lowest set bit, or NR_CPUS
	* int next_cpu(cpu, mask) Next cpu past 'cpu', or NR_CPUS
	*
	* cpumask_t cpumask_of_cpu(cpu) Return cpumask with bit 'cpu' set
	* CPU_MASK_ALL Initializer - all bits set
	* CPU_MASK_NONE Initializer - no bits set
	* unsigned long *cpus_addr(mask) Array of unsigned long's in mask
	*
	* int cpumask_scnprintf(buf, len, mask) Format cpumask for printing
	* int cpumask_parse_user(ubuf, ulen, mask) Parse ascii string as cpumask
	* int cpulist_scnprintf(buf, len, mask) Format cpumask as list for printing
	* int cpulist_parse(buf, map) Parse ascii string as cpulist
	* int cpu_remap(oldbit, old, new) newbit = map(old, new)(oldbit)
	* void cpus_remap(dst, src, old, new) *dst = map(old, new)(src)
	* void cpus_onto(dst, orig, relmap) *dst = orig relative to relmap
	* void cpus_fold(dst, orig, sz) dst bits = orig bits mod sz
	*
	* for_each_cpu_mask(cpu, mask) for-loop cpu over mask
	*
	* int num_online_cpus() Number of online CPUs
	* int num_possible_cpus() Number of all possible CPUs
	* int num_present_cpus() Number of present CPUs
	*
	* int cpu_online(cpu) Is some cpu online?
	* int cpu_possible(cpu) Is some cpu possible?
	* int cpu_present(cpu) Is some cpu present (can schedule)?
	*
	* int any_online_cpu(mask) First online cpu in mask
	*
	* for_each_possible_cpu(cpu) for-loop cpu over cpu_possible_map
	* for_each_online_cpu(cpu) for-loop cpu over cpu_online_map
	* for_each_present_cpu(cpu) for-loop cpu over cpu_present_map
	*
	* Subtlety:
	* 1) The 'type-checked' form of cpu_isset() causes gcc (3.3.2, anyway)
	* to generate slightly worse code. Note for example the additional
	* 40 lines of assembly code compiling the "for each possible cpu"
	* loops buried in the disk_stat_read() macros calls when compiling
	* drivers/block/genhd.c (arch i386, CONFIG_SMP=y). So use a simple
	* one-line #define for cpu_isset(), instead of wrapping an inline
	* inside a macro, the way we do the other calls.
	*/

	#include <linux/kernel.h>
	#include <linux/threads.h>
	#include <linux/bitmap.h>

	typedef struct { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t;
	extern cpumask_t _unused_cpumask_arg_;

	#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 void __cpus_and(cpumask_t dstp, const cpumask_t src1p,
	const cpumask_t *src2p, int nbits)
	{
	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 void __cpus_andnot(cpumask_t dstp, const cpumask_t src1p,
	const cpumask_t *src2p, int nbits)
	{
	bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
	}

	#define cpus_complement(dst, src) __cpus_complement(&(dst), &(src), NR_CPUS)
	static inline void __cpus_complement(cpumask_t *dstp,
	const cpumask_t *srcp, int nbits)
	{
	bitmap_complement(dstp->bits, srcp->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_full(cpumask) __cpus_full(&(cpumask), NR_CPUS)
	static inline int __cpus_full(const cpumask_t *srcp, int nbits)
	{
	return bitmap_full(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_right(dst, src, n) \
	__cpus_shift_right(&(dst), &(src), (n), NR_CPUS)
	static inline void __cpus_shift_right(cpumask_t *dstp,
	const cpumask_t *srcp, int n, int nbits)
	{
	bitmap_shift_right(dstp->bits, srcp->bits, n, 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);
	}

	#ifdef CONFIG_SMP
	int __first_cpu(const cpumask_t *srcp);
	#define first_cpu(src) __first_cpu(&(src))
	int __next_cpu(int n, const cpumask_t *srcp);
	#define next_cpu(n, src) __next_cpu((n), &(src))
	#else
	#define first_cpu(src) ({ (void)(src); 0; })
	#define next_cpu(n, src) ({ (void)(src); 1; })
	#endif

	#ifdef CONFIG_HAVE_CPUMASK_OF_CPU_MAP
	extern cpumask_t *cpumask_of_cpu_map;
	#define cpumask_of_cpu(cpu) (cpumask_of_cpu_map[cpu])

	#else
	#define cpumask_of_cpu(cpu) \
	(*({ \
	typeof(_unused_cpumask_arg_) m; \
	if (sizeof(m) == sizeof(unsigned long)) { \
	m.bits[0] = 1UL<<(cpu); \
	} else { \
	cpus_clear(m); \
	cpu_set((cpu), m); \
	} \
	&m; \
	}))
	#endif

	#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 \
	} }

	#define CPU_MASK_ALL_PTR (&CPU_MASK_ALL)

	#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 \
	} }

	/* cpu_mask_all is in init/main.c */
	extern cpumask_t cpu_mask_all;
	#define CPU_MASK_ALL_PTR (&cpu_mask_all)

	#endif

	#define CPU_MASK_NONE \
	(cpumask_t) { { \
	[0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \
	} }

	#define CPU_MASK_CPU0 \
	(cpumask_t) { { \
	[0] = 1UL \
	} }

	#define cpus_addr(src) ((src).bits)

	#define cpumask_scnprintf(buf, len, src) \
	__cpumask_scnprintf((buf), (len), &(src), NR_CPUS)
	static inline int __cpumask_scnprintf(char *buf, int len,
	const cpumask_t *srcp, int nbits)
	{
	return bitmap_scnprintf(buf, len, srcp->bits, nbits);
	}

	#define cpumask_scnprintf_len(len) \
	__cpumask_scnprintf_len((len))
	static inline int __cpumask_scnprintf_len(int len)
	{
	return bitmap_scnprintf_len(len);
	}

	#define cpumask_parse_user(ubuf, ulen, dst) \
	__cpumask_parse_user((ubuf), (ulen), &(dst), NR_CPUS)
	static inline int __cpumask_parse_user(const char __user *buf, int len,
	cpumask_t *dstp, int nbits)
	{
	return bitmap_parse_user(buf, len, dstp->bits, nbits);
	}

	#define cpulist_scnprintf(buf, len, src) \
	__cpulist_scnprintf((buf), (len), &(src), NR_CPUS)
	static inline int __cpulist_scnprintf(char *buf, int len,
	const cpumask_t *srcp, int nbits)
	{
	return bitmap_scnlistprintf(buf, len, srcp->bits, nbits);
	}

	#define cpulist_parse(buf, dst) __cpulist_parse((buf), &(dst), NR_CPUS)
	static inline int __cpulist_parse(const char buf, cpumask_t dstp, int nbits)
	{
	return bitmap_parselist(buf, dstp->bits, nbits);
	}

	#define cpu_remap(oldbit, old, new) \
	__cpu_remap((oldbit), &(old), &(new), NR_CPUS)
	static inline int __cpu_remap(int oldbit,
	const cpumask_t oldp, const cpumask_t newp, int nbits)
	{
	return bitmap_bitremap(oldbit, oldp->bits, newp->bits, nbits);
	}

	#define cpus_remap(dst, src, old, new) \
	__cpus_remap(&(dst), &(src), &(old), &(new), NR_CPUS)
	static inline void __cpus_remap(cpumask_t dstp, const cpumask_t srcp,
	const cpumask_t oldp, const cpumask_t newp, int nbits)
	{
	bitmap_remap(dstp->bits, srcp->bits, oldp->bits, newp->bits, nbits);
	}

	#define cpus_onto(dst, orig, relmap) \
	__cpus_onto(&(dst), &(orig), &(relmap), NR_CPUS)
	static inline void __cpus_onto(cpumask_t dstp, const cpumask_t origp,
	const cpumask_t *relmapp, int nbits)
	{
	bitmap_onto(dstp->bits, origp->bits, relmapp->bits, nbits);
	}

	#define cpus_fold(dst, orig, sz) \
	__cpus_fold(&(dst), &(orig), sz, NR_CPUS)
	static inline void __cpus_fold(cpumask_t dstp, const cpumask_t origp,
	int sz, int nbits)
	{
	bitmap_fold(dstp->bits, origp->bits, sz, nbits);
	}

	#if NR_CPUS > 1
	#define for_each_cpu_mask(cpu, mask) \
	for ((cpu) = first_cpu(mask); \
	(cpu) < NR_CPUS; \
	(cpu) = next_cpu((cpu), (mask)))
	#else /* NR_CPUS == 1 */
	#define for_each_cpu_mask(cpu, mask) \
	for ((cpu) = 0; (cpu) < 1; (cpu)++, (void)mask)
	#endif /* NR_CPUS */

	/*
	* The following particular system cpumasks and operations manage
	* possible, present and online cpus. Each of them is a fixed size
	* bitmap of size NR_CPUS.
	*
	* #ifdef CONFIG_HOTPLUG_CPU
	* cpu_possible_map - has bit 'cpu' set iff cpu is populatable
	* cpu_present_map - has bit 'cpu' set iff cpu is populated
	* cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
	* #else
	* cpu_possible_map - has bit 'cpu' set iff cpu is populated
	* cpu_present_map - copy of cpu_possible_map
	* cpu_online_map - has bit 'cpu' set iff cpu available to scheduler
	* #endif
	*
	* In either case, NR_CPUS is fixed at compile time, as the static
	* size of these bitmaps. The cpu_possible_map 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_map is dynamic(*), representing which CPUs
	* are currently plugged in. And cpu_online_map is the dynamic
	* subset of cpu_present_map, indicating those CPUs available
	* for scheduling.
	*
	* If HOTPLUG is enabled, then cpu_possible_map 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_map varies dynamically,
	* depending on what ACPI reports as currently plugged in, otherwise
	* cpu_present_map is just a copy of cpu_possible_map.
	*
	* (*) Well, cpu_present_map is dynamic in the hotplug case. If not
	* hotplug, it's a copy of cpu_possible_map, 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}_maps 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.
	* 2) Most SMP arch's #define some of these maps to be some
	* other map specific to that arch. Therefore, the following
	* must be #define macros, not inlines. To see why, examine
	* the assembly code produced by the following. Note that
	* set1() writes phys_x_map, but set2() writes x_map:
	* int x_map, phys_x_map;
	* #define set1(a) x_map = a
	* inline void set2(int a) { x_map = a; }
	* #define x_map phys_x_map
	* main(){ set1(3); set2(5); }
	*/

	extern cpumask_t cpu_possible_map;
	extern cpumask_t cpu_online_map;
	extern cpumask_t cpu_present_map;

	#if NR_CPUS > 1
	#define num_online_cpus() cpus_weight(cpu_online_map)
	#define num_possible_cpus() cpus_weight(cpu_possible_map)
	#define num_present_cpus() cpus_weight(cpu_present_map)
	#define cpu_online(cpu) cpu_isset((cpu), cpu_online_map)
	#define cpu_possible(cpu) cpu_isset((cpu), cpu_possible_map)
	#define cpu_present(cpu) cpu_isset((cpu), cpu_present_map)
	#else
	#define num_online_cpus() 1
	#define num_possible_cpus() 1
	#define num_present_cpus() 1
	#define cpu_online(cpu) ((cpu) == 0)
	#define cpu_possible(cpu) ((cpu) == 0)
	#define cpu_present(cpu) ((cpu) == 0)
	#endif

	#define cpu_is_offline(cpu) unlikely(!cpu_online(cpu))

	#ifdef CONFIG_SMP
	extern int nr_cpu_ids;
	#define any_online_cpu(mask) __any_online_cpu(&(mask))
	int __any_online_cpu(const cpumask_t *mask);
	#else
	#define nr_cpu_ids 1
	#define any_online_cpu(mask) 0
	#endif

	#define for_each_possible_cpu(cpu) for_each_cpu_mask((cpu), cpu_possible_map)
	#define for_each_online_cpu(cpu) for_each_cpu_mask((cpu), cpu_online_map)
	#define for_each_present_cpu(cpu) for_each_cpu_mask((cpu), cpu_present_map)

	#endif /* __LINUX_CPUMASK_H */