include/linux/cpumask.h
changeset 0 aa628870c1d3
child 2 d1f6d8b6f81c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/linux/cpumask.h	Sun Jan 11 20:20:11 2009 +0100
@@ -0,0 +1,1085 @@
+#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.
+ *
+ * The new cpumask_ ops take a "struct cpumask *"; the old ones
+ * use cpumask_t.
+ *
+ * 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.
+ *
+ * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
+ * Note: The alternate operations with the suffix "_nr" are used
+ *       to limit the range of the loop to nr_cpu_ids instead of
+ *       NR_CPUS when NR_CPUS > 64 for performance reasons.
+ *       If NR_CPUS is <= 64 then most assembler bitmask
+ *       operators execute faster with a constant range, so
+ *       the operator will continue to use NR_CPUS.
+ *
+ *       Another consideration is that nr_cpu_ids is initialized
+ *       to NR_CPUS and isn't lowered until the possible cpus are
+ *       discovered (including any disabled cpus).  So early uses
+ *       will span the entire range of NR_CPUS.
+ * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
+ *
+ * The obsolescent 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
+ * int cpus_weight_nr(mask)		Same using nr_cpu_ids instead of NR_CPUS
+ *
+ * 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
+ * int next_cpu_nr(cpu, mask)		Next cpu past 'cpu', or nr_cpu_ids
+ *
+ * cpumask_t cpumask_of_cpu(cpu)	Return cpumask with bit 'cpu' set
+ *					(can be used as an lvalue)
+ * 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
+ *
+ * CPUMASK_ALLOC kmalloc's a structure that is a composite of many cpumask_t
+ * variables, and CPUMASK_PTR provides pointers to each field.
+ *
+ * The structure should be defined something like this:
+ * struct my_cpumasks {
+ *	cpumask_t mask1;
+ *	cpumask_t mask2;
+ * };
+ *
+ * Usage is then:
+ *	CPUMASK_ALLOC(my_cpumasks);
+ *	CPUMASK_PTR(mask1, my_cpumasks);
+ *	CPUMASK_PTR(mask2, my_cpumasks);
+ *
+ *	--- DO NOT reference cpumask_t pointers until this check ---
+ *	if (my_cpumasks == NULL)
+ *		"kmalloc failed"...
+ *
+ * References are now pointers to the cpumask_t variables (*mask1, ...)
+ *
+ *if NR_CPUS > BITS_PER_LONG
+ *   CPUMASK_ALLOC(m)			Declares and allocates struct m *m =
+ *						kmalloc(sizeof(*m), GFP_KERNEL)
+ *   CPUMASK_FREE(m)			Macro for kfree(m)
+ *else
+ *   CPUMASK_ALLOC(m)			Declares struct m _m, *m = &_m
+ *   CPUMASK_FREE(m)			Nop
+ *endif
+ *   CPUMASK_PTR(v, m)			Declares cpumask_t *v = &(m->v)
+ * ------------------------------------------------------------------------
+ *
+ * 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 using NR_CPUS
+ * for_each_cpu_mask_nr(cpu, mask)	for-loop cpu over mask using nr_cpu_ids
+ *
+ * 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 cpumask { 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);
+}
+
+/*
+ * 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 cpumask_t *get_cpu_mask(unsigned int cpu)
+{
+	const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG];
+	p -= cpu / BITS_PER_LONG;
+	return (const cpumask_t *)p;
+}
+
+/*
+ * In cases where we take the address of the cpumask immediately,
+ * gcc optimizes it out (it's a constant) and there's no huge stack
+ * variable created:
+ */
+#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			\
+} }
+
+#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)
+
+#if NR_CPUS > BITS_PER_LONG
+#define	CPUMASK_ALLOC(m)	struct m *m = kmalloc(sizeof(*m), GFP_KERNEL)
+#define	CPUMASK_FREE(m)		kfree(m)
+#else
+#define	CPUMASK_ALLOC(m)	struct m _m, *m = &_m
+#define	CPUMASK_FREE(m)
+#endif
+#define	CPUMASK_PTR(v, m) 	cpumask_t *v = &(m->v)
+
+#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_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 nr_cpu_ids		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 */
+
+extern int nr_cpu_ids;
+int __first_cpu(const cpumask_t *srcp);
+int __next_cpu(int n, const cpumask_t *srcp);
+int __any_online_cpu(const cpumask_t *mask);
+
+#define first_cpu(src)		__first_cpu(&(src))
+#define next_cpu(n, src)	__next_cpu((n), &(src))
+#define any_online_cpu(mask) __any_online_cpu(&(mask))
+#define for_each_cpu_mask(cpu, mask)			\
+	for ((cpu) = -1;				\
+		(cpu) = next_cpu((cpu), (mask)),	\
+		(cpu) < NR_CPUS; )
+#endif
+
+#if NR_CPUS <= 64
+
+#define next_cpu_nr(n, src)		next_cpu(n, src)
+#define cpus_weight_nr(cpumask)		cpus_weight(cpumask)
+#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 next_cpu_nr(n, src)	__next_cpu_nr((n), &(src))
+#define cpus_weight_nr(cpumask)	__cpus_weight(&(cpumask), nr_cpu_ids)
+#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 */
+
+/*
+ * The following particular system cpumasks and operations manage
+ * possible, present, active 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
+ *     cpu_active_map   - has bit 'cpu' set iff cpu available to migration
+ *  #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;
+extern cpumask_t cpu_active_map;
+
+#if NR_CPUS > 1
+#define num_online_cpus()	cpus_weight_nr(cpu_online_map)
+#define num_possible_cpus()	cpus_weight_nr(cpu_possible_map)
+#define num_present_cpus()	cpus_weight_nr(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)
+#define cpu_active(cpu)		cpu_isset((cpu), cpu_active_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)
+#define cpu_active(cpu)		((cpu) == 0)
+#endif
+
+#define cpu_is_offline(cpu)	unlikely(!cpu_online(cpu))
+
+#define for_each_possible_cpu(cpu) for_each_cpu_mask_nr((cpu), cpu_possible_map)
+#define for_each_online_cpu(cpu)   for_each_cpu_mask_nr((cpu), cpu_online_map)
+#define for_each_present_cpu(cpu)  for_each_cpu_mask_nr((cpu), cpu_present_map)
+
+/* These are the new versions of the cpumask operators: passed by pointer.
+ * The older versions will be implemented in terms of these, then deleted. */
+#define cpumask_bits(maskp) ((maskp)->bits)
+
+#if NR_CPUS <= BITS_PER_LONG
+#define CPU_BITS_ALL						\
+{								\
+	[BITS_TO_LONGS(NR_CPUS)-1] = CPU_MASK_LAST_WORD	\
+}
+
+/* This produces more efficient code. */
+#define nr_cpumask_bits	NR_CPUS
+
+#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		\
+}
+
+#define nr_cpumask_bits	nr_cpu_ids
+#endif /* NR_CPUS > BITS_PER_LONG */
+
+/* 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_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_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
+ *
+ * No static inline type checking - see Subtlety (1) above.
+ */
+#define cpumask_test_cpu(cpu, cpumask) \
+	test_bit(cpumask_check(cpu), (cpumask)->bits)
+
+/**
+ * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask
+ * @cpu: cpu number (< nr_cpu_ids)
+ * @cpumask: the cpumask pointer
+ *
+ * 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_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
+ */
+static inline void cpumask_and(struct cpumask *dstp,
+			       const struct cpumask *src1p,
+			       const struct cpumask *src2p)
+{
+	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
+ */
+static inline void cpumask_andnot(struct cpumask *dstp,
+				  const struct cpumask *src1p,
+				  const struct cpumask *src2p)
+{
+	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
+ */
+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))
+
+/**
+ * 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;
+}
+
+/**
+ * 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);
+ */
+#ifdef CONFIG_CPUMASK_OFFSTACK
+typedef struct cpumask *cpumask_var_t;
+
+bool alloc_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 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 */
+
+/* The pointer versions of the maps, these will become the primary versions. */
+#define cpu_possible_mask ((const struct cpumask *)&cpu_possible_map)
+#define cpu_online_mask ((const struct cpumask *)&cpu_online_map)
+#define cpu_present_mask ((const struct cpumask *)&cpu_present_map)
+#define cpu_active_mask ((const struct cpumask *)&cpu_active_map)
+
+/* 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])
+
+/* Wrappers for arch boot code to manipulate normally-constant masks */
+static inline void set_cpu_possible(unsigned int cpu, bool possible)
+{
+	if (possible)
+		cpumask_set_cpu(cpu, &cpu_possible_map);
+	else
+		cpumask_clear_cpu(cpu, &cpu_possible_map);
+}
+
+static inline void set_cpu_present(unsigned int cpu, bool present)
+{
+	if (present)
+		cpumask_set_cpu(cpu, &cpu_present_map);
+	else
+		cpumask_clear_cpu(cpu, &cpu_present_map);
+}
+
+static inline void set_cpu_online(unsigned int cpu, bool online)
+{
+	if (online)
+		cpumask_set_cpu(cpu, &cpu_online_map);
+	else
+		cpumask_clear_cpu(cpu, &cpu_online_map);
+}
+
+static inline void set_cpu_active(unsigned int cpu, bool active)
+{
+	if (active)
+		cpumask_set_cpu(cpu, &cpu_active_map);
+	else
+		cpumask_clear_cpu(cpu, &cpu_active_map);
+}
+
+static inline void init_cpu_present(const struct cpumask *src)
+{
+	cpumask_copy(&cpu_present_map, src);
+}
+
+static inline void init_cpu_possible(const struct cpumask *src)
+{
+	cpumask_copy(&cpu_possible_map, src);
+}
+
+static inline void init_cpu_online(const struct cpumask *src)
+{
+	cpumask_copy(&cpu_online_map, src);
+}
+#endif /* __LINUX_CPUMASK_H */