#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. * * . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . * 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 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 * 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 { 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) #endif /* __LINUX_CPUMASK_H */