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Diffstat (limited to 'include/linux/cpumask.h')
| -rw-r--r-- | include/linux/cpumask.h | 395 |
1 files changed, 395 insertions, 0 deletions
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h new file mode 100644 index 000000000000..b15826f6e3a2 --- /dev/null +++ b/include/linux/cpumask.h @@ -0,0 +1,395 @@ +#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(), + * see bitmap_scnprintf() and bitmap_parse() in lib/bitmap.c. + * For details of cpulist_scnprintf() and cpulist_parse(), see + * bitmap_scnlistprintf() and bitmap_parselist(), also in 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(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 + * + * 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_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> +#include <asm/bug.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); +} + +#define first_cpu(src) __first_cpu(&(src), NR_CPUS) +static inline int __first_cpu(const cpumask_t *srcp, int nbits) +{ + return min_t(int, nbits, find_first_bit(srcp->bits, nbits)); +} + +#define next_cpu(n, src) __next_cpu((n), &(src), NR_CPUS) +static inline int __next_cpu(int n, const cpumask_t *srcp, int nbits) +{ + return min_t(int, nbits, find_next_bit(srcp->bits, nbits, n+1)); +} + +#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; \ +}) + +#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 \ +} } + +#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_parse(ubuf, ulen, dst) \ + __cpumask_parse((ubuf), (ulen), &(dst), NR_CPUS) +static inline int __cpumask_parse(const char __user *buf, int len, + cpumask_t *dstp, int nbits) +{ + return bitmap_parse(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); +} + +#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)++) +#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 - all NR_CPUS bits set + * 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 any_online_cpu(mask) \ +({ \ + int cpu; \ + for_each_cpu_mask(cpu, (mask)) \ + if (cpu_online(cpu)) \ + break; \ + cpu; \ +}) + +#define for_each_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 */ |