diff options
Diffstat (limited to 'include/linux/cpumask.h')
| -rw-r--r-- | include/linux/cpumask.h | 1202 |
1 files changed, 1202 insertions, 0 deletions
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h new file mode 100644 index 000000000..c2aa0aa26 --- /dev/null +++ b/include/linux/cpumask.h @@ -0,0 +1,1202 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __LINUX_CPUMASK_H +#define __LINUX_CPUMASK_H + +/* + * Cpumasks provide a bitmap suitable for representing the + * set of CPU's in a system, one bit position per CPU number. In general, + * only nr_cpu_ids (<= NR_CPUS) bits are valid. + */ +#include <linux/kernel.h> +#include <linux/threads.h> +#include <linux/bitmap.h> +#include <linux/atomic.h> +#include <linux/bug.h> +#include <linux/gfp_types.h> +#include <linux/numa.h> + +/* Don't assign or return these: may not be this big! */ +typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t; + +/** + * cpumask_bits - get the bits in a cpumask + * @maskp: the struct cpumask * + * + * You should only assume nr_cpu_ids bits of this mask are valid. This is + * a macro so it's const-correct. + */ +#define cpumask_bits(maskp) ((maskp)->bits) + +/** + * cpumask_pr_args - printf args to output a cpumask + * @maskp: cpumask to be printed + * + * Can be used to provide arguments for '%*pb[l]' when printing a cpumask. + */ +#define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp) + +#if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS) +#define nr_cpu_ids ((unsigned int)NR_CPUS) +#else +extern unsigned int nr_cpu_ids; +#endif + +static inline void set_nr_cpu_ids(unsigned int nr) +{ +#if (NR_CPUS == 1) || defined(CONFIG_FORCE_NR_CPUS) + WARN_ON(nr != nr_cpu_ids); +#else + nr_cpu_ids = nr; +#endif +} + +/* Deprecated. Always use nr_cpu_ids. */ +#define nr_cpumask_bits nr_cpu_ids + +/* + * The following particular system cpumasks and operations manage + * possible, present, active and online cpus. + * + * cpu_possible_mask- has bit 'cpu' set iff cpu is populatable + * cpu_present_mask - has bit 'cpu' set iff cpu is populated + * cpu_online_mask - has bit 'cpu' set iff cpu available to scheduler + * cpu_active_mask - has bit 'cpu' set iff cpu available to migration + * + * If !CONFIG_HOTPLUG_CPU, present == possible, and active == online. + * + * The cpu_possible_mask is fixed at boot time, as the set of CPU id's + * that it is possible might ever be plugged in at anytime during the + * life of that system boot. The cpu_present_mask is dynamic(*), + * representing which CPUs are currently plugged in. And + * cpu_online_mask is the dynamic subset of cpu_present_mask, + * indicating those CPUs available for scheduling. + * + * If HOTPLUG is enabled, then cpu_present_mask varies dynamically, + * depending on what ACPI reports as currently plugged in, otherwise + * cpu_present_mask is just a copy of cpu_possible_mask. + * + * (*) Well, cpu_present_mask is dynamic in the hotplug case. If not + * hotplug, it's a copy of cpu_possible_mask, hence fixed at boot. + * + * Subtleties: + * 1) UP arch's (NR_CPUS == 1, CONFIG_SMP not defined) hardcode + * assumption that their single CPU is online. The UP + * cpu_{online,possible,present}_masks are placebos. Changing them + * will have no useful affect on the following num_*_cpus() + * and cpu_*() macros in the UP case. This ugliness is a UP + * optimization - don't waste any instructions or memory references + * asking if you're online or how many CPUs there are if there is + * only one CPU. + */ + +extern struct cpumask __cpu_possible_mask; +extern struct cpumask __cpu_online_mask; +extern struct cpumask __cpu_present_mask; +extern struct cpumask __cpu_active_mask; +extern struct cpumask __cpu_dying_mask; +#define cpu_possible_mask ((const struct cpumask *)&__cpu_possible_mask) +#define cpu_online_mask ((const struct cpumask *)&__cpu_online_mask) +#define cpu_present_mask ((const struct cpumask *)&__cpu_present_mask) +#define cpu_active_mask ((const struct cpumask *)&__cpu_active_mask) +#define cpu_dying_mask ((const struct cpumask *)&__cpu_dying_mask) + +extern atomic_t __num_online_cpus; + +extern cpumask_t cpus_booted_once_mask; + +static __always_inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits) +{ +#ifdef CONFIG_DEBUG_PER_CPU_MAPS + WARN_ON_ONCE(cpu >= bits); +#endif /* CONFIG_DEBUG_PER_CPU_MAPS */ +} + +/* verify cpu argument to cpumask_* operators */ +static __always_inline unsigned int cpumask_check(unsigned int cpu) +{ + cpu_max_bits_warn(cpu, nr_cpumask_bits); + return cpu; +} + +/** + * 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_first_zero - get the first unset cpu in a cpumask + * @srcp: the cpumask pointer + * + * Returns >= nr_cpu_ids if all cpus are set. + */ +static inline unsigned int cpumask_first_zero(const struct cpumask *srcp) +{ + return find_first_zero_bit(cpumask_bits(srcp), nr_cpumask_bits); +} + +/** + * 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(). + */ +static inline +unsigned int cpumask_first_and(const struct cpumask *srcp1, const struct cpumask *srcp2) +{ + return find_first_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), nr_cpumask_bits); +} + +/** + * cpumask_last - get the last CPU in a cpumask + * @srcp: - the cpumask pointer + * + * Returns >= nr_cpumask_bits if no CPUs set. + */ +static inline unsigned int cpumask_last(const struct cpumask *srcp) +{ + return find_last_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); +} + +#if NR_CPUS == 1 +/* Uniprocessor: there is only one valid CPU */ +static inline unsigned int cpumask_local_spread(unsigned int i, int node) +{ + return 0; +} + +static inline unsigned int cpumask_any_and_distribute(const struct cpumask *src1p, + const struct cpumask *src2p) +{ + return cpumask_first_and(src1p, src2p); +} + +static inline unsigned int cpumask_any_distribute(const struct cpumask *srcp) +{ + return cpumask_first(srcp); +} +#else +unsigned int cpumask_local_spread(unsigned int i, int node); +unsigned int cpumask_any_and_distribute(const struct cpumask *src1p, + const struct cpumask *src2p); +unsigned int cpumask_any_distribute(const struct cpumask *srcp); +#endif /* NR_CPUS */ + +/** + * cpumask_next_and - get the next cpu in *src1p & *src2p + * @n: the cpu prior to the place to search (ie. return will be > @n) + * @src1p: the first cpumask pointer + * @src2p: the second cpumask pointer + * + * Returns >= nr_cpu_ids if no further cpus set in both. + */ +static inline +unsigned int cpumask_next_and(int n, const struct cpumask *src1p, + const struct cpumask *src2p) +{ + /* -1 is a legal arg here. */ + if (n != -1) + cpumask_check(n); + return find_next_and_bit(cpumask_bits(src1p), cpumask_bits(src2p), + nr_cpumask_bits, n + 1); +} + +/** + * 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_each_set_bit(cpu, cpumask_bits(mask), nr_cpumask_bits) + +/** + * for_each_cpu_not - iterate over every cpu in a complemented mask + * @cpu: the (optionally unsigned) integer iterator + * @mask: the cpumask pointer + * + * After the loop, cpu is >= nr_cpu_ids. + */ +#define for_each_cpu_not(cpu, mask) \ + for_each_clear_bit(cpu, cpumask_bits(mask), nr_cpumask_bits) + +#if NR_CPUS == 1 +static inline +unsigned int cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap) +{ + cpumask_check(start); + if (n != -1) + cpumask_check(n); + + /* + * Return the first available CPU when wrapping, or when starting before cpu0, + * since there is only one valid option. + */ + if (wrap && n >= 0) + return nr_cpumask_bits; + + return cpumask_first(mask); +} +#else +unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int start, bool wrap); +#endif + +/** + * for_each_cpu_wrap - iterate over every cpu in a mask, starting at a specified location + * @cpu: the (optionally unsigned) integer iterator + * @mask: the cpumask pointer + * @start: the start location + * + * The implementation does not assume any bit in @mask is set (including @start). + * + * After the loop, cpu is >= nr_cpu_ids. + */ +#define for_each_cpu_wrap(cpu, mask, start) \ + for_each_set_bit_wrap(cpu, cpumask_bits(mask), nr_cpumask_bits, start) + +/** + * for_each_cpu_and - iterate over every cpu in both masks + * @cpu: the (optionally unsigned) integer iterator + * @mask1: the first cpumask pointer + * @mask2: the second cpumask pointer + * + * This saves a temporary CPU mask in many places. It is equivalent to: + * struct cpumask tmp; + * cpumask_and(&tmp, &mask1, &mask2); + * for_each_cpu(cpu, &tmp) + * ... + * + * After the loop, cpu is >= nr_cpu_ids. + */ +#define for_each_cpu_and(cpu, mask1, mask2) \ + for_each_and_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), nr_cpumask_bits) + +/** + * for_each_cpu_andnot - iterate over every cpu present in one mask, excluding + * those present in another. + * @cpu: the (optionally unsigned) integer iterator + * @mask1: the first cpumask pointer + * @mask2: the second cpumask pointer + * + * This saves a temporary CPU mask in many places. It is equivalent to: + * struct cpumask tmp; + * cpumask_andnot(&tmp, &mask1, &mask2); + * for_each_cpu(cpu, &tmp) + * ... + * + * After the loop, cpu is >= nr_cpu_ids. + */ +#define for_each_cpu_andnot(cpu, mask1, mask2) \ + for_each_andnot_bit(cpu, cpumask_bits(mask1), cpumask_bits(mask2), nr_cpumask_bits) + +/** + * cpumask_any_but - return a "random" in a cpumask, but not this one. + * @mask: the cpumask to search + * @cpu: the cpu to ignore. + * + * Often used to find any cpu but smp_processor_id() in a mask. + * Returns >= nr_cpu_ids if no cpus set. + */ +static inline +unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu) +{ + unsigned int i; + + cpumask_check(cpu); + for_each_cpu(i, mask) + if (i != cpu) + break; + return i; +} + +/** + * cpumask_nth - get the first cpu in a cpumask + * @srcp: the cpumask pointer + * @cpu: the N'th cpu to find, starting from 0 + * + * Returns >= nr_cpu_ids if such cpu doesn't exist. + */ +static inline unsigned int cpumask_nth(unsigned int cpu, const struct cpumask *srcp) +{ + return find_nth_bit(cpumask_bits(srcp), nr_cpumask_bits, cpumask_check(cpu)); +} + +/** + * cpumask_nth_and - get the first cpu in 2 cpumasks + * @srcp1: the cpumask pointer + * @srcp2: the cpumask pointer + * @cpu: the N'th cpu to find, starting from 0 + * + * Returns >= nr_cpu_ids if such cpu doesn't exist. + */ +static inline +unsigned int cpumask_nth_and(unsigned int cpu, const struct cpumask *srcp1, + const struct cpumask *srcp2) +{ + return find_nth_and_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), + nr_cpumask_bits, cpumask_check(cpu)); +} + +/** + * cpumask_nth_andnot - get the first cpu set in 1st cpumask, and clear in 2nd. + * @srcp1: the cpumask pointer + * @srcp2: the cpumask pointer + * @cpu: the N'th cpu to find, starting from 0 + * + * Returns >= nr_cpu_ids if such cpu doesn't exist. + */ +static inline +unsigned int cpumask_nth_andnot(unsigned int cpu, const struct cpumask *srcp1, + const struct cpumask *srcp2) +{ + return find_nth_andnot_bit(cpumask_bits(srcp1), cpumask_bits(srcp2), + nr_cpumask_bits, cpumask_check(cpu)); +} + +#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 __always_inline void cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) +{ + set_bit(cpumask_check(cpu), cpumask_bits(dstp)); +} + +static __always_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 __always_inline void cpumask_clear_cpu(int cpu, struct cpumask *dstp) +{ + clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); +} + +static __always_inline void __cpumask_clear_cpu(int cpu, struct cpumask *dstp) +{ + __clear_bit(cpumask_check(cpu), cpumask_bits(dstp)); +} + +/** + * cpumask_test_cpu - test for a cpu in a cpumask + * @cpu: cpu number (< nr_cpu_ids) + * @cpumask: the cpumask pointer + * + * Returns true if @cpu is set in @cpumask, else returns false + */ +static __always_inline bool cpumask_test_cpu(int cpu, const struct cpumask *cpumask) +{ + return test_bit(cpumask_check(cpu), cpumask_bits((cpumask))); +} + +/** + * cpumask_test_and_set_cpu - atomically test and set a cpu in a cpumask + * @cpu: cpu number (< nr_cpu_ids) + * @cpumask: the cpumask pointer + * + * Returns true if @cpu is set in old bitmap of @cpumask, else returns false + * + * test_and_set_bit wrapper for cpumasks. + */ +static __always_inline bool cpumask_test_and_set_cpu(int cpu, struct cpumask *cpumask) +{ + return test_and_set_bit(cpumask_check(cpu), cpumask_bits(cpumask)); +} + +/** + * cpumask_test_and_clear_cpu - atomically test and clear a cpu in a cpumask + * @cpu: cpu number (< nr_cpu_ids) + * @cpumask: the cpumask pointer + * + * Returns true if @cpu is set in old bitmap of @cpumask, else returns false + * + * test_and_clear_bit wrapper for cpumasks. + */ +static __always_inline bool cpumask_test_and_clear_cpu(int cpu, struct cpumask *cpumask) +{ + return test_and_clear_bit(cpumask_check(cpu), cpumask_bits(cpumask)); +} + +/** + * cpumask_setall - set all cpus (< nr_cpu_ids) in a cpumask + * @dstp: the cpumask pointer + */ +static inline void cpumask_setall(struct cpumask *dstp) +{ + bitmap_fill(cpumask_bits(dstp), nr_cpumask_bits); +} + +/** + * cpumask_clear - clear all cpus (< nr_cpu_ids) in a cpumask + * @dstp: the cpumask pointer + */ +static inline void cpumask_clear(struct cpumask *dstp) +{ + bitmap_zero(cpumask_bits(dstp), nr_cpumask_bits); +} + +/** + * cpumask_and - *dstp = *src1p & *src2p + * @dstp: the cpumask result + * @src1p: the first input + * @src2p: the second input + * + * If *@dstp is empty, returns false, else returns true + */ +static inline bool cpumask_and(struct cpumask *dstp, + const struct cpumask *src1p, + const struct cpumask *src2p) +{ + return bitmap_and(cpumask_bits(dstp), cpumask_bits(src1p), + cpumask_bits(src2p), nr_cpumask_bits); +} + +/** + * cpumask_or - *dstp = *src1p | *src2p + * @dstp: the cpumask result + * @src1p: the first input + * @src2p: the second input + */ +static inline void cpumask_or(struct cpumask *dstp, const struct cpumask *src1p, + const struct cpumask *src2p) +{ + bitmap_or(cpumask_bits(dstp), cpumask_bits(src1p), + cpumask_bits(src2p), nr_cpumask_bits); +} + +/** + * cpumask_xor - *dstp = *src1p ^ *src2p + * @dstp: the cpumask result + * @src1p: the first input + * @src2p: the second input + */ +static inline void cpumask_xor(struct cpumask *dstp, + const struct cpumask *src1p, + const struct cpumask *src2p) +{ + bitmap_xor(cpumask_bits(dstp), cpumask_bits(src1p), + cpumask_bits(src2p), nr_cpumask_bits); +} + +/** + * cpumask_andnot - *dstp = *src1p & ~*src2p + * @dstp: the cpumask result + * @src1p: the first input + * @src2p: the second input + * + * If *@dstp is empty, returns false, else returns true + */ +static inline bool cpumask_andnot(struct cpumask *dstp, + const struct cpumask *src1p, + const struct cpumask *src2p) +{ + return bitmap_andnot(cpumask_bits(dstp), cpumask_bits(src1p), + cpumask_bits(src2p), nr_cpumask_bits); +} + +/** + * cpumask_complement - *dstp = ~*srcp + * @dstp: the cpumask result + * @srcp: the input to invert + */ +static inline void cpumask_complement(struct cpumask *dstp, + const struct cpumask *srcp) +{ + bitmap_complement(cpumask_bits(dstp), cpumask_bits(srcp), + nr_cpumask_bits); +} + +/** + * cpumask_equal - *src1p == *src2p + * @src1p: the first input + * @src2p: the second input + */ +static inline bool cpumask_equal(const struct cpumask *src1p, + const struct cpumask *src2p) +{ + return bitmap_equal(cpumask_bits(src1p), cpumask_bits(src2p), + nr_cpumask_bits); +} + +/** + * cpumask_or_equal - *src1p | *src2p == *src3p + * @src1p: the first input + * @src2p: the second input + * @src3p: the third input + */ +static inline bool cpumask_or_equal(const struct cpumask *src1p, + const struct cpumask *src2p, + const struct cpumask *src3p) +{ + return bitmap_or_equal(cpumask_bits(src1p), cpumask_bits(src2p), + cpumask_bits(src3p), nr_cpumask_bits); +} + +/** + * cpumask_intersects - (*src1p & *src2p) != 0 + * @src1p: the first input + * @src2p: the second input + */ +static inline bool cpumask_intersects(const struct cpumask *src1p, + const struct cpumask *src2p) +{ + return bitmap_intersects(cpumask_bits(src1p), cpumask_bits(src2p), + nr_cpumask_bits); +} + +/** + * cpumask_subset - (*src1p & ~*src2p) == 0 + * @src1p: the first input + * @src2p: the second input + * + * Returns true if *@src1p is a subset of *@src2p, else returns false + */ +static inline bool 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_weight_and - Count of bits in (*srcp1 & *srcp2) + * @srcp1: the cpumask to count bits (< nr_cpu_ids) in. + * @srcp2: the cpumask to count bits (< nr_cpu_ids) in. + */ +static inline unsigned int cpumask_weight_and(const struct cpumask *srcp1, + const struct cpumask *srcp2) +{ + return bitmap_weight_and(cpumask_bits(srcp1), cpumask_bits(srcp2), 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_any_and - pick a "random" cpu from *mask1 & *mask2 + * @mask1: the first input cpumask + * @mask2: the second input cpumask + * + * Returns >= nr_cpu_ids if no cpus set. + */ +#define cpumask_any_and(mask1, mask2) cpumask_first_and((mask1), (mask2)) + +/** + * cpumask_of - the cpumask containing just a given cpu + * @cpu: the cpu (<= nr_cpu_ids) + */ +#define cpumask_of(cpu) (get_cpu_mask(cpu)) + +/** + * cpumask_parse_user - extract a cpumask from a user string + * @buf: the buffer to extract from + * @len: the length of the buffer + * @dstp: the cpumask to set. + * + * Returns -errno, or 0 for success. + */ +static inline int cpumask_parse_user(const char __user *buf, int len, + struct cpumask *dstp) +{ + return bitmap_parse_user(buf, len, cpumask_bits(dstp), nr_cpumask_bits); +} + +/** + * cpumask_parselist_user - extract a cpumask from a user string + * @buf: the buffer to extract from + * @len: the length of the buffer + * @dstp: the cpumask to set. + * + * Returns -errno, or 0 for success. + */ +static inline int cpumask_parselist_user(const char __user *buf, int len, + struct cpumask *dstp) +{ + return bitmap_parselist_user(buf, len, cpumask_bits(dstp), + nr_cpumask_bits); +} + +/** + * cpumask_parse - extract a cpumask from a string + * @buf: the buffer to extract from + * @dstp: the cpumask to set. + * + * Returns -errno, or 0 for success. + */ +static inline int cpumask_parse(const char *buf, struct cpumask *dstp) +{ + return bitmap_parse(buf, UINT_MAX, cpumask_bits(dstp), nr_cpumask_bits); +} + +/** + * cpulist_parse - extract a cpumask from a user string of ranges + * @buf: the buffer to extract from + * @dstp: the cpumask to set. + * + * Returns -errno, or 0 for success. + */ +static inline int cpulist_parse(const char *buf, struct cpumask *dstp) +{ + return bitmap_parselist(buf, cpumask_bits(dstp), nr_cpumask_bits); +} + +/** + * cpumask_size - size to allocate for a 'struct cpumask' in bytes + */ +static inline unsigned int cpumask_size(void) +{ + return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long); +} + +/* + * cpumask_var_t: struct cpumask for stack usage. + * + * Oh, the wicked games we play! In order to make kernel coding a + * little more difficult, we typedef cpumask_var_t to an array or a + * pointer: doing &mask on an array is a noop, so it still works. + * + * ie. + * cpumask_var_t tmpmask; + * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) + * return -ENOMEM; + * + * ... use 'tmpmask' like a normal struct cpumask * ... + * + * free_cpumask_var(tmpmask); + * + * + * However, one notable exception is there. alloc_cpumask_var() allocates + * only nr_cpumask_bits bits (in the other hand, real cpumask_t always has + * NR_CPUS bits). Therefore you don't have to dereference cpumask_var_t. + * + * cpumask_var_t tmpmask; + * if (!alloc_cpumask_var(&tmpmask, GFP_KERNEL)) + * return -ENOMEM; + * + * var = *tmpmask; + * + * This code makes NR_CPUS length memcopy and brings to a memory corruption. + * cpumask_copy() provide safe copy functionality. + * + * Note that there is another evil here: If you define a cpumask_var_t + * as a percpu variable then the way to obtain the address of the cpumask + * structure differently influences what this_cpu_* operation needs to be + * used. Please use this_cpu_cpumask_var_t in those cases. The direct use + * of this_cpu_ptr() or this_cpu_read() will lead to failures when the + * other type of cpumask_var_t implementation is configured. + * + * Please also note that __cpumask_var_read_mostly can be used to declare + * a cpumask_var_t variable itself (not its content) as read mostly. + */ +#ifdef CONFIG_CPUMASK_OFFSTACK +typedef struct cpumask *cpumask_var_t; + +#define this_cpu_cpumask_var_ptr(x) this_cpu_read(x) +#define __cpumask_var_read_mostly __read_mostly + +bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node); + +static inline +bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, int node) +{ + return alloc_cpumask_var_node(mask, flags | __GFP_ZERO, node); +} + +/** + * alloc_cpumask_var - allocate a struct cpumask + * @mask: pointer to cpumask_var_t where the cpumask is returned + * @flags: GFP_ flags + * + * Only defined when CONFIG_CPUMASK_OFFSTACK=y, otherwise is + * a nop returning a constant 1 (in <linux/cpumask.h>). + * + * See alloc_cpumask_var_node. + */ +static inline +bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) +{ + return alloc_cpumask_var_node(mask, flags, NUMA_NO_NODE); +} + +static inline +bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) +{ + return alloc_cpumask_var(mask, flags | __GFP_ZERO); +} + +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); + +static inline bool cpumask_available(cpumask_var_t mask) +{ + return mask != NULL; +} + +#else +typedef struct cpumask cpumask_var_t[1]; + +#define this_cpu_cpumask_var_ptr(x) this_cpu_ptr(x) +#define __cpumask_var_read_mostly + +static inline bool alloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) +{ + return true; +} + +static inline bool alloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, + int node) +{ + return true; +} + +static inline bool zalloc_cpumask_var(cpumask_var_t *mask, gfp_t flags) +{ + cpumask_clear(*mask); + return true; +} + +static inline bool zalloc_cpumask_var_node(cpumask_var_t *mask, gfp_t flags, + int node) +{ + cpumask_clear(*mask); + return true; +} + +static inline void alloc_bootmem_cpumask_var(cpumask_var_t *mask) +{ +} + +static inline void free_cpumask_var(cpumask_var_t mask) +{ +} + +static inline void free_bootmem_cpumask_var(cpumask_var_t mask) +{ +} + +static inline bool cpumask_available(cpumask_var_t mask) +{ + return true; +} +#endif /* CONFIG_CPUMASK_OFFSTACK */ + +/* It's common to want to use cpu_all_mask in struct member initializers, + * so it has to refer to an address rather than a pointer. */ +extern const DECLARE_BITMAP(cpu_all_bits, NR_CPUS); +#define cpu_all_mask to_cpumask(cpu_all_bits) + +/* First bits of cpu_bit_bitmap are in fact unset. */ +#define cpu_none_mask to_cpumask(cpu_bit_bitmap[0]) + +#if NR_CPUS == 1 +/* Uniprocessor: the possible/online/present masks are always "1" */ +#define for_each_possible_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++) +#define for_each_online_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++) +#define for_each_present_cpu(cpu) for ((cpu) = 0; (cpu) < 1; (cpu)++) +#else +#define for_each_possible_cpu(cpu) for_each_cpu((cpu), cpu_possible_mask) +#define for_each_online_cpu(cpu) for_each_cpu((cpu), cpu_online_mask) +#define for_each_present_cpu(cpu) for_each_cpu((cpu), cpu_present_mask) +#endif + +/* Wrappers for arch boot code to manipulate normally-constant masks */ +void init_cpu_present(const struct cpumask *src); +void init_cpu_possible(const struct cpumask *src); +void init_cpu_online(const struct cpumask *src); + +static inline void reset_cpu_possible_mask(void) +{ + bitmap_zero(cpumask_bits(&__cpu_possible_mask), NR_CPUS); +} + +static inline void +set_cpu_possible(unsigned int cpu, bool possible) +{ + if (possible) + cpumask_set_cpu(cpu, &__cpu_possible_mask); + else + cpumask_clear_cpu(cpu, &__cpu_possible_mask); +} + +static inline void +set_cpu_present(unsigned int cpu, bool present) +{ + if (present) + cpumask_set_cpu(cpu, &__cpu_present_mask); + else + cpumask_clear_cpu(cpu, &__cpu_present_mask); +} + +void set_cpu_online(unsigned int cpu, bool online); + +static inline void +set_cpu_active(unsigned int cpu, bool active) +{ + if (active) + cpumask_set_cpu(cpu, &__cpu_active_mask); + else + cpumask_clear_cpu(cpu, &__cpu_active_mask); +} + +static inline void +set_cpu_dying(unsigned int cpu, bool dying) +{ + if (dying) + cpumask_set_cpu(cpu, &__cpu_dying_mask); + else + cpumask_clear_cpu(cpu, &__cpu_dying_mask); +} + +/** + * to_cpumask - convert an NR_CPUS bitmap to a struct cpumask * + * @bitmap: the bitmap + * + * There are a few places where cpumask_var_t isn't appropriate and + * static cpumasks must be used (eg. very early boot), yet we don't + * expose the definition of 'struct cpumask'. + * + * This does the conversion, and can be used as a constant initializer. + */ +#define to_cpumask(bitmap) \ + ((struct cpumask *)(1 ? (bitmap) \ + : (void *)sizeof(__check_is_bitmap(bitmap)))) + +static inline int __check_is_bitmap(const unsigned long *bitmap) +{ + return 1; +} + +/* + * Special-case data structure for "single bit set only" constant CPU masks. + * + * We pre-generate all the 64 (or 32) possible bit positions, with enough + * padding to the left and the right, and return the constant pointer + * appropriately offset. + */ +extern const unsigned long + cpu_bit_bitmap[BITS_PER_LONG+1][BITS_TO_LONGS(NR_CPUS)]; + +static inline const struct cpumask *get_cpu_mask(unsigned int cpu) +{ + const unsigned long *p = cpu_bit_bitmap[1 + cpu % BITS_PER_LONG]; + p -= cpu / BITS_PER_LONG; + return to_cpumask(p); +} + +#if NR_CPUS > 1 +/** + * num_online_cpus() - Read the number of online CPUs + * + * Despite the fact that __num_online_cpus is of type atomic_t, this + * interface gives only a momentary snapshot and is not protected against + * concurrent CPU hotplug operations unless invoked from a cpuhp_lock held + * region. + */ +static inline unsigned int num_online_cpus(void) +{ + return atomic_read(&__num_online_cpus); +} +#define num_possible_cpus() cpumask_weight(cpu_possible_mask) +#define num_present_cpus() cpumask_weight(cpu_present_mask) +#define num_active_cpus() cpumask_weight(cpu_active_mask) + +static inline bool cpu_online(unsigned int cpu) +{ + return cpumask_test_cpu(cpu, cpu_online_mask); +} + +static inline bool cpu_possible(unsigned int cpu) +{ + return cpumask_test_cpu(cpu, cpu_possible_mask); +} + +static inline bool cpu_present(unsigned int cpu) +{ + return cpumask_test_cpu(cpu, cpu_present_mask); +} + +static inline bool cpu_active(unsigned int cpu) +{ + return cpumask_test_cpu(cpu, cpu_active_mask); +} + +static inline bool cpu_dying(unsigned int cpu) +{ + return cpumask_test_cpu(cpu, cpu_dying_mask); +} + +#else + +#define num_online_cpus() 1U +#define num_possible_cpus() 1U +#define num_present_cpus() 1U +#define num_active_cpus() 1U + +static inline bool cpu_online(unsigned int cpu) +{ + return cpu == 0; +} + +static inline bool cpu_possible(unsigned int cpu) +{ + return cpu == 0; +} + +static inline bool cpu_present(unsigned int cpu) +{ + return cpu == 0; +} + +static inline bool cpu_active(unsigned int cpu) +{ + return cpu == 0; +} + +static inline bool cpu_dying(unsigned int cpu) +{ + return false; +} + +#endif /* NR_CPUS > 1 */ + +#define cpu_is_offline(cpu) unlikely(!cpu_online(cpu)) + +#if NR_CPUS <= BITS_PER_LONG +#define CPU_BITS_ALL \ +{ \ + [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(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] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ +} +#endif /* NR_CPUS > BITS_PER_LONG */ + +/** + * cpumap_print_to_pagebuf - copies the cpumask into the buffer either + * as comma-separated list of cpus or hex values of cpumask + * @list: indicates whether the cpumap must be list + * @mask: the cpumask to copy + * @buf: the buffer to copy into + * + * Returns the length of the (null-terminated) @buf string, zero if + * nothing is copied. + */ +static inline ssize_t +cpumap_print_to_pagebuf(bool list, char *buf, const struct cpumask *mask) +{ + return bitmap_print_to_pagebuf(list, buf, cpumask_bits(mask), + nr_cpu_ids); +} + +/** + * cpumap_print_bitmask_to_buf - copies the cpumask into the buffer as + * hex values of cpumask + * + * @buf: the buffer to copy into + * @mask: the cpumask to copy + * @off: in the string from which we are copying, we copy to @buf + * @count: the maximum number of bytes to print + * + * The function prints the cpumask into the buffer as hex values of + * cpumask; Typically used by bin_attribute to export cpumask bitmask + * ABI. + * + * Returns the length of how many bytes have been copied, excluding + * terminating '\0'. + */ +static inline ssize_t +cpumap_print_bitmask_to_buf(char *buf, const struct cpumask *mask, + loff_t off, size_t count) +{ + return bitmap_print_bitmask_to_buf(buf, cpumask_bits(mask), + nr_cpu_ids, off, count) - 1; +} + +/** + * cpumap_print_list_to_buf - copies the cpumask into the buffer as + * comma-separated list of cpus + * + * Everything is same with the above cpumap_print_bitmask_to_buf() + * except the print format. + */ +static inline ssize_t +cpumap_print_list_to_buf(char *buf, const struct cpumask *mask, + loff_t off, size_t count) +{ + return bitmap_print_list_to_buf(buf, cpumask_bits(mask), + nr_cpu_ids, off, count) - 1; +} + +#if NR_CPUS <= BITS_PER_LONG +#define CPU_MASK_ALL \ +(cpumask_t) { { \ + [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ +} } +#else +#define CPU_MASK_ALL \ +(cpumask_t) { { \ + [0 ... BITS_TO_LONGS(NR_CPUS)-2] = ~0UL, \ + [BITS_TO_LONGS(NR_CPUS)-1] = BITMAP_LAST_WORD_MASK(NR_CPUS) \ +} } +#endif /* NR_CPUS > BITS_PER_LONG */ + +#define CPU_MASK_NONE \ +(cpumask_t) { { \ + [0 ... BITS_TO_LONGS(NR_CPUS)-1] = 0UL \ +} } + +#define CPU_MASK_CPU0 \ +(cpumask_t) { { \ + [0] = 1UL \ +} } + +/* + * Provide a valid theoretical max size for cpumap and cpulist sysfs files + * to avoid breaking userspace which may allocate a buffer based on the size + * reported by e.g. fstat. + * + * for cpumap NR_CPUS * 9/32 - 1 should be an exact length. + * + * For cpulist 7 is (ceil(log10(NR_CPUS)) + 1) allowing for NR_CPUS to be up + * to 2 orders of magnitude larger than 8192. And then we divide by 2 to + * cover a worst-case of every other cpu being on one of two nodes for a + * very large NR_CPUS. + * + * Use PAGE_SIZE as a minimum for smaller configurations while avoiding + * unsigned comparison to -1. + */ +#define CPUMAP_FILE_MAX_BYTES (((NR_CPUS * 9)/32 > PAGE_SIZE) \ + ? (NR_CPUS * 9)/32 - 1 : PAGE_SIZE) +#define CPULIST_FILE_MAX_BYTES (((NR_CPUS * 7)/2 > PAGE_SIZE) ? (NR_CPUS * 7)/2 : PAGE_SIZE) + +#endif /* __LINUX_CPUMASK_H */ |