diff options
Diffstat (limited to 'include/linux/cpumask.h')
| -rw-r--r-- | include/linux/cpumask.h | 118 |
1 files changed, 92 insertions, 26 deletions
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h index bd047864c7ac..c2aa0aa26b45 100644 --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -35,19 +35,23 @@ typedef struct cpumask { DECLARE_BITMAP(bits, NR_CPUS); } cpumask_t; */ #define cpumask_pr_args(maskp) nr_cpu_ids, cpumask_bits(maskp) -#if NR_CPUS == 1 -#define nr_cpu_ids 1U +#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 -#ifdef CONFIG_CPUMASK_OFFSTACK -/* Assuming NR_CPUS is huge, a runtime limit is more efficient. Also, - * not all bits may be allocated. */ -#define nr_cpumask_bits nr_cpu_ids +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 -#define nr_cpumask_bits ((unsigned int)NR_CPUS) + 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 @@ -67,10 +71,6 @@ extern unsigned int nr_cpu_ids; * cpu_online_mask is the dynamic subset of cpu_present_mask, * indicating those CPUs available for scheduling. * - * If HOTPLUG is enabled, then cpu_possible_mask 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_mask varies dynamically, * depending on what ACPI reports as currently plugged in, otherwise * cpu_present_mask is just a copy of cpu_possible_mask. @@ -246,9 +246,7 @@ unsigned int cpumask_next_and(int n, const struct cpumask *src1p, * 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_set_bit(cpu, cpumask_bits(mask), nr_cpumask_bits) /** * for_each_cpu_not - iterate over every cpu in a complemented mask @@ -258,9 +256,7 @@ unsigned int cpumask_next_and(int n, const struct cpumask *src1p, * After the loop, cpu is >= nr_cpu_ids. */ #define for_each_cpu_not(cpu, mask) \ - for ((cpu) = -1; \ - (cpu) = cpumask_next_zero((cpu), (mask)), \ - (cpu) < nr_cpu_ids;) + for_each_clear_bit(cpu, cpumask_bits(mask), nr_cpumask_bits) #if NR_CPUS == 1 static inline @@ -293,10 +289,8 @@ unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int sta * * After the loop, cpu is >= nr_cpu_ids. */ -#define for_each_cpu_wrap(cpu, mask, start) \ - for ((cpu) = cpumask_next_wrap((start)-1, (mask), (start), false); \ - (cpu) < nr_cpumask_bits; \ - (cpu) = cpumask_next_wrap((cpu), (mask), (start), true)) +#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 @@ -313,9 +307,25 @@ unsigned int __pure cpumask_next_wrap(int n, const struct cpumask *mask, int sta * After the loop, cpu is >= nr_cpu_ids. */ #define for_each_cpu_and(cpu, mask1, mask2) \ - for ((cpu) = -1; \ - (cpu) = cpumask_next_and((cpu), (mask1), (mask2)), \ - (cpu) < nr_cpu_ids;) + 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. @@ -337,6 +347,50 @@ unsigned int cpumask_any_but(const struct cpumask *mask, unsigned int cpu) 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 \ @@ -587,6 +641,17 @@ static inline unsigned int cpumask_weight(const struct cpumask *srcp) } /** + * 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 @@ -1127,9 +1192,10 @@ cpumap_print_list_to_buf(char *buf, const struct cpumask *mask, * 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. + * Use PAGE_SIZE as a minimum for smaller configurations while avoiding + * unsigned comparison to -1. */ -#define CPUMAP_FILE_MAX_BYTES ((((NR_CPUS * 9)/32 - 1) > PAGE_SIZE) \ +#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) |