Commit 16e2707c authored by Yury Norov [NVIDIA]'s avatar Yury Norov [NVIDIA] Committed by Leon Romanovsky
Browse files

cpumask: add cpumask_clear_cpus() 



When user wants to clear a range in cpumask, the only option the API
provides now is a for-loop, like:

	for_each_cpu_from(cpu, mask) {
		if (cpu >= ncpus)
			break;
		__cpumask_clear_cpu(cpu, mask);
	}

In the bitmap API we have bitmap_clear() for that, which is
significantly faster than a for-loop. Propagate it to cpumasks.

Signed-off-by: default avatarYury Norov [NVIDIA] <yury.norov@gmail.com>
Link: https://patch.msgid.link/20250604193947.11834-2-yury.norov@gmail.com


Signed-off-by: default avatarLeon Romanovsky <leon@kernel.org>
parent 43163f4c

include/linux/cpumask.h

+12 −0
Original line number Diff line number Diff line
@@ -609,6 +609,18 @@ void __cpumask_set_cpu(unsigned int cpu, struct cpumask *dstp) 
	__set_bit(cpumask_check(cpu), cpumask_bits(dstp));

}



/**

 * cpumask_clear_cpus - clear cpus in a cpumask

 * @dstp:  the cpumask pointer

 * @cpu:   cpu number (< nr_cpu_ids)

 * @ncpus: number of cpus to clear (< nr_cpu_ids)

 */

static __always_inline void cpumask_clear_cpus(struct cpumask *dstp,

						unsigned int cpu, unsigned int ncpus)

{

	cpumask_check(cpu + ncpus - 1);

	bitmap_clear(cpumask_bits(dstp), cpumask_check(cpu), ncpus);

}



/**

 * cpumask_clear_cpu - clear a cpu in a cpumask