Commit e7bdd7f0 authored by Ming Lei's avatar Ming Lei Committed by Thomas Gleixner
Browse files

genirq/affinity: Don't pass irq_affinity_desc array to irq_build_affinity_masks 



Prepare for abstracting irq_build_affinity_masks() into a public function
for assigning all CPUs evenly into several groups.

Don't pass irq_affinity_desc array to irq_build_affinity_masks, instead
return a cpumask array by storing each assigned group into one element of
the array.

This allows to provide a generic interface for grouping all CPUs evenly
from a NUMA and CPU locality viewpoint, and the cost is one extra allocation
in irq_build_affinity_masks(), which should be fine since it is done via
GFP_KERNEL and irq_build_affinity_masks() is a slow path anyway.

Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJohn Garry <john.g.garry@oracle.com>
Reviewed-by: default avatarJens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/20221227022905.352674-4-ming.lei@redhat.com
parent 1f962d91

kernel/irq/affinity.c

+24 −10
Original line number Diff line number Diff line
@@ -249,7 +249,7 @@ static int __irq_build_affinity_masks(unsigned int startvec, 
				      cpumask_var_t *node_to_cpumask,

				      const struct cpumask *cpu_mask,

				      struct cpumask *nmsk,

				      struct irq_affinity_desc *masks)

				      struct cpumask *masks)

{

	unsigned int i, n, nodes, cpus_per_vec, extra_vecs, done = 0;

	unsigned int last_affv = numvecs;
@@ -270,7 +270,7 @@ static int __irq_build_affinity_masks(unsigned int startvec, 
		for_each_node_mask(n, nodemsk) {

			/* Ensure that only CPUs which are in both masks are set */

			cpumask_and(nmsk, cpu_mask, node_to_cpumask[n]);

			cpumask_or(&masks[curvec].mask, &masks[curvec].mask, nmsk);

			cpumask_or(&masks[curvec], &masks[curvec], nmsk);

			if (++curvec == last_affv)

				curvec = 0;

		}
@@ -321,7 +321,7 @@ static int __irq_build_affinity_masks(unsigned int startvec, 
			 */

			if (curvec >= last_affv)

				curvec = 0;

			irq_spread_init_one(&masks[curvec].mask, nmsk,

			irq_spread_init_one(&masks[curvec], nmsk,

						cpus_per_vec);

		}

		done += nv->nvectors;
@@ -335,16 +335,16 @@ static int __irq_build_affinity_masks(unsigned int startvec, 
 *	1) spread present CPU on these vectors

 *	2) spread other possible CPUs on these vectors

 */

static int irq_build_affinity_masks(unsigned int numvecs,

				    struct irq_affinity_desc *masks)

static struct cpumask *irq_build_affinity_masks(unsigned int numvecs)

{

	unsigned int curvec = 0, nr_present = 0, nr_others = 0;

	cpumask_var_t *node_to_cpumask;

	cpumask_var_t nmsk, npresmsk;

	int ret = -ENOMEM;

	struct cpumask *masks = NULL;



	if (!zalloc_cpumask_var(&nmsk, GFP_KERNEL))

		return ret;

		return NULL;



	if (!zalloc_cpumask_var(&npresmsk, GFP_KERNEL))

		goto fail_nmsk;
@@ -353,6 +353,10 @@ static int irq_build_affinity_masks(unsigned int numvecs, 
	if (!node_to_cpumask)

		goto fail_npresmsk;



	masks = kcalloc(numvecs, sizeof(*masks), GFP_KERNEL);

	if (!masks)

		goto fail_node_to_cpumask;



	/* Stabilize the cpumasks */

	cpus_read_lock();

	build_node_to_cpumask(node_to_cpumask);
@@ -386,6 +390,7 @@ static int irq_build_affinity_masks(unsigned int numvecs, 
	if (ret >= 0)

		WARN_ON(nr_present + nr_others < numvecs);



 fail_node_to_cpumask:

	free_node_to_cpumask(node_to_cpumask);



 fail_npresmsk:
@@ -393,7 +398,11 @@ static int irq_build_affinity_masks(unsigned int numvecs, 


 fail_nmsk:

	free_cpumask_var(nmsk);

	return ret < 0 ? ret : 0;

	if (ret < 0) {

		kfree(masks);

		return NULL;

	}

	return masks;

}



static void default_calc_sets(struct irq_affinity *affd, unsigned int affvecs)
@@ -457,13 +466,18 @@ irq_create_affinity_masks(unsigned int nvecs, struct irq_affinity *affd) 
	 */

	for (i = 0, usedvecs = 0; i < affd->nr_sets; i++) {

		unsigned int this_vecs = affd->set_size[i];

		int ret;

		int j;

		struct cpumask *result = irq_build_affinity_masks(this_vecs);



		ret = irq_build_affinity_masks(this_vecs, &masks[curvec]);

		if (ret) {

		if (!result) {

			kfree(masks);

			return NULL;

		}



		for (j = 0; j < this_vecs; j++)

			cpumask_copy(&masks[curvec + j].mask, &result[j]);

		kfree(result);



		curvec += this_vecs;

		usedvecs += this_vecs;

	}