Commit 67c93c21 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Thomas Gleixner
Browse files

genirq/affinity: Handle pre/post vectors in irq_create_affinity_masks() 



Only calculate the affinity for the main I/O vectors, and skip the
pre or post vectors specified by struct irq_affinity.

Also remove the irq_affinity cpumask argument that has never been used.
If we ever need it in the future we can pass it through struct
irq_affinity.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarHannes Reinecke <hare@suse.com>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Acked-by: default avatarJens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/1478654107-7384-4-git-send-email-hch@lst.de


Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 212bd846

drivers/pci/msi.c

+4 −2
Original line number Diff line number Diff line
@@ -553,12 +553,13 @@ error_attrs: 
static struct msi_desc *

msi_setup_entry(struct pci_dev *dev, int nvec, bool affinity)

{

	static const struct irq_affinity default_affd;

	struct cpumask *masks = NULL;

	struct msi_desc *entry;

	u16 control;



	if (affinity) {

		masks = irq_create_affinity_masks(dev->irq_affinity, nvec);

		masks = irq_create_affinity_masks(nvec, &default_affd);

		if (!masks)

			pr_err("Unable to allocate affinity masks, ignoring\n");

	}
@@ -692,12 +693,13 @@ static int msix_setup_entries(struct pci_dev *dev, void __iomem *base, 
			      struct msix_entry *entries, int nvec,

			      bool affinity)

{

	static const struct irq_affinity default_affd;

	struct cpumask *curmsk, *masks = NULL;

	struct msi_desc *entry;

	int ret, i;



	if (affinity) {

		masks = irq_create_affinity_masks(dev->irq_affinity, nvec);

		masks = irq_create_affinity_masks(nvec, &default_affd);

		if (!masks)

			pr_err("Unable to allocate affinity masks, ignoring\n");

	}

include/linux/interrupt.h

+2 −2
Original line number Diff line number Diff line
@@ -290,7 +290,7 @@ extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m); 
extern int

irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);



struct cpumask *irq_create_affinity_masks(const struct cpumask *affinity, int nvec);

struct cpumask *irq_create_affinity_masks(int nvec, const struct irq_affinity *affd);

int irq_calc_affinity_vectors(int maxvec, const struct irq_affinity *affd);



#else /* CONFIG_SMP */
@@ -325,7 +325,7 @@ irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify) 
}



static inline struct cpumask *

irq_create_affinity_masks(const struct cpumask *affinity, int nvec)

irq_create_affinity_masks(int nvec, const struct irq_affinity *affd)

{

	return NULL;

}

kernel/irq/affinity.c

+25 −21
Original line number Diff line number Diff line
@@ -51,16 +51,16 @@ static int get_nodes_in_cpumask(const struct cpumask *mask, nodemask_t *nodemsk) 


/**

 * irq_create_affinity_masks - Create affinity masks for multiqueue spreading

 * @affinity:		The affinity mask to spread. If NULL cpu_online_mask

 *			is used

 * @nvecs:		The number of vectors

 * @nvecs:	The total number of vectors

 * @affd:	Description of the affinity requirements

 *

 * Returns the masks pointer or NULL if allocation failed.

 */

struct cpumask *irq_create_affinity_masks(const struct cpumask *affinity,

					  int nvec)

struct cpumask *

irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd)

{

	int n, nodes, vecs_per_node, cpus_per_vec, extra_vecs, curvec = 0;

	int n, nodes, vecs_per_node, cpus_per_vec, extra_vecs, curvec;

	int affv = nvecs - affd->pre_vectors - affd->post_vectors;

	nodemask_t nodemsk = NODE_MASK_NONE;

	struct cpumask *masks;

	cpumask_var_t nmsk;
@@ -68,46 +68,46 @@ struct cpumask *irq_create_affinity_masks(const struct cpumask *affinity, 
	if (!zalloc_cpumask_var(&nmsk, GFP_KERNEL))

		return NULL;



	masks = kzalloc(nvec * sizeof(*masks), GFP_KERNEL);

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

	if (!masks)

		goto out;



	/* Fill out vectors at the beginning that don't need affinity */

	for (curvec = 0; curvec < affd->pre_vectors; curvec++)

		cpumask_copy(masks + curvec, cpu_possible_mask);



	/* Stabilize the cpumasks */

	get_online_cpus();

	/* If the supplied affinity mask is NULL, use cpu online mask */

	if (!affinity)

		affinity = cpu_online_mask;



	nodes = get_nodes_in_cpumask(affinity, &nodemsk);

	nodes = get_nodes_in_cpumask(cpu_online_mask, &nodemsk);



	/*

	 * If the number of nodes in the mask is less than or equal the

	 * number of vectors we just spread the vectors across the nodes.

	 */

	if (nvec <= nodes) {

	if (affv <= nodes) {

		for_each_node_mask(n, nodemsk) {

			cpumask_copy(masks + curvec, cpumask_of_node(n));

			if (++curvec == nvec)

			if (++curvec == affv)

				break;

		}

		goto outonl;

		goto done;

	}



	/* Spread the vectors per node */

	vecs_per_node = nvec / nodes;

	vecs_per_node = affv / nodes;

	/* Account for rounding errors */

	extra_vecs = nvec - (nodes * vecs_per_node);

	extra_vecs = affv - (nodes * vecs_per_node);



	for_each_node_mask(n, nodemsk) {

		int ncpus, v, vecs_to_assign = vecs_per_node;



		/* Get the cpus on this node which are in the mask */

		cpumask_and(nmsk, affinity, cpumask_of_node(n));

		cpumask_and(nmsk, cpu_online_mask, cpumask_of_node(n));



		/* Calculate the number of cpus per vector */

		ncpus = cpumask_weight(nmsk);



		for (v = 0; curvec < nvec && v < vecs_to_assign; curvec++, v++) {

		for (v = 0; curvec < affv && v < vecs_to_assign; curvec++, v++) {

			cpus_per_vec = ncpus / vecs_to_assign;



			/* Account for extra vectors to compensate rounding errors */
@@ -119,12 +119,16 @@ struct cpumask *irq_create_affinity_masks(const struct cpumask *affinity, 
			irq_spread_init_one(masks + curvec, nmsk, cpus_per_vec);

		}



		if (curvec >= nvec)

		if (curvec >= affv)

			break;

	}



outonl:

done:

	put_online_cpus();



	/* Fill out vectors at the end that don't need affinity */

	for (; curvec < nvecs; curvec++)

		cpumask_copy(masks + curvec, cpu_possible_mask);

out:

	free_cpumask_var(nmsk);

	return masks;

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