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: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jens 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: Thomas Gleixner <tglx@linutronix.de>

diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index dad2da7cf80e42dfc98a5814cecc503f124a6329..f4a108b59336b39c35987ff4e4a4eeda274ceb07 100644 (file)
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -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");
        }

diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 9081f23bc0ff2d0623ddd65b1d06c50c0fb38cd2..53144e78a3691d2d0ea46b48319c5af337f0fda2 100644 (file)
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -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;
 }

diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
index 8d9259727cb42e667093dd02b16495087bc93a88..17360bd9619bd3aeef71f9888e68686eec92b74b 100644 (file)
--- a/kernel/irq/affinity.c
+++ b/kernel/irq/affinity.c
@@ -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;