@@ -279,6 +279,8 @@ extern int
irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);
struct cpumask *irq_create_affinity_mask(unsigned int *nr_vecs);
+struct cpumask *irq_create_affinity_masks(const struct cpumask *affinity, int nvec);
+int irq_calc_affinity_vectors(const struct cpumask *affinity, int maxvec);
#else /* CONFIG_SMP */
@@ -316,6 +318,19 @@ static inline struct cpumask *irq_create_affinity_mask(unsigned int *nr_vecs)
*nr_vecs = 1;
return NULL;
}
+
+static inline struct cpumask *
+irq_create_affinity_masks(const struct cpumask *affinity, int nvec)
+{
+ return NULL;
+}
+
+static inline int
+irq_calc_affinity_vectors(const struct cpumask *affinity, int maxvec)
+{
+ return maxvec;
+}
+
#endif /* CONFIG_SMP */
/*
@@ -4,6 +4,155 @@
#include <linux/slab.h>
#include <linux/cpu.h>
+static void irq_spread_init_one(struct cpumask *irqmsk, struct cpumask *nmsk,
+ int cpus_per_vec)
+{
+ const struct cpumask *siblmsk;
+ int cpu, sibl;
+
+ for ( ; cpus_per_vec > 0; ) {
+ cpu = cpumask_first(nmsk);
+
+ /* Should not happen, but I'm too lazy to think about it */
+ if (cpu >= nr_cpu_ids)
+ return;
+
+ cpumask_clear_cpu(cpu, nmsk);
+ cpumask_set_cpu(cpu, irqmsk);
+ cpus_per_vec--;
+
+ /* If the cpu has siblings, use them first */
+ siblmsk = topology_sibling_cpumask(cpu);
+ for (sibl = -1; cpus_per_vec > 0; ) {
+ sibl = cpumask_next(sibl, siblmsk);
+ if (sibl >= nr_cpu_ids)
+ break;
+ if (!cpumask_test_and_clear_cpu(sibl, nmsk))
+ continue;
+ cpumask_set_cpu(sibl, irqmsk);
+ cpus_per_vec--;
+ }
+ }
+}
+
+static int get_nodes_in_cpumask(const struct cpumask *mask, nodemask_t *nodemsk)
+{
+ int n, nodes;
+
+ /* Calculate the number of nodes in the supplied affinity mask */
+ for (n = 0, nodes = 0; n < num_online_nodes(); n++) {
+ if (cpumask_intersects(mask, cpumask_of_node(n))) {
+ node_set(n, *nodemsk);
+ nodes++;
+ }
+ }
+ return nodes;
+}
+
+/**
+ * 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
+ *
+ * Returns the masks pointer or NULL if allocation failed.
+ */
+struct cpumask *irq_create_affinity_masks(const struct cpumask *affinity,
+ int nvec)
+{
+ int n, nodes, vecs_per_node, cpus_per_vec, extra_vecs, curvec = 0;
+ nodemask_t nodemsk = NODE_MASK_NONE;
+ struct cpumask *masks;
+ cpumask_var_t nmsk;
+
+ if (!zalloc_cpumask_var(&nmsk, GFP_KERNEL))
+ return NULL;
+
+ masks = kzalloc(nvec * sizeof(*masks), GFP_KERNEL);
+ if (!masks)
+ goto out;
+
+ /* 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);
+
+ /*
+ * 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) {
+ for_each_node_mask(n, nodemsk) {
+ cpumask_copy(masks + curvec, cpumask_of_node(n));
+ if (++curvec == nvec)
+ break;
+ }
+ goto outonl;
+ }
+
+ /* Spread the vectors per node */
+ vecs_per_node = nvec / nodes;
+ /* Account for rounding errors */
+ extra_vecs = nvec - (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));
+
+ /* Calculate the number of cpus per vector */
+ ncpus = cpumask_weight(nmsk);
+
+ for (v = 0; curvec < nvec && v < vecs_to_assign; curvec++, v++) {
+ cpus_per_vec = ncpus / vecs_to_assign;
+
+ /* Account for extra vectors to compensate rounding errors */
+ if (extra_vecs) {
+ cpus_per_vec++;
+ if (!--extra_vecs)
+ vecs_per_node++;
+ }
+ irq_spread_init_one(masks + curvec, nmsk, cpus_per_vec);
+ }
+
+ if (curvec >= nvec)
+ break;
+ }
+
+outonl:
+ put_online_cpus();
+out:
+ free_cpumask_var(nmsk);
+ return masks;
+}
+
+/**
+ * irq_calc_affinity_vectors - Calculate to optimal number of vectors for a given affinity mask
+ * @affinity: The affinity mask to spread. If NULL cpu_online_mask
+ * is used
+ * @maxvec: The maximum number of vectors available
+ */
+int irq_calc_affinity_vectors(const struct cpumask *affinity, int maxvec)
+{
+ int cpus, ret;
+
+ /* Stabilize the cpumasks */
+ get_online_cpus();
+ /* If the supplied affinity mask is NULL, use cpu online mask */
+ if (!affinity)
+ affinity = cpu_online_mask;
+
+ cpus = cpumask_weight(affinity);
+ ret = (cpus < maxvec) ? cpus : maxvec;
+
+ put_online_cpus();
+ return ret;
+}
+
static int get_first_sibling(unsigned int cpu)
{
unsigned int ret;