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Diffstat (limited to 'kernel/irq/affinity.c')
-rw-r--r--kernel/irq/affinity.c227
1 files changed, 152 insertions, 75 deletions
diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
index f4f29b9d90ee..f18cd5aa33e8 100644
--- a/kernel/irq/affinity.c
+++ b/kernel/irq/affinity.c
@@ -9,7 +9,7 @@
#include <linux/cpu.h>
static void irq_spread_init_one(struct cpumask *irqmsk, struct cpumask *nmsk,
- int cpus_per_vec)
+ unsigned int cpus_per_vec)
{
const struct cpumask *siblmsk;
int cpu, sibl;
@@ -94,16 +94,18 @@ static int get_nodes_in_cpumask(cpumask_var_t *node_to_cpumask,
return nodes;
}
-static int irq_build_affinity_masks(const struct irq_affinity *affd,
- int startvec, int numvecs,
- cpumask_var_t *node_to_cpumask,
- const struct cpumask *cpu_mask,
- struct cpumask *nmsk,
- struct cpumask *masks)
+static int __irq_build_affinity_masks(const struct irq_affinity *affd,
+ unsigned int startvec,
+ unsigned int numvecs,
+ unsigned int firstvec,
+ cpumask_var_t *node_to_cpumask,
+ const struct cpumask *cpu_mask,
+ struct cpumask *nmsk,
+ struct irq_affinity_desc *masks)
{
- int n, nodes, cpus_per_vec, extra_vecs, done = 0;
- int last_affv = affd->pre_vectors + numvecs;
- int curvec = startvec;
+ unsigned int n, nodes, cpus_per_vec, extra_vecs, done = 0;
+ unsigned int last_affv = firstvec + numvecs;
+ unsigned int curvec = startvec;
nodemask_t nodemsk = NODE_MASK_NONE;
if (!cpumask_weight(cpu_mask))
@@ -117,20 +119,19 @@ static int irq_build_affinity_masks(const struct irq_affinity *affd,
*/
if (numvecs <= nodes) {
for_each_node_mask(n, nodemsk) {
- cpumask_copy(masks + curvec, node_to_cpumask[n]);
- if (++done == numvecs)
- break;
+ cpumask_or(&masks[curvec].mask, &masks[curvec].mask,
+ node_to_cpumask[n]);
if (++curvec == last_affv)
- curvec = affd->pre_vectors;
+ curvec = firstvec;
}
- goto out;
+ return numvecs;
}
for_each_node_mask(n, nodemsk) {
- int ncpus, v, vecs_to_assign, vecs_per_node;
+ unsigned int ncpus, v, vecs_to_assign, vecs_per_node;
/* Spread the vectors per node */
- vecs_per_node = (numvecs - (curvec - affd->pre_vectors)) / nodes;
+ vecs_per_node = (numvecs - (curvec - firstvec)) / nodes;
/* Get the cpus on this node which are in the mask */
cpumask_and(nmsk, cpu_mask, node_to_cpumask[n]);
@@ -151,69 +152,54 @@ static int irq_build_affinity_masks(const struct irq_affinity *affd,
cpus_per_vec++;
--extra_vecs;
}
- irq_spread_init_one(masks + curvec, nmsk, cpus_per_vec);
+ irq_spread_init_one(&masks[curvec].mask, nmsk,
+ cpus_per_vec);
}
done += v;
if (done >= numvecs)
break;
if (curvec >= last_affv)
- curvec = affd->pre_vectors;
+ curvec = firstvec;
--nodes;
}
-
-out:
return done;
}
-/**
- * irq_create_affinity_masks - Create affinity masks for multiqueue spreading
- * @nvecs: The total number of vectors
- * @affd: Description of the affinity requirements
- *
- * Returns the masks pointer or NULL if allocation failed.
+/*
+ * build affinity in two stages:
+ * 1) spread present CPU on these vectors
+ * 2) spread other possible CPUs on these vectors
*/
-struct cpumask *
-irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd)
+static int irq_build_affinity_masks(const struct irq_affinity *affd,
+ unsigned int startvec, unsigned int numvecs,
+ unsigned int firstvec,
+ struct irq_affinity_desc *masks)
{
- int affvecs = nvecs - affd->pre_vectors - affd->post_vectors;
- int curvec, usedvecs;
- cpumask_var_t nmsk, npresmsk, *node_to_cpumask;
- struct cpumask *masks = NULL;
-
- /*
- * If there aren't any vectors left after applying the pre/post
- * vectors don't bother with assigning affinity.
- */
- if (nvecs == affd->pre_vectors + affd->post_vectors)
- return NULL;
+ unsigned int curvec = startvec, nr_present, nr_others;
+ cpumask_var_t *node_to_cpumask;
+ cpumask_var_t nmsk, npresmsk;
+ int ret = -ENOMEM;
if (!zalloc_cpumask_var(&nmsk, GFP_KERNEL))
- return NULL;
+ return ret;
if (!zalloc_cpumask_var(&npresmsk, GFP_KERNEL))
- goto outcpumsk;
+ goto fail_nmsk;
node_to_cpumask = alloc_node_to_cpumask();
if (!node_to_cpumask)
- goto outnpresmsk;
-
- masks = kcalloc(nvecs, sizeof(*masks), GFP_KERNEL);
- if (!masks)
- goto outnodemsk;
-
- /* Fill out vectors at the beginning that don't need affinity */
- for (curvec = 0; curvec < affd->pre_vectors; curvec++)
- cpumask_copy(masks + curvec, irq_default_affinity);
+ goto fail_npresmsk;
+ ret = 0;
/* Stabilize the cpumasks */
get_online_cpus();
build_node_to_cpumask(node_to_cpumask);
/* Spread on present CPUs starting from affd->pre_vectors */
- usedvecs = irq_build_affinity_masks(affd, curvec, affvecs,
- node_to_cpumask, cpu_present_mask,
- nmsk, masks);
+ nr_present = __irq_build_affinity_masks(affd, curvec, numvecs,
+ firstvec, node_to_cpumask,
+ cpu_present_mask, nmsk, masks);
/*
* Spread on non present CPUs starting from the next vector to be
@@ -221,30 +207,116 @@ irq_create_affinity_masks(int nvecs, const struct irq_affinity *affd)
* vector space, assign the non present CPUs to the already spread
* out vectors.
*/
- if (usedvecs >= affvecs)
- curvec = affd->pre_vectors;
+ if (nr_present >= numvecs)
+ curvec = firstvec;
else
- curvec = affd->pre_vectors + usedvecs;
+ curvec = firstvec + nr_present;
cpumask_andnot(npresmsk, cpu_possible_mask, cpu_present_mask);
- usedvecs += irq_build_affinity_masks(affd, curvec, affvecs,
- node_to_cpumask, npresmsk,
- nmsk, masks);
+ nr_others = __irq_build_affinity_masks(affd, curvec, numvecs,
+ firstvec, node_to_cpumask,
+ npresmsk, nmsk, masks);
put_online_cpus();
+ if (nr_present < numvecs)
+ WARN_ON(nr_present + nr_others < numvecs);
+
+ free_node_to_cpumask(node_to_cpumask);
+
+ fail_npresmsk:
+ free_cpumask_var(npresmsk);
+
+ fail_nmsk:
+ free_cpumask_var(nmsk);
+ return ret;
+}
+
+static void default_calc_sets(struct irq_affinity *affd, unsigned int affvecs)
+{
+ affd->nr_sets = 1;
+ affd->set_size[0] = affvecs;
+}
+
+/**
+ * irq_create_affinity_masks - Create affinity masks for multiqueue spreading
+ * @nvecs: The total number of vectors
+ * @affd: Description of the affinity requirements
+ *
+ * Returns the irq_affinity_desc pointer or NULL if allocation failed.
+ */
+struct irq_affinity_desc *
+irq_create_affinity_masks(unsigned int nvecs, struct irq_affinity *affd)
+{
+ unsigned int affvecs, curvec, usedvecs, i;
+ struct irq_affinity_desc *masks = NULL;
+
+ /*
+ * Determine the number of vectors which need interrupt affinities
+ * assigned. If the pre/post request exhausts the available vectors
+ * then nothing to do here except for invoking the calc_sets()
+ * callback so the device driver can adjust to the situation. If there
+ * is only a single vector, then managing the queue is pointless as
+ * well.
+ */
+ if (nvecs > 1 && nvecs > affd->pre_vectors + affd->post_vectors)
+ affvecs = nvecs - affd->pre_vectors - affd->post_vectors;
+ else
+ affvecs = 0;
+
+ /*
+ * Simple invocations do not provide a calc_sets() callback. Install
+ * the generic one.
+ */
+ if (!affd->calc_sets)
+ affd->calc_sets = default_calc_sets;
+
+ /* Recalculate the sets */
+ affd->calc_sets(affd, affvecs);
+
+ if (WARN_ON_ONCE(affd->nr_sets > IRQ_AFFINITY_MAX_SETS))
+ return NULL;
+
+ /* Nothing to assign? */
+ if (!affvecs)
+ return NULL;
+
+ masks = kcalloc(nvecs, sizeof(*masks), GFP_KERNEL);
+ if (!masks)
+ return NULL;
+
+ /* Fill out vectors at the beginning that don't need affinity */
+ for (curvec = 0; curvec < affd->pre_vectors; curvec++)
+ cpumask_copy(&masks[curvec].mask, irq_default_affinity);
+
+ /*
+ * Spread on present CPUs starting from affd->pre_vectors. If we
+ * have multiple sets, build each sets affinity mask separately.
+ */
+ for (i = 0, usedvecs = 0; i < affd->nr_sets; i++) {
+ unsigned int this_vecs = affd->set_size[i];
+ int ret;
+
+ ret = irq_build_affinity_masks(affd, curvec, this_vecs,
+ curvec, masks);
+ if (ret) {
+ kfree(masks);
+ return NULL;
+ }
+ curvec += this_vecs;
+ usedvecs += this_vecs;
+ }
+
/* Fill out vectors at the end that don't need affinity */
if (usedvecs >= affvecs)
curvec = affd->pre_vectors + affvecs;
else
curvec = affd->pre_vectors + usedvecs;
for (; curvec < nvecs; curvec++)
- cpumask_copy(masks + curvec, irq_default_affinity);
+ cpumask_copy(&masks[curvec].mask, irq_default_affinity);
+
+ /* Mark the managed interrupts */
+ for (i = affd->pre_vectors; i < nvecs - affd->post_vectors; i++)
+ masks[i].is_managed = 1;
-outnodemsk:
- free_node_to_cpumask(node_to_cpumask);
-outnpresmsk:
- free_cpumask_var(npresmsk);
-outcpumsk:
- free_cpumask_var(nmsk);
return masks;
}
@@ -254,17 +326,22 @@ outcpumsk:
* @maxvec: The maximum number of vectors available
* @affd: Description of the affinity requirements
*/
-int irq_calc_affinity_vectors(int minvec, int maxvec, const struct irq_affinity *affd)
+unsigned int irq_calc_affinity_vectors(unsigned int minvec, unsigned int maxvec,
+ const struct irq_affinity *affd)
{
- int resv = affd->pre_vectors + affd->post_vectors;
- int vecs = maxvec - resv;
- int ret;
+ unsigned int resv = affd->pre_vectors + affd->post_vectors;
+ unsigned int set_vecs;
if (resv > minvec)
return 0;
- get_online_cpus();
- ret = min_t(int, cpumask_weight(cpu_possible_mask), vecs) + resv;
- put_online_cpus();
- return ret;
+ if (affd->calc_sets) {
+ set_vecs = maxvec - resv;
+ } else {
+ get_online_cpus();
+ set_vecs = cpumask_weight(cpu_possible_mask);
+ put_online_cpus();
+ }
+
+ return resv + min(set_vecs, maxvec - resv);
}