1 files changed, 9 insertions, 396 deletions

diff --git a/kernel/irq/affinity.c b/kernel/irq/affinity.c
index d9a5c1d65a79..44a4eba80315 100644
--- a/kernel/irq/affinity.c
+++ b/kernel/irq/affinity.c
@@ -7,398 +7,7 @@
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/cpu.h>
-#include <linux/sort.h>
-
-static void irq_spread_init_one(struct cpumask *irqmsk, struct cpumask *nmsk,
-				unsigned 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 cpumask_var_t *alloc_node_to_cpumask(void)
-{
-	cpumask_var_t *masks;
-	int node;
-
-	masks = kcalloc(nr_node_ids, sizeof(cpumask_var_t), GFP_KERNEL);
-	if (!masks)
-		return NULL;
-
-	for (node = 0; node < nr_node_ids; node++) {
-		if (!zalloc_cpumask_var(&masks[node], GFP_KERNEL))
-			goto out_unwind;
-	}
-
-	return masks;
-
-out_unwind:
-	while (--node >= 0)
-		free_cpumask_var(masks[node]);
-	kfree(masks);
-	return NULL;
-}
-
-static void free_node_to_cpumask(cpumask_var_t *masks)
-{
-	int node;
-
-	for (node = 0; node < nr_node_ids; node++)
-		free_cpumask_var(masks[node]);
-	kfree(masks);
-}
-
-static void build_node_to_cpumask(cpumask_var_t *masks)
-{
-	int cpu;
-
-	for_each_possible_cpu(cpu)
-		cpumask_set_cpu(cpu, masks[cpu_to_node(cpu)]);
-}
-
-static int get_nodes_in_cpumask(cpumask_var_t *node_to_cpumask,
-				const struct cpumask *mask, nodemask_t *nodemsk)
-{
-	int n, nodes = 0;
-
-	/* Calculate the number of nodes in the supplied affinity mask */
-	for_each_node(n) {
-		if (cpumask_intersects(mask, node_to_cpumask[n])) {
-			node_set(n, *nodemsk);
-			nodes++;
-		}
-	}
-	return nodes;
-}
-
-struct node_vectors {
-	unsigned id;
-
-	union {
-		unsigned nvectors;
-		unsigned ncpus;
-	};
-};
-
-static int ncpus_cmp_func(const void *l, const void *r)
-{
-	const struct node_vectors *ln = l;
-	const struct node_vectors *rn = r;
-
-	return ln->ncpus - rn->ncpus;
-}
-
-/*
- * Allocate vector number for each node, so that for each node:
- *
- * 1) the allocated number is >= 1
- *
- * 2) the allocated numbver is <= active CPU number of this node
- *
- * The actual allocated total vectors may be less than @numvecs when
- * active total CPU number is less than @numvecs.
- *
- * Active CPUs means the CPUs in '@cpu_mask AND @node_to_cpumask[]'
- * for each node.
- */
-static void alloc_nodes_vectors(unsigned int numvecs,
-				cpumask_var_t *node_to_cpumask,
-				const struct cpumask *cpu_mask,
-				const nodemask_t nodemsk,
-				struct cpumask *nmsk,
-				struct node_vectors *node_vectors)
-{
-	unsigned n, remaining_ncpus = 0;
-
-	for (n = 0; n < nr_node_ids; n++) {
-		node_vectors[n].id = n;
-		node_vectors[n].ncpus = UINT_MAX;
-	}
-
-	for_each_node_mask(n, nodemsk) {
-		unsigned ncpus;
-
-		cpumask_and(nmsk, cpu_mask, node_to_cpumask[n]);
-		ncpus = cpumask_weight(nmsk);
-
-		if (!ncpus)
-			continue;
-		remaining_ncpus += ncpus;
-		node_vectors[n].ncpus = ncpus;
-	}
-
-	numvecs = min_t(unsigned, remaining_ncpus, numvecs);
-
-	sort(node_vectors, nr_node_ids, sizeof(node_vectors[0]),
-	     ncpus_cmp_func, NULL);
-
-	/*
-	 * Allocate vectors for each node according to the ratio of this
-	 * node's nr_cpus to remaining un-assigned ncpus. 'numvecs' is
-	 * bigger than number of active numa nodes. Always start the
-	 * allocation from the node with minimized nr_cpus.
-	 *
-	 * This way guarantees that each active node gets allocated at
-	 * least one vector, and the theory is simple: over-allocation
-	 * is only done when this node is assigned by one vector, so
-	 * other nodes will be allocated >= 1 vector, since 'numvecs' is
-	 * bigger than number of numa nodes.
-	 *
-	 * One perfect invariant is that number of allocated vectors for
-	 * each node is <= CPU count of this node:
-	 *
-	 * 1) suppose there are two nodes: A and B
-	 * 	ncpu(X) is CPU count of node X
-	 * 	vecs(X) is the vector count allocated to node X via this
-	 * 	algorithm
-	 *
-	 * 	ncpu(A) <= ncpu(B)
-	 * 	ncpu(A) + ncpu(B) = N
-	 * 	vecs(A) + vecs(B) = V
-	 *
-	 * 	vecs(A) = max(1, round_down(V * ncpu(A) / N))
-	 * 	vecs(B) = V - vecs(A)
-	 *
-	 * 	both N and V are integer, and 2 <= V <= N, suppose
-	 * 	V = N - delta, and 0 <= delta <= N - 2
-	 *
-	 * 2) obviously vecs(A) <= ncpu(A) because:
-	 *
-	 * 	if vecs(A) is 1, then vecs(A) <= ncpu(A) given
-	 * 	ncpu(A) >= 1
-	 *
-	 * 	otherwise,
-	 * 		vecs(A) <= V * ncpu(A) / N <= ncpu(A), given V <= N
-	 *
-	 * 3) prove how vecs(B) <= ncpu(B):
-	 *
-	 * 	if round_down(V * ncpu(A) / N) == 0, vecs(B) won't be
-	 * 	over-allocated, so vecs(B) <= ncpu(B),
-	 *
-	 * 	otherwise:
-	 *
-	 * 	vecs(A) =
-	 * 		round_down(V * ncpu(A) / N) =
-	 * 		round_down((N - delta) * ncpu(A) / N) =
-	 * 		round_down((N * ncpu(A) - delta * ncpu(A)) / N)	 >=
-	 * 		round_down((N * ncpu(A) - delta * N) / N)	 =
-	 * 		cpu(A) - delta
-	 *
-	 * 	then:
-	 *
-	 * 	vecs(A) - V >= ncpu(A) - delta - V
-	 * 	=>
-	 * 	V - vecs(A) <= V + delta - ncpu(A)
-	 * 	=>
-	 * 	vecs(B) <= N - ncpu(A)
-	 * 	=>
-	 * 	vecs(B) <= cpu(B)
-	 *
-	 * For nodes >= 3, it can be thought as one node and another big
-	 * node given that is exactly what this algorithm is implemented,
-	 * and we always re-calculate 'remaining_ncpus' & 'numvecs', and
-	 * finally for each node X: vecs(X) <= ncpu(X).
-	 *
-	 */
-	for (n = 0; n < nr_node_ids; n++) {
-		unsigned nvectors, ncpus;
-
-		if (node_vectors[n].ncpus == UINT_MAX)
-			continue;
-
-		WARN_ON_ONCE(numvecs == 0);
-
-		ncpus = node_vectors[n].ncpus;
-		nvectors = max_t(unsigned, 1,
-				 numvecs * ncpus / remaining_ncpus);
-		WARN_ON_ONCE(nvectors > ncpus);
-
-		node_vectors[n].nvectors = nvectors;
-
-		remaining_ncpus -= ncpus;
-		numvecs -= nvectors;
-	}
-}
-
-static int __irq_build_affinity_masks(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)
-{
-	unsigned int i, 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;
-	struct node_vectors *node_vectors;
-
-	if (cpumask_empty(cpu_mask))
-		return 0;
-
-	nodes = get_nodes_in_cpumask(node_to_cpumask, cpu_mask, &nodemsk);
-
-	/*
-	 * If the number of nodes in the mask is greater than or equal the
-	 * number of vectors we just spread the vectors across the nodes.
-	 */
-	if (numvecs <= nodes) {
-		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);
-			if (++curvec == last_affv)
-				curvec = firstvec;
-		}
-		return numvecs;
-	}
-
-	node_vectors = kcalloc(nr_node_ids,
-			       sizeof(struct node_vectors),
-			       GFP_KERNEL);
-	if (!node_vectors)
-		return -ENOMEM;
-
-	/* allocate vector number for each node */
-	alloc_nodes_vectors(numvecs, node_to_cpumask, cpu_mask,
-			    nodemsk, nmsk, node_vectors);
-
-	for (i = 0; i < nr_node_ids; i++) {
-		unsigned int ncpus, v;
-		struct node_vectors *nv = &node_vectors[i];
-
-		if (nv->nvectors == UINT_MAX)
-			continue;
-
-		/* Get the cpus on this node which are in the mask */
-		cpumask_and(nmsk, cpu_mask, node_to_cpumask[nv->id]);
-		ncpus = cpumask_weight(nmsk);
-		if (!ncpus)
-			continue;
-
-		WARN_ON_ONCE(nv->nvectors > ncpus);
-
-		/* Account for rounding errors */
-		extra_vecs = ncpus - nv->nvectors * (ncpus / nv->nvectors);
-
-		/* Spread allocated vectors on CPUs of the current node */
-		for (v = 0; v < nv->nvectors; v++, curvec++) {
-			cpus_per_vec = ncpus / nv->nvectors;
-
-			/* Account for extra vectors to compensate rounding errors */
-			if (extra_vecs) {
-				cpus_per_vec++;
-				--extra_vecs;
-			}
-
-			/*
-			 * wrapping has to be considered given 'startvec'
-			 * may start anywhere
-			 */
-			if (curvec >= last_affv)
-				curvec = firstvec;
-			irq_spread_init_one(&masks[curvec].mask, nmsk,
-						cpus_per_vec);
-		}
-		done += nv->nvectors;
-	}
-	kfree(node_vectors);
-	return done;
-}
-
-/*
- * build affinity in two stages:
- *	1) spread present CPU on these vectors
- *	2) spread other possible CPUs on these vectors
- */
-static int irq_build_affinity_masks(unsigned int startvec, unsigned int numvecs,
-				    unsigned int firstvec,
-				    struct irq_affinity_desc *masks)
-{
-	unsigned int curvec = startvec, nr_present = 0, nr_others = 0;
-	cpumask_var_t *node_to_cpumask;
-	cpumask_var_t nmsk, npresmsk;
-	int ret = -ENOMEM;
-
-	if (!zalloc_cpumask_var(&nmsk, GFP_KERNEL))
-		return ret;
-
-	if (!zalloc_cpumask_var(&npresmsk, GFP_KERNEL))
-		goto fail_nmsk;
-
-	node_to_cpumask = alloc_node_to_cpumask();
-	if (!node_to_cpumask)
-		goto fail_npresmsk;
-
-	/* Stabilize the cpumasks */
-	cpus_read_lock();
-	build_node_to_cpumask(node_to_cpumask);
-
-	/* Spread on present CPUs starting from affd->pre_vectors */
-	ret = __irq_build_affinity_masks(curvec, numvecs, firstvec,
-					 node_to_cpumask, cpu_present_mask,
-					 nmsk, masks);
-	if (ret < 0)
-		goto fail_build_affinity;
-	nr_present = ret;
-
-	/*
-	 * Spread on non present CPUs starting from the next vector to be
-	 * handled. If the spreading of present CPUs already exhausted the
-	 * vector space, assign the non present CPUs to the already spread
-	 * out vectors.
-	 */
-	if (nr_present >= numvecs)
-		curvec = firstvec;
-	else
-		curvec = firstvec + nr_present;
-	cpumask_andnot(npresmsk, cpu_possible_mask, cpu_present_mask);
-	ret = __irq_build_affinity_masks(curvec, numvecs, firstvec,
-					 node_to_cpumask, npresmsk, nmsk,
-					 masks);
-	if (ret >= 0)
-		nr_others = ret;
-
- fail_build_affinity:
-	cpus_read_unlock();
-
-	if (ret >= 0)
-		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 < 0 ? ret : 0;
-}
+#include <linux/group_cpus.h>
 
 static void default_calc_sets(struct irq_affinity *affd, unsigned int affvecs)
 {
@@ -461,14 +70,18 @@ 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 = group_cpus_evenly(this_vecs);
 
-		ret = irq_build_affinity_masks(curvec, this_vecs,
-					       curvec, masks);
-		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;
 	}