+#ifdef CONFIG_NUMA
+
+static int sched_domains_numa_levels;
+static int sched_domains_numa_scale;
+static int *sched_domains_numa_distance;
+static struct cpumask ***sched_domains_numa_masks;
+static int sched_domains_curr_level;
+
+static inline unsigned long numa_scale(unsigned long x, int level)
+{
+ return x * sched_domains_numa_distance[level] / sched_domains_numa_scale;
+}
+
+static inline int sd_local_flags(int level)
+{
+ if (sched_domains_numa_distance[level] > REMOTE_DISTANCE)
+ return 0;
+
+ return SD_BALANCE_EXEC | SD_BALANCE_FORK | SD_WAKE_AFFINE;
+}
+
+static struct sched_domain *
+sd_numa_init(struct sched_domain_topology_level *tl, int cpu)
+{
+ struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu);
+ int level = tl->numa_level;
+ int sd_weight = cpumask_weight(
+ sched_domains_numa_masks[level][cpu_to_node(cpu)]);
+
+ *sd = (struct sched_domain){
+ .min_interval = sd_weight,
+ .max_interval = 2*sd_weight,
+ .busy_factor = 32,
+ .imbalance_pct = 100 + numa_scale(25, level),
+ .cache_nice_tries = 2,
+ .busy_idx = 3,
+ .idle_idx = 2,
+ .newidle_idx = 0,
+ .wake_idx = 0,
+ .forkexec_idx = 0,
+
+ .flags = 1*SD_LOAD_BALANCE
+ | 1*SD_BALANCE_NEWIDLE
+ | 0*SD_BALANCE_EXEC
+ | 0*SD_BALANCE_FORK
+ | 0*SD_BALANCE_WAKE
+ | 0*SD_WAKE_AFFINE
+ | 0*SD_PREFER_LOCAL
+ | 0*SD_SHARE_CPUPOWER
+ | 0*SD_POWERSAVINGS_BALANCE
+ | 0*SD_SHARE_PKG_RESOURCES
+ | 1*SD_SERIALIZE
+ | 0*SD_PREFER_SIBLING
+ | sd_local_flags(level)
+ ,
+ .last_balance = jiffies,
+ .balance_interval = sd_weight,
+ };
+ SD_INIT_NAME(sd, NUMA);
+ sd->private = &tl->data;
+
+ /*
+ * Ugly hack to pass state to sd_numa_mask()...
+ */
+ sched_domains_curr_level = tl->numa_level;
+
+ return sd;
+}
+
+static const struct cpumask *sd_numa_mask(int cpu)
+{
+ return sched_domains_numa_masks[sched_domains_curr_level][cpu_to_node(cpu)];
+}
+
+static void sched_init_numa(void)
+{
+ int next_distance, curr_distance = node_distance(0, 0);
+ struct sched_domain_topology_level *tl;
+ int level = 0;
+ int i, j, k;
+
+ sched_domains_numa_scale = curr_distance;
+ sched_domains_numa_distance = kzalloc(sizeof(int) * nr_node_ids, GFP_KERNEL);
+ if (!sched_domains_numa_distance)
+ return;
+
+ /*
+ * O(nr_nodes^2) deduplicating selection sort -- in order to find the
+ * unique distances in the node_distance() table.
+ *
+ * Assumes node_distance(0,j) includes all distances in
+ * node_distance(i,j) in order to avoid cubic time.
+ *
+ * XXX: could be optimized to O(n log n) by using sort()
+ */
+ next_distance = curr_distance;
+ for (i = 0; i < nr_node_ids; i++) {
+ for (j = 0; j < nr_node_ids; j++) {
+ int distance = node_distance(0, j);
+ if (distance > curr_distance &&
+ (distance < next_distance ||
+ next_distance == curr_distance))
+ next_distance = distance;
+ }
+ if (next_distance != curr_distance) {
+ sched_domains_numa_distance[level++] = next_distance;
+ sched_domains_numa_levels = level;
+ curr_distance = next_distance;
+ } else break;
+ }
+ /*
+ * 'level' contains the number of unique distances, excluding the
+ * identity distance node_distance(i,i).
+ *
+ * The sched_domains_nume_distance[] array includes the actual distance
+ * numbers.
+ */
+
+ sched_domains_numa_masks = kzalloc(sizeof(void *) * level, GFP_KERNEL);
+ if (!sched_domains_numa_masks)
+ return;
+
+ /*
+ * Now for each level, construct a mask per node which contains all
+ * cpus of nodes that are that many hops away from us.
+ */
+ for (i = 0; i < level; i++) {
+ sched_domains_numa_masks[i] =
+ kzalloc(nr_node_ids * sizeof(void *), GFP_KERNEL);
+ if (!sched_domains_numa_masks[i])
+ return;
+
+ for (j = 0; j < nr_node_ids; j++) {
+ struct cpumask *mask = kzalloc_node(cpumask_size(), GFP_KERNEL, j);
+ if (!mask)
+ return;
+
+ sched_domains_numa_masks[i][j] = mask;
+
+ for (k = 0; k < nr_node_ids; k++) {
+ if (node_distance(cpu_to_node(j), k) >
+ sched_domains_numa_distance[i])
+ continue;
+
+ cpumask_or(mask, mask, cpumask_of_node(k));
+ }
+ }
+ }
+
+ tl = kzalloc((ARRAY_SIZE(default_topology) + level) *
+ sizeof(struct sched_domain_topology_level), GFP_KERNEL);
+ if (!tl)
+ return;
+
+ /*
+ * Copy the default topology bits..
+ */
+ for (i = 0; default_topology[i].init; i++)
+ tl[i] = default_topology[i];
+
+ /*
+ * .. and append 'j' levels of NUMA goodness.
+ */
+ for (j = 0; j < level; i++, j++) {
+ tl[i] = (struct sched_domain_topology_level){
+ .init = sd_numa_init,
+ .mask = sd_numa_mask,
+ .flags = SDTL_OVERLAP,
+ .numa_level = j,
+ };
+ }
+
+ sched_domain_topology = tl;
+}
+#else
+static inline void sched_init_numa(void)
+{
+}
+#endif /* CONFIG_NUMA */
+
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