sched: drop for_each_numa_hop_mask()

Now that we have for_each_numa_cpu(), for_each_numa_hop_mask()
and all related code is a dead code. Drop it.

Signed-off-by: Yury Norov <yury.norov@gmail.com>

include/linux/topology.h

@@ -252,7 +252,6 @@ static inline const struct cpumask *cpu_cpu_mask(int cpu)
 #ifdef CONFIG_NUMA
 int sched_numa_find_nth_cpu(const struct cpumask *cpus, int cpu, int node);
 int sched_numa_find_next_cpu(const struct cpumask *cpus, int cpu, int node, unsigned int *hop);
-extern const struct cpumask *sched_numa_hop_mask(unsigned int node, unsigned int hops);
 #else
 static __always_inline int sched_numa_find_nth_cpu(const struct cpumask *cpus, int cpu, int node)
 {
@@ -265,32 +264,8 @@ int sched_numa_find_next_cpu(const struct cpumask *cpus, int cpu, int node, unsi
 	return find_next_and_bit(cpumask_bits(cpus), cpumask_bits(cpu_online_mask),
 						small_cpumask_bits, cpu);
 }
-
-static inline const struct cpumask *
-sched_numa_hop_mask(unsigned int node, unsigned int hops)
-{
-	return ERR_PTR(-EOPNOTSUPP);
-}
 #endif	/* CONFIG_NUMA */
 
-/**
- * for_each_numa_hop_mask - iterate over cpumasks of increasing NUMA distance
- *                          from a given node.
- * @mask: the iteration variable.
- * @node: the NUMA node to start the search from.
- *
- * Requires rcu_lock to be held.
- *
- * Yields cpu_online_mask for @node == NUMA_NO_NODE.
- */
-#define for_each_numa_hop_mask(mask, node)				       \
-	for (unsigned int __hops = 0;					       \
-	     mask = (node != NUMA_NO_NODE || __hops) ?			       \
-		     sched_numa_hop_mask(node, __hops) :		       \
-		     cpu_online_mask,					       \
-	     !IS_ERR_OR_NULL(mask);					       \
-	     __hops++)
-
 /**
  * for_each_numa_cpu - iterate over cpus in increasing order taking into account
  *		       NUMA distances from a given node.

kernel/sched/topology.c

@@ -2174,38 +2174,6 @@ int sched_numa_find_next_cpu(const struct cpumask *cpus, int cpu, int node, unsi
 }
 EXPORT_SYMBOL_GPL(sched_numa_find_next_cpu);
 
-/**
- * sched_numa_hop_mask() - Get the cpumask of CPUs at most @hops hops away from
- *                         @node
- * @node: The node to count hops from.
- * @hops: Include CPUs up to that many hops away. 0 means local node.
- *
- * Return: On success, a pointer to a cpumask of CPUs at most @hops away from
- * @node, an error value otherwise.
- *
- * Requires rcu_lock to be held. Returned cpumask is only valid within that
- * read-side section, copy it if required beyond that.
- *
- * Note that not all hops are equal in distance; see sched_init_numa() for how
- * distances and masks are handled.
- * Also note that this is a reflection of sched_domains_numa_masks, which may change
- * during the lifetime of the system (offline nodes are taken out of the masks).
- */
-const struct cpumask *sched_numa_hop_mask(unsigned int node, unsigned int hops)
-{
-	struct cpumask ***masks;
-
-	if (node >= nr_node_ids || hops >= sched_domains_numa_levels)
-		return ERR_PTR(-EINVAL);
-
-	masks = rcu_dereference(sched_domains_numa_masks);
-	if (!masks)
-		return ERR_PTR(-EBUSY);
-
-	return masks[hops][node];
-}
-EXPORT_SYMBOL_GPL(sched_numa_hop_mask);
-
 #endif /* CONFIG_NUMA */
 
 static int __sdt_alloc(const struct cpumask *cpu_map)