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authorIngo Molnar <mingo@kernel.org>2015-06-02 02:05:42 -0400
committerIngo Molnar <mingo@kernel.org>2015-06-02 02:05:42 -0400
commitf407a8258610169cd8e975dba7f0b2824562014c (patch)
tree6c87b2d168a4665411a9e16b9f481599f2db25bc /lib/cpumask.c
parent960d447b94b22ceba286917056871d1dac8da697 (diff)
parentc46a024ea5eb0165114dbbc8c82c29b7bcf66e71 (diff)
Merge branch 'linus' into sched/core, to resolve conflict
Conflicts: arch/sparc/include/asm/topology_64.h Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'lib/cpumask.c')
-rw-r--r--lib/cpumask.c74
1 files changed, 26 insertions, 48 deletions
diff --git a/lib/cpumask.c b/lib/cpumask.c
index 830dd5dec40f..5f627084f2e9 100644
--- a/lib/cpumask.c
+++ b/lib/cpumask.c
@@ -139,64 +139,42 @@ void __init free_bootmem_cpumask_var(cpumask_var_t mask)
139#endif 139#endif
140 140
141/** 141/**
142 * cpumask_set_cpu_local_first - set i'th cpu with local numa cpu's first 142 * cpumask_local_spread - select the i'th cpu with local numa cpu's first
143 *
144 * @i: index number 143 * @i: index number
145 * @numa_node: local numa_node 144 * @node: local numa_node
146 * @dstp: cpumask with the relevant cpu bit set according to the policy
147 * 145 *
148 * This function sets the cpumask according to a numa aware policy. 146 * This function selects an online CPU according to a numa aware policy;
149 * cpumask could be used as an affinity hint for the IRQ related to a 147 * local cpus are returned first, followed by non-local ones, then it
150 * queue. When the policy is to spread queues across cores - local cores 148 * wraps around.
151 * first.
152 * 149 *
153 * Returns 0 on success, -ENOMEM for no memory, and -EAGAIN when failed to set 150 * It's not very efficient, but useful for setup.
154 * the cpu bit and need to re-call the function.
155 */ 151 */
156int cpumask_set_cpu_local_first(int i, int numa_node, cpumask_t *dstp) 152unsigned int cpumask_local_spread(unsigned int i, int node)
157{ 153{
158 cpumask_var_t mask;
159 int cpu; 154 int cpu;
160 int ret = 0;
161
162 if (!zalloc_cpumask_var(&mask, GFP_KERNEL))
163 return -ENOMEM;
164 155
156 /* Wrap: we always want a cpu. */
165 i %= num_online_cpus(); 157 i %= num_online_cpus();
166 158
167 if (numa_node == -1 || !cpumask_of_node(numa_node)) { 159 if (node == -1) {
168 /* Use all online cpu's for non numa aware system */ 160 for_each_cpu(cpu, cpu_online_mask)
169 cpumask_copy(mask, cpu_online_mask); 161 if (i-- == 0)
162 return cpu;
170 } else { 163 } else {
171 int n; 164 /* NUMA first. */
172 165 for_each_cpu_and(cpu, cpumask_of_node(node), cpu_online_mask)
173 cpumask_and(mask, 166 if (i-- == 0)
174 cpumask_of_node(numa_node), cpu_online_mask); 167 return cpu;
175 168
176 n = cpumask_weight(mask); 169 for_each_cpu(cpu, cpu_online_mask) {
177 if (i >= n) { 170 /* Skip NUMA nodes, done above. */
178 i -= n; 171 if (cpumask_test_cpu(cpu, cpumask_of_node(node)))
179 172 continue;
180 /* If index > number of local cpu's, mask out local 173
181 * cpu's 174 if (i-- == 0)
182 */ 175 return cpu;
183 cpumask_andnot(mask, cpu_online_mask, mask);
184 } 176 }
185 } 177 }
186 178 BUG();
187 for_each_cpu(cpu, mask) {
188 if (--i < 0)
189 goto out;
190 }
191
192 ret = -EAGAIN;
193
194out:
195 free_cpumask_var(mask);
196
197 if (!ret)
198 cpumask_set_cpu(cpu, dstp);
199
200 return ret;
201} 179}
202EXPORT_SYMBOL(cpumask_set_cpu_local_first); 180EXPORT_SYMBOL(cpumask_local_spread);