aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--kernel/sched_rt.c61
1 files changed, 24 insertions, 37 deletions
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index a4d790cddb19..5c5fef378415 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1153,29 +1153,12 @@ static struct task_struct *pick_next_highest_task_rt(struct rq *rq, int cpu)
1153 1153
1154static DEFINE_PER_CPU(cpumask_var_t, local_cpu_mask); 1154static DEFINE_PER_CPU(cpumask_var_t, local_cpu_mask);
1155 1155
1156static inline int pick_optimal_cpu(int this_cpu,
1157 const struct cpumask *mask)
1158{
1159 int first;
1160
1161 /* "this_cpu" is cheaper to preempt than a remote processor */
1162 if ((this_cpu != -1) && cpumask_test_cpu(this_cpu, mask))
1163 return this_cpu;
1164
1165 first = cpumask_first(mask);
1166 if (first < nr_cpu_ids)
1167 return first;
1168
1169 return -1;
1170}
1171
1172static int find_lowest_rq(struct task_struct *task) 1156static int find_lowest_rq(struct task_struct *task)
1173{ 1157{
1174 struct sched_domain *sd; 1158 struct sched_domain *sd;
1175 struct cpumask *lowest_mask = __get_cpu_var(local_cpu_mask); 1159 struct cpumask *lowest_mask = __get_cpu_var(local_cpu_mask);
1176 int this_cpu = smp_processor_id(); 1160 int this_cpu = smp_processor_id();
1177 int cpu = task_cpu(task); 1161 int cpu = task_cpu(task);
1178 cpumask_var_t domain_mask;
1179 1162
1180 if (task->rt.nr_cpus_allowed == 1) 1163 if (task->rt.nr_cpus_allowed == 1)
1181 return -1; /* No other targets possible */ 1164 return -1; /* No other targets possible */
@@ -1198,28 +1181,26 @@ static int find_lowest_rq(struct task_struct *task)
1198 * Otherwise, we consult the sched_domains span maps to figure 1181 * Otherwise, we consult the sched_domains span maps to figure
1199 * out which cpu is logically closest to our hot cache data. 1182 * out which cpu is logically closest to our hot cache data.
1200 */ 1183 */
1201 if (this_cpu == cpu) 1184 if (!cpumask_test_cpu(this_cpu, lowest_mask))
1202 this_cpu = -1; /* Skip this_cpu opt if the same */ 1185 this_cpu = -1; /* Skip this_cpu opt if not among lowest */
1203
1204 if (alloc_cpumask_var(&domain_mask, GFP_ATOMIC)) {
1205 for_each_domain(cpu, sd) {
1206 if (sd->flags & SD_WAKE_AFFINE) {
1207 int best_cpu;
1208 1186
1209 cpumask_and(domain_mask, 1187 for_each_domain(cpu, sd) {
1210 sched_domain_span(sd), 1188 if (sd->flags & SD_WAKE_AFFINE) {
1211 lowest_mask); 1189 int best_cpu;
1212 1190
1213 best_cpu = pick_optimal_cpu(this_cpu, 1191 /*
1214 domain_mask); 1192 * "this_cpu" is cheaper to preempt than a
1215 1193 * remote processor.
1216 if (best_cpu != -1) { 1194 */
1217 free_cpumask_var(domain_mask); 1195 if (this_cpu != -1 &&
1218 return best_cpu; 1196 cpumask_test_cpu(this_cpu, sched_domain_span(sd)))
1219 } 1197 return this_cpu;
1220 } 1198
1199 best_cpu = cpumask_first_and(lowest_mask,
1200 sched_domain_span(sd));
1201 if (best_cpu < nr_cpu_ids)
1202 return best_cpu;
1221 } 1203 }
1222 free_cpumask_var(domain_mask);
1223 } 1204 }
1224 1205
1225 /* 1206 /*
@@ -1227,7 +1208,13 @@ static int find_lowest_rq(struct task_struct *task)
1227 * just give the caller *something* to work with from the compatible 1208 * just give the caller *something* to work with from the compatible
1228 * locations. 1209 * locations.
1229 */ 1210 */
1230 return pick_optimal_cpu(this_cpu, lowest_mask); 1211 if (this_cpu != -1)
1212 return this_cpu;
1213
1214 cpu = cpumask_any(lowest_mask);
1215 if (cpu < nr_cpu_ids)
1216 return cpu;
1217 return -1;
1231} 1218}
1232 1219
1233/* Will lock the rq it finds */ 1220/* Will lock the rq it finds */