diff options
| -rw-r--r-- | kernel/sched_rt.c | 25 |
1 files changed, 18 insertions, 7 deletions
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 72c8132..52d88f1 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -303,7 +303,7 @@ static int find_lowest_cpus(struct task_struct *task, cpumask_t *lowest_mask) int cpu; cpumask_t *valid_mask = &__get_cpu_var(valid_cpu_mask); int lowest_prio = -1; - int ret = 0; + int count = 0; cpus_clear(*lowest_mask); cpus_and(*valid_mask, cpu_online_map, task->cpus_allowed); @@ -316,7 +316,7 @@ static int find_lowest_cpus(struct task_struct *task, cpumask_t *lowest_mask) /* We look for lowest RT prio or non-rt CPU */ if (rq->rt.highest_prio >= MAX_RT_PRIO) { - if (ret) + if (count) cpus_clear(*lowest_mask); cpu_set(rq->cpu, *lowest_mask); return 1; @@ -328,14 +328,17 @@ static int find_lowest_cpus(struct task_struct *task, cpumask_t *lowest_mask) if (rq->rt.highest_prio > lowest_prio) { /* new low - clear old data */ lowest_prio = rq->rt.highest_prio; - cpus_clear(*lowest_mask); + if (count) { + cpus_clear(*lowest_mask); + count = 0; + } } cpu_set(rq->cpu, *lowest_mask); - ret = 1; + count++; } } - return ret; + return count; } static inline int pick_optimal_cpu(int this_cpu, cpumask_t *mask) @@ -359,9 +362,17 @@ static int find_lowest_rq(struct task_struct *task) cpumask_t *lowest_mask = &__get_cpu_var(local_cpu_mask); int this_cpu = smp_processor_id(); int cpu = task_cpu(task); + int count = find_lowest_cpus(task, lowest_mask); - if (!find_lowest_cpus(task, lowest_mask)) - return -1; + if (!count) + return -1; /* No targets found */ + + /* + * There is no sense in performing an optimal search if only one + * target is found. + */ + if (count == 1) + return first_cpu(*lowest_mask); /* * At this point we have built a mask of cpus representing the |