diff options
Diffstat (limited to 'kernel/sched')
| -rw-r--r-- | kernel/sched/fair.c | 30 |
1 files changed, 23 insertions, 7 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 51a7600..f84ac3f 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -1011,6 +1011,23 @@ migrate: return migrate_task_to(p, env.best_cpu); } +/* Attempt to migrate a task to a CPU on the preferred node. */ +static void numa_migrate_preferred(struct task_struct *p) +{ + /* Success if task is already running on preferred CPU */ + p->numa_migrate_retry = 0; + if (cpu_to_node(task_cpu(p)) == p->numa_preferred_nid) + return; + + /* This task has no NUMA fault statistics yet */ + if (unlikely(p->numa_preferred_nid == -1)) + return; + + /* Otherwise, try migrate to a CPU on the preferred node */ + if (task_numa_migrate(p) != 0) + p->numa_migrate_retry = jiffies + HZ*5; +} + static void task_numa_placement(struct task_struct *p) { int seq, nid, max_nid = -1; @@ -1045,17 +1062,12 @@ static void task_numa_placement(struct task_struct *p) } } - /* - * Record the preferred node as the node with the most faults, - * requeue the task to be running on the idlest CPU on the - * preferred node and reset the scanning rate to recheck - * the working set placement. - */ + /* Preferred node as the node with the most faults */ if (max_faults && max_nid != p->numa_preferred_nid) { /* Update the preferred nid and migrate task if possible */ p->numa_preferred_nid = max_nid; p->numa_migrate_seq = 1; - task_numa_migrate(p); + numa_migrate_preferred(p); } } @@ -1111,6 +1123,10 @@ void task_numa_fault(int last_nidpid, int node, int pages, bool migrated) task_numa_placement(p); + /* Retry task to preferred node migration if it previously failed */ + if (p->numa_migrate_retry && time_after(jiffies, p->numa_migrate_retry)) + numa_migrate_preferred(p); + p->numa_faults_buffer[task_faults_idx(node, priv)] += pages; } |