diff options
| -rw-r--r-- | block/blk-mq.c | 30 |
1 files changed, 28 insertions, 2 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index c8f62e6..3bd41f1 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1319,21 +1319,47 @@ static void __blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx) */ static int blk_mq_hctx_next_cpu(struct blk_mq_hw_ctx *hctx) { + bool tried = false; + if (hctx->queue->nr_hw_queues == 1) return WORK_CPU_UNBOUND; if (--hctx->next_cpu_batch <= 0) { int next_cpu; - +select_cpu: next_cpu = cpumask_next_and(hctx->next_cpu, hctx->cpumask, cpu_online_mask); if (next_cpu >= nr_cpu_ids) next_cpu = cpumask_first_and(hctx->cpumask,cpu_online_mask); - hctx->next_cpu = next_cpu; + /* + * No online CPU is found, so have to make sure hctx->next_cpu + * is set correctly for not breaking workqueue. + */ + if (next_cpu >= nr_cpu_ids) + hctx->next_cpu = cpumask_first(hctx->cpumask); + else + hctx->next_cpu = next_cpu; hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; } + /* + * Do unbound schedule if we can't find a online CPU for this hctx, + * and it should only happen in the path of handling CPU DEAD. + */ + if (!cpu_online(hctx->next_cpu)) { + if (!tried) { + tried = true; + goto select_cpu; + } + + /* + * Make sure to re-select CPU next time once after CPUs + * in hctx->cpumask become online again. + */ + hctx->next_cpu_batch = 1; + return WORK_CPU_UNBOUND; + } return hctx->next_cpu; } |
