diff options
Diffstat (limited to 'block/blk-mq.c')
| -rw-r--r-- | block/blk-mq.c | 106 |
1 files changed, 33 insertions, 73 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index 6d6f8feb48c0..8398e18d4139 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1783,10 +1783,6 @@ static void blk_mq_init_cpu_queues(struct request_queue *q, INIT_LIST_HEAD(&__ctx->rq_list); __ctx->queue = q; - /* If the cpu isn't online, the cpu is mapped to first hctx */ - if (!cpu_online(i)) - continue; - hctx = q->mq_ops->map_queue(q, i); /* @@ -1820,12 +1816,9 @@ static void blk_mq_map_swqueue(struct request_queue *q, * Map software to hardware queues */ queue_for_each_ctx(q, ctx, i) { - /* If the cpu isn't online, the cpu is mapped to first hctx */ - if (!cpumask_test_cpu(i, online_mask)) - continue; - hctx = q->mq_ops->map_queue(q, i); - cpumask_set_cpu(i, hctx->cpumask); + if (cpumask_test_cpu(i, online_mask)) + cpumask_set_cpu(i, hctx->cpumask); ctx->index_hw = hctx->nr_ctx; hctx->ctxs[hctx->nr_ctx++] = ctx; } @@ -1863,17 +1856,22 @@ static void blk_mq_map_swqueue(struct request_queue *q, /* * Initialize batch roundrobin counts + * Set next_cpu for only those hctxs that have an online CPU + * in their cpumask field. For hctxs that belong to few online + * and few offline CPUs, this will always provide one CPU from + * online ones. For hctxs belonging to all offline CPUs, their + * cpumask will be updated in reinit_notify. */ - hctx->next_cpu = cpumask_first(hctx->cpumask); - hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; + if (cpumask_first(hctx->cpumask) < nr_cpu_ids) { + hctx->next_cpu = cpumask_first(hctx->cpumask); + hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; + } } queue_for_each_ctx(q, ctx, i) { - if (!cpumask_test_cpu(i, online_mask)) - continue; - hctx = q->mq_ops->map_queue(q, i); - cpumask_set_cpu(i, hctx->tags->cpumask); + if (cpumask_test_cpu(i, online_mask)) + cpumask_set_cpu(i, hctx->tags->cpumask); } } @@ -2101,38 +2099,13 @@ void blk_mq_free_queue(struct request_queue *q) blk_mq_free_hw_queues(q, set); } -/* Basically redo blk_mq_init_queue with queue frozen */ -static void blk_mq_queue_reinit(struct request_queue *q, - const struct cpumask *online_mask) -{ - WARN_ON_ONCE(!atomic_read(&q->mq_freeze_depth)); - - blk_mq_sysfs_unregister(q); - - blk_mq_update_queue_map(q->mq_map, q->nr_hw_queues, online_mask); - - /* - * redo blk_mq_init_cpu_queues and blk_mq_init_hw_queues. FIXME: maybe - * we should change hctx numa_node according to new topology (this - * involves free and re-allocate memory, worthy doing?) - */ - - blk_mq_map_swqueue(q, online_mask); - - blk_mq_sysfs_register(q); -} - static int blk_mq_queue_reinit_notify(struct notifier_block *nb, unsigned long action, void *hcpu) { struct request_queue *q; + struct blk_mq_hw_ctx *hctx; + int i; int cpu = (unsigned long)hcpu; - /* - * New online cpumask which is going to be set in this hotplug event. - * Declare this cpumasks as global as cpu-hotplug operation is invoked - * one-by-one and dynamically allocating this could result in a failure. - */ - static struct cpumask online_new; /* * Before hotadded cpu starts handling requests, new mappings must @@ -2154,44 +2127,31 @@ static int blk_mq_queue_reinit_notify(struct notifier_block *nb, switch (action & ~CPU_TASKS_FROZEN) { case CPU_DEAD: case CPU_UP_CANCELED: - cpumask_copy(&online_new, cpu_online_mask); + mutex_lock(&all_q_mutex); + list_for_each_entry(q, &all_q_list, all_q_node) { + queue_for_each_hw_ctx(q, hctx, i) { + cpumask_clear_cpu(cpu, hctx->cpumask); + cpumask_clear_cpu(cpu, hctx->tags->cpumask); + } + } + mutex_unlock(&all_q_mutex); break; case CPU_UP_PREPARE: - cpumask_copy(&online_new, cpu_online_mask); - cpumask_set_cpu(cpu, &online_new); + /* Update hctx->cpumask for newly onlined CPUs */ + mutex_lock(&all_q_mutex); + list_for_each_entry(q, &all_q_list, all_q_node) { + queue_for_each_hw_ctx(q, hctx, i) { + cpumask_set_cpu(cpu, hctx->cpumask); + hctx->next_cpu_batch = BLK_MQ_CPU_WORK_BATCH; + cpumask_set_cpu(cpu, hctx->tags->cpumask); + } + } + mutex_unlock(&all_q_mutex); break; default: return NOTIFY_OK; } - mutex_lock(&all_q_mutex); - - /* - * We need to freeze and reinit all existing queues. Freezing - * involves synchronous wait for an RCU grace period and doing it - * one by one may take a long time. Start freezing all queues in - * one swoop and then wait for the completions so that freezing can - * take place in parallel. - */ - list_for_each_entry(q, &all_q_list, all_q_node) - blk_mq_freeze_queue_start(q); - list_for_each_entry(q, &all_q_list, all_q_node) { - blk_mq_freeze_queue_wait(q); - - /* - * timeout handler can't touch hw queue during the - * reinitialization - */ - del_timer_sync(&q->timeout); - } - - list_for_each_entry(q, &all_q_list, all_q_node) - blk_mq_queue_reinit(q, &online_new); - - list_for_each_entry(q, &all_q_list, all_q_node) - blk_mq_unfreeze_queue(q); - - mutex_unlock(&all_q_mutex); return NOTIFY_OK; } |