diff options
| -rw-r--r-- | block/blk-mq.c | 34 |
1 files changed, 31 insertions, 3 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index e4aa36817367..c3621453ad87 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2336,7 +2336,7 @@ static void blk_mq_free_map_and_requests(struct blk_mq_tag_set *set, static void blk_mq_map_swqueue(struct request_queue *q) { - unsigned int i; + unsigned int i, hctx_idx; struct blk_mq_hw_ctx *hctx; struct blk_mq_ctx *ctx; struct blk_mq_tag_set *set = q->tag_set; @@ -2353,8 +2353,23 @@ static void blk_mq_map_swqueue(struct request_queue *q) /* * Map software to hardware queues. + * + * If the cpu isn't present, the cpu is mapped to first hctx. */ for_each_possible_cpu(i) { + hctx_idx = q->mq_map[i]; + /* unmapped hw queue can be remapped after CPU topo changed */ + if (!set->tags[hctx_idx] && + !__blk_mq_alloc_rq_map(set, hctx_idx)) { + /* + * If tags initialization fail for some hctx, + * that hctx won't be brought online. In this + * case, remap the current ctx to hctx[0] which + * is guaranteed to always have tags allocated + */ + q->mq_map[i] = 0; + } + ctx = per_cpu_ptr(q->queue_ctx, i); hctx = blk_mq_map_queue(q, i); @@ -2366,8 +2381,21 @@ static void blk_mq_map_swqueue(struct request_queue *q) mutex_unlock(&q->sysfs_lock); queue_for_each_hw_ctx(q, hctx, i) { - /* every hctx should get mapped by at least one CPU */ - WARN_ON(!hctx->nr_ctx); + /* + * If no software queues are mapped to this hardware queue, + * disable it and free the request entries. + */ + if (!hctx->nr_ctx) { + /* Never unmap queue 0. We need it as a + * fallback in case of a new remap fails + * allocation + */ + if (i && set->tags[i]) + blk_mq_free_map_and_requests(set, i); + + hctx->tags = NULL; + continue; + } hctx->tags = set->tags[i]; WARN_ON(!hctx->tags); |