From 6637fadf25657e619a50fde5ff3ae09a98d20eb5 Mon Sep 17 00:00:00 2001 From: Shaohua Li Date: Sun, 30 Nov 2014 16:00:58 -0800 Subject: [PATCH] blk-mq: move the kdump check to blk_mq_alloc_tag_set We call blk_mq_alloc_tag_set() first then blk_mq_init_queue(). The requests are allocated in the former function. So the kdump check should be moved to there to really save memory. Signed-off-by: Shaohua Li Signed-off-by: Jens Axboe --- block/blk-mq.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 27a347fe8f5b..4854e709aa34 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1804,16 +1804,6 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set) if (!ctx) return ERR_PTR(-ENOMEM); - /* - * If a crashdump is active, then we are potentially in a very - * memory constrained environment. Limit us to 1 queue and - * 64 tags to prevent using too much memory. - */ - if (is_kdump_kernel()) { - set->nr_hw_queues = 1; - set->queue_depth = min(64U, set->queue_depth); - } - hctxs = kmalloc_node(set->nr_hw_queues * sizeof(*hctxs), GFP_KERNEL, set->numa_node); @@ -2070,6 +2060,16 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) set->queue_depth = BLK_MQ_MAX_DEPTH; } + /* + * If a crashdump is active, then we are potentially in a very + * memory constrained environment. Limit us to 1 queue and + * 64 tags to prevent using too much memory. + */ + if (is_kdump_kernel()) { + set->nr_hw_queues = 1; + set->queue_depth = min(64U, set->queue_depth); + } + set->tags = kmalloc_node(set->nr_hw_queues * sizeof(struct blk_mq_tags *), GFP_KERNEL, set->numa_node); -- 2.20.1