From b3cffc3877a6c7edf17fd9c476f3e8d930bccec1 Mon Sep 17 00:00:00 2001 From: weiping zhang Date: Sat, 30 Sep 2017 09:49:21 +0800 Subject: [PATCH] null_blk: add "no_sched" module parameter add an option that disable io scheduler for null block device. Signed-off-by: weiping zhang Signed-off-by: Jens Axboe --- drivers/block/null_blk.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c index 8042c26ea9e6..bf2c8ca3242a 100644 --- a/drivers/block/null_blk.c +++ b/drivers/block/null_blk.c @@ -154,6 +154,10 @@ enum { NULL_Q_MQ = 2, }; +static int g_no_sched; +module_param_named(no_sched, g_no_sched, int, S_IRUGO); +MODULE_PARM_DESC(no_sched, "No io scheduler"); + static int g_submit_queues = 1; module_param_named(submit_queues, g_submit_queues, int, S_IRUGO); MODULE_PARM_DESC(submit_queues, "Number of submission queues"); @@ -1754,6 +1758,8 @@ static int null_init_tag_set(struct nullb *nullb, struct blk_mq_tag_set *set) set->numa_node = nullb ? nullb->dev->home_node : g_home_node; set->cmd_size = sizeof(struct nullb_cmd); set->flags = BLK_MQ_F_SHOULD_MERGE; + if (g_no_sched) + set->flags |= BLK_MQ_F_NO_SCHED; set->driver_data = NULL; if ((nullb && nullb->dev->blocking) || g_blocking) -- 2.30.2