From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Sat, 30 Sep 2017 01:09:57 +0800 From: weiping zhang To: CC: Subject: [PATCH] null_blk: add "no_sched" module parameter Message-ID: <20170929170951.GA18535@localhost.didichuxing.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-Path: zhangweiping@didichuxing.com List-ID: add an option that disable io scheduler for null block device. Signed-off-by: weiping zhang --- drivers/block/null_blk.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c index bd92286..3c63863 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"); @@ -1753,7 +1757,7 @@ static int null_init_tag_set(struct nullb *nullb, struct blk_mq_tag_set *set) g_hw_queue_depth; 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; + set->flags = g_no_sched ? BLK_MQ_F_NO_SCHED : BLK_MQ_F_SHOULD_MERGE; set->driver_data = NULL; if ((nullb && nullb->dev->blocking) || g_blocking) -- 2.9.4