[PATCH 8/8] loop: allow user to set the queue depth

Chaitanya Kulkarni
2022-02-14T10:37:11Z

Instead of hardcoding queue depth allow user to set the hw queue depth
using module parameter. Set default value to 128 to retain the existing
behavior.

Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
---
drivers/block/loop.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 18b30a56bfc4..fd2184d63c11 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1785,6 +1785,9 @@ module_param(max_loop, int, 0444);
MODULE_PARM_DESC(max_loop, "Maximum number of loop devices");
module_param(max_part, int, 0444);
MODULE_PARM_DESC(max_part, "Maximum number of partitions per loop device");
+static int hw_queue_depth = 128;
+module_param_named(hw_queue_depth, hw_queue_depth, int, 0444);
+MODULE_PARM_DESC(hw_queue_depth, "Queue depth for each hardware queue. Default: 128");
MODULE_LICENSE("GPL");
MODULE_ALIAS_BLOCKDEV_MAJOR(LOOP_MAJOR);

@@ -1979,7 +1982,7 @@ static int loop_add(int i)

lo->tag_set.ops = &loop_mq_ops;
lo->tag_set.nr_hw_queues = 1;
- lo->tag_set.queue_depth = 128;
+ lo->tag_set.queue_depth = hw_queue_depth;
lo->tag_set.numa_node = NUMA_NO_NODE;
lo->tag_set.cmd_size = sizeof(struct loop_cmd);
lo->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_STACKING |
--
2.29.0