blk-mq-sched: allow setting of default IO scheduler
Add Kconfig entries to manage what devices get assigned an MQ
scheduler, and add a blk-mq flag for drivers to opt out of scheduling.
The latter is useful for admin type queues that still allocate a blk-mq
queue and tag set, but aren't use for normal IO.
Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
diff --git a/block/Kconfig.iosched b/block/Kconfig.iosched
index 490ef28..0715ce9 100644
--- a/block/Kconfig.iosched
+++ b/block/Kconfig.iosched
@@ -32,12 +32,6 @@
This is the default I/O scheduler.
-config MQ_IOSCHED_DEADLINE
- tristate "MQ deadline I/O scheduler"
- default y
- ---help---
- MQ version of the deadline IO scheduler.
-
config CFQ_GROUP_IOSCHED
bool "CFQ Group Scheduling support"
depends on IOSCHED_CFQ && BLK_CGROUP
@@ -69,6 +63,56 @@
default "cfq" if DEFAULT_CFQ
default "noop" if DEFAULT_NOOP
+config MQ_IOSCHED_DEADLINE
+ tristate "MQ deadline I/O scheduler"
+ default y
+ ---help---
+ MQ version of the deadline IO scheduler.
+
+config MQ_IOSCHED_NONE
+ bool
+ default y
+
+choice
+ prompt "Default single-queue blk-mq I/O scheduler"
+ default DEFAULT_SQ_NONE
+ help
+ Select the I/O scheduler which will be used by default for blk-mq
+ managed block devices with a single queue.
+
+ config DEFAULT_SQ_DEADLINE
+ bool "MQ Deadline" if MQ_IOSCHED_DEADLINE=y
+
+ config DEFAULT_SQ_NONE
+ bool "None"
+
+endchoice
+
+config DEFAULT_SQ_IOSCHED
+ string
+ default "mq-deadline" if DEFAULT_SQ_DEADLINE
+ default "none" if DEFAULT_SQ_NONE
+
+choice
+ prompt "Default multi-queue blk-mq I/O scheduler"
+ default DEFAULT_MQ_NONE
+ help
+ Select the I/O scheduler which will be used by default for blk-mq
+ managed block devices with multiple queues.
+
+ config DEFAULT_MQ_DEADLINE
+ bool "MQ Deadline" if MQ_IOSCHED_DEADLINE=y
+
+ config DEFAULT_MQ_NONE
+ bool "None"
+
+endchoice
+
+config DEFAULT_MQ_IOSCHED
+ string
+ default "mq-deadline" if DEFAULT_MQ_DEADLINE
+ default "none" if DEFAULT_MQ_NONE
+
endmenu
endif