--- block/Kconfig.iosched

+++ block/Kconfig.iosched

@@ -40,6 +40,28 @@ config IOSCHED_CFQ

working environment, suitable for desktop systems.

This is the default I/O scheduler.

+config IOSCHED_BFQ

+ tristate "BFQ I/O scheduler"

+ depends on EXPERIMENTAL

+ default n

+ ---help---

+ The BFQ I/O scheduler tries to distribute bandwidth among

+ all processes according to their weights.

+ It aims at distributing the bandwidth as desired, independently of

+ the disk parameters and with any workload. It also tries to

+ guarantee low latency to interactive and soft real-time

+ applications. If compiled built-in (saying Y here), BFQ can

+ be configured to support hierarchical scheduling.

+

+config CGROUP_BFQIO

+ bool "BFQ hierarchical scheduling support"

+ depends on CGROUPS && IOSCHED_BFQ=y

+ default n

+ ---help---

+ Enable hierarchical scheduling in BFQ, using the cgroups

+ filesystem interface. The name of the subsystem will be

+ bfqio.

+

choice

prompt "Default I/O scheduler"

default DEFAULT_CFQ

@@ -56,6 +78,9 @@ choice

config DEFAULT_CFQ

bool "CFQ" if IOSCHED_CFQ=y

+ config DEFAULT_BFQ

+ bool "BFQ" if IOSCHED_BFQ=y

+

config DEFAULT_NOOP

bool "No-op"

@@ -66,6 +91,7 @@ config DEFAULT_IOSCHED

default "anticipatory" if DEFAULT_AS

default "deadline" if DEFAULT_DEADLINE

default "cfq" if DEFAULT_CFQ

+ default "bfq" if DEFAULT_BFQ

default "noop" if DEFAULT_NOOP

endmenu