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if CONFIG_BLOCK

menu "IO Schedulers"

config CONFIG_IOSCHED_NOOP
	bool
	default y
	---help---
	  The no-op I/O scheduler is a minimal scheduler that does basic merging
	  and sorting. Its main uses include non-disk based block devices like
	  memory devices, and specialised software or hardware environments
	  that do their own scheduling and require only minimal assistance from
	  the kernel.

config CONFIG_IOSCHED_DEADLINE
	tristate "Deadline I/O scheduler"
	default y
	---help---
	  The deadline I/O scheduler is simple and compact. It will provide
	  CSCAN service with FIFO expiration of requests, switching to
	  a new point in the service tree and doing a batch of IO from there
	  in case of expiry.

config CONFIG_IOSCHED_CFQ
	tristate "CFQ I/O scheduler"
	default y
	---help---
	  The CFQ I/O scheduler tries to distribute bandwidth equally
	  among all processes in the system. It should provide a fair
	  and low latency working environment, suitable for both desktop
	  and server systems.

	  This is the default I/O scheduler.

config CONFIG_CFQ_GROUP_IOSCHED
	bool "CFQ Group Scheduling support"
	depends on CONFIG_IOSCHED_CFQ && CONFIG_BLK_CGROUP
	default n
	---help---
	  Enable group IO scheduling in CFQ.

choice
	prompt "Default I/O scheduler"
	default CONFIG_DEFAULT_CFQ
	help
	  Select the I/O scheduler which will be used by default for all
	  block devices.

	config CONFIG_DEFAULT_DEADLINE
		bool "Deadline" if CONFIG_IOSCHED_DEADLINE=y

	config CONFIG_DEFAULT_CFQ
		bool "CFQ" if CONFIG_IOSCHED_CFQ=y

	config CONFIG_DEFAULT_NOOP
		bool "No-op"

endchoice

config CONFIG_DEFAULT_IOSCHED
	string
	default "deadline" if CONFIG_DEFAULT_DEADLINE
	default "cfq" if CONFIG_DEFAULT_CFQ
	default "noop" if CONFIG_DEFAULT_NOOP

endmenu

endif