Commit d45a398f authored Aug 13, 2009 by Uwe Kleine-König

Use kernel/Kconfig.preempt for ARM



before this patch ARM had it's own definition of CONFIG_PREEMPT.
Instead of that use the general definition provided in
kernel/Kconfig.preempt.

This patch changes the available options in *config.  Namely PREEMPT
isn't a stand alone bool anymore, but part of a 'choice' the
following Kconfig symbols are added:

	PREEMPT_NONE
	PREEMPT_VOLUNTARY

Selecting PREEMPT_NONE now produces exactly the code as not selecting
PREEMPT before (apart from a comment in
/sys/kernel/debug/tracing/(per_cpu/cpuX/)?trace).  The only difference
PREEMPT_VOLUNTARY does is that might_resched might reschedule.  Both
should't introduce regressions.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Russell King <linux@arm.linux.org.uk>

parent 0d928b0b

arch/arm/Kconfig

+1 −12

Original line number	Diff line number	Diff line
		@@ -962,18 +962,7 @@ config LOCAL_TIMERS
		accounting to be spread across the timer interval, preventing a
		"thundering herd" at every timer tick.

		config PREEMPT
		bool "Preemptible Kernel (EXPERIMENTAL)"
		depends on EXPERIMENTAL
		help
		This option reduces the latency of the kernel when reacting to
		real-time or interactive events by allowing a low priority process to
		be preempted even if it is in kernel mode executing a system call.
		This allows applications to run more reliably even when the system is
		under load.

		Say Y here if you are building a kernel for a desktop, embedded
		or real-time system. Say N if you are unsure.
		source kernel/Kconfig.preempt

		config HZ
		int