From: Uwe Kleine-König Date: Thu, 13 Aug 2009 18:38:17 +0000 (+0200) Subject: Use kernel/Kconfig.preempt for ARM X-Git-Tag: v2.6.32-rc1~691^2~1^2~4^2~1 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d45a398fca6b03f16d01c9253c3a8c96d804f532;p=karo-tx-linux.git 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 Cc: Russell King --- diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index aef63c8e3d2d..eac1a927ca6e 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -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