Commit cc19ca86 authored by Ingo Molnar's avatar Ingo Molnar Committed by Linus Torvalds

[PATCH] consolidate PREEMPT options into kernel/Kconfig.preempt

This patch consolidates the CONFIG_PREEMPT and CONFIG_PREEMPT_BKL
preemption options into kernel/Kconfig.preempt.  This, besides reducing
source-code, also enables more centralized tweaking of preemption related
options.
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 7f1867a5
......@@ -510,28 +510,7 @@ config SCHED_SMT
cost of slightly increased overhead in some places. If unsure say
N here.
config PREEMPT
bool "Preemptible Kernel"
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.
config PREEMPT_BKL
bool "Preempt The Big Kernel Lock"
depends on PREEMPT
default y
help
This option reduces the latency of the kernel by making the
big kernel lock preemptible.
Say Y here if you are building a kernel for a desktop system.
Say N if you are unsure.
source "kernel/Kconfig.preempt"
config X86_UP_APIC
bool "Local APIC support on uniprocessors"
......
......@@ -270,26 +270,7 @@ config SCHED_SMT
when dealing with POWER5 cpus at a cost of slightly increased
overhead in some places. If unsure say N here.
config PREEMPT
bool "Preemptible Kernel"
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.
Say Y here if you are building a kernel for a desktop, embedded
or real-time system. Say N if you are unsure.
config PREEMPT_BKL
bool "Preempt The Big Kernel Lock"
depends on PREEMPT
default y
help
This option reduces the latency of the kernel by making the
big kernel lock preemptible.
Say Y here if you are building a kernel for a desktop system.
Say N if you are unsure.
source "kernel/Kconfig.preempt"
config EEH
bool "PCI Extended Error Handling (EEH)" if EMBEDDED
......
......@@ -207,33 +207,6 @@ config SMP
If you don't know what to do here, say N.
config PREEMPT
bool "Preemptible Kernel"
---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. On contrary it may also break your drivers and add
priority inheritance problems to your system. Don't select it if
you rely on a stable system or have slightly obscure hardware.
It's also not very well tested on x86-64 currently.
You have been warned.
Say Y here if you are feeling brave and building a kernel for a
desktop, embedded or real-time system. Say N if you are unsure.
config PREEMPT_BKL
bool "Preempt The Big Kernel Lock"
depends on PREEMPT
default y
help
This option reduces the latency of the kernel by making the
big kernel lock preemptible.
Say Y here if you are building a kernel for a desktop system.
Say N if you are unsure.
config SCHED_SMT
bool "SMT (Hyperthreading) scheduler support"
depends on SMP
......@@ -244,6 +217,8 @@ config SCHED_SMT
cost of slightly increased overhead in some places. If unsure say
N here.
source "kernel/Kconfig.preempt"
config K8_NUMA
bool "K8 NUMA support"
select NUMA
......
config PREEMPT
bool "Preemptible Kernel"
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.
config PREEMPT_BKL
bool "Preempt The Big Kernel Lock"
depends on PREEMPT
default y
help
This option reduces the latency of the kernel by making the
big kernel lock preemptible.
Say Y here if you are building a kernel for a desktop system.
Say N if you are unsure.
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment