Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / kernel / Kconfig.preempt

diff --git a/kernel/kernel/Kconfig.preempt b/kernel/kernel/Kconfig.preempt
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+config PREEMPT
+       bool
+       select PREEMPT_COUNT
+
+config PREEMPT_RT_BASE
+       bool
+       select PREEMPT
+
+config HAVE_PREEMPT_LAZY
+       bool
+
+config PREEMPT_LAZY
+       def_bool y if HAVE_PREEMPT_LAZY && PREEMPT_RT_FULL
+
+choice
+       prompt "Preemption Model"
+       default PREEMPT_NONE
+
+config PREEMPT_NONE
+       bool "No Forced Preemption (Server)"
+       help
+         This is the traditional Linux preemption model, geared towards
+         throughput. It will still provide good latencies most of the
+         time, but there are no guarantees and occasional longer delays
+         are possible.
+
+         Select this option if you are building a kernel for a server or
+         scientific/computation system, or if you want to maximize the
+         raw processing power of the kernel, irrespective of scheduling
+         latencies.
+
+config PREEMPT_VOLUNTARY
+       bool "Voluntary Kernel Preemption (Desktop)"
+       help
+         This option reduces the latency of the kernel by adding more
+         "explicit preemption points" to the kernel code. These new
+         preemption points have been selected to reduce the maximum
+         latency of rescheduling, providing faster application reactions,
+         at the cost of slightly lower throughput.
+
+         This allows reaction to interactive events by allowing a
+         low priority process to voluntarily preempt itself even if it
+         is in kernel mode executing a system call. This allows
+         applications to run more 'smoothly' even when the system is
+         under load.
+
+         Select this if you are building a kernel for a desktop system.
+
+config PREEMPT__LL
+       bool "Preemptible Kernel (Low-Latency Desktop)"
+       select PREEMPT
+       select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK
+       help
+         This option reduces the latency of the kernel by making
+         all kernel code (that is not executing in a critical section)
+         preemptible.  This allows reaction to interactive events by
+         permitting a low priority process to be preempted involuntarily
+         even if it is in kernel mode executing a system call and would
+         otherwise not be about to reach a natural preemption point.
+         This allows applications to run more 'smoothly' even when the
+         system is under load, at the cost of slightly lower throughput
+         and a slight runtime overhead to kernel code.
+
+         Select this if you are building a kernel for a desktop or
+         embedded system with latency requirements in the milliseconds
+         range.
+
+config PREEMPT_RTB
+       bool "Preemptible Kernel (Basic RT)"
+       select PREEMPT_RT_BASE
+       help
+         This option is basically the same as (Low-Latency Desktop) but
+         enables changes which are preliminary for the full preemptible
+         RT kernel.
+
+config PREEMPT_RT_FULL
+       bool "Fully Preemptible Kernel (RT)"
+       depends on IRQ_FORCED_THREADING
+       select PREEMPT_RT_BASE
+       select PREEMPT_RCU
+       help
+         All and everything
+
+endchoice
+
+config PREEMPT_COUNT
+       bool
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