[tip:sched/urgent] sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT
Commit-ID: a50a3f4b6a313dc76912bd4ad3b8b4f4b479c801 Gitweb: https://git.kernel.org/tip/a50a3f4b6a313dc76912bd4ad3b8b4f4b479c801 Author: Thomas Gleixner AuthorDate: Wed, 17 Jul 2019 22:01:49 +0200 Committer: Ingo Molnar CommitDate: Thu, 18 Jul 2019 23:10:57 +0200 sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT Add a new entry to the preemption menu which enables the real-time support for the kernel. The choice is only enabled when an architecture supports it. It selects PREEMPT as the RT features depend on it. To achieve that the existing PREEMPT choice is renamed to PREEMPT_LL which select PREEMPT as well. No functional change. Signed-off-by: Thomas Gleixner Acked-by: Paul E. McKenney Acked-by: Steven Rostedt (VMware) Acked-by: Clark Williams Acked-by: Daniel Bristot de Oliveira Acked-by: Frederic Weisbecker Acked-by: Peter Zijlstra (Intel) Acked-by: Marc Zyngier Acked-by: Daniel Wagner Acked-by: Luis Claudio R. Goncalves Acked-by: Julia Cartwright Acked-by: Tom Zanussi Acked-by: Gratian Crisan Acked-by: Sebastian Siewior Cc: Andrew Morton Cc: Christoph Hellwig Cc: Greg Kroah-Hartman Cc: Linus Torvalds Cc: Lukas Bulwahn Cc: Mike Galbraith Cc: Tejun Heo Link: http://lkml.kernel.org/r/alpine.deb.2.21.1907172200190.1...@nanos.tec.linutronix.de Signed-off-by: Ingo Molnar --- arch/Kconfig | 3 +++ kernel/Kconfig.preempt | 25 +++-- 2 files changed, 26 insertions(+), 2 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index c47b328eada0..ada51f36bd5d 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -801,6 +801,9 @@ config ARCH_NO_COHERENT_DMA_MMAP config ARCH_NO_PREEMPT bool +config ARCH_SUPPORTS_RT + bool + config CPU_NO_EFFICIENT_FFS def_bool n diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt index dc0b682ec2d9..fc020c09b7e8 100644 --- a/kernel/Kconfig.preempt +++ b/kernel/Kconfig.preempt @@ -35,10 +35,10 @@ config PREEMPT_VOLUNTARY Select this if you are building a kernel for a desktop system. -config PREEMPT +config PREEMPT_LL bool "Preemptible Kernel (Low-Latency Desktop)" depends on !ARCH_NO_PREEMPT - select PREEMPT_COUNT + select PREEMPT select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK help This option reduces the latency of the kernel by making @@ -55,7 +55,28 @@ config PREEMPT embedded system with latency requirements in the milliseconds range. +config PREEMPT_RT + bool "Fully Preemptible Kernel (Real-Time)" + depends on EXPERT && ARCH_SUPPORTS_RT + select PREEMPT + help + This option turns the kernel into a real-time kernel by replacing + various locking primitives (spinlocks, rwlocks, etc.) with + preemptible priority-inheritance aware variants, enforcing + interrupt threading and introducing mechanisms to break up long + non-preemptible sections. This makes the kernel, except for very + low level and critical code pathes (entry code, scheduler, low + level interrupt handling) fully preemptible and brings most + execution contexts under scheduler control. + + Select this if you are building a kernel for systems which + require real-time guarantees. + endchoice config PREEMPT_COUNT bool + +config PREEMPT + bool + select PREEMPT_COUNT
[tip:sched/urgent] sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT
Commit-ID: a003296b7a97dedccb0c35c4c1e44e088050b8c4 Gitweb: https://git.kernel.org/tip/a003296b7a97dedccb0c35c4c1e44e088050b8c4 Author: Thomas Gleixner AuthorDate: Wed, 17 Jul 2019 22:01:49 +0200 Committer: Ingo Molnar CommitDate: Thu, 18 Jul 2019 19:47:11 +0200 sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT Add a new entry to the preemption menu which enables the real-time support for the kernel. The choice is only enabled when an architecture supports it. It selects PREEMPT as the RT features depend on it. To achieve that the existing PREEMPT choice is renamed to PREEMPT_LL which select PREEMPT as well. No functional change. Signed-off-by: Thomas Gleixner Acked-by: Paul E. McKenney Acked-by: Steven Rostedt (VMware) Acked-by: Clark Williams Acked-by: Daniel Bristot de Oliveira Acked-by: Frederic Weisbecker Acked-by: Peter Zijlstra (Intel) Acked-by: Marc Zyngier Acked-by: Daniel Wagner Acked-by: Luis Claudio R. Goncalves Acked-by: Julia Cartwright Cc: Andrew Morton Cc: Christoph Hellwig Cc: Clark Williams Cc: Gratian Crisan Cc: Greg Kroah-Hartman Cc: Linus Torvalds Cc: Lukas Bulwahn Cc: Mike Galbraith Cc: Paul McKenney Cc: Peter Zijlstra Cc: Sebastian Siewior Cc: Tejun Heo Cc: Tom Zanussi Link: http://lkml.kernel.org/r/alpine.deb.2.21.1907172200190.1...@nanos.tec.linutronix.de Signed-off-by: Ingo Molnar --- arch/Kconfig | 3 +++ kernel/Kconfig.preempt | 25 +++-- 2 files changed, 26 insertions(+), 2 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index c47b328eada0..ada51f36bd5d 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -801,6 +801,9 @@ config ARCH_NO_COHERENT_DMA_MMAP config ARCH_NO_PREEMPT bool +config ARCH_SUPPORTS_RT + bool + config CPU_NO_EFFICIENT_FFS def_bool n diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt index dc0b682ec2d9..fc020c09b7e8 100644 --- a/kernel/Kconfig.preempt +++ b/kernel/Kconfig.preempt @@ -35,10 +35,10 @@ config PREEMPT_VOLUNTARY Select this if you are building a kernel for a desktop system. -config PREEMPT +config PREEMPT_LL bool "Preemptible Kernel (Low-Latency Desktop)" depends on !ARCH_NO_PREEMPT - select PREEMPT_COUNT + select PREEMPT select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK help This option reduces the latency of the kernel by making @@ -55,7 +55,28 @@ config PREEMPT embedded system with latency requirements in the milliseconds range. +config PREEMPT_RT + bool "Fully Preemptible Kernel (Real-Time)" + depends on EXPERT && ARCH_SUPPORTS_RT + select PREEMPT + help + This option turns the kernel into a real-time kernel by replacing + various locking primitives (spinlocks, rwlocks, etc.) with + preemptible priority-inheritance aware variants, enforcing + interrupt threading and introducing mechanisms to break up long + non-preemptible sections. This makes the kernel, except for very + low level and critical code pathes (entry code, scheduler, low + level interrupt handling) fully preemptible and brings most + execution contexts under scheduler control. + + Select this if you are building a kernel for systems which + require real-time guarantees. + endchoice config PREEMPT_COUNT bool + +config PREEMPT + bool + select PREEMPT_COUNT
[tip:sched/urgent] sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT
Commit-ID: 2c2ffb925b368a1f00d4ddcc837f830394861d6c Gitweb: https://git.kernel.org/tip/2c2ffb925b368a1f00d4ddcc837f830394861d6c Author: Thomas Gleixner AuthorDate: Wed, 17 Jul 2019 22:01:49 +0200 Committer: Ingo Molnar CommitDate: Thu, 18 Jul 2019 14:53:32 +0200 sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT Add a new entry to the preemption menu which enables the real-time support for the kernel. The choice is only enabled when an architecture supports it. It selects PREEMPT as the RT features depend on it. To achieve that the existing PREEMPT choice is renamed to PREEMPT_LL which select PREEMPT as well. No functional change. Signed-off-by: Thomas Gleixner Acked-by: Paul E. McKenney Acked-by: Steven Rostedt (VMware) Acked-by: Clark Williams Acked-by: Daniel Bristot de Oliveira Acked-by: Frederic Weisbecker Acked-by: Peter Zijlstra (Intel) Acked-by: Marc Zyngier Acked-by: Daniel Wagner Acked-by: Luis Claudio R. Goncalves Cc: Andrew Morton Cc: Christoph Hellwig Cc: Clark Williams Cc: Gratian Crisan Cc: Greg Kroah-Hartman Cc: Julia Cartwright Cc: Linus Torvalds Cc: Lukas Bulwahn Cc: Mike Galbraith Cc: Paul McKenney Cc: Peter Zijlstra Cc: Sebastian Siewior Cc: Tejun Heo Cc: Tom Zanussi Link: http://lkml.kernel.org/r/alpine.deb.2.21.1907172200190.1...@nanos.tec.linutronix.de Signed-off-by: Ingo Molnar --- arch/Kconfig | 3 +++ kernel/Kconfig.preempt | 25 +++-- 2 files changed, 26 insertions(+), 2 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index c47b328eada0..ada51f36bd5d 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -801,6 +801,9 @@ config ARCH_NO_COHERENT_DMA_MMAP config ARCH_NO_PREEMPT bool +config ARCH_SUPPORTS_RT + bool + config CPU_NO_EFFICIENT_FFS def_bool n diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt index dc0b682ec2d9..fc020c09b7e8 100644 --- a/kernel/Kconfig.preempt +++ b/kernel/Kconfig.preempt @@ -35,10 +35,10 @@ config PREEMPT_VOLUNTARY Select this if you are building a kernel for a desktop system. -config PREEMPT +config PREEMPT_LL bool "Preemptible Kernel (Low-Latency Desktop)" depends on !ARCH_NO_PREEMPT - select PREEMPT_COUNT + select PREEMPT select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK help This option reduces the latency of the kernel by making @@ -55,7 +55,28 @@ config PREEMPT embedded system with latency requirements in the milliseconds range. +config PREEMPT_RT + bool "Fully Preemptible Kernel (Real-Time)" + depends on EXPERT && ARCH_SUPPORTS_RT + select PREEMPT + help + This option turns the kernel into a real-time kernel by replacing + various locking primitives (spinlocks, rwlocks, etc.) with + preemptible priority-inheritance aware variants, enforcing + interrupt threading and introducing mechanisms to break up long + non-preemptible sections. This makes the kernel, except for very + low level and critical code pathes (entry code, scheduler, low + level interrupt handling) fully preemptible and brings most + execution contexts under scheduler control. + + Select this if you are building a kernel for systems which + require real-time guarantees. + endchoice config PREEMPT_COUNT bool + +config PREEMPT + bool + select PREEMPT_COUNT
