Almost all architectures include it. Add a ARCH_NO_PREEMPT symbol to disable preempt support for alpha, hexagon, non-coldfire m68k and user mode Linux. Signed-off-by: Christoph Hellwig <hch@xxxxxx> --- arch/Kconfig | 3 +++ arch/alpha/Kconfig | 1 + arch/arc/Kconfig | 2 -- arch/arm/Kconfig | 2 -- arch/arm64/Kconfig | 1 - arch/c6x/Kconfig | 2 -- arch/h8300/Kconfig | 6 ------ arch/hexagon/Kconfig | 1 + arch/ia64/Kconfig | 2 -- arch/m68k/Kconfig | 5 +---- arch/microblaze/Kconfig | 2 -- arch/mips/Kconfig | 2 -- arch/nds32/Kconfig | 1 - arch/nios2/Kconfig | 2 -- arch/openrisc/Kconfig | 1 - arch/parisc/Kconfig | 1 - arch/powerpc/Kconfig | 1 - arch/riscv/Kconfig | 2 -- arch/s390/Kconfig | 2 -- arch/sh/Kconfig | 2 -- arch/sparc/Kconfig | 2 -- arch/um/Kconfig | 1 + arch/unicore32/Kconfig | 2 -- arch/x86/Kconfig | 2 -- arch/xtensa/Kconfig | 2 -- init/Kconfig | 1 + kernel/Kconfig.preempt | 2 ++ 27 files changed, 10 insertions(+), 43 deletions(-) diff --git a/arch/Kconfig b/arch/Kconfig index 09a561a70168..cddd0faae4cb 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -881,6 +881,9 @@ config COMPAT_32BIT_TIME config ARCH_NO_COHERENT_DMA_MMAP bool +config ARCH_NO_PREEMPT + bool + config CPU_NO_EFFICIENT_FFS def_bool n diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig index e4334f017f8e..5b4f88363453 100644 --- a/arch/alpha/Kconfig +++ b/arch/alpha/Kconfig @@ -4,6 +4,7 @@ config ALPHA default y select ARCH_MIGHT_HAVE_PC_PARPORT select ARCH_MIGHT_HAVE_PC_SERIO + select ARCH_NO_PREEMPT select ARCH_USE_CMPXCHG_LOCKREF select HAVE_AOUT select HAVE_IDE diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 85b56dee4efa..24bf1408ae59 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -545,8 +545,6 @@ config ARC_BUILTIN_DTB_NAME Set the name of the DTB to embed in the vmlinux binary Leaving it blank selects the minimal "skeleton" dtb -source "kernel/Kconfig.preempt" - endmenu # "ARC Architecture Configuration" config FORCE_MAX_ZONEORDER diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 9aaa23c25374..1b1c21519039 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1481,8 +1481,6 @@ config ARCH_NR_GPIO If unsure, leave the default value. -source kernel/Kconfig.preempt - config HZ_FIXED int default 200 if ARCH_EBSA110 diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 07d457ec417a..daf59d363dd3 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -752,7 +752,6 @@ config HOLES_IN_ZONE def_bool y depends on NUMA -source kernel/Kconfig.preempt source kernel/Kconfig.hz config ARCH_SUPPORTS_DEBUG_PAGEALLOC diff --git a/arch/c6x/Kconfig b/arch/c6x/Kconfig index 904b3375331e..a641b0bf1611 100644 --- a/arch/c6x/Kconfig +++ b/arch/c6x/Kconfig @@ -110,8 +110,6 @@ config KERNEL_RAM_BASE_ADDRESS default 0xe0000000 if SOC_TMS320C6472 default 0x80000000 -source "kernel/Kconfig.preempt" - source "kernel/Kconfig.hz" endmenu diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig index c16e7cf732f7..5e89d40be8cd 100644 --- a/arch/h8300/Kconfig +++ b/arch/h8300/Kconfig @@ -49,9 +49,3 @@ config NR_CPUS default 1 source "arch/h8300/Kconfig.cpu" - -menu "Kernel Features" - -source "kernel/Kconfig.preempt" - -endmenu diff --git a/arch/hexagon/Kconfig b/arch/hexagon/Kconfig index fcdb6d9fcecc..89a4b22f34d9 100644 --- a/arch/hexagon/Kconfig +++ b/arch/hexagon/Kconfig @@ -4,6 +4,7 @@ comment "Linux Kernel Configuration for Hexagon" config HEXAGON def_bool y + select ARCH_NO_PREEMPT select HAVE_OPROFILE # Other pending projects/to-do items. # select HAVE_REGS_AND_STACK_ACCESS_API diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index 34a8d24cffea..86bd377bc7c0 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -364,8 +364,6 @@ config FORCE_CPEI_RETARGET This option it useful to enable this feature on older BIOS's as well. You can also enable this by using boot command line option force_cpei=1. -source "kernel/Kconfig.preempt" - config ARCH_SELECT_MEMORY_MODEL def_bool y diff --git a/arch/m68k/Kconfig b/arch/m68k/Kconfig index cf41ad45513f..3e47f8df6504 100644 --- a/arch/m68k/Kconfig +++ b/arch/m68k/Kconfig @@ -4,6 +4,7 @@ config M68K default y select ARCH_MIGHT_HAVE_PC_PARPORT if ISA select ARCH_NO_COHERENT_DMA_MMAP if !MMU + select ARCH_NO_PREEMPT if !COLDFIRE select HAVE_IDE select HAVE_AOUT if MMU select HAVE_DEBUG_BUGVERBOSE @@ -129,10 +130,6 @@ endmenu menu "Kernel Features" -if COLDFIRE -source "kernel/Kconfig.preempt" -endif - endmenu if !MMU diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig index f4492e9478fe..6163a39ddeb6 100644 --- a/arch/microblaze/Kconfig +++ b/arch/microblaze/Kconfig @@ -87,8 +87,6 @@ source "arch/microblaze/Kconfig.platform" menu "Processor type and features" -source "kernel/Kconfig.preempt" - source "kernel/Kconfig.hz" config MMU diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index ab02824c3976..06a633eb9777 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -2818,8 +2818,6 @@ config HZ config SCHED_HRTICK def_bool HIGH_RES_TIMERS -source "kernel/Kconfig.preempt" - config KEXEC bool "Kexec system call" select KEXEC_CORE diff --git a/arch/nds32/Kconfig b/arch/nds32/Kconfig index d834061ba0ec..1d4248fa55e9 100644 --- a/arch/nds32/Kconfig +++ b/arch/nds32/Kconfig @@ -88,6 +88,5 @@ config NDS32_BUILTIN_DTB endmenu menu "Kernel Features" -source "kernel/Kconfig.preempt" source "kernel/Kconfig.hz" endmenu diff --git a/arch/nios2/Kconfig b/arch/nios2/Kconfig index 22d19febcc92..cbe1844b0657 100644 --- a/arch/nios2/Kconfig +++ b/arch/nios2/Kconfig @@ -47,8 +47,6 @@ config TRACE_IRQFLAGS_SUPPORT menu "Kernel features" -source "kernel/Kconfig.preempt" - source "kernel/Kconfig.hz" config FORCE_MAX_ZONEORDER diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig index c52cecd94d62..42e3a0f2afab 100644 --- a/arch/openrisc/Kconfig +++ b/arch/openrisc/Kconfig @@ -143,7 +143,6 @@ config SMP If you don't know what to do here, say N. source kernel/Kconfig.hz -source kernel/Kconfig.preempt config OPENRISC_NO_SPR_SR_DSX bool "use SPR_SR_DSX software emulation" if OR1K_1200 diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index d1dd56ea297b..89496aa318da 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -323,7 +323,6 @@ config NODES_SHIFT default "3" depends on NEED_MULTIPLE_NODES -source "kernel/Kconfig.preempt" source "kernel/Kconfig.hz" config COMPAT diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index c55e61302d57..1c10ff0406f2 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -393,7 +393,6 @@ config HIGHMEM depends on PPC32 source kernel/Kconfig.hz -source kernel/Kconfig.preempt config HUGETLB_PAGE_SIZE_VARIABLE bool diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 73c0e16793fa..a344980287a5 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -212,8 +212,6 @@ endmenu menu "Kernel type" -source "kernel/Kconfig.preempt" - source "kernel/Kconfig.hz" endmenu diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index ac8925766d0a..8441bd8f7d70 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -511,8 +511,6 @@ config SCHED_TOPOLOGY making when dealing with machines that have multi-threading, multiple cores or multiple books. -source kernel/Kconfig.preempt - source kernel/Kconfig.hz config KEXEC diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig index c8460330eff7..993f61a5961d 100644 --- a/arch/sh/Kconfig +++ b/arch/sh/Kconfig @@ -709,8 +709,6 @@ config HOTPLUG_CPU Say Y here to experiment with turning CPUs off and on. CPUs can be controlled through /sys/devices/system/cpu. -source "kernel/Kconfig.preempt" - config GUSA def_bool y depends on !SMP && SUPERH32 diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index 622695e8fa44..2d58c26bff9a 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -349,8 +349,6 @@ config SCHED_MC making when dealing with multi-core CPU chips at a cost of slightly increased overhead in some places. If unsure say N here. -source "kernel/Kconfig.preempt" - config CMDLINE_BOOL bool "Default bootloader kernel arguments" depends on SPARC64 diff --git a/arch/um/Kconfig b/arch/um/Kconfig index 2372b74711e1..dd4b67131105 100644 --- a/arch/um/Kconfig +++ b/arch/um/Kconfig @@ -6,6 +6,7 @@ config UML bool default y select ARCH_HAS_KCOV + select ARCH_NO_PREEMPT select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_SECCOMP_FILTER select HAVE_UID16 diff --git a/arch/unicore32/Kconfig b/arch/unicore32/Kconfig index 6bfaa4a910e1..60eae744d8fd 100644 --- a/arch/unicore32/Kconfig +++ b/arch/unicore32/Kconfig @@ -135,8 +135,6 @@ endmenu menu "Kernel Features" -source "kernel/Kconfig.preempt" - source "kernel/Kconfig.hz" config LEDS diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index fd3a4c77b028..41dbcff3074f 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1039,8 +1039,6 @@ config SCHED_MC_PRIO If unsure say Y here. -source "kernel/Kconfig.preempt" - config UP_LATE_INIT def_bool y depends on !SMP && X86_LOCAL_APIC diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index aae0e1800be7..801491e98890 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -173,8 +173,6 @@ config XTENSA_UNALIGNED_USER Say Y here to enable unaligned memory access in user space. -source "kernel/Kconfig.preempt" - config HAVE_SMP bool "System Supports SMP (MX)" depends on XTENSA_VARIANT_CUSTOM diff --git a/init/Kconfig b/init/Kconfig index 283f6bc796b1..29bbad9338d6 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -326,6 +326,7 @@ config AUDIT_TREE source "kernel/irq/Kconfig" source "kernel/time/Kconfig" +source "kernel/Kconfig.preempt" menu "CPU/Task time and stats accounting" diff --git a/kernel/Kconfig.preempt b/kernel/Kconfig.preempt index 3f9c97419f02..cd1655122ec0 100644 --- a/kernel/Kconfig.preempt +++ b/kernel/Kconfig.preempt @@ -18,6 +18,7 @@ config PREEMPT_NONE config PREEMPT_VOLUNTARY bool "Voluntary Kernel Preemption (Desktop)" + depends on !ARCH_NO_PREEMPT help This option reduces the latency of the kernel by adding more "explicit preemption points" to the kernel code. These new @@ -35,6 +36,7 @@ config PREEMPT_VOLUNTARY config PREEMPT bool "Preemptible Kernel (Low-Latency Desktop)" + depends on !ARCH_NO_PREEMPT select PREEMPT_COUNT select UNINLINE_SPIN_UNLOCK if !ARCH_INLINE_SPIN_UNLOCK help -- 2.18.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html