Commit 4c470317 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull scheduler fixes from Thomas Gleixner:
 "Three patches addressing the fallout of the CPU_ISOLATION changes
  especially with NO_HZ_FULL plus documentation of boot parameter
  dependency"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/isolation: Document boot parameters dependency on CONFIG_CPU_ISOLATION=y
  sched/isolation: Enable CONFIG_CPU_ISOLATION=y by default
  sched/isolation: Make CONFIG_NO_HZ_FULL select CONFIG_CPU_ISOLATION
parents e7c632fc d94d1053

Documentation/admin-guide/kernel-parameters.rst

+1 −0
Original line number Diff line number Diff line
@@ -109,6 +109,7 @@ parameter is applicable:: 
	IPV6	IPv6 support is enabled.

	ISAPNP	ISA PnP code is enabled.

	ISDN	Appropriate ISDN support is enabled.

	ISOL	CPU Isolation is enabled.

	JOY	Appropriate joystick support is enabled.

	KGDB	Kernel debugger support is enabled.

	KVM	Kernel Virtual Machine support is enabled.

Documentation/admin-guide/kernel-parameters.txt

+2 −2
Original line number Diff line number Diff line
@@ -1737,7 +1737,7 @@ 
	isapnp=		[ISAPNP]

			Format: <RDP>,<reset>,<pci_scan>,<verbosity>



	isolcpus=	[KNL,SMP] Isolate a given set of CPUs from disturbance.

	isolcpus=	[KNL,SMP,ISOL] Isolate a given set of CPUs from disturbance.

			[Deprecated - use cpusets instead]

			Format: [flag-list,]<cpu-list>
@@ -2662,7 +2662,7 @@ 
			Valid arguments: on, off

			Default: on



	nohz_full=	[KNL,BOOT]

	nohz_full=	[KNL,BOOT,SMP,ISOL]

			The argument is a cpu list, as described above.

			In kernels built with CONFIG_NO_HZ_FULL=y, set

			the specified list of CPUs whose tick will be stopped

init/Kconfig

+5 −1
Original line number Diff line number Diff line
@@ -461,10 +461,14 @@ endmenu # "CPU/Task time and stats accounting" 


config CPU_ISOLATION

	bool "CPU isolation"

	default y

	help

	  Make sure that CPUs running critical tasks are not disturbed by

	  any source of "noise" such as unbound workqueues, timers, kthreads...

	  Unbound jobs get offloaded to housekeeping CPUs.

	  Unbound jobs get offloaded to housekeeping CPUs. This is driven by

	  the "isolcpus=" boot parameter.



	  Say Y if unsure.



source "kernel/rcu/Kconfig"

kernel/time/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -95,6 +95,7 @@ config NO_HZ_FULL 
	select RCU_NOCB_CPU

	select VIRT_CPU_ACCOUNTING_GEN

	select IRQ_WORK

	select CPU_ISOLATION

	help

	 Adaptively try to shutdown the tick whenever possible, even when

	 the CPU is running tasks. Typically this requires running a single

CRA Git | Maintained and supported by SUSTech CRA and CCSE