Linus, please pull the latest sched-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched-urgent-for-linus Three patches addressing the fallout of the CPU_ISOLATION changes especially with NO_HZ_FULL plus documentation of boot parameter dependency. Thanks, tglx ------------------> Frederic Weisbecker (2): sched/isolation: Enable CONFIG_CPU_ISOLATION=y by default sched/isolation: Document boot parameters dependency on CONFIG_CPU_ISOLATION=y Paul E. McKenney (1): sched/isolation: Make CONFIG_NO_HZ_FULL select CONFIG_CPU_ISOLATION Documentation/admin-guide/kernel-parameters.rst | 1 + Documentation/admin-guide/kernel-parameters.txt | 4 ++-- init/Kconfig | 6 +++++- kernel/time/Kconfig | 1 + 4 files changed, 9 insertions(+), 3 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.rst b/Documentation/admin-guide/kernel-parameters.rst index b2598cc9834c..7242cbda15dd 100644 --- a/Documentation/admin-guide/kernel-parameters.rst +++ b/Documentation/admin-guide/kernel-parameters.rst @@ -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. diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 6571fbfdb2a1..168310707ec2 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -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 diff --git a/init/Kconfig b/init/Kconfig index 2934249fba46..690a381adee0 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -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" diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index e776fc8cc1df..f6b5f19223d6 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -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