diff options
| -rw-r--r-- | kernel/time/Kconfig | 10 | ||||
| -rw-r--r-- | kernel/time/tick-sched.c | 23 |
2 files changed, 31 insertions, 2 deletions
diff --git a/kernel/time/Kconfig b/kernel/time/Kconfig index 358d601a4fec..99c3f13dd478 100644 --- a/kernel/time/Kconfig +++ b/kernel/time/Kconfig @@ -128,6 +128,16 @@ config NO_HZ_FULL endchoice +config NO_HZ_FULL_ALL + bool "Full dynticks system on all CPUs by default" + depends on NO_HZ_FULL + help + If the user doesn't pass the nohz_full boot option to + define the range of full dynticks CPUs, consider that all + CPUs in the system are full dynticks by default. + Note the boot CPU will still be kept outside the range to + handle the timekeeping duty. + config NO_HZ bool "Old Idle dynticks config" depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index d71a5f2bd7b2..a76e09044f9f 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -203,12 +203,31 @@ static int __cpuinit tick_nohz_cpu_down_callback(struct notifier_block *nfb, */ static char __initdata nohz_full_buf[NR_CPUS + 1]; +static int tick_nohz_init_all(void) +{ + int err = -1; + +#ifdef CONFIG_NO_HZ_FULL_ALL + if (!alloc_cpumask_var(&nohz_full_mask, GFP_KERNEL)) { + pr_err("NO_HZ: Can't allocate full dynticks cpumask\n"); + return err; + } + err = 0; + cpumask_setall(nohz_full_mask); + cpumask_clear_cpu(smp_processor_id(), nohz_full_mask); + have_nohz_full_mask = true; +#endif + return err; +} + void __init tick_nohz_init(void) { int cpu; - if (!have_nohz_full_mask) - return; + if (!have_nohz_full_mask) { + if (tick_nohz_init_all() < 0) + return; + } cpu_notifier(tick_nohz_cpu_down_callback, 0); |