[PATCH 02/17] cpumask: Introduce cpu_paravirt_mask
From: Shrikanth Hegde <sshegde@linux.ibm.com>
Date: 2025-11-19 12:45:30
Also in:
lkml
Subsystem:
bitmap api, scheduler, the rest · Maintainers:
Yury Norov, Ingo Molnar, Peter Zijlstra, Juri Lelli, Vincent Guittot, Linus Torvalds
This patch does - Declare and Define cpu_paravirt_mask. - Get/Set helpers for it. Values are set by arch code and consumed by the scheduler. Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com> --- include/linux/cpumask.h | 20 ++++++++++++++++++++ kernel/sched/core.c | 5 +++++ 2 files changed, 25 insertions(+)
diff --git a/include/linux/cpumask.h b/include/linux/cpumask.h
index ff8f41ab7ce6..079903851341 100644
--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h@@ -1270,6 +1270,26 @@ static __always_inline bool cpu_dying(unsigned int cpu) #endif /* NR_CPUS > 1 */ +/* + * All related wrappers kept together to avoid too many ifdefs + * See Documentation/scheduler/sched-arch.rst for details + */ +#ifdef CONFIG_PARAVIRT +extern struct cpumask __cpu_paravirt_mask; +#define cpu_paravirt_mask ((const struct cpumask *)&__cpu_paravirt_mask) +#define set_cpu_paravirt(cpu, paravirt) assign_cpu((cpu), &__cpu_paravirt_mask, (paravirt)) + +static __always_inline bool cpu_paravirt(unsigned int cpu) +{ + return cpumask_test_cpu(cpu, cpu_paravirt_mask); +} +#else +static __always_inline bool cpu_paravirt(unsigned int cpu) +{ + return false; +} +#endif + #define cpu_is_offline(cpu) unlikely(!cpu_online(cpu)) #if NR_CPUS <= BITS_PER_LONG
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 9f10cfbdc228..40db5e659994 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c@@ -10852,3 +10852,8 @@ void sched_change_end(struct sched_change_ctx *ctx) p->sched_class->prio_changed(rq, p, ctx->prio); } } + +#ifdef CONFIG_PARAVIRT +struct cpumask __cpu_paravirt_mask __read_mostly; +EXPORT_SYMBOL(__cpu_paravirt_mask); +#endif
--
2.47.3