diff --git a/arch/loongarch/include/asm/qspinlock.h b/arch/loongarch/include/asm/qspinlock.h index e76d3aa1e1eb..66244801db67 100644 --- a/arch/loongarch/include/asm/qspinlock.h +++ b/arch/loongarch/include/asm/qspinlock.h @@ -34,6 +34,10 @@ static inline bool virt_spin_lock(struct qspinlock *lock) return true; } +#define vcpu_is_preempted vcpu_is_preempted + +bool vcpu_is_preempted(int cpu); + #endif /* CONFIG_PARAVIRT */ #include diff --git a/arch/loongarch/kernel/paravirt.c b/arch/loongarch/kernel/paravirt.c index b1b51f920b23..7f1561906e10 100644 --- a/arch/loongarch/kernel/paravirt.c +++ b/arch/loongarch/kernel/paravirt.c @@ -12,6 +12,7 @@ static int has_steal_clock; struct static_key paravirt_steal_enabled; struct static_key paravirt_steal_rq_enabled; static DEFINE_PER_CPU(struct kvm_steal_time, steal_time) __aligned(64); +static DEFINE_STATIC_KEY_FALSE(virt_preempt_key); DEFINE_STATIC_KEY_FALSE(virt_spin_lock_key); static u64 native_steal_clock(int cpu) @@ -267,6 +268,18 @@ static int pv_time_cpu_down_prepare(unsigned int cpu) return 0; } + +bool vcpu_is_preempted(int cpu) +{ + struct kvm_steal_time *src; + + if (!static_branch_unlikely(&virt_preempt_key)) + return false; + + src = &per_cpu(steal_time, cpu); + return !!(src->preempted & KVM_VCPU_PREEMPTED); +} +EXPORT_SYMBOL(vcpu_is_preempted); #endif static void pv_cpu_reboot(void *unused) @@ -308,6 +321,9 @@ int __init pv_time_init(void) pr_err("Failed to install cpu hotplug callbacks\n"); return r; } + + if (kvm_para_has_feature(KVM_FEATURE_PREEMPT)) + static_branch_enable(&virt_preempt_key); #endif static_call_update(pv_steal_clock, paravt_steal_clock); @@ -318,7 +334,10 @@ int __init pv_time_init(void) static_key_slow_inc(¶virt_steal_rq_enabled); #endif - pr_info("Using paravirt steal-time\n"); + if (static_key_enabled(&virt_preempt_key)) + pr_info("Using paravirt steal-time with preempt enabled\n"); + else + pr_info("Using paravirt steal-time with preempt disabled\n"); return 0; }