diff options
| author | Bibo Mao <maobibo@loongson.cn> | 2023-12-19 10:48:27 +0800 |
|---|---|---|
| committer | Huacai Chen <chenhuacai@loongson.cn> | 2023-12-19 10:48:27 +0800 |
| commit | 161267320158920a601e40d83fdac60bcaa2acb5 (patch) | |
| tree | af655a4911e55c558a123814026ad071812feffc /arch/loongarch/kvm/timer.c | |
| parent | 7ab6fb505b2a7447c4a7237a12c59e3ad0c7298c (diff) | |
LoongArch: KVM: Remove SW timer switch when vcpu is halt polling
With halt-polling supported, there is checking for pending events or
interrupts when vcpu executes idle instruction. Pending interrupts
include injected SW interrupts and passthrough HW interrupts, such as
HW timer interrupts, since HW timer works still even if vcpu exists from
VM mode.
Since HW timer pending interrupt can be set directly with CSR status
register, and pending HW timer interrupt checking is used in vcpu block
checking function, it is not necessary to switch to SW timer during
halt-polling. This patch adds preemption disabling in function
kvm_cpu_has_pending_timer(), and removes SW timer switching in idle
instruction emulation function.
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Diffstat (limited to 'arch/loongarch/kvm/timer.c')
| -rw-r--r-- | arch/loongarch/kvm/timer.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/arch/loongarch/kvm/timer.c b/arch/loongarch/kvm/timer.c index 284bf553fefe..12d58040122d 100644 --- a/arch/loongarch/kvm/timer.c +++ b/arch/loongarch/kvm/timer.c @@ -155,11 +155,17 @@ static void _kvm_save_timer(struct kvm_vcpu *vcpu) */ hrtimer_cancel(&vcpu->arch.swtimer); hrtimer_start(&vcpu->arch.swtimer, expire, HRTIMER_MODE_ABS_PINNED); - } else + } else if (vcpu->stat.generic.blocking) { /* - * Inject timer interrupt so that hall polling can dectect and exit + * Inject timer interrupt so that halt polling can dectect and exit. + * VCPU is scheduled out already and sleeps in rcuwait queue and + * will not poll pending events again. kvm_queue_irq() is not enough, + * hrtimer swtimer should be used here. */ - kvm_queue_irq(vcpu, INT_TI); + expire = ktime_add_ns(ktime_get(), 10); + vcpu->arch.expire = expire; + hrtimer_start(&vcpu->arch.swtimer, expire, HRTIMER_MODE_ABS_PINNED); + } } /* |