The function traverses stimer_pending_bitmap n a for-loop bit by bit. We can do it faster by using atomic find_and_set_bit(). While here, refactor the logic by decreasing indentation level and dropping 2nd check for stimer->config.enable. Signed-off-by: Yury Norov <yury.norov@xxxxxxxxx> --- arch/x86/kvm/hyperv.c | 39 +++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 20 deletions(-) diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 238afd7335e4..460e300b558b 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -870,27 +870,26 @@ void kvm_hv_process_stimers(struct kvm_vcpu *vcpu) if (!hv_vcpu) return; - for (i = 0; i < ARRAY_SIZE(hv_vcpu->stimer); i++) - if (test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap)) { - stimer = &hv_vcpu->stimer[i]; - if (stimer->config.enable) { - exp_time = stimer->exp_time; - - if (exp_time) { - time_now = - get_time_ref_counter(vcpu->kvm); - if (time_now >= exp_time) - stimer_expiration(stimer); - } - - if ((stimer->config.enable) && - stimer->count) { - if (!stimer->msg_pending) - stimer_start(stimer); - } else - stimer_cleanup(stimer); - } + for_each_test_and_clear_bit(i, hv_vcpu->stimer_pending_bitmap, + ARRAY_SIZE(hv_vcpu->stimer)) { + stimer = &hv_vcpu->stimer[i]; + if (!stimer->config.enable) + continue; + + exp_time = stimer->exp_time; + + if (exp_time) { + time_now = get_time_ref_counter(vcpu->kvm); + if (time_now >= exp_time) + stimer_expiration(stimer); } + + if (stimer->count) { + if (!stimer->msg_pending) + stimer_start(stimer); + } else + stimer_cleanup(stimer); + } } void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu) -- 2.39.2