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Date:   Mon, 4 Dec 2023 08:00:26 -0800
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Subject: Re: [PATCH v2 13/35] KVM: x86: hyper-v: optimize and cleanup kvm_hv_process_stimers()
From:   Sean Christopherson <seanjc@google.com>
To:     Vitaly Kuznetsov <vkuznets@redhat.com>
Cc:     Yury Norov <yury.norov@gmail.com>, linux-kernel@vger.kernel.org,
        Paolo Bonzini <pbonzini@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, kvm@vger.kernel.org,
        Jan Kara <jack@suse.cz>,
        Mirsad Todorovac <mirsad.todorovac@alu.unizg.hr>,
        Matthew Wilcox <willy@infradead.org>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Maxim Kuvyrkov <maxim.kuvyrkov@linaro.org>,
        Alexey Klimov <klimov.linux@gmail.com>,
        Bart Van Assche <bvanassche@acm.org>,
        Sergey Shtylyov <s.shtylyov@omp.ru>
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On Mon, Dec 04, 2023, Vitaly Kuznetsov wrote:
> > -	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)) {

Another nit, please align the indendation:

	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->config.enable && stimer->count) {
> > +			if (!stimer->msg_pending)
> > +				stimer_start(stimer);
> > +		} else
> > +			stimer_cleanup(stimer);
> 
> Minor nitpick: it's better (and afair required by coding style) to use
> '{}' for both branches here:

Yeah, it's a hard requirement in KVM x86.

> 
> 	if (stimer->config.enable && stimer->count) {
> 		if (!stimer->msg_pending)
> 			stimer_start(stimer);
> 	} else {
> 		stimer_cleanup(stimer);
> 	}
> 
> > +	}
> >  }
> >  
> >  void kvm_hv_vcpu_uninit(struct kvm_vcpu *vcpu)
> 
> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
> 
> -- 
> Vitaly
>