All of lore.kernel.org
 help / color / mirror / Atom feed
From: Paolo Bonzini <pbonzini@redhat.com>
To: Sean Christopherson <seanjc@google.com>,
	Wanpeng Li <kernellwp@gmail.com>
Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	Wanpeng Li <wanpengli@tencent.com>,
	Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>
Subject: Re: [PATCH] KVM: LAPIC: Narrow down the timer fastpath to tscdeadline timer
Date: Tue, 10 May 2022 16:18:26 +0200	[thread overview]
Message-ID: <80ddc8a2-41c6-4e12-62f9-7acd51cabdb7@redhat.com> (raw)
In-Reply-To: <YnpzetR/B3nXVJxu@google.com>

On 5/10/22 16:15, Sean Christopherson wrote:
>>   
>> -static fastpath_t handle_fastpath_preemption_timer(struct kvm_vcpu *vcpu)
>> +static bool __handle_preemption_timer(struct kvm_vcpu *vcpu)
>>   {
>>   	struct vcpu_vmx *vmx = to_vmx(vcpu);
>>   
>>   	if (!vmx->req_immediate_exit &&
>>   	    !unlikely(vmx->loaded_vmcs->hv_timer_soft_disabled)) {
>>   		kvm_lapic_expired_hv_timer(vcpu);
>> -		return EXIT_FASTPATH_REENTER_GUEST;
>> +		return true;
>>   	}
>>   
>> +	return false;
> It's a bit odd for the non-fastpath case, but I'd prefer to return fastpath_t
> instead of a bool from the inner helper, e.g.
> 

Yeah, enum > bool almost always (or negative errno).  But I also agree 
that using the fast path for periodic or oneshot timers is not 
inherently a bad idea.

Paolo


      reply	other threads:[~2022-05-10 14:54 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-05-06  9:47 [PATCH] KVM: LAPIC: Narrow down the timer fastpath to tscdeadline timer Wanpeng Li
2022-05-10 14:15 ` Sean Christopherson
2022-05-10 14:18   ` Paolo Bonzini [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=80ddc8a2-41c6-4e12-62f9-7acd51cabdb7@redhat.com \
    --to=pbonzini@redhat.com \
    --cc=jmattson@google.com \
    --cc=joro@8bytes.org \
    --cc=kernellwp@gmail.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=seanjc@google.com \
    --cc=vkuznets@redhat.com \
    --cc=wanpengli@tencent.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.