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Subject: Re: [PATCH 2/5] KVM: add KVM request variants without barrier
To: =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= <rkrcmar@redhat.com>,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org
References: <20170216160449.13094-1-rkrcmar@redhat.com>
 <20170216160449.13094-3-rkrcmar@redhat.com>
Cc: Andrew Jones <drjones@redhat.com>, Marc Zyngier <marc.zyngier@arm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        Cornelia Huck <cornelia.huck@de.ibm.com>,
        James Hogan <james.hogan@imgtec.com>,
        Paul Mackerras <paulus@ozlabs.org>,
        Christoffer Dall <christoffer.dall@linaro.org>
From: Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <f955cbce-5e64-1262-56eb-5c34fa0d69a4@redhat.com>
Date: Thu, 23 Feb 2017 11:57:43 +0100
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On 16/02/2017 17:04, Radim Krčmář wrote:
> +
> +static inline void __kvm_request_clear(unsigned req, struct kvm_vcpu *vcpu)
> +{
> +	test_bit(req, &vcpu->requests);
>  }

Are you sure? :)

Paolo

>  static inline bool kvm_request_test_and_clear(unsigned req, struct kvm_vcpu *vcpu)
>  {
> -	if (test_bit(req, &vcpu->requests)) {
> -		clear_bit(req, &vcpu->requests);
> +	if (__kvm_request_test(req, vcpu)) {
> +		__kvm_request_clear(req, vcpu);
>  
>  		/*
>  		 * Ensure the rest of the request is visible to
> --