From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH v2] KVM: x86: update masterclock values on TSC writes
Date: Wed, 05 Nov 2014 10:36:05 +0100
Message-ID: <5459EF85.5010206@redhat.com>
References: <20141104233044.GB29191@amt.cnet>
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Cc: kvm-devel <kvm@vger.kernel.org>
To: Marcelo Tosatti <mtosatti@redhat.com>
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On 05/11/2014 00:30, Marcelo Tosatti wrote:
> +	/*
> +	 * If the vcpus have matched TSCs and host clocksource is TSC,
> +	 * perform request to enable masterclock.
> +	 *
> +	 * If the masterclock is enabled, perform request to update
> +	 * masterclock values.
> +	 */
> +	if ((vcpus_matched && gtod->clock.vclock_mode == VCLOCK_TSC) ||
> +	     ka->use_master_clock)

This is not an explanation, it is a literal translation from C to
English. :)  Can you also explain the why, especially for the first half
of the condition?

Paolo