From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH RFC 2/6] x86/hyper-v: add a function to read both TSC
 and TSC page value simulateneously
Date: Fri, 1 Dec 2017 09:29:04 -0800
Message-ID: <20171201092904.30d9831f@xeon-e3>
References: <20171201131321.918-1-vkuznets@redhat.com>
 <20171201131321.918-3-vkuznets@redhat.com>
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Cc: Stephen Hemminger <sthemmin@microsoft.com>, kvm@vger.kernel.org,
 Radim =?UTF-8?B?S3LEjW3DocWZ?= <rkrcmar@redhat.com>,
 Haiyang Zhang <haiyangz@microsoft.com>, x86@kernel.org,
 linux-kernel@vger.kernel.org, Paolo Bonzini <pbonzini@redhat.com>,
 Ingo Molnar <mingo@redhat.com>, Andy Lutomirski <luto@kernel.org>,
 "H. Peter Anvin" <hpa@zytor.com>, devel@linuxdriverproject.org,
 Thomas Gleixner <tglx@linutronix.de>
To: Vitaly Kuznetsov <vkuznets@redhat.com>
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On Fri,  1 Dec 2017 14:13:17 +0100
Vitaly Kuznetsov <vkuznets@redhat.com> wrote:

> +
> +static inline u64 hv_read_tsc_page_tsc(const struct ms_hyperv_tsc_page *tsc_pg,
> +				       u64 *cur_tsc)
> +{
> +	*cur_tsc = rdtsc();
> +
> +	return cur_tsc;

Why do return and setting by reference. Looks like an ugly API.