From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@qumranet.com>
Subject: Re: [PATCH 1/6] KVM: In kernel pit model
Date: Wed, 05 Mar 2008 08:54:06 +0200
Message-ID: <47CE438E.2090408@qumranet.com>
References: <200803041822.44757.sheng.yang@intel.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Cc: kvm-devel@lists.sourceforge.net
To: "Yang, Sheng" <sheng.yang@intel.com>
Return-path: <kvm-devel-bounces@lists.sourceforge.net>
In-Reply-To: <200803041822.44757.sheng.yang@intel.com>
List-Unsubscribe: <https://lists.sourceforge.net/lists/listinfo/kvm-devel>,
	<mailto:kvm-devel-request@lists.sourceforge.net?subject=unsubscribe>
List-Archive: <http://sourceforge.net/mailarchive/forum.php?forum_name=kvm-devel>
List-Post: <mailto:kvm-devel@lists.sourceforge.net>
List-Help: <mailto:kvm-devel-request@lists.sourceforge.net?subject=help>
List-Subscribe: <https://lists.sourceforge.net/lists/listinfo/kvm-devel>,
	<mailto:kvm-devel-request@lists.sourceforge.net?subject=subscribe>
Sender: kvm-devel-bounces@lists.sourceforge.net
Errors-To: kvm-devel-bounces@lists.sourceforge.net
List-Id: kvm.vger.kernel.org

Yang, Sheng wrote:
> +
> +static int pit_get_out(struct kvm *kvm, int channel)
> +{
> +	struct kvm_kpit_channel_state *c =
> +		&kvm->arch.vpit->pit_state.channels[channel];
> +	s64 d, t;
> +	int out;
> +
> +	ASSERT(mutex_is_locked(&kvm->arch.vpit->pit_state.lock));
> +
> +	t = ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time));
> +	d = muldiv64(t, PIT_FREQ, 1e9);
>   

NSECS_PER_SEC to avoid people jumping on you saying you can't use 
floating point in the kernel (yes, the compiler converts it at 
compile-time, but they'll still say it).

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.


-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/