From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir.fraser@eu.citrix.com>
Subject: Re: [PATCH] apic: clean up msr handling
Date: Fri, 11 Jun 2010 14:49:39 +0100
Message-ID: <C837FD83.1756A%keir.fraser@eu.citrix.com>
References: <4C1259000200007800006290@vpn.id2.novell.com>
Mime-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xensource.com>
In-Reply-To: <4C1259000200007800006290@vpn.id2.novell.com>
List-Unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xensource.com>
List-Help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-Subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
Sender: xen-devel-bounces@lists.xensource.com
Errors-To: xen-devel-bounces@lists.xensource.com
To: Jan Beulich <JBeulich@novell.com>, Christoph Egger <Christoph.Egger@amd.com>
Cc: "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>
List-Id: xen-devel@lists.xenproject.org

On 11/06/2010 14:40, "Jan Beulich" <JBeulich@novell.com> wrote:

>>>> On 11.06.10 at 15:22, Christoph Egger <Christoph.Egger@amd.com> wrote:
>> -static inline void write_efer(u64 val)
>> -{
>> -    this_cpu(efer) = val;
>> -    wrmsrl(MSR_EFER, val);
>> -}
>> +#define write_efer(val) do { \
>> +    this_cpu(efer) = val; \
>> +    wrmsrl(MSR_EFER, val); \
>> +} while(0)
> 
> This isn't a good change imo: You now require all current and future
> users of write_efer() to not pass expressions with side effects.
> 
> Also, is doesn't really look like a cleanup to me, more like a
> complication.

Hm, I didn't spot that one. It's odd since I thought Christoph was changign
macros into inlien functions where possible. Maybe he just changes in
whichever direction makes his patch bigger? ;-)

 -- Keir