From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cedric Le Goater <clg@fr.ibm.com>
Subject: Re: [PATCH v2 3/3] KVM: PPC: Book3S: MMIO emulation support for little
 endian guests
Date: Fri, 08 Nov 2013 15:29:21 +0100
Message-ID: <527CF541.4080508@fr.ibm.com>
References: <1381241531-27940-4-git-send-email-clg@fr.ibm.com> <A60A1153-73A3-4F0C-BA3D-4F2B6E0E1D28@suse.de> <20131008233123.GB17420@iris.ozlabs.ibm.com> <5F0A1154-D417-454C-A3CD-59AEF7EF0D97@suse.de> <20131009055920.GA10650@drongo> <B26163CF-F7B5-4396-A544-DC9FEF983D34@suse.de> <20131010101607.GB9906@iris.ozlabs.ibm.com> <3404F831-6354-4C22-B06C-64628279CC1F@suse.de> <5278E472.5060604@fr.ibm.com> <84018BDE-858B-4F59-8AA0-9135CCFF4720@suse.de> <20131106055537.GH14842@drongo>
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Cc: Alexander Graf <agraf@suse.de>,
	"kvm-ppc@vger.kernel.org" <kvm-ppc@vger.kernel.org>,
	"kvm@vger.kernel.org mailing list" <kvm@vger.kernel.org>
To: Paul Mackerras <paulus@samba.org>
Return-path: <kvm-ppc-owner@vger.kernel.org>
In-Reply-To: <20131106055537.GH14842@drongo>
Sender: kvm-ppc-owner@vger.kernel.org
List-Id: kvm.vger.kernel.org

On 11/06/2013 06:55 AM, Paul Mackerras wrote:
> On Tue, Nov 05, 2013 at 02:01:14PM +0100, Alexander Graf wrote:
>>
>> On 05.11.2013, at 13:28, Cedric Le Goater <clg@fr.ibm.com> wrote:
>>
>>> +/*
>>> + * Compare endian order of host and guest to determine whether we need
>>> + * to byteswap or not
>>> + */
>>> static inline bool kvmppc_need_byteswap(struct kvm_vcpu *vcpu)
>>> {
>>> -       return vcpu->arch.shared->msr & MSR_LE;
>>> +       return ((mfmsr() & (MSR_LE)) >> MSR_LE_LG) ^
>>
>> mfmsr() is slow. Just use #ifdef __LITTLE_ENDIAN__.
> 
> Or (MSR_KERNEL & MSR_LE).

yes. That is better. I will resend the patch with an update. That was 
quite laborious for a single line patch ... 

Thanks,

C.