On Wed, Jul 08, 2015 at 05:19:10PM +0100, Marc Zyngier wrote: > --- /dev/null > +++ b/arch/arm64/kvm/vhe-macros.h > @@ -0,0 +1,36 @@ > +/* > + * Copyright (C) 2015 - ARM Ltd > + * Author: Marc Zyngier <marc.zyngier@xxxxxxx> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License > + * along with this program. If not, see <http://www.gnu.org/licenses/>. > + */ > + > +#ifndef __ARM64_VHE_MACROS_H__ > +#define __ARM64_VHE_MACROS_H__ > + > +#include <asm/alternative.h> > +#include <asm/cpufeature.h> > + > +#ifdef __ASSEMBLY__ > + > +/* Hack to allow stringification of macros... */ > +#define __S__(a,args...) __stringify(a, ##args) > +#define _S_(a,args...) __S__(a, args) > + > +.macro ifnvhe nonvhe vhe > + alternative_insn "\nonvhe", "\vhe", ARM64_HAS_VIRT_HOST_EXTN > +.endm I always found the alternative_insn tricks hard to read but with Daniel's patch queued in -next it gets slightly better. If you are not targeting 4.3, could you do something like (untested): .macro vhe_if_not alternative_if_not ARM64_HAS_VIRT_HOST_EXTN .endm .macro vhe_else alternative_else CONFIG_ARM64_VHE .endm .macro vhe_endif alternative_endif CONFIG_ARM64_VHE .endm The kvm_call_hyp, for example, would become: ENTRY(kvm_call_hyp) vhe_if_not hvc #0 ret vhe_else nop push lr, xzr vhe_endif Or you can even ignore defining new vhe_* macros altogether and just use "alternative_if_not ARM64_HAS_VIRT_HOST_EXTN" directly (more to type) but you may be able to avoid a vhe-macros.h file. -- Catalin -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
