From 2847e3478c3d8119eedc3e0cb85a308b21f681dd Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Fri, 22 Jul 2005 18:19:20 -0400 Subject: [PATCH] x86: use alternative instructions for fnsave/fxsave too This one ends up using an inline asm format that claims to read memory and then clobber it (rather than just write it directly), which made it easier to use the existing "alternative_input()" infrastructure support. Now the fxsave code matches the fxrstor. --- include/asm-i386/i387.h | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/include/asm-i386/i387.h b/include/asm-i386/i387.h index e678609bb5..6747006743 100644 --- a/include/asm-i386/i387.h +++ b/include/asm-i386/i387.h @@ -33,7 +33,7 @@ extern void init_fpu(struct task_struct *); "nop ; frstor %1", \ "fxrstor %1", \ X86_FEATURE_FXSR, \ - "m" ((tsk)->thread.i387.fsave)) + "m" ((tsk)->thread.i387.fxsave)) extern void kernel_fpu_begin(void); #define kernel_fpu_end() do { stts(); preempt_enable(); } while(0) @@ -43,13 +43,12 @@ extern void kernel_fpu_begin(void); */ static inline void __save_init_fpu( struct task_struct *tsk ) { - if ( cpu_has_fxsr ) { - asm volatile( "fxsave %0 ; fnclex" - : "=m" (tsk->thread.i387.fxsave) ); - } else { - asm volatile( "fnsave %0 ; fwait" - : "=m" (tsk->thread.i387.fsave) ); - } + alternative_input( + "fnsave %1 ; fwait ;" GENERIC_NOP2, + "fxsave %1 ; fnclex", + X86_FEATURE_FXSR, + "m" (tsk->thread.i387.fxsave) + :"memory"); tsk->thread_info->status &= ~TS_USEDFPU; } -- 2.39.5