Re: [PATCH 23/23] x86/fpu: Defer FPU state load until return to userspace

[Sebastian Andrzej Siewior]

On 2018-11-07 20:48:58 [+0100], To linux-kernel@xxxxxxxxxxxxxxx wrote:
> index 8c03b42416656..d10b60d80d35a 100644
> --- a/arch/x86/include/asm/fpu/api.h
> +++ b/arch/x86/include/asm/fpu/api.h

The bot complained about missing definition for local_bh_disable() so I
swapped the preempt.h for bottom_half.h at the beginning of this file.

> @@ -27,17 +27,31 @@ extern void __kernel_fpu_end(void);
>  extern void kernel_fpu_begin(void);
>  extern void kernel_fpu_end(void);
>  extern bool irq_fpu_usable(void);
> +extern void fpregs_mark_activate(void);
>  
>  static inline void __fpregs_changes_begin(void)
>  {
>  	preempt_disable();
> +	local_bh_disable();
>  }
>  
>  static inline void __fpregs_changes_end(void)
>  {
> +	local_bh_enable();
>  	preempt_enable();
>  }

Sebastian