Re: [Xenomai] [PATCHv2 4/4] cobalt/x86: add ipipe-4.14 eager fpu support

[Henning Schild]

All three kernels are tested now. I addressed comments from the first
review. Unfortunately i did not find a nice split to reduce the ifdef
hell we are in here.

I guess once we drop lazy fpu, most of it will go away.

Henning

Am Fri, 14 Sep 2018 17:10:18 +0200
schrieb Henning Schild <henning.sch...@siemens.com>:

> 4.14 is always eager, unfortunately we will need a few ifdefs inside
> the eager fpu support as well.
> 
> Signed-off-by: Henning Schild <henning.sch...@siemens.com>
> ---
>  .../arch/x86/include/asm/xenomai/wrappers.h   |  4 ++++
>  kernel/cobalt/arch/x86/thread.c               | 21
> ++++++++++++++++++- 2 files changed, 24 insertions(+), 1 deletion(-)
> 
> diff --git a/kernel/cobalt/arch/x86/include/asm/xenomai/wrappers.h
> b/kernel/cobalt/arch/x86/include/asm/xenomai/wrappers.h index
> a47730106..a4cc368a5 100644 ---
> a/kernel/cobalt/arch/x86/include/asm/xenomai/wrappers.h +++
> b/kernel/cobalt/arch/x86/include/asm/xenomai/wrappers.h @@ -32,6
> +32,10 @@ LINUX_VERSION_CODE < KERNEL_VERSION(4,5,0)
>  #define IPIPE_X86_FPU_EAGER
>  #endif
> +#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,14,0)
> +#define IPIPE_X86_FPU_EAGER
> +#endif
> +
>  
>  #if LINUX_VERSION_CODE < KERNEL_VERSION(4,2,0)
>  #include <asm/i387.h>
> diff --git a/kernel/cobalt/arch/x86/thread.c
> b/kernel/cobalt/arch/x86/thread.c index 18cf636e5..2668ce274 100644
> --- a/kernel/cobalt/arch/x86/thread.c
> +++ b/kernel/cobalt/arch/x86/thread.c
> @@ -42,6 +42,7 @@ static struct kmem_cache *xstate_cache;
>  #define cpu_has_xsave boot_cpu_has(X86_FEATURE_XSAVE)
>  #endif
>  
> +#ifndef IPIPE_X86_FPU_EAGER
>  #if LINUX_VERSION_CODE < KERNEL_VERSION(4,2,0)
>  #include <asm/i387.h>
>  #include <asm/fpu-internal.h>
> @@ -72,6 +73,9 @@ static inline void x86_fpregs_activate(struct
> task_struct *t) #define x86_xstate_alignment
> __alignof__(union fpregs_state) 
>  #endif
> +#else /* IPIPE_X86_FPU_EAGER */
> +#define x86_xstate_alignment         __alignof__(union
> fpregs_state) +#endif /* ! IPIPE_X86_FPU_EAGER */
>  
>  #if LINUX_VERSION_CODE < KERNEL_VERSION(4,8,0)
>  /*
> @@ -465,9 +469,15 @@ void xnarch_leave_root(struct xnthread *root)
>       // save fpregs from in-kernel use
>       copy_fpregs_to_fpstate(rootcb->kfpu);
>       kernel_fpu_enable();
> +#if LINUX_VERSION_CODE >= KERNEL_VERSION(4,14,0)
> +     // restore current's fpregs
> +     __cpu_invalidate_fpregs_state();
> +     switch_fpu_finish(&current->thread.fpu, smp_processor_id());
> +#else
>       // mark current thread as not owning the FPU anymore
>       if (&current->thread.fpu.fpstate_active)
>               fpregs_deactivate(&current->thread.fpu);
> +#endif
>  }
>  
>  void xnarch_switch_fpu(struct xnthread *from, struct xnthread *to)
> @@ -528,7 +538,11 @@ void xnarch_init_shadow_tcb(struct xnthread
> *thread) #else /* IPIPE_X86_FPU_EAGER */
>       /* XNFPU is always set */
>       xnthread_set_state(thread, XNFPU);
> +#if LINUX_VERSION_CODE < KERNEL_VERSION(4,14,0)
>       fpu__activate_fpstate_read(&p->thread.fpu);
> +#else
> +     fpu__initialize(&p->thread.fpu);
> +#endif
>  #endif /* ! IPIPE_X86_FPU_EAGER */
>  }
>  
> @@ -537,7 +551,12 @@ int mach_x86_thread_init(void)
>       xstate_cache = kmem_cache_create("cobalt_x86_xstate",
>                                        fpu_kernel_xstate_size,
>                                        x86_xstate_alignment,
> -                                      SLAB_NOTRACK, NULL);
> +#if LINUX_VERSION_CODE < KERNEL_VERSION(4,14,0)
> +                                      SLAB_NOTRACK,
> +#else
> +                                      0,
> +#endif
> +                                      NULL);
>       if (xstate_cache == NULL)
>               return -ENOMEM;
>  



-- 
Siemens AG
Corporate Technology
CT RDA IOT SES-DE
Otto-Hahn-Ring 6
81739 Muenchen, Germany
Mobile: +49 172 8378927
mailto: henning.sch...@siemens.com

_______________________________________________
Xenomai mailing list
Xenomai@xenomai.org
https://xenomai.org/mailman/listinfo/xenomai