[PATCH] LoongArch: Slightly clean up drdtime

Xi Ruoyao posted 1 patch 2 years ago
arch/loongarch/include/asm/loongarch.h | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
[PATCH] LoongArch: Slightly clean up drdtime
Posted by Xi Ruoyao 2 years ago
As we are just discarding the stable clock ID, simply write it into
$zero instead of allocating a temporary register.

Signed-off-by: Xi Ruoyao <xry111@xry111.site>
---
 arch/loongarch/include/asm/loongarch.h | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h
index 9b4957cefa8a..46366e783c84 100644
--- a/arch/loongarch/include/asm/loongarch.h
+++ b/arch/loongarch/include/asm/loongarch.h
@@ -1098,12 +1098,11 @@
 
 static __always_inline u64 drdtime(void)
 {
-	int rID = 0;
 	u64 val = 0;
 
 	__asm__ __volatile__(
-		"rdtime.d %0, %1 \n\t"
-		: "=r"(val), "=r"(rID)
+		"rdtime.d %0, $zero\n\t"
+		: "=r"(val)
 		:
 		);
 	return val;
-- 
2.43.0
Ping: [PATCH] LoongArch: Slightly clean up drdtime
Posted by Xi Ruoyao 2 years ago
Ping.

On Sun, 2023-11-26 at 20:17 +0800, Xi Ruoyao wrote:
> As we are just discarding the stable clock ID, simply write it into
> $zero instead of allocating a temporary register.
> 
> Signed-off-by: Xi Ruoyao <xry111@xry111.site>
> ---
>  arch/loongarch/include/asm/loongarch.h | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h
> index 9b4957cefa8a..46366e783c84 100644
> --- a/arch/loongarch/include/asm/loongarch.h
> +++ b/arch/loongarch/include/asm/loongarch.h
> @@ -1098,12 +1098,11 @@
>  
>  static __always_inline u64 drdtime(void)
>  {
> -	int rID = 0;
>  	u64 val = 0;
>  
>  	__asm__ __volatile__(
> -		"rdtime.d %0, %1 \n\t"
> -		: "=r"(val), "=r"(rID)
> +		"rdtime.d %0, $zero\n\t"
> +		: "=r"(val)
>  		:
>  		);
>  	return val;

-- 
Xi Ruoyao <xry111@xry111.site>
School of Aerospace Science and Technology, Xidian University
Re: Ping: [PATCH] LoongArch: Slightly clean up drdtime
Posted by Huacai Chen 2 years ago
Queued, thanks.

Huacai

On Tue, Dec 5, 2023 at 4:01 PM Xi Ruoyao <xry111@xry111.site> wrote:
>
> Ping.
>
> On Sun, 2023-11-26 at 20:17 +0800, Xi Ruoyao wrote:
> > As we are just discarding the stable clock ID, simply write it into
> > $zero instead of allocating a temporary register.
> >
> > Signed-off-by: Xi Ruoyao <xry111@xry111.site>
> > ---
> >  arch/loongarch/include/asm/loongarch.h | 5 ++---
> >  1 file changed, 2 insertions(+), 3 deletions(-)
> >
> > diff --git a/arch/loongarch/include/asm/loongarch.h b/arch/loongarch/include/asm/loongarch.h
> > index 9b4957cefa8a..46366e783c84 100644
> > --- a/arch/loongarch/include/asm/loongarch.h
> > +++ b/arch/loongarch/include/asm/loongarch.h
> > @@ -1098,12 +1098,11 @@
> >
> >  static __always_inline u64 drdtime(void)
> >  {
> > -     int rID = 0;
> >       u64 val = 0;
> >
> >       __asm__ __volatile__(
> > -             "rdtime.d %0, %1 \n\t"
> > -             : "=r"(val), "=r"(rID)
> > +             "rdtime.d %0, $zero\n\t"
> > +             : "=r"(val)
> >               :
> >               );
> >       return val;
>
> --
> Xi Ruoyao <xry111@xry111.site>
> School of Aerospace Science and Technology, Xidian University