[PATCH] mm/memblock.c: using judgment statement can reduce loop and enhance readability.

[PATCH] mm/memblock.c: using judgment statement can reduce loop and enhance readability.

[huanglllzu]

From: Liangliang Huang <huangll@lemote.com>

Signed-off-by: Liangliang Huang <huangll@lemote.com>
---
 mm/memblock.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/mm/memblock.c b/mm/memblock.c
index 913b2520a9a0..e48dea7144bb 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -655,7 +655,11 @@ static int __init_memblock memblock_add_range(struct memblock_type *type,
 			}
 		}
 		/* area below @rend is dealt with, forget about it */
-		base = min(rend, end);
+		if (end < rend) {
+			base = end;
+			break;
+		} else
+			base = rend;
 	}
 
 	/* insert the remaining portion */
-- 
2.25.1

Re: [PATCH] mm/memblock.c: using judgment statement can reduce loop and enhance readability.

[Mike Rapoport]

Hi,

> Subject: [PATCH] mm/memblock.c: using judgment statement can reduce loop and enhance readability.

I disagree.

On Thu, Nov 02, 2023 at 10:37:10AM +0800, huanglllzu@gmail.com wrote:
> From: Liangliang Huang <huangll@lemote.com>
> 
> Signed-off-by: Liangliang Huang <huangll@lemote.com>
> ---
>  mm/memblock.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/mm/memblock.c b/mm/memblock.c
> index 913b2520a9a0..e48dea7144bb 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -655,7 +655,11 @@ static int __init_memblock memblock_add_range(struct memblock_type *type,
>  			}
>  		}
>  		/* area below @rend is dealt with, forget about it */
> -		base = min(rend, end);
> +		if (end < rend) {
> +			base = end;
> +			break;
> +		} else
> +			base = rend;

min() is perfectly clear and there no change in number of iterations of the
loop.

>  	}
>  
>  	/* insert the remaining portion */
> -- 
> 2.25.1
> 

-- 
Sincerely yours,
Mike.

Re: [PATCH] mm/memblock.c: using judgment statement can reduce loop and enhance readability.

[Mike Rapoport]

On Fri, Nov 03, 2023 at 01:30:21PM +0800, 黄亮亮 wrote:
> Hi,this patch can less loop once in this situation:
> base more than rbase and end less than rend.
>                 base           end
>     rbase-----|--------------|-------rend
>       |            |                 |           |
> -------------------------------------------------------->

The loop won't be executed anyway because there's similar condition in the
beginning of the loop. 

Next time when you reply to the kernel mailing lists, please don't top post
and make sure your reply is text-only.

And there is no need to send 4 badly formatted replies.
 
> Mike Rapoport <rppt@kernel.org> 于2023年11月2日周四 16:54写道：
> 
>     Hi,
> 
>     > Subject: [PATCH] mm/memblock.c: using judgment statement can reduce loop
>     and enhance readability.
> 
>     I disagree.
> 
>     On Thu, Nov 02, 2023 at 10:37:10AM +0800, huanglllzu@gmail.com wrote:
>     > From: Liangliang Huang <huangll@lemote.com>
>     >
>     > Signed-off-by: Liangliang Huang <huangll@lemote.com>
>     > ---
>     >  mm/memblock.c | 6 +++++-
>     >  1 file changed, 5 insertions(+), 1 deletion(-)
>     >
>     > diff --git a/mm/memblock.c b/mm/memblock.c
>     > index 913b2520a9a0..e48dea7144bb 100644
>     > --- a/mm/memblock.c
>     > +++ b/mm/memblock.c
>     > @@ -655,7 +655,11 @@ static int __init_memblock memblock_add_range(struct
>     memblock_type *type,
>     >                       }
>     >               }
>     >               /* area below @rend is dealt with, forget about it */
>     > -             base = min(rend, end);
>     > +             if (end < rend) {
>     > +                     base = end;
>     > +                     break;
>     > +             } else
>     > +                     base = rend;
> 
>     min() is perfectly clear and there no change in number of iterations of the
>     loop.
> 
>     >       }
>     > 
>     >       /* insert the remaining portion */
>     > --
>     > 2.25.1
>     >
> 
>     --
>     Sincerely yours,
>     Mike.
> 

-- 
Sincerely yours,
Mike.