2020-05-24 14:21:04

by DaeRo Lee

Subject: [PATCH] mm/memblock:Do not retry a range that has already been checked

The range that has already been checked
don't have to be checked in a second attempt.

Signed-off-by: daeroro <[email protected]>
---
mm/memblock.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/memblock.c b/mm/memblock.c
index 39aceafc57f6..6f72fae415ee 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1489,7 +1489,7 @@ static void * __init memblock_alloc_internal(

/* retry allocation without lower limit */
if (!alloc && min_addr)
- alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid,
+ alloc = memblock_alloc_range_nid(size, align, 0, min_addr, nid,
exact_nid);

if (!alloc)
--
2.17.1

2020-05-24 17:51:48

by Mike Rapoport

Subject: Re: [PATCH] mm/memblock:Do not retry a range that has already been checked

On Sun, May 24, 2020 at 11:16:40PM +0900, daeroro wrote:
> The range that has already been checked
> don't have to be checked in a second attempt.

The first attempts tries to find free memory in the interval [min_addr,
max_addr) and the second attempt does not care about min_addr and looks
for free memory in the interval [0, max_addr).

Is there a problem you see with this algorthim?

> Signed-off-by: daeroro <[email protected]>
> ---
> mm/memblock.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/mm/memblock.c b/mm/memblock.c
> index 39aceafc57f6..6f72fae415ee 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1489,7 +1489,7 @@ static void * __init memblock_alloc_internal(
>
> /* retry allocation without lower limit */
> if (!alloc && min_addr)
> - alloc = memblock_alloc_range_nid(size, align, 0, max_addr, nid,
> + alloc = memblock_alloc_range_nid(size, align, 0, min_addr, nid,
> exact_nid);
>
> if (!alloc)
> --
> 2.17.1
>

--
Sincerely yours,
Mike.