2023-02-15 23:03:49

by SeongJae Park

Subject: [PATCH v2 0/2] mm/memory_hotplug: cleanup do_migrate_range()

Make do_migrate_range() return value mechanism simple.

Changes from v1
(https://lore.kernel.org/linux-mm/[email protected]/)
- Simply return nothing from do_migrate_range() (David Hildenbrand)
- Add a cleanup for 'ret' variable

SeongJae Park (2):
mm/memory_hotplug: return nothing from do_migrate_range()
mm/memory_hotplug: cleanup 'ret' variable usage in do_migrate_range()

mm/memory_hotplug.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

--
2.25.1

2023-02-15 23:03:56

by SeongJae Park

Subject: [PATCH v2 2/2] mm/memory_hotplug: cleanup 'ret' variable usage in do_migrate_range()

Because do_migrate_range() is returning nothing, some 'ret' variable
usages are unnecessary. Remove unnecessary usage and reduce its scope.

Signed-off-by: SeongJae Park <[email protected]>
---
mm/memory_hotplug.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 6c615ba1a5c7..6df3072d11df 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1624,7 +1624,6 @@ static void do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
{
unsigned long pfn;
struct page *page, *head;
- int ret = 0;
LIST_HEAD(source);
static DEFINE_RATELIMIT_STATE(migrate_rs, DEFAULT_RATELIMIT_INTERVAL,
DEFAULT_RATELIMIT_BURST);
@@ -1678,7 +1677,6 @@ static void do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
page_is_file_lru(page));

} else {
- ret = -EBUSY;
if (__ratelimit(&migrate_rs)) {
pr_warn("failed to isolate pfn %lx\n", pfn);
dump_page(page, "isolation failed");
@@ -1692,6 +1690,7 @@ static void do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
.nmask = &nmask,
.gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
};
+ int ret;

/*
* We have checked that migration range is on a single zone so
--
2.25.1

2023-02-16 09:50:20

by David Hildenbrand

Subject: Re: [PATCH v2 2/2] mm/memory_hotplug: cleanup 'ret' variable usage in do_migrate_range()

On 16.02.23 00:03, SeongJae Park wrote:
> Because do_migrate_range() is returning nothing, some 'ret' variable
> usages are unnecessary. Remove unnecessary usage and reduce its scope.
>
> Signed-off-by: SeongJae Park <[email protected]>
> ---
> mm/memory_hotplug.c | 3 +--
> 1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
> index 6c615ba1a5c7..6df3072d11df 100644
> --- a/mm/memory_hotplug.c
> +++ b/mm/memory_hotplug.c
> @@ -1624,7 +1624,6 @@ static void do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
> {
> unsigned long pfn;
> struct page *page, *head;
> - int ret = 0;
> LIST_HEAD(source);
> static DEFINE_RATELIMIT_STATE(migrate_rs, DEFAULT_RATELIMIT_INTERVAL,
> DEFAULT_RATELIMIT_BURST);
> @@ -1678,7 +1677,6 @@ static void do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
> page_is_file_lru(page));
>
> } else {
> - ret = -EBUSY;
> if (__ratelimit(&migrate_rs)) {
> pr_warn("failed to isolate pfn %lx\n", pfn);
> dump_page(page, "isolation failed");
> @@ -1692,6 +1690,7 @@ static void do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
> .nmask = &nmask,
> .gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
> };
> + int ret;
>
> /*
> * We have checked that migration range is on a single zone so

Please squash that into the previous patch, just calling it
"mm/memory_hotplug: cleanup return value handling in do_migrate_range()"
or similar.

--
Thanks,

David / dhildenb