[PATCH 4/4] mm: don't set page count in deferred_init_pages

Yajun Deng
2023-09-22T07:10:37Z

The operations of page count in deferred_init_pages and deferred_free_range
is the opposite operation. It's unnecessary and time-consuming.

Don't set page count in deferred_init_pages, as it'll be reset later.

The following data was tested on an x86 machine with 190GB of RAM.

before:
node 0 deferred pages initialised in 78ms

after:
node 0 deferred pages initialised in 72ms

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
---
mm/mm_init.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/mm_init.c b/mm/mm_init.c
index 1cc310f706a9..fe78f6916c66 100644
--- a/mm/mm_init.c
+++ b/mm/mm_init.c
@@ -1984,7 +1984,7 @@ static void __init deferred_free_range(unsigned long pfn,
if (nr_pages == MAX_ORDER_NR_PAGES && IS_MAX_ORDER_ALIGNED(pfn)) {
for (i = 0; i < nr_pages; i += pageblock_nr_pages)
set_pageblock_migratetype(page + i, MIGRATE_MOVABLE);
- __free_pages_core(page, MAX_ORDER, MEMINIT_LATE);
+ __free_pages_core(page, MAX_ORDER, MEMINIT_EARLY);
return;
}

@@ -1994,7 +1994,7 @@ static void __init deferred_free_range(unsigned long pfn,
for (i = 0; i < nr_pages; i++, page++, pfn++) {
if (pageblock_aligned(pfn))
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
- __free_pages_core(page, 0, MEMINIT_LATE);
+ __free_pages_core(page, 0, MEMINIT_EARLY);
}
}

@@ -2068,7 +2068,7 @@ static unsigned long __init deferred_init_pages(struct zone *zone,
} else {
page++;
}
- __init_single_page(page, pfn, zid, nid, true, false);
+ __init_single_page(page, pfn, zid, nid, false, false);
nr_pages++;
}
return (nr_pages);
--
2.25.1