[PATCH] zsmalloc: remove zs_compact_control

From: Minchan Kim
Date: Fri Jun 23 2023 - 12:45:33 EST


__zs_compact always putback src_zspage into class list after
migrate_zspage. Thus, we don't need to keep last position of
src_zspage any more. Let's remove it.

Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
---
mm/zsmalloc.c | 37 +++++++++----------------------------
1 file changed, 9 insertions(+), 28 deletions(-)

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 4a84f7877669..84beadc088b8 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -1590,25 +1590,14 @@ static unsigned long find_alloced_obj(struct size_class *class,
return find_tagged_obj(class, page, obj_idx, OBJ_ALLOCATED_TAG);
}

-struct zs_compact_control {
- /* Source spage for migration which could be a subpage of zspage */
- struct page *s_page;
- /* Destination page for migration which should be a first page
- * of zspage. */
- struct page *d_page;
- /* Starting object index within @s_page which used for live object
- * in the subpage. */
- int obj_idx;
-};
-
-static void migrate_zspage(struct zs_pool *pool, struct size_class *class,
- struct zs_compact_control *cc)
+static void migrate_zspage(struct zs_pool *pool, struct zspage *src_zspage,
+ struct zspage *dst_zspage)
{
unsigned long used_obj, free_obj;
unsigned long handle;
- struct page *s_page = cc->s_page;
- struct page *d_page = cc->d_page;
- int obj_idx = cc->obj_idx;
+ int obj_idx = 0;
+ struct page *s_page = get_first_page(src_zspage);
+ struct size_class *class = pool->size_class[src_zspage->class];

while (1) {
handle = find_alloced_obj(class, s_page, &obj_idx);
@@ -1621,24 +1610,20 @@ static void migrate_zspage(struct zs_pool *pool, struct size_class *class,
}

used_obj = handle_to_obj(handle);
- free_obj = obj_malloc(pool, get_zspage(d_page), handle);
+ free_obj = obj_malloc(pool, dst_zspage, handle);
zs_object_copy(class, free_obj, used_obj);
obj_idx++;
record_obj(handle, free_obj);
obj_free(class->size, used_obj);

/* Stop if there is no more space */
- if (zspage_full(class, get_zspage(d_page)))
+ if (zspage_full(class, dst_zspage))
break;

/* Stop if there are no more objects to migrate */
- if (zspage_empty(get_zspage(s_page)))
+ if (zspage_empty(src_zspage))
break;
}
-
- /* Remember last position in this iteration */
- cc->s_page = s_page;
- cc->obj_idx = obj_idx;
}

static struct zspage *isolate_src_zspage(struct size_class *class)
@@ -2013,7 +1998,6 @@ static unsigned long zs_can_compact(struct size_class *class)
static unsigned long __zs_compact(struct zs_pool *pool,
struct size_class *class)
{
- struct zs_compact_control cc;
struct zspage *src_zspage = NULL;
struct zspage *dst_zspage = NULL;
unsigned long pages_freed = 0;
@@ -2031,7 +2015,6 @@ static unsigned long __zs_compact(struct zs_pool *pool,
if (!dst_zspage)
break;
migrate_write_lock(dst_zspage);
- cc.d_page = get_first_page(dst_zspage);
}

src_zspage = isolate_src_zspage(class);
@@ -2040,9 +2023,7 @@ static unsigned long __zs_compact(struct zs_pool *pool,

migrate_write_lock_nested(src_zspage);

- cc.obj_idx = 0;
- cc.s_page = get_first_page(src_zspage);
- migrate_zspage(pool, class, &cc);
+ migrate_zspage(pool, src_zspage, dst_zspage);
fg = putback_zspage(class, src_zspage);
migrate_write_unlock(src_zspage);

--
2.41.0.178.g377b9f9a00-goog