[RFC PATCH v2 09/21] mm/zsmalloc: convert create_page_chain() and its user to use zsdesc
From: Hyeonggon Yoo
Date: Thu Jul 13 2023 - 00:22:13 EST
Introduce a few helper functions for conversion.
Convert create_page_chain() and its user replace_sub_page() to use zsdesc.
Signed-off-by: Hyeonggon Yoo <42.hyeyoo@xxxxxxxxx>
---
mm/zsmalloc.c | 120 ++++++++++++++++++++++++++++++++++----------------
1 file changed, 81 insertions(+), 39 deletions(-)
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index 06227da86afc..48bfdbbe3b1e 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -346,6 +346,48 @@ static inline void *zsdesc_kmap_atomic(struct zsdesc *zsdesc)
return kmap_atomic(zsdesc_page(zsdesc));
}
+static inline void zsdesc_set_zspage(struct zsdesc *zsdesc,
+ struct zspage *zspage)
+{
+ zsdesc->zspage = zspage;
+}
+
+static inline void zsdesc_set_first(struct zsdesc *zsdesc)
+{
+ SetPagePrivate(zsdesc_page(zsdesc));
+}
+
+static const struct movable_operations zsmalloc_mops;
+
+static inline void zsdesc_set_movable(struct zsdesc *zsdesc)
+{
+ __SetPageMovable(zsdesc_page(zsdesc), &zsmalloc_mops);
+}
+
+static inline void zsdesc_inc_zone_page_state(struct zsdesc *zsdesc)
+{
+ inc_zone_page_state(zsdesc_page(zsdesc), NR_ZSPAGES);
+}
+
+static inline void zsdesc_dec_zone_page_state(struct zsdesc *zsdesc)
+{
+ dec_zone_page_state(zsdesc_page(zsdesc), NR_ZSPAGES);
+}
+
+static inline struct zsdesc *alloc_zsdesc(gfp_t gfp)
+{
+ struct page *page = alloc_page(gfp);
+
+ return page_zsdesc(page);
+}
+
+static inline void free_zsdesc(struct zsdesc *zsdesc)
+{
+ struct page *page = zsdesc_page(zsdesc);
+
+ __free_page(page);
+}
+
/* huge object: pages_per_zspage == 1 && maxobj_per_zspage == 1 */
static void SetZsHugePage(struct zspage *zspage)
{
@@ -1047,35 +1089,35 @@ static void init_zspage(struct size_class *class, struct zspage *zspage)
}
static void create_page_chain(struct size_class *class, struct zspage *zspage,
- struct page *pages[])
+ struct zsdesc *zsdescs[])
{
int i;
- struct page *page;
- struct page *prev_page = NULL;
- int nr_pages = class->pages_per_zspage;
+ struct zsdesc *zsdesc;
+ struct zsdesc *prev_zsdesc = NULL;
+ int nr_zsdescs = class->pages_per_zspage;
/*
* Allocate individual pages and link them together as:
- * 1. all pages are linked together using page->index
- * 2. each sub-page point to zspage using page->private
+ * 1. all pages are linked together using zsdesc->next
+ * 2. each sub-page point to zspage using zsdesc->zspage
*
- * we set PG_private to identify the first page (i.e. no other sub-page
+ * we set PG_private to identify the first zsdesc (i.e. no other zsdesc
* has this flag set).
*/
- for (i = 0; i < nr_pages; i++) {
- page = pages[i];
- set_page_private(page, (unsigned long)zspage);
- page->index = 0;
+ for (i = 0; i < nr_zsdescs; i++) {
+ zsdesc = zsdescs[i];
+ zsdesc_set_zspage(zsdesc, zspage);
+ zsdesc->next = NULL;
if (i == 0) {
- zspage->first_zsdesc = page_zsdesc(page);
- SetPagePrivate(page);
+ zspage->first_zsdesc = zsdesc;
+ zsdesc_set_first(zsdesc);
if (unlikely(class->objs_per_zspage == 1 &&
class->pages_per_zspage == 1))
SetZsHugePage(zspage);
} else {
- prev_page->index = (unsigned long)page;
+ prev_zsdesc->next = zsdesc;
}
- prev_page = page;
+ prev_zsdesc = zsdesc;
}
}
@@ -1087,7 +1129,7 @@ static struct zspage *alloc_zspage(struct zs_pool *pool,
gfp_t gfp)
{
int i;
- struct page *pages[ZS_MAX_PAGES_PER_ZSPAGE];
+ struct zsdesc *zsdescs[ZS_MAX_PAGES_PER_ZSPAGE];
struct zspage *zspage = cache_alloc_zspage(pool, gfp);
if (!zspage)
@@ -1097,23 +1139,23 @@ static struct zspage *alloc_zspage(struct zs_pool *pool,
migrate_lock_init(zspage);
for (i = 0; i < class->pages_per_zspage; i++) {
- struct page *page;
+ struct zsdesc *zsdesc;
- page = alloc_page(gfp);
- if (!page) {
+ zsdesc = alloc_zsdesc(gfp);
+ if (!zsdesc) {
while (--i >= 0) {
- dec_zone_page_state(pages[i], NR_ZSPAGES);
- __free_page(pages[i]);
+ zsdesc_dec_zone_page_state(zsdescs[i]);
+ free_zsdesc(zsdescs[i]);
}
cache_free_zspage(pool, zspage);
return NULL;
}
- inc_zone_page_state(page, NR_ZSPAGES);
- pages[i] = page;
+ zsdesc_inc_zone_page_state(zsdesc);
+ zsdescs[i] = zsdesc;
}
- create_page_chain(class, zspage, pages);
+ create_page_chain(class, zspage, zsdescs);
init_zspage(class, zspage);
zspage->pool = pool;
@@ -1856,29 +1898,29 @@ static void dec_zspage_isolation(struct zspage *zspage)
zspage->isolated--;
}
-static const struct movable_operations zsmalloc_mops;
-
static void replace_sub_page(struct size_class *class, struct zspage *zspage,
- struct page *newpage, struct page *oldpage)
+ struct zsdesc *new_zsdesc, struct zsdesc *old_zsdesc)
{
- struct page *page;
- struct page *pages[ZS_MAX_PAGES_PER_ZSPAGE] = {NULL, };
+ struct zsdesc *zsdesc;
+ struct zsdesc *zsdescs[ZS_MAX_PAGES_PER_ZSPAGE] = {NULL, };
+ unsigned int first_obj_offset;
int idx = 0;
- page = get_first_page(zspage);
+ zsdesc = get_first_zsdesc(zspage);
do {
- if (page == oldpage)
- pages[idx] = newpage;
+ if (zsdesc == old_zsdesc)
+ zsdescs[idx] = new_zsdesc;
else
- pages[idx] = page;
+ zsdescs[idx] = zsdesc;
idx++;
- } while ((page = get_next_page(page)) != NULL);
+ } while ((zsdesc = get_next_zsdesc(zsdesc)) != NULL);
- create_page_chain(class, zspage, pages);
- set_first_obj_offset(newpage, get_first_obj_offset(oldpage));
+ create_page_chain(class, zspage, zsdescs);
+ first_obj_offset = get_first_obj_offset(zsdesc_page(old_zsdesc));
+ set_first_obj_offset(zsdesc_page(new_zsdesc), first_obj_offset);
if (unlikely(ZsHugePage(zspage)))
- newpage->index = oldpage->index;
- __SetPageMovable(newpage, &zsmalloc_mops);
+ new_zsdesc->handle = old_zsdesc->handle;
+ zsdesc_set_movable(new_zsdesc);
}
static bool zs_page_isolate(struct page *page, isolate_mode_t mode)
@@ -1959,7 +2001,7 @@ static int zs_page_migrate(struct page *newpage, struct page *page,
}
kunmap_atomic(s_addr);
- replace_sub_page(class, zspage, newpage, page);
+ replace_sub_page(class, zspage, page_zsdesc(newpage), page_zsdesc(page));
/*
* Since we complete the data copy and set up new zspage structure,
* it's okay to release the pool's lock.
--
2.41.0