[PATCH v2 02/18] zsmalloc: use first_page rather than page

Minchan Kim
2016-03-21T06:30:36Z

This patch cleans up function parameter "struct page".
Many functions of zsmalloc expects that page paramter is "first_page"
so use "first_page" rather than "page" for code readability.

Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
---
mm/zsmalloc.c | 62 ++++++++++++++++++++++++++++++-----------------------------
1 file changed, 32 insertions(+), 30 deletions(-)

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index e72efb109fde..b09a80d398c9 100644
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -413,26 +413,28 @@ static int is_last_page(struct page *page)
return PagePrivate2(page);
}

-static void get_zspage_mapping(struct page *page, unsigned int *class_idx,
+static void get_zspage_mapping(struct page *first_page,
+ unsigned int *class_idx,
enum fullness_group *fullness)
{
unsigned long m;
- BUG_ON(!is_first_page(page));
+ BUG_ON(!is_first_page(first_page));

- m = (unsigned long)page->mapping;
+ m = (unsigned long)first_page->mapping;
*fullness = m & FULLNESS_MASK;
*class_idx = (m >> FULLNESS_BITS) & CLASS_IDX_MASK;
}

-static void set_zspage_mapping(struct page *page, unsigned int class_idx,
+static void set_zspage_mapping(struct page *first_page,
+ unsigned int class_idx,
enum fullness_group fullness)
{
unsigned long m;
- BUG_ON(!is_first_page(page));
+ BUG_ON(!is_first_page(first_page));

m = ((class_idx & CLASS_IDX_MASK) << FULLNESS_BITS) |
(fullness & FULLNESS_MASK);
- page->mapping = (struct address_space *)m;
+ first_page->mapping = (struct address_space *)m;
}

/*
@@ -625,14 +627,14 @@ static inline void zs_pool_stat_destroy(struct zs_pool *pool)
* the pool (not yet implemented). This function returns fullness
* status of the given page.
*/
-static enum fullness_group get_fullness_group(struct page *page)
+static enum fullness_group get_fullness_group(struct page *first_page)
{
int inuse, max_objects;
enum fullness_group fg;
- BUG_ON(!is_first_page(page));
+ BUG_ON(!is_first_page(first_page));

- inuse = page->inuse;
- max_objects = page->objects;
+ inuse = first_page->inuse;
+ max_objects = first_page->objects;

if (inuse == 0)
fg = ZS_EMPTY;
@@ -652,12 +654,12 @@ static enum fullness_group get_fullness_group(struct page *page)
* have. This functions inserts the given zspage into the freelist
* identified by <class, fullness_group>.
*/
-static void insert_zspage(struct page *page, struct size_class *class,
+static void insert_zspage(struct page *first_page, struct size_class *class,
enum fullness_group fullness)
{
struct page **head;

- BUG_ON(!is_first_page(page));
+ BUG_ON(!is_first_page(first_page));

if (fullness >= _ZS_NR_FULLNESS_GROUPS)
return;
@@ -667,7 +669,7 @@ static void insert_zspage(struct page *page, struct size_class *class,

head = &class->fullness_list[fullness];
if (!*head) {
- *head = page;
+ *head = first_page;
return;
}

@@ -675,21 +677,21 @@ static void insert_zspage(struct page *page, struct size_class *class,
* We want to see more ZS_FULL pages and less almost
* empty/full. Put pages with higher ->inuse first.
*/
- list_add_tail(&page->lru, &(*head)->lru);
- if (page->inuse >= (*head)->inuse)
- *head = page;
+ list_add_tail(&first_page->lru, &(*head)->lru);
+ if (first_page->inuse >= (*head)->inuse)
+ *head = first_page;
}

/*
* This function removes the given zspage from the freelist identified
* by <class, fullness_group>.
*/
-static void remove_zspage(struct page *page, struct size_class *class,
+static void remove_zspage(struct page *first_page, struct size_class *class,
enum fullness_group fullness)
{
struct page **head;

- BUG_ON(!is_first_page(page));
+ BUG_ON(!is_first_page(first_page));

if (fullness >= _ZS_NR_FULLNESS_GROUPS)
return;
@@ -698,11 +700,11 @@ static void remove_zspage(struct page *page, struct size_class *class,
BUG_ON(!*head);
if (list_empty(&(*head)->lru))
*head = NULL;
- else if (*head == page)
+ else if (*head == first_page)
*head = (struct page *)list_entry((*head)->lru.next,
struct page, lru);

- list_del_init(&page->lru);
+ list_del_init(&first_page->lru);
zs_stat_dec(class, fullness == ZS_ALMOST_EMPTY ?
CLASS_ALMOST_EMPTY : CLASS_ALMOST_FULL, 1);
}
@@ -717,21 +719,21 @@ static void remove_zspage(struct page *page, struct size_class *class,
* fullness group.
*/
static enum fullness_group fix_fullness_group(struct size_class *class,
- struct page *page)
+ struct page *first_page)
{
int class_idx;
enum fullness_group currfg, newfg;

- BUG_ON(!is_first_page(page));
+ BUG_ON(!is_first_page(first_page));

- get_zspage_mapping(page, &class_idx, &currfg);
- newfg = get_fullness_group(page);
+ get_zspage_mapping(first_page, &class_idx, &currfg);
+ newfg = get_fullness_group(first_page);
if (newfg == currfg)
goto out;

- remove_zspage(page, class, currfg);
- insert_zspage(page, class, newfg);
- set_zspage_mapping(page, class_idx, newfg);
+ remove_zspage(first_page, class, currfg);
+ insert_zspage(first_page, class, newfg);
+ set_zspage_mapping(first_page, class_idx, newfg);

out:
return newfg;
@@ -1234,11 +1236,11 @@ static bool can_merge(struct size_class *prev, int size, int pages_per_zspage)
return true;
}

-static bool zspage_full(struct page *page)
+static bool zspage_full(struct page *first_page)
{
- BUG_ON(!is_first_page(page));
+ BUG_ON(!is_first_page(first_page));

- return page->inuse == page->objects;
+ return first_page->inuse == first_page->objects;
}

unsigned long zs_get_total_pages(struct zs_pool *pool)
--
1.9.1