mm, THP, swap: unify swap slot free functions to put_swap_page
Now, get_swap_page takes struct page and allocates swap space according
to page size(ie, normal or THP) so it would be more cleaner to introduce
put_swap_page which is a counter function of get_swap_page. Then, it
calls right swap slot free function depending on page's size.
[[email protected]: minor cleanup and fix]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Minchan Kim <[email protected]>
Signed-off-by: "Huang, Ying" <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Cc: Andrea Arcangeli <[email protected]>
Cc: Ebru Akagunduz <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: Kirill A. Shutemov <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Shaohua Li <[email protected]>
Cc: Tejun Heo <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
diff --git a/mm/shmem.c b/mm/shmem.c
index bbb987c..a06f237 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1327,7 +1327,7 @@ static int shmem_writepage(struct page *page, struct writeback_control *wbc)
mutex_unlock(&shmem_swaplist_mutex);
free_swap:
- swapcache_free(swap);
+ put_swap_page(page, swap);
redirty:
set_page_dirty(page);
if (wbc->for_reclaim)
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 16ff89d0..0ad214d 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -231,10 +231,7 @@ int add_to_swap(struct page *page, struct list_head *list)
return 1;
fail_free:
- if (PageTransHuge(page))
- swapcache_free_cluster(entry);
- else
- swapcache_free(entry);
+ put_swap_page(page, entry);
fail:
if (PageTransHuge(page) && !split_huge_page_to_list(page, list))
goto retry;
@@ -259,11 +256,7 @@ void delete_from_swap_cache(struct page *page)
__delete_from_swap_cache(page);
spin_unlock_irq(&address_space->tree_lock);
- if (PageTransHuge(page))
- swapcache_free_cluster(entry);
- else
- swapcache_free(entry);
-
+ put_swap_page(page, entry);
page_ref_sub(page, hpage_nr_pages(page));
}
@@ -415,7 +408,7 @@ struct page *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask,
* add_to_swap_cache() doesn't return -EEXIST, so we can safely
* clear SWAP_HAS_CACHE flag.
*/
- swapcache_free(entry);
+ put_swap_page(new_page, entry);
} while (err != -ENOMEM);
if (new_page)
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 984f0dd9..8a6cdf9 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1148,7 +1148,7 @@ void swap_free(swp_entry_t entry)
/*
* Called after dropping swapcache to decrease refcnt to swap entries.
*/
-void swapcache_free(swp_entry_t entry)
+static void swapcache_free(swp_entry_t entry)
{
struct swap_info_struct *p;
@@ -1160,7 +1160,7 @@ void swapcache_free(swp_entry_t entry)
}
#ifdef CONFIG_THP_SWAP
-void swapcache_free_cluster(swp_entry_t entry)
+static void swapcache_free_cluster(swp_entry_t entry)
{
unsigned long offset = swp_offset(entry);
unsigned long idx = offset / SWAPFILE_CLUSTER;
@@ -1184,8 +1184,20 @@ void swapcache_free_cluster(swp_entry_t entry)
swap_free_cluster(si, idx);
spin_unlock(&si->lock);
}
+#else
+static inline void swapcache_free_cluster(swp_entry_t entry)
+{
+}
#endif /* CONFIG_THP_SWAP */
+void put_swap_page(struct page *page, swp_entry_t entry)
+{
+ if (!PageTransHuge(page))
+ swapcache_free(entry);
+ else
+ swapcache_free_cluster(entry);
+}
+
void swapcache_free_entries(swp_entry_t *entries, int n)
{
struct swap_info_struct *p, *prev;
diff --git a/mm/vmscan.c b/mm/vmscan.c
index a10e058..cb7c154 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -708,7 +708,7 @@ static int __remove_mapping(struct address_space *mapping, struct page *page,
mem_cgroup_swapout(page, swap);
__delete_from_swap_cache(page);
spin_unlock_irqrestore(&mapping->tree_lock, flags);
- swapcache_free(swap);
+ put_swap_page(page, swap);
} else {
void (*freepage)(struct page *);
void *shadow = NULL;
