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.
[ying.huang@intel.com: minor cleanup and fix]
Link: http://lkml.kernel.org/r/20170515112522.32457-3-ying.huang@intel.com
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Ebru Akagunduz <ebru.akagunduz@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Shaohua Li <shli@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 984f0dd..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;