[PATCH v2 4/8] mm: swap: use swap_entries_free() drop last ref count in swap_entries_put_nr()

From: Kemeng Shi
Date: Tue Mar 18 2025 - 02:10:43 EST


Use swap_entries_free() to directly free swap entries when the swap
entries are not cached and referenced, without needing to set swap
entries to set intermediate SWAP_HAS_CACHE state.

Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>
Reviewed-by: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx>
---
mm/swapfile.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/mm/swapfile.c b/mm/swapfile.c
index 40e41e514813..2a08d9e89f90 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1490,10 +1490,11 @@ static bool swap_entries_put_nr(struct swap_info_struct *si,
unlock_cluster(ci);
goto fallback;
}
- for (i = 0; i < nr; i++)
- WRITE_ONCE(si->swap_map[offset + i], SWAP_HAS_CACHE);
if (!has_cache)
swap_entries_free(si, ci, entry, nr);
+ else
+ for (i = 0; i < nr; i++)
+ WRITE_ONCE(si->swap_map[offset + i], SWAP_HAS_CACHE);
unlock_cluster(ci);

return has_cache;
--
2.30.0