| Message ID | 20230624053120.643409-3-senozhatsky@chromium.org (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | zsmalloc: small compaction improvements | expand |
On Sat, Jun 24, 2023 at 02:12:15PM +0900, Sergey Senozhatsky wrote: > Destination zspage fullness check need to be done after > zs_object_copy() because that's where source and destination > zspages fullness change. Checking destination zspage fullness > before zs_object_copy() may cause migration to loop through > source zspage sub-pages scanning for allocate objects just to > find out at the end that the destination zspage is full. > > Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> Acked-by: Minchan Kim <minchan@kernel.org>
diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c index 5d60eaedc3b7..4a84f7877669 100644 --- a/mm/zsmalloc.c +++ b/mm/zsmalloc.c @@ -1620,10 +1620,6 @@ static void migrate_zspage(struct zs_pool *pool, struct size_class *class, continue; } - /* Stop if there is no more space */ - if (zspage_full(class, get_zspage(d_page))) - break; - used_obj = handle_to_obj(handle); free_obj = obj_malloc(pool, get_zspage(d_page), handle); zs_object_copy(class, free_obj, used_obj); @@ -1631,6 +1627,10 @@ static void migrate_zspage(struct zs_pool *pool, struct size_class *class, record_obj(handle, free_obj); obj_free(class->size, used_obj); + /* Stop if there is no more space */ + if (zspage_full(class, get_zspage(d_page))) + break; + /* Stop if there are no more objects to migrate */ if (zspage_empty(get_zspage(s_page))) break;
Destination zspage fullness check need to be done after zs_object_copy() because that's where source and destination zspages fullness change. Checking destination zspage fullness before zs_object_copy() may cause migration to loop through source zspage sub-pages scanning for allocate objects just to find out at the end that the destination zspage is full. Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org> --- mm/zsmalloc.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)