mm/zswap: s/red-black tree/xarray/

Changes made by commit 796c2c23e1 ("zswap: replace RB tree with xarray")
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Link: https://lkml.kernel.org/r/20251003203851.43128-4-sj@kernel.org
Signed-off-by: SeongJae Park <sj@kernel.org>
Acked-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Acked-by: Nhat Pham <nphamcs@gmail.com>
Reviewed-by: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Chris Li <chrisl@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/zswap.c

@@ -175,7 +175,7 @@ static struct shrinker *zswap_shrinker;
  * This structure contains the metadata for tracking a single compressed
  * page within zswap.
  *
- * swpentry - associated swap entry, the offset indexes into the red-black tree
+ * swpentry - associated swap entry, the offset indexes into the xarray
  * length - the length in bytes of the compressed page data.  Needed during
  *          decompression.
  * referenced - true if the entry recently entered the zswap pool. Unset by the