Commit 0fdaa13e authored Oct 03, 2025 by SeongJae Park Committed by Andrew Morton Nov 16, 2025

Docs/admin-guide/mm/zswap: s/red-black tree/xarray/

The change from commit 796c2c23 ("zswap: replace RB tree with xarray")
is not reflected on the document.  Update the document.

Link: https://lkml.kernel.org/r/20251003203851.43128-5-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>

parent 1f52f3de

Documentation/admin-guide/mm/zswap.rst

+5 −5

Original line number	Diff line number	Diff line
		@@ -59,11 +59,11 @@ returned by the allocation routine and that handle must be mapped before being
		accessed. The compressed memory pool grows on demand and shrinks as compressed
		pages are freed. The pool is not preallocated.

		When a swap page is passed from swapout to zswap, zswap maintains a mapping
		of the swap entry, a combination of the swap type and swap offset, to the
		zsmalloc handle that references that compressed swap page. This mapping is
		achieved with a red-black tree per swap type. The swap offset is the search
		key for the tree nodes.
		When a swap page is passed from swapout to zswap, zswap maintains a mapping of
		the swap entry, a combination of the swap type and swap offset, to the zsmalloc
		handle that references that compressed swap page. This mapping is achieved
		with an xarray per swap type. The swap offset is the search key for the xarray
		nodes.

		During a page fault on a PTE that is a swap entry, the swapin code calls the
		zswap load function to decompress the page into the page allocated by the page