mm/zpool: implement common zpool api to zbud/zsmalloc
Add zpool api.
zpool provides an interface for memory storage, typically of compressed
memory. Users can select what backend to use; currently the only
implementations are zbud, a low density implementation with up to two
compressed pages per storage page, and zsmalloc, a higher density
implementation with multiple compressed pages per storage page.
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Tested-by: Seth Jennings <sjennings@variantweb.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Weijie Yang <weijie.yang@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/Kconfig b/mm/Kconfig
index f4899ec..12179b8 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -519,15 +519,17 @@
If unsure, leave the default value "7".
-config ZBUD
- tristate
- default n
+config MEM_SOFT_DIRTY
+ bool "Track memory changes"
+ depends on CHECKPOINT_RESTORE && HAVE_ARCH_SOFT_DIRTY && PROC_FS
+ select PROC_PAGE_MONITOR
help
- A special purpose allocator for storing compressed pages.
- It is designed to store up to two compressed pages per physical
- page. While this design limits storage density, it has simple and
- deterministic reclaim properties that make it preferable to a higher
- density approach when reclaim will be used.
+ This option enables memory changes tracking by introducing a
+ soft-dirty bit on pte-s. This bit it set when someone writes
+ into a page just as regular dirty bit, but unlike the latter
+ it can be cleared by hands.
+
+ See Documentation/vm/soft-dirty.txt for more details.
config ZSWAP
bool "Compressed cache for swap pages (EXPERIMENTAL)"
@@ -549,17 +551,22 @@
they have not be fully explored on the large set of potential
configurations and workloads that exist.
-config MEM_SOFT_DIRTY
- bool "Track memory changes"
- depends on CHECKPOINT_RESTORE && HAVE_ARCH_SOFT_DIRTY && PROC_FS
- select PROC_PAGE_MONITOR
+config ZPOOL
+ tristate "Common API for compressed memory storage"
+ default n
help
- This option enables memory changes tracking by introducing a
- soft-dirty bit on pte-s. This bit it set when someone writes
- into a page just as regular dirty bit, but unlike the latter
- it can be cleared by hands.
+ Compressed memory storage API. This allows using either zbud or
+ zsmalloc.
- See Documentation/vm/soft-dirty.txt for more details.
+config ZBUD
+ tristate "Low density storage for compressed pages"
+ default n
+ help
+ A special purpose allocator for storing compressed pages.
+ It is designed to store up to two compressed pages per physical
+ page. While this design limits storage density, it has simple and
+ deterministic reclaim properties that make it preferable to a higher
+ density approach when reclaim will be used.
config ZSMALLOC
tristate "Memory allocator for compressed pages"