This patch promotes the slab-based zsmalloc memory allocator
from the staging tree to mm/
zcache depends on this allocator for storing compressed RAM pages
in an efficient way under system wide memory pressure where
high-order (greater than 0) page allocation are very likely to
fail.
For more information on zsmalloc and its internals, read the
documentation at the top of the zsmalloc c file.
Signed-off-by: Seth Jennings <sjenning@xxxxxxxxxxxxxxxxxx>
---
drivers/staging/Kconfig | 2 --
drivers/staging/Makefile | 1 -
drivers/staging/zcache/zcache-main.c | 4 ++--
drivers/staging/zram/zram_drv.h | 3 +--
drivers/staging/zsmalloc/Kconfig | 10 ----------
drivers/staging/zsmalloc/Makefile | 3 ---
.../staging/zsmalloc => include/linux}/zsmalloc.h | 0
mm/Kconfig | 18 ++++++++++++++++++
mm/Makefile | 1 +
.../zsmalloc/zsmalloc-main.c => mm/zsmalloc.c | 3 +--
10 files changed, 23 insertions(+), 22 deletions(-)
delete mode 100644 drivers/staging/zsmalloc/Kconfig
delete mode 100644 drivers/staging/zsmalloc/Makefile
rename {drivers/staging/zsmalloc => include/linux}/zsmalloc.h (100%)
rename drivers/staging/zsmalloc/zsmalloc-main.c => mm/zsmalloc.c (99%)
diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig
index e3402d5..b7f7bc7 100644
--- a/drivers/staging/Kconfig
+++ b/drivers/staging/Kconfig
@@ -78,8 +78,6 @@ source "drivers/staging/zram/Kconfig"
source "drivers/staging/zcache/Kconfig"
-source "drivers/staging/zsmalloc/Kconfig"
-
source "drivers/staging/wlags49_h2/Kconfig"
source "drivers/staging/wlags49_h25/Kconfig"
diff --git a/drivers/staging/Makefile b/drivers/staging/Makefile
index 3be59d0..ad74bee 100644
--- a/drivers/staging/Makefile
+++ b/drivers/staging/Makefile
@@ -34,7 +34,6 @@ obj-$(CONFIG_DX_SEP) += sep/
obj-$(CONFIG_IIO) += iio/
obj-$(CONFIG_ZRAM) += zram/
obj-$(CONFIG_ZCACHE) += zcache/
-obj-$(CONFIG_ZSMALLOC) += zsmalloc/
obj-$(CONFIG_WLAGS49_H2) += wlags49_h2/
obj-$(CONFIG_WLAGS49_H25) += wlags49_h25/
obj-$(CONFIG_FB_SM7XX) += sm7xxfb/
diff --git a/drivers/staging/zcache/zcache-main.c b/drivers/staging/zcache/zcache-main.c
index c214977..06ce28f 100644
--- a/drivers/staging/zcache/zcache-main.c
+++ b/drivers/staging/zcache/zcache-main.c
@@ -32,9 +32,9 @@
#include <linux/crypto.h>
#include <linux/string.h>
#include <linux/idr.h>
-#include "tmem.h"
+#include <linux/zsmalloc.h>
-#include "../zsmalloc/zsmalloc.h"
+#include "tmem.h"
#ifdef CONFIG_CLEANCACHE
#include <linux/cleancache.h>
diff --git a/drivers/staging/zram/zram_drv.h b/drivers/staging/zram/zram_drv.h
index 572c0b1..f6d0925 100644
--- a/drivers/staging/zram/zram_drv.h
+++ b/drivers/staging/zram/zram_drv.h
@@ -17,8 +17,7 @@
#include <linux/spinlock.h>
#include <linux/mutex.h>
-
-#include "../zsmalloc/zsmalloc.h"
+#include <linux/zsmalloc.h>
/*
* Some arbitrary value. This is just to catch
diff --git a/drivers/staging/zsmalloc/Kconfig b/drivers/staging/zsmalloc/Kconfig
deleted file mode 100644
index 9084565..0000000
--- a/drivers/staging/zsmalloc/Kconfig
+++ /dev/null
@@ -1,10 +0,0 @@
-config ZSMALLOC
- tristate "Memory allocator for compressed pages"
- default n
- help
- zsmalloc is a slab-based memory allocator designed to store
- compressed RAM pages. zsmalloc uses virtual memory mapping
- in order to reduce fragmentation. However, this results in a
- non-standard allocator interface where a handle, not a pointer, is
- returned by an alloc(). This handle must be mapped in order to
- access the allocated space.
diff --git a/drivers/staging/zsmalloc/Makefile b/drivers/staging/zsmalloc/Makefile
deleted file mode 100644
index b134848..0000000
--- a/drivers/staging/zsmalloc/Makefile
+++ /dev/null
@@ -1,3 +0,0 @@
-zsmalloc-y := zsmalloc-main.o
-
-obj-$(CONFIG_ZSMALLOC) += zsmalloc.o
diff --git a/drivers/staging/zsmalloc/zsmalloc.h b/include/linux/zsmalloc.h
similarity index 100%
rename from drivers/staging/zsmalloc/zsmalloc.h
rename to include/linux/zsmalloc.h
diff --git a/mm/Kconfig b/mm/Kconfig
index d5c8019..2586b66 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -411,3 +411,21 @@ config FRONTSWAP
and swap data is stored as normal on the matching swap device.
If unsure, say Y to enable frontswap.
+
+config ZSMALLOC
+ tristate "Memory allocator for compressed pages"
+ default n
+ help
+ zsmalloc is a slab-based memory allocator designed to store
+ compressed RAM pages. zsmalloc uses a memory pool that combines
+ single pages into higher order pages by linking them together
+ using the fields of the struct page. Allocations are then
+ mapped through copy buffers or VM mapping, in order to reduce
+ memory pool fragmentation and increase allocation success rate under
+ memory pressure.
+
+ This results in a non-standard allocator interface where
+ a handle, not a pointer, is returned by the allocation function.
+ This handle must be mapped in order to access the allocated space.
+
+ If unsure, say N.
diff --git a/mm/Makefile b/mm/Makefile
index 92753e2..8a3d7bea 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -57,3 +57,4 @@ obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o
obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o
obj-$(CONFIG_CLEANCACHE) += cleancache.o
obj-$(CONFIG_MEMORY_ISOLATION) += page_isolation.o
+obj-$(CONFIG_ZSMALLOC) += zsmalloc.o
diff --git a/drivers/staging/zsmalloc/zsmalloc-main.c b/mm/zsmalloc.c
similarity index 99%
rename from drivers/staging/zsmalloc/zsmalloc-main.c
rename to mm/zsmalloc.c
index 09a9d35..6b20429 100644
--- a/drivers/staging/zsmalloc/zsmalloc-main.c
+++ b/mm/zsmalloc.c
@@ -78,8 +78,7 @@
#include <linux/hardirq.h>
#include <linux/spinlock.h>
#include <linux/types.h>
-
-#include "zsmalloc.h"
+#include <linux/zsmalloc.h>
/*
* This must be power of 2 and greater than of equal to sizeof(link_free).
--
1.7.9.5
--
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