Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

[karo-tx-linux.git] / mm / Kconfig

diff --git a/mm/Kconfig b/mm/Kconfig
index b2176374b98e5e678ec93acda28cc0891d1c3717..d5c8019c662793886224b872cc494e1ae3d00842 100644 (file)
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -140,9 +140,13 @@ config ARCH_DISCARD_MEMBLOCK
 config NO_BOOTMEM
        boolean
 
+config MEMORY_ISOLATION
+       boolean
+
 # eventually, we can have this option just 'select SPARSEMEM'
 config MEMORY_HOTPLUG
        bool "Allow for memory hot-add"
+       select MEMORY_ISOLATION
        depends on SPARSEMEM || X86_64_ACPI_NUMA
        depends on HOTPLUG && ARCH_ENABLE_MEMORY_HOTPLUG
        depends on (IA64 || X86 || PPC_BOOK3S_64 || SUPERH || S390)
@@ -272,6 +276,7 @@ config MEMORY_FAILURE
        depends on MMU
        depends on ARCH_SUPPORTS_MEMORY_FAILURE
        bool "Enable recovery from hardware memory errors"
+       select MEMORY_ISOLATION
        help
          Enables code to recover from some memory failures on systems
          with MCA recovery. This allows a system to continue running
@@ -389,3 +394,20 @@ config CLEANCACHE
          in a negligible performance hit.
 
          If unsure, say Y to enable cleancache
+
+config FRONTSWAP
+       bool "Enable frontswap to cache swap pages if tmem is present"
+       depends on SWAP
+       default n
+       help
+         Frontswap is so named because it can be thought of as the opposite
+         of a "backing" store for a swap device.  The data is stored into
+         "transcendent memory", memory that is not directly accessible or
+         addressable by the kernel and is of unknown and possibly
+         time-varying size.  When space in transcendent memory is available,
+         a significant swap I/O reduction may be achieved.  When none is
+         available, all frontswap calls are reduced to a single pointer-
+         compare-against-NULL resulting in a negligible performance hit
+         and swap data is stored as normal on the matching swap device.
+
+         If unsure, say Y to enable frontswap.