Merge branch 'for-linus' of git://git.open-osd.org/linux-open-osd

[~andy/linux] / init / Kconfig

diff --git a/init/Kconfig b/init/Kconfig
index 68699137b1479044434a7a8f6e063bd2cb1b59d8..1398a14b01919d500c59367ff5cffd61d9f39cad 100644 (file)
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -101,6 +101,66 @@ config LOCALVERSION_AUTO
 
          which is done within the script "scripts/setlocalversion".)
 
+config HAVE_KERNEL_GZIP
+       bool
+
+config HAVE_KERNEL_BZIP2
+       bool
+
+config HAVE_KERNEL_LZMA
+       bool
+
+choice
+       prompt "Kernel compression mode"
+       default KERNEL_GZIP
+       depends on HAVE_KERNEL_GZIP || HAVE_KERNEL_BZIP2 || HAVE_KERNEL_LZMA
+       help
+         The linux kernel is a kind of self-extracting executable.
+         Several compression algorithms are available, which differ
+         in efficiency, compression and decompression speed.
+         Compression speed is only relevant when building a kernel.
+         Decompression speed is relevant at each boot.
+
+         If you have any problems with bzip2 or lzma compressed
+         kernels, mail me (Alain Knaff) <alain@knaff.lu>. (An older
+         version of this functionality (bzip2 only), for 2.4, was
+         supplied by Christian Ludwig)
+
+         High compression options are mostly useful for users, who
+         are low on disk space (embedded systems), but for whom ram
+         size matters less.
+
+         If in doubt, select 'gzip'
+
+config KERNEL_GZIP
+       bool "Gzip"
+       depends on HAVE_KERNEL_GZIP
+       help
+         The old and tried gzip compression. Its compression ratio is
+         the poorest among the 3 choices; however its speed (both
+         compression and decompression) is the fastest.
+
+config KERNEL_BZIP2
+       bool "Bzip2"
+       depends on HAVE_KERNEL_BZIP2
+       help
+         Its compression ratio and speed is intermediate.
+         Decompression speed is slowest among the three.  The kernel
+         size is about 10% smaller with bzip2, in comparison to gzip.
+         Bzip2 uses a large amount of memory. For modern kernels you
+         will need at least 8MB RAM or more for booting.
+
+config KERNEL_LZMA
+       bool "LZMA"
+       depends on HAVE_KERNEL_LZMA
+       help
+         The most recent compression algorithm.
+         Its ratio is best, decompression speed is between the other
+         two. Compression is slowest.  The kernel size is about 33%
+         smaller with LZMA in comparison to gzip.
+
+endchoice
+
 config SWAP
        bool "Support for paging of anonymous memory (swap)"
        depends on MMU && BLOCK
@@ -471,7 +531,7 @@ config CGROUP_DEVICE
 
 config CPUSETS
        bool "Cpuset support"
-       depends on SMP && CGROUPS
+       depends on CGROUPS
        help
          This option will let you create and manage CPUSETs which
          allow dynamically partitioning a system into sets of CPUs and
@@ -537,6 +597,8 @@ config CGROUP_MEM_RES_CTLR_SWAP
          is disabled by boot option, this will be automatically disabled and
          there will be no overhead from this. Even when you set this config=y,
          if boot option "noswapaccount" is set, swap will not be accounted.
+         Now, memory usage of swap_cgroup is 2 bytes per entry. If swap page
+         size is 4096bytes, 512k per 1Gbytes of swap.
 
 endif # CGROUPS