X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=init%2FKconfig;h=3ae8ffe738eb4878d9d1fe383e36279026d396e0;hb=33081adf8b89d5a716d7e1c60171768d39795b39;hp=be85a0ab1b822176b4c715266adfea779035af70;hpb=db08bf0877f3464fb0c2c37dcdd9f9683192ea26;p=~andy%2Flinux diff --git a/init/Kconfig b/init/Kconfig index be85a0ab1b8..3ae8ffe738e 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -186,7 +186,7 @@ config KERNEL_LZO depends on HAVE_KERNEL_LZO help Its compression ratio is the poorest among the 4. The kernel - size is about about 10% bigger than gzip; however its speed + size is about 10% bigger than gzip; however its speed (both compression and decompression) is the fastest. endchoice @@ -661,11 +661,14 @@ config BLK_CGROUP Currently, CFQ IO scheduler uses it to recognize task groups and control disk bandwidth allocation (proportional time slice allocation) - to such task groups. + to such task groups. It is also used by bio throttling logic in + block layer to implement upper limit in IO rates on a device. This option only enables generic Block IO controller infrastructure. - One needs to also enable actual IO controlling logic in CFQ for it - to take effect. (CONFIG_CFQ_GROUP_IOSCHED=y). + One needs to also enable actual IO controlling logic/policy. For + enabling proportional weight division of disk bandwidth in CFQ seti + CONFIG_CFQ_GROUP_IOSCHED=y and for enabling throttling policy set + CONFIG_BLK_THROTTLE=y. See Documentation/cgroups/blkio-controller.txt for more information. @@ -683,40 +686,42 @@ config MM_OWNER bool config SYSFS_DEPRECATED - bool - -config SYSFS_DEPRECATED_V2 bool "enable deprecated sysfs features to support old userspace tools" depends on SYSFS default n - select SYSFS_DEPRECATED - help - This option switches the layout of sysfs to the deprecated - version. Do not use it on recent distributions. - - The current sysfs layout features a unified device tree at - /sys/devices/, which is able to express a hierarchy between - class devices. If the deprecated option is set to Y, the - unified device tree is split into a bus device tree at - /sys/devices/ and several individual class device trees at - /sys/class/. The class and bus devices will be connected by - ":" and the "device" links. The "block" - class devices, will not show up in /sys/class/block/. Some - subsystems will suppress the creation of some devices which - depend on the unified device tree. - - This option is not a pure compatibility option that can - be safely enabled on newer distributions. It will change the - layout of sysfs to the non-extensible deprecated version, - and disable some features, which can not be exported without - confusing older userspace tools. Since 2007/2008 all major - distributions do not enable this option, and ship no tools which - depend on the deprecated layout or this option. - - If you are using a new kernel on an older distribution, or use - older userspace tools, you might need to say Y here. Do not say Y, - if the original kernel, that came with your distribution, has - this option set to N. + help + This option adds code that switches the layout of the "block" class + devices, to not show up in /sys/class/block/, but only in + /sys/block/. + + This switch is only active when the sysfs.deprecated=1 boot option is + passed or the SYSFS_DEPRECATED_V2 option is set. + + This option allows new kernels to run on old distributions and tools, + which might get confused by /sys/class/block/. Since 2007/2008 all + major distributions and tools handle this just fine. + + Recent distributions and userspace tools after 2009/2010 depend on + the existence of /sys/class/block/, and will not work with this + option enabled. + + Only if you are using a new kernel on an old distribution, you might + need to say Y here. + +config SYSFS_DEPRECATED_V2 + bool "enabled deprecated sysfs features by default" + default n + depends on SYSFS + depends on SYSFS_DEPRECATED + help + Enable deprecated sysfs by default. + + See the CONFIG_SYSFS_DEPRECATED option for more details about this + option. + + Only if you are using a new kernel on an old distribution, you might + need to say Y here. Even then, odds are you would not need it + enabled, you can always pass the boot option if absolutely necessary. config RELAY bool "Kernel->user space relay support (formerly relayfs)"