diff options
Diffstat (limited to 'init/Kconfig')
| -rw-r--r-- | init/Kconfig | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/init/Kconfig b/init/Kconfig index eb4b33725db1..a23da9f01803 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -334,6 +334,15 @@ config TREE_PREEMPT_RCU is also required. It also scales down nicely to smaller systems. +config TINY_RCU + bool "UP-only small-memory-footprint RCU" + depends on !SMP + help + This option selects the RCU implementation that is + designed for UP systems from which real-time response + is not required. This option greatly reduces the + memory footprint of RCU. + endchoice config RCU_TRACE @@ -606,7 +615,7 @@ config SYSFS_DEPRECATED bool config SYSFS_DEPRECATED_V2 - bool "enable deprecated sysfs features which may confuse old userspace tools" + bool "enable deprecated sysfs features to support old userspace tools" depends on SYSFS default n select SYSFS_DEPRECATED @@ -754,6 +763,7 @@ config UID16 config SYSCTL_SYSCALL bool "Sysctl syscall support" if EMBEDDED + depends on PROC_SYSCTL default y select SYSCTL ---help--- @@ -1069,6 +1079,28 @@ config SLOB endchoice +config MMAP_ALLOW_UNINITIALIZED + bool "Allow mmapped anonymous memory to be uninitialized" + depends on EMBEDDED && !MMU + default n + help + Normally, and according to the Linux spec, anonymous memory obtained + from mmap() has it's contents cleared before it is passed to + userspace. Enabling this config option allows you to request that + mmap() skip that if it is given an MAP_UNINITIALIZED flag, thus + providing a huge performance boost. If this option is not enabled, + then the flag will be ignored. + + This is taken advantage of by uClibc's malloc(), and also by + ELF-FDPIC binfmt's brk and stack allocator. + + Because of the obvious security issues, this option should only be + enabled on embedded devices where you control what is run in + userspace. Since that isn't generally a problem on no-MMU systems, + it is normally safe to say Y here. + + See Documentation/nommu-mmap.txt for more information. + config PROFILING bool "Profiling support (EXPERIMENTAL)" help @@ -1220,3 +1252,4 @@ source "block/Kconfig" config PREEMPT_NOTIFIERS bool +source "kernel/Kconfig.locks" |