queues every message has a priority which decides about succession
of receiving it by a process. If you want to compile and run
programs written e.g. for Solaris with use of its POSIX message
- queues (functions mq_*) say Y here. To use this feature you will
- also need mqueue library, available from
- <http://www.mat.uni.torun.pl/~wrona/posix_ipc/>
+ queues (functions mq_*) say Y here.
POSIX message queues are visible as a filesystem called 'mqueue'
and can be mounted somewhere if you want to do filesystem
releases.
If enabled, this option will also move any device structures
- that belong to a class, back into the /sys/class heirachy, in
+ that belong to a class, back into the /sys/class hierarchy, in
order to support older versions of udev.
If you are using a distro that was released in 2006 or later,
support for "fast userspace mutexes". The resulting kernel may not
run glibc-based applications correctly.
+config ANON_INODES
+ bool "Enable anonymous inode source" if EMBEDDED
+ default y
+ help
+ Anonymous inode source for pseudo-files like epoll, signalfd,
+ timerfd and eventfd.
+
+ If unsure, say Y.
+
config EPOLL
bool "Enable eventpoll support" if EMBEDDED
default y
+ depends on ANON_INODES
help
Disabling this option will cause the kernel to be built without
support for epoll family of system calls.
+config SIGNALFD
+ bool "Enable signalfd() system call" if EMBEDDED
+ depends on ANON_INODES
+ default y
+ help
+ Enable the signalfd() system call that allows to receive signals
+ on a file descriptor.
+
+ If unsure, say Y.
+
+config TIMERFD
+ bool "Enable timerfd() system call" if EMBEDDED
+ depends on ANON_INODES
+ default y
+ help
+ Enable the timerfd() system call that allows to receive timer
+ events on a file descriptor.
+
+ If unsure, say Y.
+
+config EVENTFD
+ bool "Enable eventfd() system call" if EMBEDDED
+ depends on ANON_INODES
+ default y
+ help
+ Enable the eventfd() system call that allows to receive both
+ kernel notification (ie. KAIO) or userspace notifications.
+
+ If unsure, say Y.
+
config SHMEM
bool "Use full shmem filesystem" if EMBEDDED
default y
config SLUB_DEBUG
default y
bool "Enable SLUB debugging support" if EMBEDDED
+ depends on SLUB
help
SLUB has extensive debug support features. Disabling these can
result in significant savings in code size. This also disables
a slab allocator.
config SLUB
- depends on EXPERIMENTAL && !ARCH_USES_SLAB_PAGE_STRUCT
bool "SLUB (Unqueued Allocator)"
help
SLUB is a slab allocator that minimizes cache line usage
and has enhanced diagnostics.
config SLOB
-#
-# SLOB does not support SMP because SLAB_DESTROY_BY_RCU is unsupported
-#
- depends on EMBEDDED && !SMP && !SPARSEMEM
+ depends on EMBEDDED && !SPARSEMEM
bool "SLOB (Simple Allocator)"
help
SLOB replaces the SLAB allocator with a drastically simpler
- allocator. SLOB is more space efficient that SLAB but does not
+ allocator. SLOB is more space efficient than SLAB but does not
scale well (single lock for all operations) and is also highly
susceptible to fragmentation. SLUB can accomplish a higher object
density. It is usually better to use SLUB instead of SLOB.