depends on (MWINCHIP3D || MWINCHIP2 || MWINCHIPC6) && MTRR
default y
+config X86_4G
+ bool "4 GB kernel-space and 4 GB user-space virtual memory support"
+ help
+ This option is only useful for systems that have more than 1 GB
+ of RAM.
+
+ The default kernel VM layout leaves 1 GB of virtual memory for
+ kernel-space mappings, and 3 GB of VM for user-space applications.
+ This option ups both the kernel-space VM and the user-space VM to
+ 4 GB.
+
+ The cost of this option is additional TLB flushes done at
+ system-entry points that transition from user-mode into kernel-mode.
+ I.e. system calls and page faults, and IRQs that interrupt user-mode
+ code. There's also additional overhead to kernel operations that copy
+ memory to/from user-space. The overhead from this is hard to tell and
+ depends on the workload - it can be anything from no visible overhead
+ to 20-30% overhead. A good rule of thumb is to count with a runtime
+ overhead of 20%.
+
+ The upside is the much increased kernel-space VM, which more than
+ quadruples the maximum amount of RAM supported. Kernels compiled with
+ this option boot on 64GB of RAM and still have more than 3.1 GB of
+ 'lowmem' left. Another bonus is that highmem IO bouncing decreases,
+ if used with drivers that still use bounce-buffers.
+
+ There's also a 33% increase in user-space VM size - database
+ applications might see a boost from this.
+
+ But the cost of the TLB flushes and the runtime overhead has to be
+ weighed against the bonuses offered by the larger VM spaces. The
+ dividing line depends on the actual workload - there might be 4 GB
+ systems that benefit from this option. Systems with less than 4 GB
+ of RAM will rarely see a benefit from this option - but it's not
+ out of question, the exact circumstances have to be considered.
+
+config X86_SWITCH_PAGETABLES
+ def_bool X86_4G
+
+config X86_4G_VM_LAYOUT
+ def_bool X86_4G
+
+config X86_UACCESS_INDIRECT
+ def_bool X86_4G
+
+config X86_HIGH_ENTRY
+ def_bool X86_4G
+
config HPET_TIMER
bool "HPET Timer Support"
help
Say Y here if you are building a kernel for a desktop, embedded
or real-time system. Say N if you are unsure.
+config PREEMPT_VOLUNTARY
+ bool "Voluntary Kernel Preemption"
+ depends on !PREEMPT
+ default y
+ help
+ This option reduces the latency of the kernel by adding more
+ "explicit preemption points" to the kernel code. These new
+ preemption points have been selected to minimize the maximum
+ latency of rescheduling, providing faster application reactions.
+
+ Say Y here if you are building a kernel for a desktop system.
+ Say N if you are unsure.
+
config X86_UP_APIC
bool "Local APIC support on uniprocessors" if !SMP
depends on !(X86_VISWS || X86_VOYAGER)
menu "Kernel hacking"
+config CRASH_DUMP
+ tristate "Crash dump support (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ default n
+ ---help---
+ Say Y here to enable saving an image of system memory when a panic
+ or other error occurs. Dumps can also be forced with the SysRq+d
+ key if MAGIC_SYSRQ is enabled.
+
+config CRASH_DUMP_BLOCKDEV
+ tristate "Crash dump block device driver"
+ depends on CRASH_DUMP
+ help
+ Say Y to allow saving crash dumps directly to a disk device.
+
+config CRASH_DUMP_NETDEV
+ tristate "Crash dump network device driver"
+ depends on CRASH_DUMP
+ help
+ Say Y to allow saving crash dumps over a network device.
+
+config CRASH_DUMP_MEMDEV
+ bool "Crash dump staged memory driver"
+ depends on CRASH_DUMP
+ help
+ Say Y to allow intermediate saving crash dumps in spare
+ memory pages which would then be written out to disk
+ later.
+
+config CRASH_DUMP_SOFTBOOT
+ bool "Save crash dump across a soft reboot"
+ depends on CRASH_DUMP_MEMDEV
+ help
+ Say Y to allow a crash dump to be preserved in memory
+ pages across a soft reboot and written out to disk
+ thereafter. For this to work, CRASH_DUMP must be
+ configured as part of the kernel (not as a module).
+
+config CRASH_DUMP_COMPRESS_RLE
+ tristate "Crash dump RLE compression"
+ depends on CRASH_DUMP
+ help
+ Say Y to allow saving dumps with Run Length Encoding compression.
+
+config CRASH_DUMP_COMPRESS_GZIP
+ tristate "Crash dump GZIP compression"
+ select ZLIB_INFLATE
+ select ZLIB_DEFLATE
+ depends on CRASH_DUMP
+ help
+ Say Y to allow saving dumps with Gnu Zip compression.
+
config DEBUG_KERNEL
bool "Kernel debugging"
help
If you don't debug the kernel, you can say N, but we may not be able
to solve problems without frame pointers.
-config 4KSTACKS
- bool "Use 4Kb for kernel stacks instead of 8Kb"
- help
- If you say Y here the kernel will use a 4Kb stacksize for the
- kernel stack attached to each process/thread. This facilitates
- running more threads on a system and also reduces the pressure
- on the VM subsystem for higher order allocations. This option
- will also use IRQ stacks to compensate for the reduced stackspace.
-
config X86_FIND_SMP_CONFIG
bool
depends on X86_LOCAL_APIC || X86_VOYAGER
endmenu
+source "kernel/vserver/Kconfig"
+
source "security/Kconfig"
source "crypto/Kconfig"
git://git.onelab.eu / linux-2.6.git / blobdiff