view arch/s390/Kconfig @ 452:c7ed6fe5dca0

kexec: dont initialise regions in reserve_memory()

There is no need to initialise efi_memmap_res and boot_param_res in
reserve_memory() for the initial xen domain as it is done in
machine_kexec_setup_resources() using values from the kexec hypercall.

Signed-off-by: Simon Horman <horms@verge.net.au>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Feb 28 10:55:18 2008 +0000 (2008-02-28)
parents 3e8752eb6d9c
line source
1 #
2 # For a description of the syntax of this configuration file,
3 # see Documentation/kbuild/kconfig-language.txt.
4 #
6 config MMU
7 bool
8 default y
11 bool
12 default y
15 bool
16 default y
19 bool
22 bool
23 default y
26 bool
27 default y
30 bool
31 default y
34 bool
36 mainmenu "Linux Kernel Configuration"
38 config S390
39 bool
40 default y
42 source "init/Kconfig"
44 menu "Base setup"
46 comment "Processor type and features"
48 config 64BIT
49 bool "64 bit kernel"
50 help
51 Select this option if you have a 64 bit IBM zSeries machine
52 and want to use the 64 bit addressing mode.
54 config 32BIT
55 bool
56 default y if !64BIT
58 config SMP
59 bool "Symmetric multi-processing support"
60 ---help---
61 This enables support for systems with more than one CPU. If you have
62 a system with only one CPU, like most personal computers, say N. If
63 you have a system with more than one CPU, say Y.
65 If you say N here, the kernel will run on single and multiprocessor
66 machines, but will use only one CPU of a multiprocessor machine. If
67 you say Y here, the kernel will run on many, but not all,
68 singleprocessor machines. On a singleprocessor machine, the kernel
69 will run faster if you say N here.
71 See also the <file:Documentation/smp.txt> and the SMP-HOWTO
72 available at <http://www.tldp.org/docs.html#howto>.
74 Even if you don't know what to do here, say Y.
76 config NR_CPUS
77 int "Maximum number of CPUs (2-64)"
78 range 2 64
79 depends on SMP
80 default "32"
81 help
82 This allows you to specify the maximum number of CPUs which this
83 kernel will support. The maximum supported value is 64 and the
84 minimum value which makes sense is 2.
86 This is purely to save memory - each supported CPU adds
87 approximately sixteen kilobytes to the kernel image.
89 config HOTPLUG_CPU
90 bool "Support for hot-pluggable CPUs"
91 depends on SMP
92 select HOTPLUG
93 default n
94 help
95 Say Y here to be able to turn CPUs off and on. CPUs
96 can be controlled through /sys/devices/system/cpu/cpu#.
97 Say N if you want to disable CPU hotplug.
100 int
101 default "1000000"
103 config MATHEMU
104 bool "IEEE FPU emulation"
105 depends on MARCH_G5
106 help
107 This option is required for IEEE compliant floating point arithmetic
108 on older S/390 machines. Say Y unless you know your machine doesn't
109 need this.
111 config COMPAT
112 bool "Kernel support for 31 bit emulation"
113 depends on 64BIT
114 help
115 Select this option if you want to enable your system kernel to
116 handle system-calls from ELF binaries for 31 bit ESA. This option
117 (and some other stuff like libraries and such) is needed for
118 executing 31 bit applications. It is safe to say "Y".
121 bool
122 depends on COMPAT && SYSVIPC
123 default y
125 config AUDIT_ARCH
126 bool
127 default y
129 comment "Code generation options"
131 choice
132 prompt "Processor type"
133 default MARCH_G5
135 config MARCH_G5
136 bool "S/390 model G5 and G6"
137 depends on !64BIT
138 help
139 Select this to build a 31 bit kernel that works
140 on all S/390 and zSeries machines.
142 config MARCH_Z900
143 bool "IBM eServer zSeries model z800 and z900"
144 help
145 Select this to optimize for zSeries machines. This
146 will enable some optimizations that are not available
147 on older 31 bit only CPUs.
149 config MARCH_Z990
150 bool "IBM eServer zSeries model z890 and z990"
151 help
152 Select this enable optimizations for model z890/z990.
153 This will be slightly faster but does not work on
154 older machines such as the z900.
156 endchoice
158 config PACK_STACK
159 bool "Pack kernel stack"
160 help
161 This option enables the compiler option -mkernel-backchain if it
162 is available. If the option is available the compiler supports
163 the new stack layout which dramatically reduces the minimum stack
164 frame size. With an old compiler a non-leaf function needs a
165 minimum of 96 bytes on 31 bit and 160 bytes on 64 bit. With
166 -mkernel-backchain the minimum size drops to 16 byte on 31 bit
167 and 24 byte on 64 bit.
169 Say Y if you are unsure.
171 config SMALL_STACK
172 bool "Use 4kb/8kb for kernel stack instead of 8kb/16kb"
173 depends on PACK_STACK
174 help
175 If you say Y here and the compiler supports the -mkernel-backchain
176 option the kernel will use a smaller kernel stack size. For 31 bit
177 the reduced size is 4kb instead of 8kb and for 64 bit it is 8kb
178 instead of 16kb. This allows to run more thread on a system and
179 reduces the pressure on the memory management for higher order
180 page allocations.
182 Say N if you are unsure.
185 config CHECK_STACK
186 bool "Detect kernel stack overflow"
187 help
188 This option enables the compiler option -mstack-guard and
189 -mstack-size if they are available. If the compiler supports them
190 it will emit additional code to each function prolog to trigger
191 an illegal operation if the kernel stack is about to overflow.
193 Say N if you are unsure.
195 config STACK_GUARD
196 int "Size of the guard area (128-1024)"
197 range 128 1024
198 depends on CHECK_STACK
199 default "256"
200 help
201 This allows you to specify the size of the guard area at the lower
202 end of the kernel stack. If the kernel stack points into the guard
203 area on function entry an illegal operation is triggered. The size
204 needs to be a power of 2. Please keep in mind that the size of an
205 interrupt frame is 184 bytes for 31 bit and 328 bytes on 64 bit.
206 The minimum size for the stack guard should be 256 for 31 bit and
207 512 for 64 bit.
209 config WARN_STACK
210 bool "Emit compiler warnings for function with broken stack usage"
211 help
212 This option enables the compiler options -mwarn-framesize and
213 -mwarn-dynamicstack. If the compiler supports these options it
214 will generate warnings for function which either use alloca or
215 create a stack frame bigger then CONFIG_WARN_STACK_SIZE.
217 Say N if you are unsure.
219 config WARN_STACK_SIZE
220 int "Maximum frame size considered safe (128-2048)"
221 range 128 2048
222 depends on WARN_STACK
223 default "256"
224 help
225 This allows you to specify the maximum frame size a function may
226 have without the compiler complaining about it.
228 source "mm/Kconfig"
230 comment "I/O subsystem configuration"
233 bool "Process warning machine checks"
234 help
235 Select this option if you want the machine check handler on IBM S/390 or
236 zSeries to process warning machine checks (e.g. on power failures).
237 If unsure, say "Y".
239 config QDIO
240 tristate "QDIO support"
241 ---help---
242 This driver provides the Queued Direct I/O base support for
243 IBM mainframes.
245 For details please refer to the documentation provided by IBM at
246 <http://www10.software.ibm.com/developerworks/opensource/linux390>
248 To compile this driver as a module, choose M here: the
249 module will be called qdio.
251 If unsure, say Y.
253 config QDIO_PERF_STATS
254 bool "Performance statistics in /proc"
255 depends on QDIO
256 help
257 Say Y here to get performance statistics in /proc/qdio_perf
259 If unsure, say N.
261 config QDIO_DEBUG
262 bool "Extended debugging information"
263 depends on QDIO
264 help
265 Say Y here to get extended debugging output in
266 /sys/kernel/debug/s390dbf/qdio...
267 Warning: this option reduces the performance of the QDIO module.
269 If unsure, say N.
271 comment "Misc"
273 config PREEMPT
274 bool "Preemptible Kernel"
275 help
276 This option reduces the latency of the kernel when reacting to
277 real-time or interactive events by allowing a low priority process to
278 be preempted even if it is in kernel mode executing a system call.
279 This allows applications to run more reliably even when the system is
280 under load.
282 Say N if you are unsure.
284 config IPL
285 bool "Builtin IPL record support"
286 help
287 If you want to use the produced kernel to IPL directly from a
288 device, you have to merge a bootsector specific to the device
289 into the first bytes of the kernel. You will have to select the
290 IPL device.
292 choice
293 prompt "IPL method generated into head.S"
294 depends on IPL
295 default IPL_TAPE
296 help
297 Select "tape" if you want to IPL the image from a Tape.
299 Select "vm_reader" if you are running under VM/ESA and want
300 to IPL the image from the emulated card reader.
302 config IPL_TAPE
303 bool "tape"
305 config IPL_VM
306 bool "vm_reader"
308 endchoice
310 source "fs/Kconfig.binfmt"
312 config PROCESS_DEBUG
313 bool "Show crashed user process info"
314 help
315 Say Y to print all process fault locations to the console. This is
316 a debugging option; you probably do not want to set it unless you
317 are an S390 port maintainer.
319 config PFAULT
320 bool "Pseudo page fault support"
321 help
322 Select this option, if you want to use PFAULT pseudo page fault
323 handling under VM. If running native or in LPAR, this option
324 has no effect. If your VM does not support PFAULT, PAGEEX
325 pseudo page fault handling will be used.
326 Note that VM 4.2 supports PFAULT but has a bug in its
327 implementation that causes some problems.
328 Everybody who wants to run Linux under VM != VM4.2 should select
329 this option.
331 config SHARED_KERNEL
332 bool "VM shared kernel support"
333 help
334 Select this option, if you want to share the text segment of the
335 Linux kernel between different VM guests. This reduces memory
336 usage with lots of guests but greatly increases kernel size.
337 You should only select this option if you know what you are
338 doing and want to exploit this feature.
340 config CMM
341 tristate "Cooperative memory management"
342 help
343 Select this option, if you want to enable the kernel interface
344 to reduce the memory size of the system. This is accomplished
345 by allocating pages of memory and put them "on hold". This only
346 makes sense for a system running under VM where the unused pages
347 will be reused by VM for other guest systems. The interface
348 allows an external monitor to balance memory of many systems.
349 Everybody who wants to run Linux under VM should select this
350 option.
352 config CMM_PROC
353 bool "/proc interface to cooperative memory management"
354 depends on CMM
355 help
356 Select this option to enable the /proc interface to the
357 cooperative memory management.
359 config CMM_IUCV
360 bool "IUCV special message interface to cooperative memory management"
361 depends on CMM && (SMSGIUCV=y || CMM=SMSGIUCV)
362 help
363 Select this option to enable the special message interface to
364 the cooperative memory management.
366 config VIRT_TIMER
367 bool "Virtual CPU timer support"
368 help
369 This provides a kernel interface for virtual CPU timers.
370 Default is disabled.
373 bool "Base user process accounting on virtual cpu timer"
374 depends on VIRT_TIMER
375 help
376 Select this option to use CPU timer deltas to do user
377 process accounting.
379 config APPLDATA_BASE
380 bool "Linux - VM Monitor Stream, base infrastructure"
381 depends on PROC_FS && VIRT_TIMER=y
382 help
383 This provides a kernel interface for creating and updating z/VM APPLDATA
384 monitor records. The monitor records are updated at certain time
385 intervals, once the timer is started.
386 Writing 1 or 0 to /proc/appldata/timer starts(1) or stops(0) the timer,
387 i.e. enables or disables monitoring on the Linux side.
388 A custom interval value (in seconds) can be written to
389 /proc/appldata/interval.
391 Defaults are 60 seconds interval and timer off.
392 The /proc entries can also be read from, showing the current settings.
394 config APPLDATA_MEM
395 tristate "Monitor memory management statistics"
396 depends on APPLDATA_BASE
397 help
398 This provides memory management related data to the Linux - VM Monitor
399 Stream, like paging/swapping rate, memory utilisation, etc.
400 Writing 1 or 0 to /proc/appldata/memory creates(1) or removes(0) a z/VM
401 APPLDATA monitor record, i.e. enables or disables monitoring this record
402 on the z/VM side.
404 Default is disabled.
405 The /proc entry can also be read from, showing the current settings.
407 This can also be compiled as a module, which will be called
408 appldata_mem.o.
410 config APPLDATA_OS
411 tristate "Monitor OS statistics"
412 depends on APPLDATA_BASE
413 help
414 This provides OS related data to the Linux - VM Monitor Stream, like
415 CPU utilisation, etc.
416 Writing 1 or 0 to /proc/appldata/os creates(1) or removes(0) a z/VM
417 APPLDATA monitor record, i.e. enables or disables monitoring this record
418 on the z/VM side.
420 Default is disabled.
421 This can also be compiled as a module, which will be called
422 appldata_os.o.
425 tristate "Monitor overall network statistics"
426 depends on APPLDATA_BASE
427 help
428 This provides network related data to the Linux - VM Monitor Stream,
429 currently there is only a total sum of network I/O statistics, no
430 per-interface data.
431 Writing 1 or 0 to /proc/appldata/net_sum creates(1) or removes(0) a z/VM
432 APPLDATA monitor record, i.e. enables or disables monitoring this record
433 on the z/VM side.
435 Default is disabled.
436 This can also be compiled as a module, which will be called
437 appldata_net_sum.o.
439 config NO_IDLE_HZ
440 bool "No HZ timer ticks in idle"
441 help
442 Switches the regular HZ timer off when the system is going idle.
443 This helps z/VM to detect that the Linux system is idle. VM can
444 then "swap-out" this guest which reduces memory usage. It also
445 reduces the overhead of idle systems.
447 The HZ timer can be switched on/off via /proc/sys/kernel/hz_timer.
448 hz_timer=0 means HZ timer is disabled. hz_timer=1 means HZ
449 timer is active.
451 config NO_IDLE_HZ_INIT
452 bool "HZ timer in idle off by default"
453 depends on NO_IDLE_HZ
454 help
455 The HZ timer is switched off in idle by default. That means the
456 HZ timer is already disabled at boot time.
458 config S390_HYPFS_FS
459 bool "s390 hypervisor file system support"
461 default y
462 help
463 This is a virtual file system intended to provide accounting
464 information in an s390 hypervisor environment.
466 config KEXEC
467 bool "kexec system call (EXPERIMENTAL)"
468 depends on EXPERIMENTAL
469 help
470 kexec is a system call that implements the ability to shutdown your
471 current kernel, and to start another kernel. It is like a reboot
472 but is independent of hardware/microcode support.
474 endmenu
476 source "net/Kconfig"
478 config PCMCIA
479 bool
480 default n
482 source "drivers/base/Kconfig"
484 source "drivers/connector/Kconfig"
486 source "drivers/scsi/Kconfig"
488 source "drivers/s390/Kconfig"
490 source "drivers/net/Kconfig"
492 source "fs/Kconfig"
494 source "arch/s390/oprofile/Kconfig"
496 source "arch/s390/Kconfig.debug"
498 source "security/Kconfig"
500 source "crypto/Kconfig"
502 source "lib/Kconfig"