blob: 366ec06a5185f0a59a7e5069357dbdb3da5a08c8 [file] [log] [blame]
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -05001#
2# General architecture dependent options
3#
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05004
5config OPROFILE
Robert Richterb309a292010-02-26 15:01:23 +01006 tristate "OProfile system profiling"
Mathieu Desnoyers125e5642008-02-02 15:10:36 -05007 depends on PROFILING
8 depends on HAVE_OPROFILE
Ingo Molnard69d59f2008-12-12 09:38:57 +01009 select RING_BUFFER
Christian Borntraeger9a5963e2009-09-16 21:56:49 +020010 select RING_BUFFER_ALLOW_SWAP
Mathieu Desnoyers125e5642008-02-02 15:10:36 -050011 help
12 OProfile is a profiling system capable of profiling the
13 whole system, include the kernel, kernel modules, libraries,
14 and applications.
15
16 If unsure, say N.
17
Jason Yeh4d4036e2009-07-08 13:49:38 +020018config OPROFILE_EVENT_MULTIPLEX
19 bool "OProfile multiplexing support (EXPERIMENTAL)"
20 default n
21 depends on OPROFILE && X86
22 help
23 The number of hardware counters is limited. The multiplexing
24 feature enables OProfile to gather more events than counters
25 are provided by the hardware. This is realized by switching
26 between events at an user specified time interval.
27
28 If unsure, say N.
29
Mathieu Desnoyers125e5642008-02-02 15:10:36 -050030config HAVE_OPROFILE
Jan Beulich9ba16082008-10-15 22:01:38 -070031 bool
Mathieu Desnoyers125e5642008-02-02 15:10:36 -050032
Robert Richterdcfce4a2011-10-11 17:11:08 +020033config OPROFILE_NMI_TIMER
34 def_bool y
35 depends on PERF_EVENTS && HAVE_PERF_EVENTS_NMI
36
Mathieu Desnoyers125e5642008-02-02 15:10:36 -050037config KPROBES
38 bool "Kprobes"
Masami Hiramatsu05ed1602010-09-13 19:25:41 +090039 depends on MODULES
Mathieu Desnoyers125e5642008-02-02 15:10:36 -050040 depends on HAVE_KPROBES
Masami Hiramatsu05ed1602010-09-13 19:25:41 +090041 select KALLSYMS
Mathieu Desnoyers125e5642008-02-02 15:10:36 -050042 help
43 Kprobes allows you to trap at almost any kernel address and
44 execute a callback function. register_kprobe() establishes
45 a probepoint and specifies the callback. Kprobes is useful
46 for kernel debugging, non-intrusive instrumentation and testing.
47 If in doubt, say "N".
48
Steven Rostedt45f81b12010-10-29 12:33:43 -040049config JUMP_LABEL
Ingo Molnarc5905af2012-02-24 08:31:31 +010050 bool "Optimize very unlikely/likely branches"
Steven Rostedt45f81b12010-10-29 12:33:43 -040051 depends on HAVE_ARCH_JUMP_LABEL
52 help
Ingo Molnarc5905af2012-02-24 08:31:31 +010053 This option enables a transparent branch optimization that
54 makes certain almost-always-true or almost-always-false branch
55 conditions even cheaper to execute within the kernel.
Steven Rostedt45f81b12010-10-29 12:33:43 -040056
Ingo Molnarc5905af2012-02-24 08:31:31 +010057 Certain performance-sensitive kernel code, such as trace points,
58 scheduler functionality, networking code and KVM have such
59 branches and include support for this optimization technique.
60
61 If it is detected that the compiler has support for "asm goto",
62 the kernel will compile such branches with just a nop
63 instruction. When the condition flag is toggled to true, the
64 nop will be converted to a jump instruction to execute the
65 conditional block of instructions.
66
67 This technique lowers overhead and stress on the branch prediction
68 of the processor and generally makes the kernel faster. The update
69 of the condition is slower, but those are always very rare.
70
71 ( On 32-bit x86, the necessary options added to the compiler
72 flags may increase the size of the kernel slightly. )
Steven Rostedt45f81b12010-10-29 12:33:43 -040073
Masami Hiramatsuafd66252010-02-25 08:34:07 -050074config OPTPROBES
Masami Hiramatsu5cc718b2010-03-15 13:00:54 -040075 def_bool y
76 depends on KPROBES && HAVE_OPTPROBES
Masami Hiramatsuafd66252010-02-25 08:34:07 -050077 depends on !PREEMPT
Masami Hiramatsuafd66252010-02-25 08:34:07 -050078
Srikar Dronamraju2b144492012-02-09 14:56:42 +053079config UPROBES
Ingo Molnar7b2d81d2012-02-17 09:27:41 +010080 bool "Transparent user-space probes (EXPERIMENTAL)"
Srikar Dronamrajuec83db02012-05-08 16:41:26 +053081 depends on UPROBE_EVENT && PERF_EVENTS
Srikar Dronamraju2b144492012-02-09 14:56:42 +053082 default n
83 help
Ingo Molnar7b2d81d2012-02-17 09:27:41 +010084 Uprobes is the user-space counterpart to kprobes: they
85 enable instrumentation applications (such as 'perf probe')
86 to establish unintrusive probes in user-space binaries and
87 libraries, by executing handler functions when the probes
88 are hit by user-space applications.
89
90 ( These probes come in the form of single-byte breakpoints,
91 managed by the kernel and kept transparent to the probed
92 application. )
Srikar Dronamraju2b144492012-02-09 14:56:42 +053093
94 If in doubt, say "N".
95
Johannes Berg58340a02008-07-25 01:45:33 -070096config HAVE_EFFICIENT_UNALIGNED_ACCESS
Jan Beulich9ba16082008-10-15 22:01:38 -070097 bool
Johannes Berg58340a02008-07-25 01:45:33 -070098 help
99 Some architectures are unable to perform unaligned accesses
100 without the use of get_unaligned/put_unaligned. Others are
101 unable to perform such accesses efficiently (e.g. trap on
102 unaligned access and require fixing it up in the exception
103 handler.)
104
105 This symbol should be selected by an architecture if it can
106 perform unaligned accesses efficiently to allow different
107 code paths to be selected for these cases. Some network
108 drivers, for example, could opt to not fix up alignment
109 problems with received packets if doing so would not help
110 much.
111
112 See Documentation/unaligned-memory-access.txt for more
113 information on the topic of unaligned memory accesses.
114
Heiko Carstens1a94bc32009-01-14 14:13:59 +0100115config HAVE_SYSCALL_WRAPPERS
116 bool
117
Ananth N Mavinakayanahalli9edddaa2008-03-04 14:28:37 -0800118config KRETPROBES
119 def_bool y
120 depends on KPROBES && HAVE_KRETPROBES
121
Avi Kivity7c68af62009-09-19 09:40:22 +0300122config USER_RETURN_NOTIFIER
123 bool
124 depends on HAVE_USER_RETURN_NOTIFIER
125 help
126 Provide a kernel-internal notification when a cpu is about to
127 switch to user mode.
128
Rik van Riel28b2ee22008-07-23 21:27:05 -0700129config HAVE_IOREMAP_PROT
Jan Beulich9ba16082008-10-15 22:01:38 -0700130 bool
Rik van Riel28b2ee22008-07-23 21:27:05 -0700131
Mathieu Desnoyers125e5642008-02-02 15:10:36 -0500132config HAVE_KPROBES
Jan Beulich9ba16082008-10-15 22:01:38 -0700133 bool
Ananth N Mavinakayanahalli9edddaa2008-03-04 14:28:37 -0800134
135config HAVE_KRETPROBES
Jan Beulich9ba16082008-10-15 22:01:38 -0700136 bool
Arthur Kepner74bc7ce2008-04-29 01:00:30 -0700137
Masami Hiramatsuafd66252010-02-25 08:34:07 -0500138config HAVE_OPTPROBES
139 bool
Cong Wangd314d742012-03-23 15:01:51 -0700140
141config HAVE_NMI_WATCHDOG
142 bool
Roland McGrath1f5a4ad2008-07-25 19:45:57 -0700143#
144# An arch should select this if it provides all these things:
145#
146# task_pt_regs() in asm/processor.h or asm/ptrace.h
147# arch_has_single_step() if there is hardware single-step support
148# arch_has_block_step() if there is hardware block-step support
Roland McGrath1f5a4ad2008-07-25 19:45:57 -0700149# asm/syscall.h supplying asm-generic/syscall.h interface
150# linux/regset.h user_regset interfaces
151# CORE_DUMP_USE_REGSET #define'd in linux/elf.h
152# TIF_SYSCALL_TRACE calls tracehook_report_syscall_{entry,exit}
153# TIF_NOTIFY_RESUME calls tracehook_notify_resume()
154# signal delivery calls tracehook_signal_handler()
155#
156config HAVE_ARCH_TRACEHOOK
Jan Beulich9ba16082008-10-15 22:01:38 -0700157 bool
Roland McGrath1f5a4ad2008-07-25 19:45:57 -0700158
Arthur Kepner74bc7ce2008-04-29 01:00:30 -0700159config HAVE_DMA_ATTRS
Jan Beulich9ba16082008-10-15 22:01:38 -0700160 bool
Jens Axboe3d442232008-06-26 11:21:34 +0200161
Marek Szyprowskic64be2b2011-12-29 13:09:51 +0100162config HAVE_DMA_CONTIGUOUS
163 bool
164
Jens Axboe3d442232008-06-26 11:21:34 +0200165config USE_GENERIC_SMP_HELPERS
Jan Beulich9ba16082008-10-15 22:01:38 -0700166 bool
David Brownell9483a572008-07-23 21:26:48 -0700167
Thomas Gleixner29d5e042012-04-20 13:05:45 +0000168config GENERIC_SMP_IDLE_THREAD
169 bool
170
Thomas Gleixnera6359d12012-05-03 09:03:02 +0000171# Select if arch init_task initializer is different to init/init_task.c
172config ARCH_INIT_TASK
Thomas Gleixnera4a2eb42012-05-03 09:02:48 +0000173 bool
174
Thomas Gleixnerf5e10282012-05-05 15:05:48 +0000175# Select if arch has its private alloc_task_struct() function
176config ARCH_TASK_STRUCT_ALLOCATOR
177 bool
178
179# Select if arch has its private alloc_thread_info() function
180config ARCH_THREAD_INFO_ALLOCATOR
181 bool
182
Heiko Carstensf850c30c2010-02-10 17:25:17 +0100183config HAVE_REGS_AND_STACK_ACCESS_API
184 bool
Heiko Carstense01292b2010-02-18 14:25:21 +0100185 help
186 This symbol should be selected by an architecure if it supports
187 the API needed to access registers and stack entries from pt_regs,
188 declared in asm/ptrace.h
189 For example the kprobes-based event tracer needs this API.
Heiko Carstensf850c30c2010-02-10 17:25:17 +0100190
David Brownell9483a572008-07-23 21:26:48 -0700191config HAVE_CLK
Jan Beulich9ba16082008-10-15 22:01:38 -0700192 bool
David Brownell9483a572008-07-23 21:26:48 -0700193 help
194 The <linux/clk.h> calls support software clock gating and
195 thus are a key power management tool on many systems.
196
Joerg Roedel5ee00bd2009-01-09 12:14:24 +0100197config HAVE_DMA_API_DEBUG
198 bool
Heiko Carstens36cd3c92009-04-09 18:48:34 +0200199
K.Prasad62a038d2009-06-01 23:43:33 +0530200config HAVE_HW_BREAKPOINT
201 bool
Frederic Weisbecker99e8c5a2009-12-17 01:33:54 +0100202 depends on PERF_EVENTS
K.Prasad62a038d2009-06-01 23:43:33 +0530203
Frederic Weisbecker01027522010-04-11 18:55:56 +0200204config HAVE_MIXED_BREAKPOINTS_REGS
205 bool
206 depends on HAVE_HW_BREAKPOINT
207 help
208 Depending on the arch implementation of hardware breakpoints,
209 some of them have separate registers for data and instruction
210 breakpoints addresses, others have mixed registers to store
211 them but define the access type in a control register.
212 Select this option if your arch implements breakpoints under the
213 latter fashion.
214
Avi Kivity7c68af62009-09-19 09:40:22 +0300215config HAVE_USER_RETURN_NOTIFIER
216 bool
Ingo Molnara1922ed2009-09-07 08:19:51 +0200217
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200218config HAVE_PERF_EVENTS_NMI
219 bool
Frederic Weisbecker23637d42010-05-15 23:15:20 +0200220 help
221 System hardware can generate an NMI using the perf event
222 subsystem. Also has support for calculating CPU cycle events
223 to determine how many clock cycles in a given period.
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200224
Jiri Olsac5e63192012-08-07 15:20:36 +0200225config HAVE_PERF_REGS
226 bool
227 help
228 Support selective register dumps for perf events. This includes
229 bit-mapping of each registers and a unique architecture id.
230
Jiri Olsac5ebced2012-08-07 15:20:40 +0200231config HAVE_PERF_USER_STACK_DUMP
232 bool
233 help
234 Support user stack dumps for perf event samples. This needs
235 access to the user stack pointer which is not unified across
236 architectures.
237
Jason Baronbf5438fc2010-09-17 11:09:00 -0400238config HAVE_ARCH_JUMP_LABEL
239 bool
240
Gerald Schaefer335d7af2010-11-22 15:47:36 +0100241config HAVE_ARCH_MUTEX_CPU_RELAX
242 bool
243
Peter Zijlstra26723912011-05-24 17:12:00 -0700244config HAVE_RCU_TABLE_FREE
245 bool
246
Huang Yingdf013ff2011-07-13 13:14:22 +0800247config ARCH_HAVE_NMI_SAFE_CMPXCHG
248 bool
249
Heiko Carstens43570fd2012-01-12 17:17:27 -0800250config HAVE_ALIGNED_STRUCT_PAGE
251 bool
252 help
253 This makes sure that struct pages are double word aligned and that
254 e.g. the SLUB allocator can perform double word atomic operations
255 on a struct page for better performance. However selecting this
256 might increase the size of a struct page by a word.
257
Heiko Carstens41561532012-01-12 17:17:30 -0800258config HAVE_CMPXCHG_LOCAL
259 bool
260
Heiko Carstens25654092012-01-12 17:17:33 -0800261config HAVE_CMPXCHG_DOUBLE
262 bool
263
Will Deaconc1d7e012012-07-30 14:42:46 -0700264config ARCH_WANT_IPC_PARSE_VERSION
265 bool
266
267config ARCH_WANT_COMPAT_IPC_PARSE_VERSION
268 bool
269
Chris Metcalf48b25c42012-03-15 13:13:38 -0400270config ARCH_WANT_OLD_COMPAT_IPC
Will Deaconc1d7e012012-07-30 14:42:46 -0700271 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
Chris Metcalf48b25c42012-03-15 13:13:38 -0400272 bool
273
Al Viro2aa3a7f2012-09-21 19:55:31 -0400274config GENERIC_KERNEL_THREAD
275 bool
276
Al Viroa74fb732012-10-10 21:28:25 -0400277config GENERIC_KERNEL_EXECVE
278 bool
279
Will Drewrye2cfabdf2012-04-12 16:47:57 -0500280config HAVE_ARCH_SECCOMP_FILTER
281 bool
282 help
Will Drewryfb0fadf2012-04-12 16:48:02 -0500283 An arch should select this symbol if it provides all of these things:
Will Drewrybb6ea432012-04-12 16:48:01 -0500284 - syscall_get_arch()
285 - syscall_get_arguments()
286 - syscall_rollback()
287 - syscall_set_return_value()
Will Drewryfb0fadf2012-04-12 16:48:02 -0500288 - SIGSYS siginfo_t support
289 - secure_computing is called from a ptrace_event()-safe context
290 - secure_computing return value is checked and a return value of -1
291 results in the system call being skipped immediately.
Will Drewrye2cfabdf2012-04-12 16:47:57 -0500292
293config SECCOMP_FILTER
294 def_bool y
295 depends on HAVE_ARCH_SECCOMP_FILTER && SECCOMP && NET
296 help
297 Enable tasks to build secure computing environments defined
298 in terms of Berkeley Packet Filter programs which implement
299 task-defined system call filtering polices.
300
301 See Documentation/prctl/seccomp_filter.txt for details.
302
Frederic Weisbecker2b1d5022012-07-11 20:26:30 +0200303config HAVE_RCU_USER_QS
304 bool
305 help
306 Provide kernel entry/exit hooks necessary for userspace
307 RCU extended quiescent state. Syscalls need to be wrapped inside
308 rcu_user_exit()-rcu_user_enter() through the slow path using
309 TIF_NOHZ flag. Exceptions handlers must be wrapped as well. Irqs
310 are already protected inside rcu_irq_enter/rcu_irq_exit() but
311 preemption or signal handling on irq exit still need to be protected.
312
Frederic Weisbeckerb9527412012-06-16 15:39:34 +0200313config HAVE_VIRT_CPU_ACCOUNTING
314 bool
315
Frederic Weisbeckerfdf9c352012-09-09 14:56:31 +0200316config HAVE_IRQ_TIME_ACCOUNTING
317 bool
318 help
319 Archs need to ensure they use a high enough resolution clock to
320 support irq time accounting and then call enable_sched_clock_irqtime().
321
Gerald Schaefer15626062012-10-08 16:30:04 -0700322config HAVE_ARCH_TRANSPARENT_HUGEPAGE
323 bool
324
David Howells786d35d2012-09-28 14:31:03 +0930325config HAVE_MOD_ARCH_SPECIFIC
326 bool
327 help
328 The arch uses struct mod_arch_specific to store data. Many arches
329 just need a simple module loader without arch specific data - those
330 should not enable this.
331
332config MODULES_USE_ELF_RELA
333 bool
334 help
335 Modules only use ELF RELA relocations. Modules with ELF REL
336 relocations will give an error.
337
338config MODULES_USE_ELF_REL
339 bool
340 help
341 Modules only use ELF REL relocations. Modules with ELF RELA
342 relocations will give an error.
343
Peter Oberparleiter2521f2c2009-06-17 16:28:08 -0700344source "kernel/gcov/Kconfig"