blob: 2880abf8a269e751e1e8ba5535ae194cda34ea98 [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
162config USE_GENERIC_SMP_HELPERS
Jan Beulich9ba16082008-10-15 22:01:38 -0700163 bool
David Brownell9483a572008-07-23 21:26:48 -0700164
Heiko Carstensf850c30c2010-02-10 17:25:17 +0100165config HAVE_REGS_AND_STACK_ACCESS_API
166 bool
Heiko Carstense01292b2010-02-18 14:25:21 +0100167 help
168 This symbol should be selected by an architecure if it supports
169 the API needed to access registers and stack entries from pt_regs,
170 declared in asm/ptrace.h
171 For example the kprobes-based event tracer needs this API.
Heiko Carstensf850c30c2010-02-10 17:25:17 +0100172
David Brownell9483a572008-07-23 21:26:48 -0700173config HAVE_CLK
Jan Beulich9ba16082008-10-15 22:01:38 -0700174 bool
David Brownell9483a572008-07-23 21:26:48 -0700175 help
176 The <linux/clk.h> calls support software clock gating and
177 thus are a key power management tool on many systems.
178
Joerg Roedel5ee00bd2009-01-09 12:14:24 +0100179config HAVE_DMA_API_DEBUG
180 bool
Heiko Carstens36cd3c92009-04-09 18:48:34 +0200181
K.Prasad62a038d2009-06-01 23:43:33 +0530182config HAVE_HW_BREAKPOINT
183 bool
Frederic Weisbecker99e8c5a2009-12-17 01:33:54 +0100184 depends on PERF_EVENTS
K.Prasad62a038d2009-06-01 23:43:33 +0530185
Frederic Weisbecker01027522010-04-11 18:55:56 +0200186config HAVE_MIXED_BREAKPOINTS_REGS
187 bool
188 depends on HAVE_HW_BREAKPOINT
189 help
190 Depending on the arch implementation of hardware breakpoints,
191 some of them have separate registers for data and instruction
192 breakpoints addresses, others have mixed registers to store
193 them but define the access type in a control register.
194 Select this option if your arch implements breakpoints under the
195 latter fashion.
196
Avi Kivity7c68af62009-09-19 09:40:22 +0300197config HAVE_USER_RETURN_NOTIFIER
198 bool
Ingo Molnara1922ed2009-09-07 08:19:51 +0200199
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200200config HAVE_PERF_EVENTS_NMI
201 bool
Frederic Weisbecker23637d42010-05-15 23:15:20 +0200202 help
203 System hardware can generate an NMI using the perf event
204 subsystem. Also has support for calculating CPU cycle events
205 to determine how many clock cycles in a given period.
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200206
Jason Baronbf5438fc2010-09-17 11:09:00 -0400207config HAVE_ARCH_JUMP_LABEL
208 bool
209
Gerald Schaefer335d7af2010-11-22 15:47:36 +0100210config HAVE_ARCH_MUTEX_CPU_RELAX
211 bool
212
Peter Zijlstra26723912011-05-24 17:12:00 -0700213config HAVE_RCU_TABLE_FREE
214 bool
215
Huang Yingdf013ff2011-07-13 13:14:22 +0800216config ARCH_HAVE_NMI_SAFE_CMPXCHG
217 bool
218
Heiko Carstens43570fd2012-01-12 17:17:27 -0800219config HAVE_ALIGNED_STRUCT_PAGE
220 bool
221 help
222 This makes sure that struct pages are double word aligned and that
223 e.g. the SLUB allocator can perform double word atomic operations
224 on a struct page for better performance. However selecting this
225 might increase the size of a struct page by a word.
226
Heiko Carstens41561532012-01-12 17:17:30 -0800227config HAVE_CMPXCHG_LOCAL
228 bool
229
Heiko Carstens25654092012-01-12 17:17:33 -0800230config HAVE_CMPXCHG_DOUBLE
231 bool
232
Chris Metcalf48b25c42012-03-15 13:13:38 -0400233config ARCH_WANT_OLD_COMPAT_IPC
234 bool
235
Peter Oberparleiter2521f2c2009-06-17 16:28:08 -0700236source "kernel/gcov/Kconfig"