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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
Johannes Berg58340a02008-07-25 01:45:33 -070079config HAVE_EFFICIENT_UNALIGNED_ACCESS
Jan Beulich9ba16082008-10-15 22:01:38 -070080 bool
Johannes Berg58340a02008-07-25 01:45:33 -070081 help
82 Some architectures are unable to perform unaligned accesses
83 without the use of get_unaligned/put_unaligned. Others are
84 unable to perform such accesses efficiently (e.g. trap on
85 unaligned access and require fixing it up in the exception
86 handler.)
87
88 This symbol should be selected by an architecture if it can
89 perform unaligned accesses efficiently to allow different
90 code paths to be selected for these cases. Some network
91 drivers, for example, could opt to not fix up alignment
92 problems with received packets if doing so would not help
93 much.
94
95 See Documentation/unaligned-memory-access.txt for more
96 information on the topic of unaligned memory accesses.
97
Heiko Carstens1a94bc32009-01-14 14:13:59 +010098config HAVE_SYSCALL_WRAPPERS
99 bool
100
Ananth N Mavinakayanahalli9edddaa2008-03-04 14:28:37 -0800101config KRETPROBES
102 def_bool y
103 depends on KPROBES && HAVE_KRETPROBES
104
Avi Kivity7c68af62009-09-19 09:40:22 +0300105config USER_RETURN_NOTIFIER
106 bool
107 depends on HAVE_USER_RETURN_NOTIFIER
108 help
109 Provide a kernel-internal notification when a cpu is about to
110 switch to user mode.
111
Rik van Riel28b2ee22008-07-23 21:27:05 -0700112config HAVE_IOREMAP_PROT
Jan Beulich9ba16082008-10-15 22:01:38 -0700113 bool
Rik van Riel28b2ee22008-07-23 21:27:05 -0700114
Mathieu Desnoyers125e5642008-02-02 15:10:36 -0500115config HAVE_KPROBES
Jan Beulich9ba16082008-10-15 22:01:38 -0700116 bool
Ananth N Mavinakayanahalli9edddaa2008-03-04 14:28:37 -0800117
118config HAVE_KRETPROBES
Jan Beulich9ba16082008-10-15 22:01:38 -0700119 bool
Arthur Kepner74bc7ce2008-04-29 01:00:30 -0700120
Masami Hiramatsuafd66252010-02-25 08:34:07 -0500121config HAVE_OPTPROBES
122 bool
Cong Wangd314d742012-03-23 15:01:51 -0700123
124config HAVE_NMI_WATCHDOG
125 bool
Roland McGrath1f5a4ad2008-07-25 19:45:57 -0700126#
127# An arch should select this if it provides all these things:
128#
129# task_pt_regs() in asm/processor.h or asm/ptrace.h
130# arch_has_single_step() if there is hardware single-step support
131# arch_has_block_step() if there is hardware block-step support
Roland McGrath1f5a4ad2008-07-25 19:45:57 -0700132# asm/syscall.h supplying asm-generic/syscall.h interface
133# linux/regset.h user_regset interfaces
134# CORE_DUMP_USE_REGSET #define'd in linux/elf.h
135# TIF_SYSCALL_TRACE calls tracehook_report_syscall_{entry,exit}
136# TIF_NOTIFY_RESUME calls tracehook_notify_resume()
137# signal delivery calls tracehook_signal_handler()
138#
139config HAVE_ARCH_TRACEHOOK
Jan Beulich9ba16082008-10-15 22:01:38 -0700140 bool
Roland McGrath1f5a4ad2008-07-25 19:45:57 -0700141
Arthur Kepner74bc7ce2008-04-29 01:00:30 -0700142config HAVE_DMA_ATTRS
Jan Beulich9ba16082008-10-15 22:01:38 -0700143 bool
Jens Axboe3d442232008-06-26 11:21:34 +0200144
Marek Szyprowski55bb0332011-12-29 13:09:51 +0100145config HAVE_DMA_CONTIGUOUS
146 bool
147
Jens Axboe3d442232008-06-26 11:21:34 +0200148config USE_GENERIC_SMP_HELPERS
Jan Beulich9ba16082008-10-15 22:01:38 -0700149 bool
David Brownell9483a572008-07-23 21:26:48 -0700150
Heiko Carstensf850c302010-02-10 17:25:17 +0100151config HAVE_REGS_AND_STACK_ACCESS_API
152 bool
Heiko Carstense01292b2010-02-18 14:25:21 +0100153 help
154 This symbol should be selected by an architecure if it supports
155 the API needed to access registers and stack entries from pt_regs,
156 declared in asm/ptrace.h
157 For example the kprobes-based event tracer needs this API.
Heiko Carstensf850c302010-02-10 17:25:17 +0100158
David Brownell9483a572008-07-23 21:26:48 -0700159config HAVE_CLK
Jan Beulich9ba16082008-10-15 22:01:38 -0700160 bool
David Brownell9483a572008-07-23 21:26:48 -0700161 help
162 The <linux/clk.h> calls support software clock gating and
163 thus are a key power management tool on many systems.
164
Joerg Roedel5ee00bd2009-01-09 12:14:24 +0100165config HAVE_DMA_API_DEBUG
166 bool
Heiko Carstens36cd3c92009-04-09 18:48:34 +0200167
K.Prasad62a038d2009-06-01 23:43:33 +0530168config HAVE_HW_BREAKPOINT
169 bool
Frederic Weisbecker99e8c5a2009-12-17 01:33:54 +0100170 depends on PERF_EVENTS
K.Prasad62a038d2009-06-01 23:43:33 +0530171
Frederic Weisbecker01027522010-04-11 18:55:56 +0200172config HAVE_MIXED_BREAKPOINTS_REGS
173 bool
174 depends on HAVE_HW_BREAKPOINT
175 help
176 Depending on the arch implementation of hardware breakpoints,
177 some of them have separate registers for data and instruction
178 breakpoints addresses, others have mixed registers to store
179 them but define the access type in a control register.
180 Select this option if your arch implements breakpoints under the
181 latter fashion.
182
Avi Kivity7c68af62009-09-19 09:40:22 +0300183config HAVE_USER_RETURN_NOTIFIER
184 bool
Ingo Molnara1922ed2009-09-07 08:19:51 +0200185
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200186config HAVE_PERF_EVENTS_NMI
187 bool
Frederic Weisbecker23637d42010-05-15 23:15:20 +0200188 help
189 System hardware can generate an NMI using the perf event
190 subsystem. Also has support for calculating CPU cycle events
191 to determine how many clock cycles in a given period.
Frederic Weisbeckerc01d4322010-05-15 22:57:48 +0200192
Jason Baronbf5438fc2010-09-17 11:09:00 -0400193config HAVE_ARCH_JUMP_LABEL
194 bool
195
Gerald Schaefer335d7af2010-11-22 15:47:36 +0100196config HAVE_ARCH_MUTEX_CPU_RELAX
197 bool
198
Peter Zijlstra26723912011-05-24 17:12:00 -0700199config HAVE_RCU_TABLE_FREE
200 bool
201
Huang Yingdf013ff2011-07-13 13:14:22 +0800202config ARCH_HAVE_NMI_SAFE_CMPXCHG
203 bool
204
Heiko Carstens43570fd2012-01-12 17:17:27 -0800205config HAVE_ALIGNED_STRUCT_PAGE
206 bool
207 help
208 This makes sure that struct pages are double word aligned and that
209 e.g. the SLUB allocator can perform double word atomic operations
210 on a struct page for better performance. However selecting this
211 might increase the size of a struct page by a word.
212
Heiko Carstens41561532012-01-12 17:17:30 -0800213config HAVE_CMPXCHG_LOCAL
214 bool
215
Heiko Carstens25654092012-01-12 17:17:33 -0800216config HAVE_CMPXCHG_DOUBLE
217 bool
218
Chris Metcalf48b25c42012-03-15 13:13:38 -0400219config ARCH_WANT_OLD_COMPAT_IPC
220 bool
221
Peter Oberparleiter2521f2c2009-06-17 16:28:08 -0700222source "kernel/gcov/Kconfig"