[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / Kconfig

#
# General architecture dependent options
#

config OPROFILE
	tristate "OProfile system profiling"
	depends on PROFILING
	depends on HAVE_OPROFILE
	select RING_BUFFER
	select RING_BUFFER_ALLOW_SWAP
	help
	  OProfile is a profiling system capable of profiling the
	  whole system, include the kernel, kernel modules, libraries,
	  and applications.

	  If unsure, say N.

config OPROFILE_EVENT_MULTIPLEX
	bool "OProfile multiplexing support (EXPERIMENTAL)"
	default n
	depends on OPROFILE && X86
	help
	  The number of hardware counters is limited. The multiplexing
	  feature enables OProfile to gather more events than counters
	  are provided by the hardware. This is realized by switching
	  between events at an user specified time interval.

	  If unsure, say N.

config HAVE_OPROFILE
	bool

config OPROFILE_NMI_TIMER
	def_bool y
	depends on PERF_EVENTS && HAVE_PERF_EVENTS_NMI

config KPROBES
	bool "Kprobes"
	depends on MODULES
	depends on HAVE_KPROBES
	select KALLSYMS
	help
	  Kprobes allows you to trap at almost any kernel address and
	  execute a callback function.  register_kprobe() establishes
	  a probepoint and specifies the callback.  Kprobes is useful
	  for kernel debugging, non-intrusive instrumentation and testing.
	  If in doubt, say "N".

config JUMP_LABEL
       bool "Optimize very unlikely/likely branches"
       depends on HAVE_ARCH_JUMP_LABEL
       help
         This option enables a transparent branch optimization that
	 makes certain almost-always-true or almost-always-false branch
	 conditions even cheaper to execute within the kernel.

	 Certain performance-sensitive kernel code, such as trace points,
	 scheduler functionality, networking code and KVM have such
	 branches and include support for this optimization technique.

         If it is detected that the compiler has support for "asm goto",
	 the kernel will compile such branches with just a nop
	 instruction. When the condition flag is toggled to true, the
	 nop will be converted to a jump instruction to execute the
	 conditional block of instructions.

	 This technique lowers overhead and stress on the branch prediction
	 of the processor and generally makes the kernel faster. The update
	 of the condition is slower, but those are always very rare.

	 ( On 32-bit x86, the necessary options added to the compiler
	   flags may increase the size of the kernel slightly. )

config OPTPROBES
	def_bool y
	depends on KPROBES && HAVE_OPTPROBES
	depends on !PREEMPT

config UPROBES
	bool "Transparent user-space probes (EXPERIMENTAL)"
	depends on UPROBE_EVENT && PERF_EVENTS
	default n
	help
	  Uprobes is the user-space counterpart to kprobes: they
	  enable instrumentation applications (such as 'perf probe')
	  to establish unintrusive probes in user-space binaries and
	  libraries, by executing handler functions when the probes
	  are hit by user-space applications.

	  ( These probes come in the form of single-byte breakpoints,
	    managed by the kernel and kept transparent to the probed
	    application. )

	  If in doubt, say "N".

config HAVE_EFFICIENT_UNALIGNED_ACCESS
	bool
	help
	  Some architectures are unable to perform unaligned accesses
	  without the use of get_unaligned/put_unaligned. Others are
	  unable to perform such accesses efficiently (e.g. trap on
	  unaligned access and require fixing it up in the exception
	  handler.)

	  This symbol should be selected by an architecture if it can
	  perform unaligned accesses efficiently to allow different
	  code paths to be selected for these cases. Some network
	  drivers, for example, could opt to not fix up alignment
	  problems with received packets if doing so would not help
	  much.

	  See Documentation/unaligned-memory-access.txt for more
	  information on the topic of unaligned memory accesses.

config HAVE_SYSCALL_WRAPPERS
	bool

config KRETPROBES
	def_bool y
	depends on KPROBES && HAVE_KRETPROBES

config USER_RETURN_NOTIFIER
	bool
	depends on HAVE_USER_RETURN_NOTIFIER
	help
	  Provide a kernel-internal notification when a cpu is about to
	  switch to user mode.

config HAVE_IOREMAP_PROT
	bool

config HAVE_KPROBES
	bool

config HAVE_KRETPROBES
	bool

config HAVE_OPTPROBES
	bool

config HAVE_NMI_WATCHDOG
	bool
#
# An arch should select this if it provides all these things:
#
#	task_pt_regs()		in asm/processor.h or asm/ptrace.h
#	arch_has_single_step()	if there is hardware single-step support
#	arch_has_block_step()	if there is hardware block-step support
#	asm/syscall.h		supplying asm-generic/syscall.h interface
#	linux/regset.h		user_regset interfaces
#	CORE_DUMP_USE_REGSET	#define'd in linux/elf.h
#	TIF_SYSCALL_TRACE	calls tracehook_report_syscall_{entry,exit}
#	TIF_NOTIFY_RESUME	calls tracehook_notify_resume()
#	signal delivery		calls tracehook_signal_handler()
#
config HAVE_ARCH_TRACEHOOK
	bool

config HAVE_DMA_ATTRS
	bool

config HAVE_DMA_CONTIGUOUS
	bool

config USE_GENERIC_SMP_HELPERS
	bool

config GENERIC_SMP_IDLE_THREAD
       bool

# Select if arch init_task initializer is different to init/init_task.c
config ARCH_INIT_TASK
       bool

# Select if arch has its private alloc_task_struct() function
config ARCH_TASK_STRUCT_ALLOCATOR
	bool

# Select if arch has its private alloc_thread_info() function
config ARCH_THREAD_INFO_ALLOCATOR
	bool

config HAVE_REGS_AND_STACK_ACCESS_API
	bool
	help
	  This symbol should be selected by an architecure if it supports
	  the API needed to access registers and stack entries from pt_regs,
	  declared in asm/ptrace.h
	  For example the kprobes-based event tracer needs this API.

config HAVE_CLK
	bool
	help
	  The <linux/clk.h> calls support software clock gating and
	  thus are a key power management tool on many systems.

config HAVE_DMA_API_DEBUG
	bool

config HAVE_HW_BREAKPOINT
	bool
	depends on PERF_EVENTS

config HAVE_MIXED_BREAKPOINTS_REGS
	bool
	depends on HAVE_HW_BREAKPOINT
	help
	  Depending on the arch implementation of hardware breakpoints,
	  some of them have separate registers for data and instruction
	  breakpoints addresses, others have mixed registers to store
	  them but define the access type in a control register.
	  Select this option if your arch implements breakpoints under the
	  latter fashion.

config HAVE_USER_RETURN_NOTIFIER
	bool

config HAVE_PERF_EVENTS_NMI
	bool
	help
	  System hardware can generate an NMI using the perf event
	  subsystem.  Also has support for calculating CPU cycle events
	  to determine how many clock cycles in a given period.

config HAVE_PERF_REGS
	bool
	help
	  Support selective register dumps for perf events. This includes
	  bit-mapping of each registers and a unique architecture id.

config HAVE_PERF_USER_STACK_DUMP
	bool
	help
	  Support user stack dumps for perf event samples. This needs
	  access to the user stack pointer which is not unified across
	  architectures.

config HAVE_ARCH_JUMP_LABEL
	bool

config HAVE_ARCH_MUTEX_CPU_RELAX
	bool

config HAVE_RCU_TABLE_FREE
	bool

config ARCH_HAVE_NMI_SAFE_CMPXCHG
	bool

config HAVE_ALIGNED_STRUCT_PAGE
	bool
	help
	  This makes sure that struct pages are double word aligned and that
	  e.g. the SLUB allocator can perform double word atomic operations
	  on a struct page for better performance. However selecting this
	  might increase the size of a struct page by a word.

config HAVE_CMPXCHG_LOCAL
	bool

config HAVE_CMPXCHG_DOUBLE
	bool

config ARCH_WANT_IPC_PARSE_VERSION
	bool

config ARCH_WANT_COMPAT_IPC_PARSE_VERSION
	bool

config ARCH_WANT_OLD_COMPAT_IPC
	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
	bool

config GENERIC_KERNEL_THREAD
	bool

config GENERIC_KERNEL_EXECVE
	bool

config HAVE_ARCH_SECCOMP_FILTER
	bool
	help
	  An arch should select this symbol if it provides all of these things:
	  - syscall_get_arch()
	  - syscall_get_arguments()
	  - syscall_rollback()
	  - syscall_set_return_value()
	  - SIGSYS siginfo_t support
	  - secure_computing is called from a ptrace_event()-safe context
	  - secure_computing return value is checked and a return value of -1
	    results in the system call being skipped immediately.

config SECCOMP_FILTER
	def_bool y
	depends on HAVE_ARCH_SECCOMP_FILTER && SECCOMP && NET
	help
	  Enable tasks to build secure computing environments defined
	  in terms of Berkeley Packet Filter programs which implement
	  task-defined system call filtering polices.

	  See Documentation/prctl/seccomp_filter.txt for details.

config HAVE_CONTEXT_TRACKING
	bool
	help
	  Provide kernel/user boundaries probes necessary for subsystems
	  that need it, such as userspace RCU extended quiescent state.
	  Syscalls need to be wrapped inside user_exit()-user_enter() through
	  the slow path using TIF_NOHZ flag. Exceptions handlers must be
	  wrapped as well. Irqs are already protected inside
	  rcu_irq_enter/rcu_irq_exit() but preemption or signal handling on
	  irq exit still need to be protected.

config HAVE_VIRT_CPU_ACCOUNTING
	bool

config HAVE_IRQ_TIME_ACCOUNTING
	bool
	help
	  Archs need to ensure they use a high enough resolution clock to
	  support irq time accounting and then call enable_sched_clock_irqtime().

config HAVE_ARCH_TRANSPARENT_HUGEPAGE
	bool

config HAVE_MOD_ARCH_SPECIFIC
	bool
	help
	  The arch uses struct mod_arch_specific to store data.  Many arches
	  just need a simple module loader without arch specific data - those
	  should not enable this.

config MODULES_USE_ELF_RELA
	bool
	help
	  Modules only use ELF RELA relocations.  Modules with ELF REL
	  relocations will give an error.

config MODULES_USE_ELF_REL
	bool
	help
	  Modules only use ELF REL relocations.  Modules with ELF RELA
	  relocations will give an error.

#
# ABI hall of shame
#
config CLONE_BACKWARDS
	bool
	help
	  Architecture has tls passed as the 4th argument of clone(2),
	  not the 5th one.

config CLONE_BACKWARDS2
	bool
	help
	  Architecture has the first two arguments of clone(2) swapped.

source "kernel/gcov/Kconfig"
Commit	Line	Data
	1	#
	2	# General architecture dependent options
	3	#
	4
	5	config OPROFILE
	6	tristate "OProfile system profiling"
	7	depends on PROFILING
	8	depends on HAVE_OPROFILE
	9	select RING_BUFFER
	10	select RING_BUFFER_ALLOW_SWAP
	11	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
	18	config 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
	30	config HAVE_OPROFILE
	31	bool
	32
	33	config OPROFILE_NMI_TIMER
	34	def_bool y
	35	depends on PERF_EVENTS && HAVE_PERF_EVENTS_NMI
	36
	37	config KPROBES
	38	bool "Kprobes"
	39	depends on MODULES
	40	depends on HAVE_KPROBES
	41	select KALLSYMS
	42	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
	49	config JUMP_LABEL
	50	bool "Optimize very unlikely/likely branches"
	51	depends on HAVE_ARCH_JUMP_LABEL
	52	help
	53	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.
	56
	57	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. )
	73
	74	config OPTPROBES
	75	def_bool y
	76	depends on KPROBES && HAVE_OPTPROBES
	77	depends on !PREEMPT
	78
	79	config UPROBES
	80	bool "Transparent user-space probes (EXPERIMENTAL)"
	81	depends on UPROBE_EVENT && PERF_EVENTS
	82	default n
	83	help
	84	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. )
	93
	94	If in doubt, say "N".
	95
	96	config HAVE_EFFICIENT_UNALIGNED_ACCESS
	97	bool
	98	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
	115	config HAVE_SYSCALL_WRAPPERS
	116	bool
	117
	118	config KRETPROBES
	119	def_bool y
	120	depends on KPROBES && HAVE_KRETPROBES
	121
	122	config 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
	129	config HAVE_IOREMAP_PROT
	130	bool
	131
	132	config HAVE_KPROBES
	133	bool
	134
	135	config HAVE_KRETPROBES
	136	bool
	137
	138	config HAVE_OPTPROBES
	139	bool
	140
	141	config HAVE_NMI_WATCHDOG
	142	bool
	143	#
	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
	149	# 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	#
	156	config HAVE_ARCH_TRACEHOOK
	157	bool
	158
	159	config HAVE_DMA_ATTRS
	160	bool
	161
	162	config HAVE_DMA_CONTIGUOUS
	163	bool
	164
	165	config USE_GENERIC_SMP_HELPERS
	166	bool
	167
	168	config GENERIC_SMP_IDLE_THREAD
	169	bool
	170
	171	# Select if arch init_task initializer is different to init/init_task.c
	172	config ARCH_INIT_TASK
	173	bool
	174
	175	# Select if arch has its private alloc_task_struct() function
	176	config ARCH_TASK_STRUCT_ALLOCATOR
	177	bool
	178
	179	# Select if arch has its private alloc_thread_info() function
	180	config ARCH_THREAD_INFO_ALLOCATOR
	181	bool
	182
	183	config HAVE_REGS_AND_STACK_ACCESS_API
	184	bool
	185	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.
	190
	191	config HAVE_CLK
	192	bool
	193	help
	194	The <linux/clk.h> calls support software clock gating and
	195	thus are a key power management tool on many systems.
	196
	197	config HAVE_DMA_API_DEBUG
	198	bool
	199
	200	config HAVE_HW_BREAKPOINT
	201	bool
	202	depends on PERF_EVENTS
	203
	204	config 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
	215	config HAVE_USER_RETURN_NOTIFIER
	216	bool
	217
	218	config HAVE_PERF_EVENTS_NMI
	219	bool
	220	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.
	224
	225	config 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
	231	config 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
	238	config HAVE_ARCH_JUMP_LABEL
	239	bool
	240
	241	config HAVE_ARCH_MUTEX_CPU_RELAX
	242	bool
	243
	244	config HAVE_RCU_TABLE_FREE
	245	bool
	246
	247	config ARCH_HAVE_NMI_SAFE_CMPXCHG
	248	bool
	249
	250	config 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
	258	config HAVE_CMPXCHG_LOCAL
	259	bool
	260
	261	config HAVE_CMPXCHG_DOUBLE
	262	bool
	263
	264	config ARCH_WANT_IPC_PARSE_VERSION
	265	bool
	266
	267	config ARCH_WANT_COMPAT_IPC_PARSE_VERSION
	268	bool
	269
	270	config ARCH_WANT_OLD_COMPAT_IPC
	271	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
	272	bool
	273
	274	config GENERIC_KERNEL_THREAD
	275	bool
	276
	277	config GENERIC_KERNEL_EXECVE
	278	bool
	279
	280	config HAVE_ARCH_SECCOMP_FILTER
	281	bool
	282	help
	283	An arch should select this symbol if it provides all of these things:
	284	- syscall_get_arch()
	285	- syscall_get_arguments()
	286	- syscall_rollback()
	287	- syscall_set_return_value()
	288	- 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.
	292
	293	config 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
	303	config HAVE_CONTEXT_TRACKING
	304	bool
	305	help
	306	Provide kernel/user boundaries probes necessary for subsystems
	307	that need it, such as userspace RCU extended quiescent state.
	308	Syscalls need to be wrapped inside user_exit()-user_enter() through
	309	the slow path using TIF_NOHZ flag. Exceptions handlers must be
	310	wrapped as well. Irqs are already protected inside
	311	rcu_irq_enter/rcu_irq_exit() but preemption or signal handling on
	312	irq exit still need to be protected.
	313
	314	config HAVE_VIRT_CPU_ACCOUNTING
	315	bool
	316
	317	config HAVE_IRQ_TIME_ACCOUNTING
	318	bool
	319	help
	320	Archs need to ensure they use a high enough resolution clock to
	321	support irq time accounting and then call enable_sched_clock_irqtime().
	322
	323	config HAVE_ARCH_TRANSPARENT_HUGEPAGE
	324	bool
	325
	326	config HAVE_MOD_ARCH_SPECIFIC
	327	bool
	328	help
	329	The arch uses struct mod_arch_specific to store data. Many arches
	330	just need a simple module loader without arch specific data - those
	331	should not enable this.
	332
	333	config MODULES_USE_ELF_RELA
	334	bool
	335	help
	336	Modules only use ELF RELA relocations. Modules with ELF REL
	337	relocations will give an error.
	338
	339	config MODULES_USE_ELF_REL
	340	bool
	341	help
	342	Modules only use ELF REL relocations. Modules with ELF RELA
	343	relocations will give an error.
	344
	345	#
	346	# ABI hall of shame
	347	#
	348	config CLONE_BACKWARDS
	349	bool
	350	help
	351	Architecture has tls passed as the 4th argument of clone(2),
	352	not the 5th one.
	353
	354	config CLONE_BACKWARDS2
	355	bool
	356	help
	357	Architecture has the first two arguments of clone(2) swapped.
	358
	359	source "kernel/gcov/Kconfig"