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 KALLSYMS && MODULES
+ 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
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 KPROBES_ON_FTRACE
+ def_bool y
+ depends on KPROBES && HAVE_KPROBES_ON_FTRACE
+ depends on DYNAMIC_FTRACE_WITH_REGS
+ help
+ If function tracer is enabled and the arch supports full
+ passing of pt_regs to function tracing, then kprobes can
+ optimize on top of function tracing.
+
+config UPROBES
+ bool "Transparent user-space probes (EXPERIMENTAL)"
+ depends on UPROBE_EVENT && PERF_EVENTS
+ default n
+ select PERCPU_RWSEM
+ 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_64BIT_ALIGNED_ACCESS
+ def_bool 64BIT && !HAVE_EFFICIENT_UNALIGNED_ACCESS
+ help
+ Some architectures require 64 bit accesses to be 64 bit
+ aligned, which also requires structs containing 64 bit values
+ to be 64 bit aligned too. This includes some 32 bit
+ architectures which can do 64 bit accesses, as well as 64 bit
+ architectures without unaligned access.
+
+ This symbol should be selected by an architecture if 64 bit
+ accesses are required to be 64 bit aligned in this way even
+ though it is not a 64 bit architecture.
+
+ See Documentation/unaligned-memory-access.txt for more
+ information on the topic of unaligned memory accesses.
+
config HAVE_EFFICIENT_UNALIGNED_ACCESS
bool
help
See Documentation/unaligned-memory-access.txt for more
information on the topic of unaligned memory accesses.
-config HAVE_SYSCALL_WRAPPERS
- bool
+config ARCH_USE_BUILTIN_BSWAP
+ bool
+ help
+ Modern versions of GCC (since 4.4) have builtin functions
+ for handling byte-swapping. Using these, instead of the old
+ inline assembler that the architecture code provides in the
+ __arch_bswapXX() macros, allows the compiler to see what's
+ happening and offers more opportunity for optimisation. In
+ particular, the compiler will be able to combine the byteswap
+ with a nearby load or store and use load-and-swap or
+ store-and-swap instructions if the architecture has them. It
+ should almost *never* result in code which is worse than the
+ hand-coded assembler in <asm/swab.h>. But just in case it
+ does, the use of the builtins is optional.
+
+ Any architecture with load-and-swap or store-and-swap
+ instructions should set this. And it shouldn't hurt to set it
+ on architectures that don't have such instructions.
config KRETPROBES
def_bool y
config HAVE_KRETPROBES
bool
+config HAVE_OPTPROBES
+ bool
+
+config HAVE_KPROBES_ON_FTRACE
+ bool
+
+config HAVE_NMI_WATCHDOG
+ bool
#
# An arch should select this if it provides all these things:
#
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
config HAVE_DMA_API_DEBUG
bool
-config HAVE_DEFAULT_NO_SPIN_MUTEXES
- 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 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.
+
+config HAVE_UNDERSCORE_SYMBOL_PREFIX
+ bool
+ help
+ Some architectures generate an _ in front of C symbols; things like
+ module loading and assembly files need to know about this.
+
+#
+# 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.
+
+config ODD_RT_SIGACTION
+ bool
+ help
+ Architecture has unusual rt_sigaction(2) arguments
+
+config OLD_SIGSUSPEND
+ bool
+ help
+ Architecture has old sigsuspend(2) syscall, of one-argument variety
+
+config OLD_SIGSUSPEND3
+ bool
+ help
+ Even weirder antique ABI - three-argument sigsuspend(2)
+
+config OLD_SIGACTION
+ bool
+ help
+ Architecture has old sigaction(2) syscall. Nope, not the same
+ as OLD_SIGSUSPEND | OLD_SIGSUSPEND3 - alpha has sigsuspend(2),
+ but fairly different variant of sigaction(2), thanks to OSF/1
+ compatibility...
+
+config COMPAT_OLD_SIGACTION
+ bool
+
source "kernel/gcov/Kconfig"