select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
select ARCH_HAS_FAST_MULTIPLIER
+ select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_MIGHT_HAVE_PC_PARPORT
select ARCH_MIGHT_HAVE_PC_SERIO
select HAVE_AOUT if X86_32
def_bool y
depends on KPROBES || PERF_EVENTS || UPROBES
+ config PERF_EVENTS_INTEL_UNCORE
+ def_bool y
+ depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
+
config OUTPUT_FORMAT
string
default "elf32-i386" if X86_32
config SCHED_OMIT_FRAME_POINTER
def_bool y
- prompt "Single-depth WCHAN output"
+ prompt "Single-depth WCHAN output" if !LTO && !FRAME_POINTER
depends on X86
---help---
Calculate simpler /proc/<PID>/wchan values. If this option
config X86_LOCAL_APIC
def_bool y
depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
+ select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
config X86_IO_APIC
- def_bool y
- depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
- select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
+ def_bool X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
+ depends on X86_LOCAL_APIC
select IRQ_DOMAIN
config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
def_bool y
depends on X86_16BIT && X86_64
+ config X86_VSYSCALL_EMULATION
+ bool "Enable vsyscall emulation" if EXPERT
+ default y
+ depends on X86_64
+ ---help---
+ This enables emulation of the legacy vsyscall page. Disabling
+ it is roughly equivalent to booting with vsyscall=none, except
+ that it will also disable the helpful warning if a program
+ tries to use a vsyscall. With this option set to N, offending
+ programs will just segfault, citing addresses of the form
+ 0xffffffffff600?00.
+
+ This option is required by many programs built before 2013, and
+ care should be used even with newer programs if set to N.
+
+ Disabling this option saves about 7K of kernel size and
+ possibly 4K of additional runtime pagetable memory.
+
config TOSHIBA
tristate "Toshiba Laptop support"
depends on X86_32
If unsure, say Y.
+ config X86_INTEL_MPX
+ prompt "Intel MPX (Memory Protection Extensions)"
+ def_bool n
+ depends on CPU_SUP_INTEL
+ ---help---
+ MPX provides hardware features that can be used in
+ conjunction with compiler-instrumented code to check
+ memory references. It is designed to detect buffer
+ overflow or underflow bugs.
+
+ This option enables running applications which are
+ instrumented or otherwise use MPX. It does not use MPX
+ itself inside the kernel or to protect the kernel
+ against bad memory references.
+
+ Enabling this option will make the kernel larger:
+ ~8k of kernel text and 36 bytes of data on a 64-bit
+ defconfig. It adds a long to the 'mm_struct' which
+ will increase the kernel memory overhead of each
+ process and adds some branches to paths used during
+ exec() and munmap().
+
+ For details, see Documentation/x86/intel_mpx.txt
+
+ If unsure, say N.
+
config EFI
bool "EFI runtime service support"
depends on ACPI
thousands of CPUs. It also scales down nicely to
smaller systems.
- config TREE_PREEMPT_RCU
+ config PREEMPT_RCU
bool "Preemptible tree-based hierarchical RCU"
depends on PREEMPT
select IRQ_WORK
endchoice
- config PREEMPT_RCU
- def_bool TREE_PREEMPT_RCU
- help
- This option enables preemptible-RCU code that is common between
- TREE_PREEMPT_RCU and, in the old days, TINY_PREEMPT_RCU.
-
config TASKS_RCU
bool "Task_based RCU implementation using voluntary context switch"
default n
If unsure, say N.
config RCU_STALL_COMMON
- def_bool ( TREE_RCU || TREE_PREEMPT_RCU || RCU_TRACE )
+ def_bool ( TREE_RCU || PREEMPT_RCU || RCU_TRACE )
help
This option enables RCU CPU stall code that is common between
the TINY and TREE variants of RCU. The purpose is to allow
int "Tree-based hierarchical RCU fanout value"
range 2 64 if 64BIT
range 2 32 if !64BIT
- depends on TREE_RCU || TREE_PREEMPT_RCU
+ depends on TREE_RCU || PREEMPT_RCU
default 64 if 64BIT
default 32 if !64BIT
help
int "Tree-based hierarchical RCU leaf-level fanout value"
range 2 RCU_FANOUT if 64BIT
range 2 RCU_FANOUT if !64BIT
- depends on TREE_RCU || TREE_PREEMPT_RCU
+ depends on TREE_RCU || PREEMPT_RCU
default 16
help
This option controls the leaf-level fanout of hierarchical
config RCU_FANOUT_EXACT
bool "Disable tree-based hierarchical RCU auto-balancing"
- depends on TREE_RCU || TREE_PREEMPT_RCU
+ depends on TREE_RCU || PREEMPT_RCU
default n
help
This option forces use of the exact RCU_FANOUT value specified,
Say N if you are unsure.
config TREE_RCU_TRACE
- def_bool RCU_TRACE && ( TREE_RCU || TREE_PREEMPT_RCU )
+ def_bool RCU_TRACE && ( TREE_RCU || PREEMPT_RCU )
select DEBUG_FS
help
This option provides tracing for the TREE_RCU and
- TREE_PREEMPT_RCU implementations, permitting Makefile to
+ PREEMPT_RCU implementations, permitting Makefile to
trivially select kernel/rcutree_trace.c.
config RCU_BOOST
Say Y here if you are working with real-time apps or heavy loads
Say N here if you are unsure.
- config RCU_BOOST_PRIO
- int "Real-time priority to boost RCU readers to"
+ config RCU_KTHREAD_PRIO
+ int "Real-time priority to use for RCU worker threads"
range 1 99
depends on RCU_BOOST
default 1
help
- This option specifies the real-time priority to which long-term
- preempted RCU readers are to be boosted. If you are working
- with a real-time application that has one or more CPU-bound
- threads running at a real-time priority level, you should set
- RCU_BOOST_PRIO to a priority higher then the highest-priority
- real-time CPU-bound thread. The default RCU_BOOST_PRIO value
- of 1 is appropriate in the common case, which is real-time
+ This option specifies the SCHED_FIFO priority value that will be
+ assigned to the rcuc/n and rcub/n threads and is also the value
+ used for RCU_BOOST (if enabled). If you are working with a
+ real-time application that has one or more CPU-bound threads
+ running at a real-time priority level, you should set
+ RCU_KTHREAD_PRIO to a priority higher than the highest-priority
+ real-time CPU-bound application thread. The default RCU_KTHREAD_PRIO
+ value of 1 is appropriate in the common case, which is real-time
applications that do not have any CPU-bound threads.
Some real-time applications might not have a single real-time
thread that saturates a given CPU, but instead might have
multiple real-time threads that, taken together, fully utilize
- that CPU. In this case, you should set RCU_BOOST_PRIO to
+ that CPU. In this case, you should set RCU_KTHREAD_PRIO to
a priority higher than the lowest-priority thread that is
conspiring to prevent the CPU from running any non-real-time
tasks. For example, if one thread at priority 10 and another
thread at priority 5 are between themselves fully consuming
- the CPU time on a given CPU, then RCU_BOOST_PRIO should be
+ the CPU time on a given CPU, then RCU_KTHREAD_PRIO should be
set to priority 6 or higher.
Specify the real-time priority, or take the default if unsure.
config RCU_NOCB_CPU
bool "Offload RCU callback processing from boot-selected CPUs"
- depends on TREE_RCU || TREE_PREEMPT_RCU
+ depends on TREE_RCU || PREEMPT_RCU
default n
help
Use this option to reduce OS jitter for aggressive HPC or
choice
prompt "Build-forced no-CBs CPUs"
default RCU_NOCB_CPU_NONE
+ depends on RCU_NOCB_CPU
help
This option allows no-CBs CPUs (whose RCU callbacks are invoked
from kthreads rather than from softirq context) to be specified
config RCU_NOCB_CPU_NONE
bool "No build_forced no-CBs CPUs"
- depends on RCU_NOCB_CPU
help
This option does not force any of the CPUs to be no-CBs CPUs.
Only CPUs designated by the rcu_nocbs= boot parameter will be
config RCU_NOCB_CPU_ZERO
bool "CPU 0 is a build_forced no-CBs CPU"
- depends on RCU_NOCB_CPU
help
This option forces CPU 0 to be a no-CBs CPU, so that its RCU
callbacks are invoked by a per-CPU kthread whose name begins
config RCU_NOCB_CPU_ALL
bool "All CPUs are build_forced no-CBs CPUs"
- depends on RCU_NOCB_CPU
help
This option forces all CPUs to be no-CBs CPUs. The rcu_nocbs=
boot parameter will be ignored. All CPUs' RCU callbacks will
config ARCH_WANT_NUMA_VARIABLE_LOCALITY
bool
- config NUMA_BALANCING_DEFAULT_ENABLED
- bool "Automatically enable NUMA aware memory/task placement"
- default y
- depends on NUMA_BALANCING
- help
- If set, automatic NUMA balancing will be enabled if running on a NUMA
- machine.
-
config NUMA_BALANCING
bool "Memory placement aware NUMA scheduler"
depends on ARCH_SUPPORTS_NUMA_BALANCING
This system will be inactive on UMA systems.
+ config NUMA_BALANCING_DEFAULT_ENABLED
+ bool "Automatically enable NUMA aware memory/task placement"
+ default y
+ depends on NUMA_BALANCING
+ help
+ If set, automatic NUMA balancing will be enabled if running on a NUMA
+ machine.
+
menuconfig CGROUPS
boolean "Control Group support"
select KERNFS
Provides a simple Resource Controller for monitoring the
total CPU consumed by the tasks in a cgroup.
- config RESOURCE_COUNTERS
- bool "Resource counters"
- help
- This option enables controller independent resource accounting
- infrastructure that works with cgroups.
+ config PAGE_COUNTER
+ bool
config MEMCG
bool "Memory Resource Controller for Control Groups"
- depends on RESOURCE_COUNTERS
+ select PAGE_COUNTER
select EVENTFD
help
Provides a memory resource controller that manages both anonymous
memory and page cache. (See Documentation/cgroups/memory.txt)
- Note that setting this option increases fixed memory overhead
- associated with each page of memory in the system. By this,
- 8(16)bytes/PAGE_SIZE on 32(64)bit system will be occupied by memory
- usage tracking struct at boot. Total amount of this is printed out
- at boot.
-
- Only enable when you're ok with these trade offs and really
- sure you need the memory resource controller. Even when you enable
- this, you can set "cgroup_disable=memory" at your boot option to
- disable memory resource controller and you can avoid overheads.
- (and lose benefits of memory resource controller)
-
config MEMCG_SWAP
bool "Memory Resource Controller Swap Extension"
depends on MEMCG && SWAP
config CGROUP_HUGETLB
bool "HugeTLB Resource Controller for Control Groups"
- depends on RESOURCE_COUNTERS && HUGETLB_PAGE
+ depends on HUGETLB_PAGE
+ select PAGE_COUNTER
default n
help
Provides a cgroup Resource Controller for HugeTLB pages.
endif
+ config INIT_FALLBACK
+ bool "Fall back to defaults if init= parameter is bad"
+ default y
+ help
+ If enabled, the kernel will try the default init binaries if an
+ explicit request from the init= parameter fails.
+
+ This can have unexpected effects. For example, booting
+ with init=/sbin/kiosk_app will run /sbin/init or even /bin/sh
+ if /sbin/kiosk_app cannot be executed.
+
+ The default value of Y is consistent with historical behavior.
+ Selecting N is likely to be more appropriate for most uses,
+ especially on kiosks and on kernels that are intended to be
+ run under the control of a script.
+
config CC_OPTIMIZE_FOR_SIZE
bool "Optimize for size"
help
If unsure, say N.
+config LTO_MENU
+ bool "Enable gcc link time optimization (LTO)"
+ # Only tested on X86 for now. For other architectures you likely
+ # have to fix some things first, like adding asmlinkages etc.
+ depends on X86
+ # lto does not support excluding flags for specific files
+ # right now. Can be removed if that is fixed.
+ depends on !FUNCTION_TRACER
+ help
+ With this option gcc will do whole program optimizations for
+ the whole kernel and module. This increases compile time, but can
+ lead to better code. It allows gcc to inline functions between
+ different files and do other optimization. It might also trigger
+ bugs due to more aggressive optimization. It allows gcc to drop unused
+ code. On smaller monolithic kernel configurations
+ it usually leads to smaller kernels, especially when modules
+ are disabled.
+
+ With this option gcc will also do some global checking over
+ different source files. It also disables a number of kernel
+ features.
+
+ This option is recommended for release builds. With LTO
+ the kernel always has to be re-optimized (but not re-parsed)
+ on each build.
+
+ This requires a gcc 4.8 or later compiler and
+ Linux binutils 2.21.51.0.3 or later. gcc 4.9 builds significantly
+ faster than 4.8 It does not currently work with a FSF release of
+ binutils or with the gold linker.
+
+ On larger configurations this may need more than 4GB of RAM.
+ It will likely not work on those with a 32bit compiler.
+
+ When the toolchain support is not available this will (hopefully)
+ be automatically disabled.
+
+ For more information see Documentation/lto-build
+
+config LTO_DISABLE
+ bool "Disable LTO again"
+ depends on LTO_MENU
+ default n
+ help
+ This option is merely here so that allyesconfig or allmodconfig do
+ not enable LTO. If you want to actually use LTO do not enable.
+
+config LTO
+ bool
+ default y
+ depends on LTO_MENU && !LTO_DISABLE
+
+config LTO_DEBUG
+ bool "Enable LTO compile time debugging"
+ depends on LTO
+ help
+ Enable LTO debugging in the compiler. The compiler dumps
+ some log files that make it easier to figure out LTO
+ behavior. The log files also allow to reconstruct
+ the global inlining and a global callgraph.
+ They however add some (single threaded) cost to the
+ compilation. When in doubt do not enable.
+
+config LTO_CP_CLONE
+ bool "Allow aggressive cloning for function specialization"
+ depends on LTO
+ help
+ Allow the compiler to clone and specialize functions for specific
+ arguments when it determines these arguments are very commonly
+ called. Experimential. Will increase text size.
+
config SYSCTL
bool
config HAVE_PCSPKR_PLATFORM
bool
+ # interpreter that classic socket filters depend on
+ config BPF
+ bool
+
menuconfig EXPERT
bool "Configure standard kernel features (expert users)"
# Unhide debug options, to make the on-by-default options visible
If unsure, say Y.
+ # syscall, maps, verifier
+ config BPF_SYSCALL
+ bool "Enable bpf() system call" if EXPERT
+ select ANON_INODES
+ select BPF
+ default n
+ help
+ Enable the bpf() system call that allows to manipulate eBPF
+ programs and maps via file descriptors.
+
config SHMEM
bool "Use full shmem filesystem" if EXPERT
default y
config MODVERSIONS
bool "Module versioning support"
+ # LTO should work with gcc 4.9
+ depends on !LTO
help
Usually, you have to use modules compiled with your kernel.
Saying Y here makes it sometimes possible to use modules
projects / karo-tx-linux.git / commitdiff