mainmenu "Nautilus AeroKernel Configuration"

menu "Platform"

choice

prompt "Target Selection"

default X86_64_HOST

config X86_64_HOST

bool "x86_64 Host (including Intel Xeon Phi KNL)"

config XEON_PHI

bool "Intel Xeon Phi Accelerator (KNC)"

config HVM_HRT

bool "Hybrid Runtime AeroKernel (HRT for HVM/Multiverse)"

config GEM5

bool "GEM5-compatible x86_64 kernel"

config GEM5_FORCE_APIC_TIMER_CALIBRATION

depends on GEM5

bool "Force APIC timer calibration"

help

Skip detection of APIC bus frequency, and CPU cycles

per tick and simply set them to desired values. Note

that Gem5 gets timers right, but given how slow it is,

it can feel ridiculous in real-time, especially

when used interactively.

DO NOT SET THIS IF YOU WANT ACCURATE SIMULATED TIME

config GEM5_APIC_BUS_FREQ_HZ

depends on GEM5_FORCE_APIC_TIMER_CALIBRATION

default 10000

int "APIC bus frequency (HZ)"

help

Desired APIC bus frequency

The smaller this number is, the more frequent timer interrupts will be.

If it is too small, you'll be in an interrupt storm.

config GEM5_APIC_CYCLES_PER_US

depends on GEM5_FORCE_APIC_TIMER_CALIBRATION

default 10

int "CPU cycles per microsecond"

help

The smaller this number is, the more frequent timer interrupts will be.

If it is too small, you'll be in an interrupt storm.

endchoice

config MAX_CPUS

int "Maximum Number of CPUs"

range 1 2048

default "256"

help

Specifies the maximum number of hardware CPUs supported by Nautilus

For uniprocessor environments, set this to 1

config MAX_IOAPICS

int "Maximum Number of IOAPICS"

range 1 255

default "16"

help

Specifies the maximum number of IOAPICS supported by Nautilus

config HRT_HIHALF_OFFSET

hex "HRT High-half offset"

default 0xffff800000000000

depends on HVM_HRT

help

Sets the fixed virtual-to-physical address mapping for the HRT

config HRT_GPA_MAP_REQ

hex "HRT Max GPA to map"

default 0x200000000

depends on HVM_HRT

help

Sets the default amount of physical memory that the VMM should

attempt to map for the HRT

config HRT_COMM_PAGE

hex "GPA of HRT/HVM communication page"

default 0x1fffff000

depends on HVM_HRT

help

Sets the default page address at which the VMM and HRT will

communicate information

config HVM_INT_VEC

int "HVM/HRT Interrupt vector"

default 255

range 33 255

depends on HVM_HRT

help

Sets the interrupt vector to use for communication between

the VMM and the HRT

choice

prompt "HRT Page Size Request"

depends on HVM_HRT

default HRT_PS_2M

help

Requests a given page size to map the initial page tables

from the VMM

config HRT_PS_512G

bool "512GB Pages"

config HRT_PS_1G

bool "1GB Pages"

config HRT_PS_2M

bool "2MB Pages"

config HRT_PS_4K

bool "4KB Pages"

endchoice

config PALACIOS

bool "Support for creating VMs using Palacios"

depends on X86_64_HOST

default 0

config PALACIOS_DIR

depends on PALACIOS

string "Path to Palacios VMM tree"

default "../palacios"

help

Path to the Palacios VMM build. Palacios must be built for

Nautilus, and both palacios/libv3vee.a and libnautilus.a must exist

config PALACIOS_EMBED_VM_IMG

bool "Embed VM image"

depends on PALACIOS

default 0

config PALACIOS_EMBEDDED_VM_IMG

depends on PALACIOS

string "Path to Palacios VM image to embed"

default "management_vm.img"

help

Path to the image that will be embedded

config PALACIOS_MGMT_VM

bool "Launch embedded VM at boot as Management VM"

depends on PALACIOS

default 0

endmenu

menu "Build"

config USE_NAUT_BUILTINS

bool "Use built-in utility functions"

default y

help

Compiles NK with its own implementations of functions

like strcpy etc., as opposed to using the compiler-builtins,

which might not cover all of the ones needed.

config CXX_SUPPORT

bool "Enable C++ support"

default y

help

Compiles the Nautilus kernel with C++ support. Necessary for,

e.g. C++ HRT integration

config RUST_SUPPORT

bool "Enable Rust support"

default n

help

Adds support for Rust code, and builds the Rust example and Shell command

choice

prompt "Compiler and related toolchain to use"

default USE_GCC

help

Chose whether to use GCC or CLang to build Nautilus

Currently, GCC is by far the most tested option

No guarantees that Clang will be able to build everything

config USE_GCC

bool "GCC"

config USE_CLANG

bool "Clang/LLVM"

endchoice

config COMPILER_PREFIX

string "Prefix for compiler toolchain commands"

default ""

help

Relevant toolchain commands are prepended with this string

to allow for cross-compilation, etc

config COMPILER_SUFFIX

string "Suffix for compiler toolchain commands"

default ""

help

Relevant toolchain commands are appended with this string

to allow for different versions, etc

config TOOLCHAIN_ROOT

string "Toolchain Root"

help

Directory where the intended compiler toolchain, binutils, libraries, grub, etc are installed.

You probably want this to be blank and use PATH mechanisms to get the tools you need

endmenu

menu "Configuration"

config MAX_THREADS

int "Maximum number of threads in system"

default 1024

help

Maximum number of threads in system (or any core) at once

config RUN_TESTS_AT_BOOT

bool "Run all tests from the testing framework at boot"

default n

help

This causes the testing framework to be run immediately after

boot and before the shell or runtimes are launched. It will then

exit immediately using QEMU. This allows us to have automated

testing using continuous integration tools.

config THREAD_EXIT_KEYCODE

int "Thread Exit Keycode"

range 1 255

default "196"

help

uses a special thread exit keycode

config USE_TICKETLOCKS

bool "Use Ticket/Bakery locks instead of default spin"

default n

help

Uses ticketlocks (similar to Linux impl.) instead of

default spinlocks

config VIRTUAL_CONSOLE_DISPLAY_NAME

bool "Display name of current virtual console"

default y

help

Puts the name of the current virtual console in the upper left

config VIRTUAL_CONSOLE_CHARDEV_CONSOLE

bool "Place a virtual console interface on a character device"

default n

help

Starts a virtual console interface on a given character device

This allows interaction with VCs much like the VGA console

does

config VIRTUAL_CONSOLE_CHARDEV_CONSOLE_NAME

string "Character device name to use"

default "serial0"

depends on VIRTUAL_CONSOLE_CHARDEV_CONSOLE

help

The character device port name to use for this console

config VIRTUAL_CONSOLE_SERIAL_MIRROR

bool "Mirror virtual console log output to serial"

default n

help

Writes any log output

traffic to serial port in addition to its

target virtual console

config VIRTUAL_CONSOLE_SERIAL_MIRROR_ALL

bool "Mirror all virtual console output to serial"

default n

depends on VIRTUAL_CONSOLE_SERIAL_MIRROR

help

Writes all printfs, logs, puts, putchars, etc

traffic to serial port in addition to their

target virtual consoles; direct displays

(screen clears, display char, etc) are not

currently mirrored.

menu "Scheduler Options"

config UTILIZATION_LIMIT

int "Utilization limit (%)"

range 0 100

default 99

help

The maximum percent utilization the scheduler will allow

on a core. This gives headroom for the scheduler itself.

config SPORADIC_RESERVATION

int "Sporadic reservation (%)"

range 0 100

default 10

help

The percentage utilization the scheduler will dedicate

to sporadic threads and tasks on each core. Sporadic

tasks that exceed this are not admitted, even if

there is time available.

config APERIODIC_RESERVATION

int "Aperiodic reservation (%)"

range 0 100

default 10

help

The percentage utilization the scheduler will dedicate

to aperiodic threads on each core. Aperiodic threads

can exceed this - they also soak up any time not being

used by RT threads.

config HZ

int "Timer Interrupt Frequency"

range 10 10000

default "10"

help

Specifies the tick rate for timers and aperiodic

scheduling. The reciprical of this number is

the scheduling quantum for aperiodic (but not RT)

threads.

config INTERRUPT_REINJECTION_DELAY_NS

int "Interrupt Reinjection Delay (in ns)"

default "10000"

help

If a timer or kick interrupt occurs when the cpu

is not preemptable, it will be reinjected (as a timer

interrupt) after this delay. The result is that

scheduler-driving interrupts is not lost, just delayed.

config AUTO_REAP

bool "Reap threads automatically"

default n

help

Should core zero periodically reap the global

thread list of dead detached threads? Only core 0

does this.

config AUTO_REAP_PERIOD_MS

depends on AUTO_REAP

int "Reaping Period (ms)"

range 10 10000

default "1000"

help

The target period between reaping the global

thread list of dead detached threads.

config WORK_STEALING

bool "Work stealing"

default n

help

If enabled an idle cpu will attempt to steal

runnable threads from other cpus.

config WORK_STEALING_INTERVAL_MS

depends on WORK_STEALING

int "Work stealing interval (ms)"

range 1 10000

default "10"

help

The target period between work-stealing attempts

by the idle thread. This is in terms of

the amount of time the idle thread itself executes

not the real-

config WORK_STEALING_AMOUNT

depends on WORK_STEALING

int "Work stealing amount"

range 1 100

default "4"

help

The number of threads the idle thread will

attempt to steal every time work stealing is

run.

config TASK_IN_SCHED

bool "Handle tasks of known size in scheduler"

default true

help

When enabled, each cpu's scheduler will execute tasks of

known size when no real-time task would be impeded. This

lifts such tasks to a priority just below real-time threads.

Note that the eager EDF properties of the scheduler are maintained -

if an RT thread is runnable, it will still run in preference

to in-scheduler task execution, no matter how much slack is available.

config TASK_THREAD

bool "Handle tasks in a special thread"

default true;

help

When enabled, each cpu has a thread that consumes tasks.

The thread can run at an arbitrary aperiodic priority.

config TASK_THREAD_PRIORITY

depends on TASK_THREAD

int "Aperiodic priority for task threads"

default 100000000

help

Priority for the task threads. The default here is

the quantum in ns. By adjusting this, you can adjust

how much priority unsized tasks effectively have in the system.

config TASK_IN_IDLE

bool "Handle tasks within idle loop"

default false

help

When enabled, each cpu's idle loop will execute tasks prior

to attempting work stealing.

config TASK_IN_IDLE_NOPREEMPT

depends on TASK_IN_IDLE

bool "Execute tasks within idle with preemption disabled"

default false

help

When enabled, the idle loop executes tasks with preemption

disabled, which can result in priority inversion for

real-time threads. However, with preemption enabled, the idle loop

may start a task, then get preempted. The task is then in

limbo until the idle loop is run again, which may be never

given that it has the lowest possible priority in the

system. The purpose of this option is to choose

which of these behaviors you want if you are executing tasks

in idle loops.

config INTERRUPT_THREAD

bool "Restrict interrupts to special real-time interrupt thread"

default false

help

When enabled, all interrupts, except scheduling-related

interrupts, are ignored except when a special, per-core

interrupt thread is running. The interrupt thread is a

periodic real-time thread. This forces interrupt handlers

to start only at well-constrained points in time.

If interrupt handlers are of bounded, known duration, they

also then finish before well-contrained points in time

(max: end of slice + interrupt duration). The downside

of this mechanism is that interrupts are delayed until

the interrupt thread is run, increasing interrupt latency.

Note that threads can insulate themselves from interrupts

outside of this mechanism, using the interrupt_priority_class

mechanism.

config INTERRUPT_THREAD_PERIOD_US

depends on INTERRUPT_THREAD

int "Period for the interrupt thread (us)"

range 500 10000

default 1000

help

The interrupt thread will run this often

config INTERRUPT_THREAD_SLICE_US

depends on INTERRUPT_THREAD

int "Slice for the interrupt thread (us)"

range 100 5000

default 100

help

The interrupt thread will execute for this long when it runs

config INTERRUPT_THREAD_ALLOW_IDLE

depends on INTERRUPT_THREAD

bool "Also allow interrupts when running idle thread"

default false

help

Enable interrupts while running the idle thread

choice

prompt "Scheduling Model For Aperiodic Threads"

default APERIODIC_ROUND_ROBIN

config APERIODIC_DYNAMIC_QUANTUM

bool "Dynamic, Quantum-based Priority"

help

Aperiodic threads have dynamic priority based on a

fixed priority and their runtime within a scheduling quantum.

Longer runtime means lower priority.

config APERIODIC_DYNAMIC_LIFETIME

bool "Dynamic, Lifetime-based Priority"

help

Aperiodic threads have dynamic priority based on a

fixed priority and their total runtime.

Longer runtime means lower priority.

config APERIODIC_LOTTERY

bool "Lottery scheduling"

help

Aperiodic threads are given a random priority based on

the fixed priorities of all aperiodic threads on the core.

config APERIODIC_ROUND_ROBIN

bool "Round-robin scheduling"

help

Aperiodic threads are scheduled round-robbin

endchoice

endmenu

config REAL_MODE_INTERFACE

bool "Enable the Long->Real interface"

default n

help

Allows long mode code in Nautilus to execute real-mode

software interrupts (e.g., BIOS, VESA, etc)

config DEBUG_REAL_MODE_INTERFACE

bool "Debug Long->Real interface"

default n

depends on REAL_MODE_INTERFACE

help

Adds debugging output for the long->real interface

config REAL_MODE_INTERFACE_SEGMENT

hex "Segment (64K total) used for Long->Real interface"

default 0x8000

depends on REAL_MODE_INTERFACE

help

Segment used for the real-mode interface

The first 32K is reserved for the trampoline

code and data. The second 32K can be used by

code invoking real mode interrupts

config ISOCORE

bool "Enable Isolated Core Execution"

default n

help

Allows us to dedicate a core to the

execution of a function without any

interference from other cores

config DEBUG_ISOCORE

bool "Debug Isolated Core Execution"

default n

depends on ISOCORE

help

Adds debugging output for isolated core execution

The low-level code does not have debugging output

config CACHEPART

bool "Enable cache partitioning"

default n

depends on X86_64_HOST

help

Allows cache partitioning

config CACHEPART_THREAD_DEFAULT_PERCENT

int "Percentage of cache to reserve for default use by threads"

range 5 100

default 20

depends on CACHEPART

help

This portion of the cache will be used by threads that make no special requests

config CACHEPART_INTERRUPT

bool "Enable interrupt partition"

default n

depends on CACHEPART

help

Create special partition for interrupts (otherwise they

use the default thread partition)

config CACHEPART_INTERRUPT_PERCENT

int "Percentage of cache to reserve for use by interrupt handlers"

range 5 100

default 10

depends on CACHEPART_INTERRUPT

help

This portion of the cache that will be used by interrupt handlers

config DEBUG_CACHEPART

bool "Debug cache partitioning"

default n

depends on CACHEPART

help

Adds debugging output for cache partitioning

config TEST_CACHEPART

bool "Add cache partitioning tests"

default n

depends on CACHEPART

help

Adds the tests for for cache partitioning

menu "Garbage Collection Options"

config GARBAGE_COLLECTION

bool "Enable Garbage Collection"

default n

help

If enabled, a conservative garbage collector is

used to garbage collect the kernel/HRT. mallocs() pass to the

GC, frees() are ignored, and mallocs can trigger global GC

WARNING: Garbage collection in Nautilus is a highly experimental feature. If you

don't know if you need this, you do not.

choice

prompt "Select Garbage Collector"

depends on GARBAGE_COLLECTION

default ENABLE_PDSGC

config ENABLE_BDWGC

bool "BDWGC"

depends on GARBAGE_COLLECTION

help

If enabled, the BDWGC garbage colector is used.

WARNING: BDWGC integration in Nautilus is a highly experimental feature. If you

don't know if you need this, you do not.

config ENABLE_PDSGC

bool "PDSGC"

depends on GARBAGE_COLLECTION

help

If enabled, the home-grown PDSGC garbage colector is used.

WARNING: PDSGC integration in Nautilus is a highly experimental feature. If you

don't know if you need this, you do not.

endchoice

config ALIGN_BDWGC

bool "Force allocations in the BDWGC garbage collector to be aligned to their own size"

default n

depends on ENABLE_BDWGC

help

If enabled, BDWGC allocations will be aligned to their own size, as in the buddy system allocator

config DEBUG_BDWGC

bool "Debug the BDWGC garbage collector"

default n

depends on ENABLE_BDWGC

help

If enabled, print debugging output from BDWGC

config EXPLICIT_ONLY_PDSGC

bool "Only use PDSGC explictly"

default n

depends on ENABLE_PDSGC

help

If enabled failing mallocs do *not* trigger gc and frees do

deallocation. PDSGC can then be used to explicitly leak check

or explicitly do garbage collection of leaked data

config DEBUG_PDSGC

bool "Debug the PDSGC garbage collector"

default n

depends on ENABLE_PDSGC

help

If enabled, print debugging output from PDSGC

config TEST_BDWGC

bool "Include the BDWGC garbage collection test suite"

default n

depends on ENABLE_BDWGC

help

Adddes test suite for BDWGC, which can be run from the shell

endmenu

endmenu

menu "Optimizations"

config FPU_SAVE

bool "Save FPU state on all context switches"

default y

help

Compiles the kernel to save FPU state on every context switch.

This is not strictly necessary if processors are not virtualized

(by the HRT).

config KICK_SCHEDULE

bool "Kick cores with IPIs on scheduling events"

default n

help

This will reduce the latency and variance of scheduling events

by kicking the remote CPU with an IPI, causing a scheduling event

to occur immediately, rather than waiting for next timer tick or

current thread to yield.

config HALT_WHILE_IDLE

bool "Halt the CPU when idle"

default n

help

This will cause the CPU to go into a halt in an idle thread when

there is nothing else important to run. Can potentially reduce

memory traffic do to yields(), especially on platforms like the

Xeon Phi.

config THREAD_OPTIMIZE

bool "Optimize threading for performance"

default n

help

Disables paranoid condition checking and optimizes thread functions

for maximum performance.

endmenu

menu Debugging

config DEBUG_INFO

bool "Compile with Debug Symbols"

default n

help

Compiles Nautilus with GCC debugging information. This

is useful for remote debugging with GDB and QEMU/BOCHS.

config DEBUG_PRINTS

bool "Enable Debugging Prints"

default n

help

Compiles the Nautilus kernel with debugging prints

config ENABLE_ASSERTS

bool "Enable Runtime Assertions"

default n

help

This will enable runtime assert statements. If this is

disabled, they will not be generated

config PROFILE

bool "Enable Profiling"

default n

help

Profile select function entries and exits

config DEBUG_PROFILE

bool "Debug Profiling"

default n

depends on PROFILE

help

Turn on debug prints for the profiler subsystem

config SILENCE_UNDEF_ERR

bool "Silence Errors for Undefined Functions"

default n

help

Mutes error prints related to undefined

libc compatibility functions. Useful when

porting applications to HRT model.

config ENABLE_STACK_CHECK

bool "Enable Runtime Stack Overrun Checking"

default n

help

This checks the stack pointer on every thread switch to

make sure that a thread hasn't overrun its allocated

stack

config ENABLE_REMOTE_DEBUGGING

depends on !HVM_HRT

bool "Enable Remote Debugging"

default n

help

This allows remote debugging, currently using GDB. It integrates

a GDB stub that talks (currently) via a serial port using

polled operation. You must also enable the relevant port

in the serial configuration under the device section.

Note that the kernel will halt at startup until the

debugger attaches.

config ATTACH_REMOTE_DEBUGGER_AT_BOOT

depends on ENABLE_REMOTE_DEBUGGING

bool "Attach the remote debugger at boot"

default n

help

Attach the remote debugger as part of the initialization

process at boot, before other CPUs are up

config DEBUG_REMOTE_DEBUGGER

depends on ENABLE_REMOTE_DEBUGGING

bool "Debug Remote Debugger"

default n

help

Turn on debug prints for the remote debugger subsystem

config DEBUG_PAGING

bool "Debug Paging"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for paging subsystem

config DEBUG_BOOTMEM

bool "Debug Bootmem Allocator"

depends on DEBUG_PRINTS

default n

help

Turn on debugging for the boot memory allocator

config DEBUG_CMDLINE

bool "Debug Command Line Processing"

depends on DEBUG_PRINTS

default n

help

Turn on debugging for the kernel command line processor

config DEBUG_TESTS

bool "Debug Testing Framework"

depends on DEBUG_PRINTS

default n

help

Turn on debugging for the kernel testing framework

config DEBUG_BUDDY

bool "Debug Buddy Allocator"

depends on DEBUG_PRINTS

default n

help

Turn on debugging for the buddy allocator

config DEBUG_KMEM

bool "Debug Kernel Memory Allocator"

depends on DEBUG_PRINTS

default n

help

Turn on debugging for the high-level kernel

memory allocator (malloc/free)

config DEBUG_FPU

bool "Debug FPU"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for FPU related code (SIMD,MMX,SSE,etc.)

NOTE: Output during FPU init can result in boot failure

if your compiler has optimized print functions assuming

the FPU is already working

config DEBUG_SMP

bool "Debug SMP"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for SMP code

config DEBUG_SHELL

bool "Debug Shell"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for the shell

config DEBUG_HRT

bool "Debug HRT"

depends on DEBUG_PRINTS && HVM_HRT

default n

help

Turn on debug prints for HRT/HVM code

config DEBUG_SFI

bool "Debug SFI"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for SFI platform firmware code

config DEBUG_CXX

bool "Debug C++"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for C++ initialization/support code

config DEBUG_THREADS

bool "Debug Threads"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for threads

config DEBUG_WAITQUEUES

bool "Debug Wait Queues"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for wait queues

YOU PROBABLY DO NOT WANT TO DO THIS - SEE COMMENTS

config DEBUG_GROUP

bool "Debug Groups"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for group

config DEBUG_GROUP_BARRIER

bool "Debug Group Barrier"

depends on DEBUG_GROUP

default n

help

Turn on debug prints for group barrier

config DEBUG_SCHED

bool "Debug Scheduler"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for the scheduler

config DEBUG_GROUP_SCHED

bool "Debug Group Scheduling"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for group scheduling

config DEBUG_TIMERS

bool "Debug Timers"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for timer subsystem

config DEBUG_SEMAPHORES

bool "Debug Semaphores"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for semaphores

config DEBUG_MSG_QUEUES

bool "Debug Message Queues"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for message queues

config DEBUG_SYNCH

bool "Debug Synchronization"

depends on DEBUG_PRINTS

default n

help

Turns on debug prints for synchronization functions

(rwlock, condvar)

config DEBUG_BARRIER

bool "Debug Barriers"

depends on DEBUG_PRINTS

default n

help

Turns on debug prints for barriers

config DEBUG_NUMA

bool "Debug NUMA code"

depends on DEBUG_PRINTS

default n

help

Turns on debug prints for NUMA code

config DEBUG_VIRTUAL_CONSOLE

bool "Debug Virtual Console"

default n

help

Turn on debug output for VC

config DEBUG_DEV

bool "Debug Base Device Interface"

default n

help

Turn on debug output for base device interface

config DEBUG_CHARDEV

bool "Debug Character Device Interface"

depends on DEBUG_DEV

default n

help

Turn on debug output for character device interface

config DEBUG_BLKDEV

bool "Debug Block Device Interface"

depends on DEBUG_DEV

default n

help

Turn on debug output for block device interface

config DEBUG_NETDEV

bool "Debug Network Device Interface"

depends on DEBUG_DEV

default n

help

Turn on debug output for network device interface

config DEBUG_FILESYSTEM

bool "Debug Base Filesystem Interface"

depends on DEBUG_PRINTS

default n

help

Turn on debug prints for the filesystem interface

config DEBUG_LOADER

bool "Debug loader"

depends on DEBUG_PRINTS

default n