zephyr/kernel/Kconfig.mem_domain

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# Kernel configuration options
# Copyright (c) 2014-2015 Wind River Systems, Inc.
# SPDX-License-Identifier: Apache-2.0
menu "Memory Domains"
config MAX_DOMAIN_PARTITIONS
int "Maximum number of partitions per memory domain"
default 16
range 0 255
depends on USERSPACE
help
Configure the maximum number of partitions per memory domain.
config ARCH_MEM_DOMAIN_DATA
bool
depends on USERSPACE
help
This hidden option is selected by the target architecture if
architecture-specific data is needed on a per memory domain basis.
If so, the architecture defines a 'struct arch_mem_domain' which is
embedded within every struct k_mem_domain. The architecture
must also define the arch_mem_domain_init() function to set this up
when a memory domain is created.
Typical uses might be a set of page tables for that memory domain.
config ARCH_MEM_DOMAIN_SYNCHRONOUS_API
bool
depends on USERSPACE
help
This hidden option is selected by the target architecture if
modifying a memory domain's partitions at runtime, or changing
a memory domain's thread membership requires synchronous calls
into the architecture layer.
If enabled, the architecture layer must implement the following
APIs:
arch_mem_domain_thread_add
arch_mem_domain_thread_remove
arch_mem_domain_partition_remove
arch_mem_domain_partition_add
It's important to note that although supervisor threads can be
members of memory domains, they have no implications on supervisor
thread access to memory. Memory domain APIs may only be invoked from
supervisor mode.
For these reasons, on uniprocessor systems unless memory access
policy is managed in separate software constructions like page
tables, these APIs don't need to be implemented as the underlying
memory management hardware will be reprogrammed on context switch
anyway.
config ARCH_MEM_DOMAIN_SUPPORTS_ISOLATED_STACKS
bool
help
This hidden option is selected by the target architecture if
the architecture supports isolating thread stacks for threads
within the same memory domain.
config MEM_DOMAIN_ISOLATED_STACKS
bool
default y
depends on (MMU || MPU) && ARCH_MEM_DOMAIN_SUPPORTS_ISOLATED_STACKS
help
If enabled, thread stacks within the same memory domains are
isolated which means threads within the same memory domains
have no access to others threads' stacks.
If disabled, threads within the same memory domains can access
other threads' stacks.
Regardless of this settings, threads cannot access the stacks of
threads outside of their domains.
endmenu