These stacks are appropriate for threads that run purely in
supervisor mode, and also as stacks for interrupt and exception
handling.
Two new arch defines are introduced:
- ARCH_KERNEL_STACK_GUARD_SIZE
- ARCH_KERNEL_STACK_OBJ_ALIGN
New public declaration macros:
- K_KERNEL_STACK_RESERVED
- K_KERNEL_STACK_EXTERN
- K_KERNEL_STACK_DEFINE
- K_KERNEL_STACK_ARRAY_DEFINE
- K_KERNEL_STACK_MEMBER
- K_KERNEL_STACK_SIZEOF
If user mode is not enabled, K_KERNEL_STACK_* and K_THREAD_STACK_*
are equivalent.
Separately generated privilege elevation stacks are now declared
like kernel stacks, removing the need for K_PRIVILEGE_STACK_ALIGN.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
The core kernel computes the initial stack pointer
for a thread, properly aligning it and subtracting out
any random offsets or thread-local storage areas.
arch_new_thread() no longer needs to make any calculations,
an initial stack frame may be placed at the bounds of
the new 'stack_ptr' parameter passed in. This parameter
replaces 'stack_size'.
thread->stack_info is now set before arch_new_thread()
is invoked, z_new_thread_init() has been removed.
The values populated may need to be adjusted on arches
which carve-out MPU guard space from the actual stack
buffer.
thread->stack_info now has a new member 'delta' which
indicates any offset applied for TLS or random offset.
It's used so the calculations don't need to be repeated
if the thread later drops to user mode.
CONFIG_INIT_STACKS logic is now performed inside
z_setup_new_thread(), before arch_new_thread() is called.
thread->stack_info is now defined as the canonical
user-accessible area within the stack object, including
random offsets and TLS. It will never include any
carved-out memory for MPU guards and must be updated at
runtime if guards are removed.
Available stack space is now optimized. Some arches may
need to significantly round up the buffer size to account
for page-level granularity or MPU power-of-two requirements.
This space is now accounted for and used by virtue of
the Z_THREAD_STACK_SIZE_ADJUST() call in z_setup_new_thread.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Replace DT_PHYS_RAM_ADDR and DT_RAM_SIZE with DT_REG_ADDR/DT_REG_SIZE
for the DT_CHOSEN(zephyr_sram) node.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
This operation is formally defined as rounding down a potential
stack pointer value to meet CPU and ABI requirments.
This was previously defined ad-hoc as STACK_ROUND_DOWN().
A new architecture constant ARCH_STACK_PTR_ALIGN is added.
Z_STACK_PTR_ALIGN() is defined in terms of it. This used to
be inconsistently specified as STACK_ALIGN or STACK_PTR_ALIGN;
in the latter case, STACK_ALIGN meant something else, typically
a required alignment for the base of a stack buffer.
STACK_ROUND_UP() only used in practice by Risc-V, delete
elsewhere.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Promote the private z_arch_* namespace, which specifies
the interface between the core kernel and the
architecture code, to a new top-level namespace named
arch_*.
This allows our documentation generation to create
online documentation for this set of interfaces,
and this set of interfaces is worth treating in a
more formal way anyway.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
