Say threadA holds a mutex and threadB tries
to lock it with a timeout, a race would occur
if threadA unlock that mutex after threadB
got unpended by sys_clock and before it gets
scheduled and calls k_spin_lock.
This patch fixes this issue by checking the
mutex's status again after k_spin_lock calls.
Fixes#48056
Signed-off-by: Qi Yang <qi.yang@cmind-semi.com>
In order to bring consistency in-tree, migrate all kernel code to the
new prefix <zephyr/...>. Note that the conversion has been scripted,
refer to zephyrproject-rtos#45388 for more details.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
Removes an unnecessary schedule lock/unlock pair from k_mutex_unlock().
Rationale: Given that only the current thread (which would also be the
mutex owner) will be able to modify the mutex object AND that a
recursive unlock ought never trigger any reschedule (as it does not
touch the pend queue), then performing a schedule lock is not needed
prior to testing for a recursive unlock.
Furthermore, even if it is not a recursive unlock, then a schedule lock
is superfluous as the existing spinlock provides sufficient protection.
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
If you try to unlock an unlocked mutex, it will incorrectly
succeeds and decreases the lock count to -1.
Fixes#36572
Signed-off-by: Chih Hung Yu <chyu313@gmail.com>
Changed location of the last k_mutex_unlock trace hook since it was
being called after k_sched_unlock, which could result in tracing
scenarios (other thread waiting for lock) where it appeared that a
mutex was being locked again before becoming unlocked.
Signed-off-by: Torbjörn Leksell <torbjorn.leksell@percepio.com>
Remove this intrusive tracing feature in favor of the new object tracing
using the main tracing feature in zephyr. See #33603 for the new tracing
coverage for all objects.
This will allow for support in more tools and less reliance on GDB for
tracing objects.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Most of kernel files where declaring os module without providing
log level. Because of that default log level was used instead of
CONFIG_KERNEL_LOG_LEVEL.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
Now that device_api attribute is unmodified at runtime, as well as all
the other attributes, it is possible to switch all device driver
instance to be constant.
A coccinelle rule is used for this:
@r_const_dev_1
disable optional_qualifier
@
@@
-struct device *
+const struct device *
@r_const_dev_2
disable optional_qualifier
@
@@
-struct device * const
+const struct device *
Fixes#27399
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Mutex operations check ownership against _current. But in an
ISR, _current is just whatever thread was interrupted when the
ISR fired. Explicitly do not allow this.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Add a k_timeout_t type, and use it everywhere that kernel API
functions were accepting a millisecond timeout argument. Instead of
forcing milliseconds everywhere (which are often not integrally
representable as system ticks), do the conversion to ticks at the
point where the timeout is created. This avoids an extra unit
conversion in some application code, and allows us to express the
timeout in units other than milliseconds to achieve greater precision.
The existing K_MSEC() et. al. macros now return initializers for a
k_timeout_t.
The K_NO_WAIT and K_FOREVER constants have now become k_timeout_t
values, which means they cannot be operated on as integers.
Applications which have their own APIs that need to inspect these
vs. user-provided timeouts can now use a K_TIMEOUT_EQ() predicate to
test for equality.
Timer drivers, which receive an integer tick count in ther
z_clock_set_timeout() functions, now use the integer-valued
K_TICKS_FOREVER constant instead of K_FOREVER.
For the initial release, to preserve source compatibility, a
CONFIG_LEGACY_TIMEOUT_API kconfig is provided. When true, the
k_timeout_t will remain a compatible 32 bit value that will work with
any legacy Zephyr application.
Some subsystems present timeout (or timeout-like) values to their own
users as APIs that would re-use the kernel's own constants and
conventions. These will require some minor design work to adapt to
the new scheme (in most cases just using k_timeout_t directly in their
own API), and they have not been changed in this patch, instead
selecting CONFIG_LEGACY_TIMEOUT_API via kconfig. These subsystems
include: CAN Bus, the Microbit display driver, I2S, LoRa modem
drivers, the UART Async API, Video hardware drivers, the console
subsystem, and the network buffer abstraction.
k_sleep() now takes a k_timeout_t argument, with a k_msleep() variant
provided that works identically to the original API.
Most of the changes here are just type/configuration management and
documentation, but there are logic changes in mempool, where a loop
that used a timeout numerically has been reworked using a new
z_timeout_end_calc() predicate. Also in queue.c, a (when POLL was
enabled) a similar loop was needlessly used to try to retry the
k_poll() call after a spurious failure. But k_poll() does not fail
spuriously, so the loop was removed.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
k_mutex_unlock will now perform error checking and return on failures.
If the current thread does not own the mutex, we will now return -EPERM.
In the unlikely situation where we own a lock and the lock count is
zero, we assert. This is considered an undefined bahviour and should not
happen.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
The k_mutex is a priority-inheriting mutex, so on unlock it's possible
that a thread's priority will be lowered. Make this a reschedule
point so that reasoning about thread priorities is easier (possibly at
the cost of performance): most users are going to expect that the
priority elevation stops at exactly the moment of unlock.
Note that this also reorders the code to fix what appear to be obvious
race conditions. After the call to z_ready_thread(), that thread may
be run (e.g. by an interrupt preemption or on another SMP core), yet
the return value and mutex weren't correctly set yet. The spinlock
was also prematurely released.
Fixes#20802
Signed-off-by: Andy Ross <andrew.j.ross@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>
This commit refactors kernel and arch headers to establish a boundary
between private and public interface headers.
The refactoring strategy used in this commit is detailed in the issue
This commit introduces the following major changes:
1. Establish a clear boundary between private and public headers by
removing "kernel/include" and "arch/*/include" from the global
include paths. Ideally, only kernel/ and arch/*/ source files should
reference the headers in these directories. If these headers must be
used by a component, these include paths shall be manually added to
the CMakeLists.txt file of the component. This is intended to
discourage applications from including private kernel and arch
headers either knowingly and unknowingly.
- kernel/include/ (PRIVATE)
This directory contains the private headers that provide private
kernel definitions which should not be visible outside the kernel
and arch source code. All public kernel definitions must be added
to an appropriate header located under include/.
- arch/*/include/ (PRIVATE)
This directory contains the private headers that provide private
architecture-specific definitions which should not be visible
outside the arch and kernel source code. All public architecture-
specific definitions must be added to an appropriate header located
under include/arch/*/.
- include/ AND include/sys/ (PUBLIC)
This directory contains the public headers that provide public
kernel definitions which can be referenced by both kernel and
application code.
- include/arch/*/ (PUBLIC)
This directory contains the public headers that provide public
architecture-specific definitions which can be referenced by both
kernel and application code.
2. Split arch_interface.h into "kernel-to-arch interface" and "public
arch interface" divisions.
- kernel/include/kernel_arch_interface.h
* provides private "kernel-to-arch interface" definition.
* includes arch/*/include/kernel_arch_func.h to ensure that the
interface function implementations are always available.
* includes sys/arch_interface.h so that public arch interface
definitions are automatically included when including this file.
- arch/*/include/kernel_arch_func.h
* provides architecture-specific "kernel-to-arch interface"
implementation.
* only the functions that will be used in kernel and arch source
files are defined here.
- include/sys/arch_interface.h
* provides "public arch interface" definition.
* includes include/arch/arch_inlines.h to ensure that the
architecture-specific public inline interface function
implementations are always available.
- include/arch/arch_inlines.h
* includes architecture-specific arch_inlines.h in
include/arch/*/arch_inline.h.
- include/arch/*/arch_inline.h
* provides architecture-specific "public arch interface" inline
function implementation.
* supersedes include/sys/arch_inline.h.
3. Refactor kernel and the existing architecture implementations.
- Remove circular dependency of kernel and arch headers. The
following general rules should be observed:
* Never include any private headers from public headers
* Never include kernel_internal.h in kernel_arch_data.h
* Always include kernel_arch_data.h from kernel_arch_func.h
* Never include kernel.h from kernel_struct.h either directly or
indirectly. Only add the kernel structures that must be referenced
from public arch headers in this file.
- Relocate syscall_handler.h to include/ so it can be used in the
public code. This is necessary because many user-mode public codes
reference the functions defined in this header.
- Relocate kernel_arch_thread.h to include/arch/*/thread.h. This is
necessary to provide architecture-specific thread definition for
'struct k_thread' in kernel.h.
- Remove any private header dependencies from public headers using
the following methods:
* If dependency is not required, simply omit
* If dependency is required,
- Relocate a portion of the required dependencies from the
private header to an appropriate public header OR
- Relocate the required private header to make it public.
This commit supersedes #20047, addresses #19666, and fixes#3056.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
z_set_thread_return_value is part of the core kernel -> arch
interface and has been renamed to z_arch_thread_return_value_set.
z_set_thread_return_value_with_data renamed to
z_thread_return_value_set_with_data for consistency.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
System call arguments, at the arch layer, are single words. So
passing wider values requires splitting them into two registers at
call time. This gets even more complicated for values (e.g
k_timeout_t) that may have different sizes depending on configuration.
This patch adds a feature to gen_syscalls.py to detect functions with
wide arguments and automatically generates code to split/unsplit them.
Unfortunately the current scheme of Z_SYSCALL_DECLARE_* macros won't
work with functions like this, because for N arguments (our current
maximum N is 10) there are 2^N possible configurations of argument
widths. So this generates the complete functions for each handler and
wrapper, effectively doing in python what was originally done in the
preprocessor.
Another complexity is that traditional the z_hdlr_*() function for a
system call has taken the raw list of word arguments, which does not
work when some of those arguments must be 64 bit types. So instead of
using a single Z_SYSCALL_HANDLER macro, this splits the job of
z_hdlr_*() into two steps: An automatically-generated unmarshalling
function, z_mrsh_*(), which then calls a user-supplied verification
function z_vrfy_*(). The verification function is typesafe, and is a
simple C function with exactly the same argument and return signature
as the syscall impl function. It is also not responsible for
validating the pointers to the extra parameter array or a wide return
value, that code gets automatically generated.
This commit includes new vrfy/msrh handling for all syscalls invoked
during CI runs. Future commits will port the less testable code.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The mutex locking was written to use k_sched_lock(), which doesn't
work as a synchronization primitive if there is another CPU running
(it prevents the current CPU from preempting the thread, it says
nothing about what the others are doing).
Use the pre-existing spinlock for all synchronization. One wrinkle is
that the priority code was needing to call z_thread_priority_set(),
which is a rescheduling call that cannot be called with a lock held.
So that got split out with a low level utility that can update the
schedule state but allow the caller to defer yielding until later.
Fixes#17584
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
move misc/dlist.h to sys/dlist.h and
create a shim for backward-compatibility.
No functional changes to the headers.
A warning in the shim can be controlled with CONFIG_COMPAT_INCLUDES.
Related to #16539
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
move tracing.h to debug/tracing.h and
create a shim for backward-compatibility.
No functional changes to the headers.
A warning in the shim can be controlled with CONFIG_COMPAT_INCLUDES.
Related to #16539
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Given that the section name and boundary simbols can be inferred from
the struct object name, it makes sense to create an iterator that
abstracts away the access details and reduce the possibility for
mistakes.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
There are some remaining code from object monitoring which simply
expands to empty loop macros. Remove them as they are not
functional anyway.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Update reserved function names starting with one underscore, replacing
them as follows:
'_k_' with 'z_'
'_K_' with 'Z_'
'_handler_' with 'z_handl_'
'_Cstart' with 'z_cstart'
'_Swap' with 'z_swap'
This renaming is done on both global and those static function names
in kernel/include and include/. Other static function names in kernel/
are renamed by removing the leading underscore. Other function names
not starting with any prefix listed above are renamed starting with
a 'z_' or 'Z_' prefix.
Function names starting with two or three leading underscores are not
automatcally renamed since these names will collide with the variants
with two or three leading underscores.
Various generator scripts have also been updated as well as perf,
linker and usb files. These are
drivers/serial/uart_handlers.c
include/linker/kobject-text.ld
kernel/include/syscall_handler.h
scripts/gen_kobject_list.py
scripts/gen_syscall_header.py
Signed-off-by: Patrik Flykt <patrik.flykt@intel.com>
Use a subsystem lock, not a per-object lock. Really we want to lock
at mutex granularity where possible, but (1) that has non-trivial
memory overhead vs. e.g. directly spinning on the mutex state and (2)
the locking in a few places was originally designed to protect access
to the mutex *owner* priority, which is not 1:1 with a single mutex.
Basically the priority-inheriting mutex code will need some rework
before it works as a fine-grained locking abstraction in SMP.
Note that this fixes an invisible bug: with the older code,
k_mutex_unlock() would actually call irq_unlock() twice along the path
where there was a new owner, which is benign on existing architectures
(so long as the key argument is unchanged) but was never guaranteed to
work. With a spinlock, unlocking an unlocked/unowned lock is a
detectable assertion condition.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Just like with _Swap(), we need two variants of these utilities which
can atomically release a lock and context switch. The naming shifts
(for byte count reasons) to _reschedule/_pend_curr, and both have an
_irqlock variant which takes the traditional locking.
Just refactoring. No logic changes.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
It is necessary to delay setting lock_count = 0 because an unlocking thread
maybe swapped out when it calls adjust_owner_prio(). If the thread that starts
running sees lock_count = 0 it will successfully acquire the mutex even though
it is not fully unlocked yet.
Fixes#11798.
Signed-off-by: Nicolás Bértolo <nicolasbertolo@gmail.com>
This is not violating any MISRA-C rule, though, it seems to be
triggering a false (rule 9.1) positive in some static analysis
tools. Nevertheless, it is more readable declare all variables in the
same scope together.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Make if statement using pointers explicitly check whether the value is
NULL or not.
The C standard does not say that the null pointer is the same as the
pointer to memory address 0 and because of this is a good practice
always compare with the macro NULL.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Define generic interface and hooks for tracing to replace
kernel_event_logger and existing tracing facilities with something more
common.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
irq_lock returns an unsigned int, though, several places was using
signed int. This commit fix this behaviour.
In order to avoid this error happens again, a coccinelle script was
added and can be used to check violations.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
There were multiple spots where code was using the _wait_q_t
abstraction as a synonym for a dlist and doing direct list management
on them with the dlist APIs. Refactor _wait_q_t into a proper opaque
struct (not a typedef for sys_dlist_t) and write a simple wrapper API
for the existing usages. Now replacement of wait_q with a different
data structure is much cleaner.
Note that there were some SYS_DLIST_FOR_EACH_SAFE loops in mailbox.c
that got replaced by the normal/non-safe macro. While these loops do
mutate the list in the code body, they always do an early return in
those circumstances instead of returning into the macro'd for() loop,
so the _SAFE usage was needless.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The various macros to do checks in system call handlers all
implictly would generate a kernel oops if a check failed.
This is undesirable for a few reasons:
* System call handlers that acquire resources in the handler
have no good recourse for cleanup if a check fails.
* In some cases we may want to propagate a return value back
to the caller instead of just killing the calling thread,
even though the base API doesn't do these checks.
These macros now all return a value, if nonzero is returned
the check failed. K_OOPS() now wraps these calls to generate
a kernel oops.
At the moment, the policy for all APIs has not changed. They
still all oops upon a failed check/
The macros now use the Z_ notation for private APIs.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Almost everywhere this was called, it was immediately followed by
_abort_thread_timeout(), for obvious reasons. The only exceptions
were in timeout and k_timer expiration (unifying these two would be
another good cleanup), which are peripheral parts of the scheduler and
can plausibly use a more "internal" API.
So make the common case the default, and expose the old behavior as
_unpend_thread_no_timeout(). (Along with identical changes for
_unpend_first_thread) Saves code bytes and simplifies scheduler
surface area for future synchronization work.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Recent changes to the scheduler API means we can simplify this
further: move the assignment to mutex->owner outside the if(), which
removes the need to have an else clause (which just set that field to
NULL when the new_owner was already NULL); and we can likewise move
the irq_unlock() outside the block.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Recent changes have eliminated most use of _Swap() in favor of higher
level scheduler abstractions. We can remove the header too.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Everywhere the current thread is pended, the code is going to have to
do a _Swap() soon afterward, yet the scheduler API exposed these as
separate steps. Unify this pattern everywhere it appears, which saves
some code bytes and gets _Swap() out of the general scheduler API at
zero cost.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The xtensa-asm2 work included a patch that added nano_internal.h
includes in lots of places that needed to have _Swap defined, because
it had to break a cycle and this no longer got pulled in from the arch
headers.
Unfortunately those new includes created new and more amusing cycles
elsewhere which led to breakage on other platforms.
Break out the _Swap definition (only) into a separate header and use
that instead. Cleaner. Seems not to have any more hidden gotchas.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
_Swap() is defined in nano_internal.h. Everything calls _Swap().
Pretty much nothing that called _Swap() included nano_internal.h,
expecting it to be picked up automatically through other headers (as
it happened, from the kernel arch-specific include file). A new
_Swap() is going to need some other symbols in the inline definition,
so I needed to break that cycle. Now nothing sees _Swap() defined
anymore. Put nano_internal.h everywhere it's needed.
Our kernel includes remain a big awful yucky mess. This makes things
more correct but no less ugly. Needs cleanup.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Qi Yang
Gerard Marull-Paretas
Peter Mitsis
Nazar Kazakov
Chih Hung Yu
Torbjörn Leksell
Anas Nashif
Krzysztof Chruscinski
Tomasz Bursztyka
Kumar Gala
Andrew Boie
Andy Ross
Steven Wang
Stephanos Ioannidis
Nicolas Pitre
Patrik Flykt
Daniel Leung
Nicolás Bértolo
Flavio Ceolin
Adithya Baglody
Leandro Pereira