Some architectures such as RISC-v support more than 255 interrupts
per aggrigator. This diff adds the ability to forgo the aggrigator
pattern and use a configurable number of bits for multilevel
interruts.
Signed-off-by: Joshua Lilly <jgl@meta.com>
This is meant as a substitute for sys_clock_timeout_end_calc()
Current sys_clock_timeout_end_calc() usage opens up many bug
possibilities due to the actual timeout evaluation's open-coded nature.
Issue ##50611 is one example.
- Some users store the returned value in a signed variable, others in
an unsigned one, making the comparison with UINT64_MAX (corresponding
to K_FOREVER) wrong in the signed case.
- Some users compute the difference and store that in a signed variable
to compare against 0 which still doesn't work with K_FOREVER. And when
this difference is used as a timeout argument then the K_FOREVER
nature of the timeout is lost.
- Some users complexify their code by special-casing K_NO_WAIT and
K_FOREVER inline which is bad for both code readability and binary
size.
Let's introduce a better abstraction to deal with absolute timepoints
with an opaque type to be used with a well-defined API.
The word "timeout" was avoided in the naming on purpose as the timeout
namespace is quite crowded already and it is preferable to make a
distinction between relative time periods (timeouts) and absolute time
values (timepoints).
A few stacks are also adjusted as they were too tight on X86.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Scheduling relative timeouts from within timer callbacks (=sys clock ISR
context) differs from scheduling relative timeouts from an application
context.
This change documents and explains the rationale of this distinction.
Signed-off-by: Florian Grandel <fgrandel@code-for-humans.de>
cooperative priorities are negative, 0 is not a cooperative priority.
Looks like the docs are showing an outdated diagram for some reason, try
to update that with a refresh.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Updates the data passing summary table to indicate that the size of
a message queue data item must be a multiple of its data alignment.
This brings the documentation in both the summary table and the
message queue documentation into alignment.
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
Updates the FIFO and LIFO documentation to clarify behavior
surrounding re-adding data items to queues.
Fixes#56336
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
As both C and C++ standards require applications running under an OS to
return 'int', adapt that for Zephyr to align with those standard. This also
eliminates errors when building with clang when not using -ffreestanding,
and reduces the need for compiler flags to silence warnings for both clang
and gcc.
Signed-off-by: Keith Packard <keithp@keithp.com>
Augment the doc with functionality added in commit a211970b42 ("riscv:
improve contended FPU switching").
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
FPU context switching is always performed on demand through the FPU
access exception handler. Actual task switching only grants or denies
FPU access depending on the current FPU owner.
Because RISC-V doesn't have a dedicated FPU access exception, we must
catch the Illegal Instruction exception and look for actual FP opcodes.
There is no longer a need to allocate FPU storage on the stack for every
exception making esf smaller and stack overflows less likely.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
If a semaphore is contested, it is possible that the semaphore will no
longer be available when k_sem_take() is called, not k_sem_give().
Fix few typos and explicitly mention poll events instead of "they".
Signed-off-by: Tomasz Moń <tomasz.mon@nordicsemi.no>
The commit c844bd87b3 removed the support
for passing a memory block (allocated in a memory pool) as message
data, but did not update the relevant documentation.
This commit removes any references to the memory block support, which
was removed in the v2.5.0 release, in the mailbox API documentation.
Signed-off-by: Stephanos Ioannidis <stephanos.ioannidis@nordicsemi.no>
The pipes implementation has been updated to allow ISRs to both
send and receive data to/from pipes provided the K_NO_WAIT timeout
option is used.
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
Updates the priority inheritance description to better explain what
happens during priority inheritance and warn of the consequences of
not following best-practices.
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
The kernel documentation listed the memory management API pages under
two different sections: 'Kernel/Kernel Services' and
'Kernel/Memory Management' -- this creates unnecessary confusion and
makes it hard to look up all supported kernel memory management APIs.
This commit relocates the memory management API pages under
'Kernel/Kernel Services' to 'Kernel/Memory Management' so that all
memory management APIs provided by the kernel are described in one
unified section.
The link to the 'Kernel/Memory Management' index page is still left in
the 'Kernel Services' page because it may still be helpful to look at
it as part of the services provided by the Zephyr kernel -- it is just
more substantial than the rest and deserves more visibility.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
This commit adds the 'Language Support' sub-category under the
'Developing with Zephyr' category with programming language support-
related documentations.
The contents of the 'C standard library' page have been relocated to
the 'C Language Support' page, and the contents of the 'C++ Support for
Applications' page have been relocated to the 'C++ Language Support'
page.
Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
Moves the 'Flushing a Pipe' code example to the correct location
and section and re-adds the 'Suggested Uses' text missing
compared to v2.7.
Signed-off-by: Archie Atkinson <archie.atkinson@chiaro.co.uk>
At some recent point, directory <zephyr-root>/include was moved to
<zephyr-root>/include/zephyr. However, links from documentation to
Zephyr source on Github were not updated. Update them now.
Signed-off-by: Aleksandar Markovic <aleksandar.markovic.sa@gmail.com>
Updates the threads documentation to clarify the distinction between
ready and running states.
Fixes 44255
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
