The implementation of Z_TIMEOUT_US() and Z_TIMEOUT_NS() in the legacy
timeout API is incorrect in that it multiplies the input value by the
scale factor rather than dividing it, making K_USEC(3) equivalent to
K_SECONDS(3). Replace with implementation that doesn't surprise a
user that happens to find and use them.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
Struct definitions contain no inlines that depend on other code so
should live early in the include tree. Upcoming refactoring needs
this to break header dependency cycles. The kernel_structs.h header
was designed for exactly this purpose.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Add support for "absolute" timeouts, which are expressed relative to
system uptime instead of deltas from current time. These allow for
more race-resistant code to be written by allowing application code to
do a single timeout computation, once, and then reuse the timeout
value even if the thread wakes up and needs to suspend again later.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Add a CONFIG_TIMEOUT_64BIT kconfig that, when selected, makes the
k_ticks_t used in timeout computations pervasively 64 bit. This will
allow much longer timeouts and much faster (i.e. more precise) tick
rates. It also enables the use of absolute (not delta) timeouts in an
upcoming commit.
Signed-off-by: Andy Ross <andrew.j.ross@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>
Kernel timeouts have always been a 32 bit integer despite the
existence of generation macros, and existing code has been
inconsistent about using them. Upcoming commits are going to make the
timeout arguments opaque, so fix things up to be rigorously correct.
Changes include:
+ Adding a K_TIMEOUT_EQ() macro for code that needs to compare timeout
values for equality (e.g. with K_FOREVER or K_NO_WAIT).
+ Adding a k_msleep() synonym for k_sleep() which can continue to take
integral arguments as k_sleep() moves away to timeout arguments.
+ Pervasively using the K_MSEC(), K_SECONDS(), et. al. macros to
generate timeout arguments.
+ Removing the usage of K_NO_WAIT as the final argument to
K_THREAD_DEFINE(). This is just a count of milliseconds and we need
to use a zero.
This patch include no logic changes and should not affect generated
code at all.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The macro was having "t" as a parameter but then used "X" when
calling k_cyc_to_ns_floor64(X). This caused a compile error.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
The addition of API to correctly handle conversion between durations
in different clocks inadvertently changed the type of the value
produced by the API. Specific changes were:
s32_t z_ms_to_ticks(s32_t t) =>
u32_t k_ms_to_ticks_ceil32(u32_t t) : signedness change
s32_t __ticks_to_us(s32_t t) =>
u64_t k_ticks_to_us_floor64(u64_t t) : signedness and rank change
s32_t z_us_to_ticks(s32_t t) =>
u64_t k_us_to_ticks_ceil64(u64_t t) : signedness and rank change
int sys_clock_hw_cycles_per_tick() =>
u32_t k_ticks_to_cyc_floor32(1) : signedness change
The effect of this is to change the essential type of operands in
existing expressions, potentially resulting in behavior changes when
calculations were promoted to unsigned types, or code size by
requiring 64-bot arithmetic.
Add casts as necessary to preserve the original return type, and to
explicitly recognize impact of passing macro parameters into a context
where a specific type will be used.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
Mark the old time conversion APIs deprecated, leave compatibility
macros in place, and replace all usage with the new API.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Remove the older time conversion utilities and use the new ones
exclusively, with preprocessor macros to provide the older symbols for
compatibility.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Zephyr has always had an ad hoc collection of time unit macros and
conversion routines in a selection of different units, precisions,
rounding modes and naming conventions.
This adds a single optimized generator to produce any such conversion,
and enumerates it to produce a collection of 48 utilities in all
useful combinations as a single supported kernel API going forward.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Consistently place C++ use of extern "C" after all include directives,
within the negative branch of _ASMLANGUAGE if used.
The inclusion of the generated syscall files is placed outside the
extern "C" block as the generated file has its own extern "C" block.
Background from issue #17997:
Declarations that use C linkage should be placed within extern "C"
so the language linkage is correct when the header is included by
a C++ compiler.
Similarly #include directives should be outside the extern "C" to
ensure the language-specific default linkage is applied to any
declarations provided by the included header.
See: https://en.cppreference.com/w/cpp/language/language_linkage
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
move misc/util.h to sys/util.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 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>
If the system sets its clock frequency at runtime, this is
stored in a variable that can't be directly read by user
mode. For this case only, add a system call to fetch its
value and modify the definition of
sys_clock_hw_cycles_per_sec() to use it.
Since this is now a system call, store in a temporary variable
inside z_ms_to_ticks(). The syscall overhead only applies
when called from user mode, other contexts are completely
inlined.
Added stub syscall header for mocking framework, to get rid
of inclusion errors.
Fixes: #16238
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Add k_usleep() API, analogous to k_sleep(), excepting that the argument
is in microseconds rather than milliseconds.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
The two branches of the compile-time conditional are identical, so
they are consolidated and the conditional removed.
Just hygiene again. No functional change.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
This is just hygiene. Some preprocessor logic is optimized, eliminating
a temporary (_NON_OPTIMIZED_TICKS_PER_SEC) in the process.
Signed-off-by: Charles E. Youse <charles.youse@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>
I was pretty careful, but these snuck in. Most of them are due to
overbroad string replacements in comments. The pull request is very
large, and I'm too lazy to find exactly where to back-merge all of
these.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Now that the API has been fixed up, replace the existing timeout queue
with a much smaller version. The basic algorithm is unchanged:
timeouts are stored in a sorted dlist with each node nolding a delta
time from the previous node in the list; the announce call just walks
this list pulling off the heads as needed. Advantages:
* Properly spinlocked and SMP-aware. The earlier timer implementation
relied on only CPU 0 doing timeout work, and on an irq_lock() being
taken before entry (something that was violated in a few spots).
Now any CPU can wake up for an event (or all of them) and everything
works correctly.
* The *_thread_timeout() API is now expressible as a clean wrapping
(just one liners) around the lower-level interface based on function
pointer callbacks. As a result the timeout objects no longer need
to store backpointers to the thread and wait_q and have shrunk by
33%.
* MUCH smaller, to the tune of hundreds of lines of code removed.
* Future proof, in that all operations on the queue are now fronted by
just two entry points (_add_timeout() and z_clock_announce()) which
can easily be augmented with fancier data structures.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
_timeout_remaining_get() was a function on a struct _timeout, doing
iteration on the timeout list, but it was defined in timer.c (the
higher level abstraction).
Move it to where it belongs. Also have it return ticks instead of ms
to conform to scheme in the rest of the timeout API. And rename it to
a more standard zephyr name.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Not sure why this was here. The point to this API (which is poorly
explained) is to "round up" requested timeout values to an integer
number of ticks in the future, so the timeouts don't expire too soon.
There's no change of that requirement in tickless mode. While the
"tick" unit will typicaly be a much smaller time (and thus much less
likely to have this kind of aliasing bug), we STILL don't want early
expiration.
And as with everything else in tickless, changing this breaks no
tests. So remove it as a needless TICKLESS dependency.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The system tick count is a 64 bit quantity that gets updated from
interrupt context, meaning that it's dangerously non-atomic and has to
be locked. The core kernel clock code did this right.
But the value was also exposed to the rest of the universe as a global
variable, and virtually nothing else was doing this correctly. Even
in the timer ISRs themselves, the interrupts may be themselves
preempted (most of our architectures support nested interrupts) by
code that wants to set timeouts and inspect system uptime.
Define a z_tick_{get,set}() API, eliminate the old variable, and make
sure everyone uses the right mechanism.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This was another "global variable" API. Give it function syntax too.
Also add a warning, because on nRF devices (at least) the cycle clock
runs in kHz and is too slow to give a precise answer here.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This just got turned into a function from a "variable" API, but
post-the-most-recent-patch it turns out to be degenerate anyway.
Everyone everywhere should always have been using the kconfig variable
directly, and it was only a weirdness in the tickless API that made it
confusing. Fix.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This was only used in a few places just to indirect the already
perfectly valid SYS_CLOCK_TICKS_PER_SEC value. There's no reason for
these to ever have been kconfig units, and in fact the distinction
appears to have introduced a hidden/untested bug in the power
subsystem (the two variables were used interchangably, but they were
defined in reciprocal units!).
Just use "ticks" as our time unit pervasively, and clarify the docs to
explain that.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The existing API defined sys_clock_{hw_cycles,ticks}_per_sec as simple
"variables" to be shared, except that they were only real storage in
certain modes (the HPET driver, basically) and everywhere else they
were a build constant.
Properly, these should be an API defined by the timer driver (who
controls those rates) and consumed by the clock subsystem. So give
them function syntax as a stepping stone to get there.
Note that this also removes the deprecated variable
_sys_clock_us_per_tick rather than give it the same treatment.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The kernel.h file had a bunch of internal APIs for timeout/clock
handling mixed in. Move these to sys_clock.h, which it always
included (in a weird location, so move THAT to kernel_includes.h with
everything else).
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Any word started with underscore followed by and uppercase letter or a
second underscore is a reserved word according with C99.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
On some architectures tick time cannot be expressed as integer
number of microseconds, introducing error in calculations using
sys_clock_us_per_tick variable.
This commit deprecates the sys_clock_us_per_tick variable and
replaces its usage by more precise calculations based on
sys_clock_hw_cycles_per_sec and sys_clock_ticks_per_sec.
Signed-off-by: Piotr Zięcik <piotr.ziecik@nordicsemi.no>
Adds event based scheduling logic to the kernel. Updates
management of timeouts, timers, idling etc. based on
time tracked at events rather than periodic ticks. Provides
interfaces for timers to announce and get next timer expiry
based on kernel scheduling decisions involving time slicing
of threads, timeouts and idling. Uses wall time units instead
of ticks in all scheduling activities.
The implementation involves changes in the following areas
1. Management of time in wall units like ms/us instead of ticks
The existing implementation already had an option to configure
number of ticks in a second. The new implementation builds on
top of that feature and provides option to set the size of the
scheduling granurality to mili seconds or micro seconds. This
allows most of the current implementation to be reused. Due to
this re-use and co-existence with tick based kernel, the names
of variables may contain the word "tick". However, in the
tickless kernel implementation, it represents the currently
configured time unit, which would be be mili seconds or
micro seconds. The APIs that take time as a parameter are not
impacted and they continue to pass time in mili seconds.
2. Timers would not be programmed in periodic mode
generating ticks. Instead they would be programmed in one
shot mode to generate events at the time the kernel scheduler
needs to gain control for its scheduling activities like
timers, timeouts, time slicing, idling etc.
3. The scheduler provides interfaces that the timer drivers
use to announce elapsed time and get the next time the scheduler
needs a timer event. It is possible that the scheduler may not
need another timer event, in which case the system would wait
for a non-timer event to wake it up if it is idling.
4. New APIs are defined to be implemented by timer drivers. Also
they need to handler timer events differently. These changes
have been done in the HPET timer driver. In future other timers
that support tickles kernel should implement these APIs as well.
These APIs are to re-program the timer, update and announce
elapsed time.
5. Philosopher and timer_api applications have been enabled to
test tickless kernel. Separate configuration files are created
which define the necessary CONFIG flags. Run these apps using
following command
make pristine && make BOARD=qemu_x86 CONF_FILE=prj_tickless.conf qemu
Jira: ZEP-339 ZEP-1946 ZEP-948
Change-Id: I7d950c31bf1ff929a9066fad42c2f0559a2e5983
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
Convert code to use u{8,16,32,64}_t and s{8,16,32,64}_t instead of C99
integer types. This handles the remaining includes and kernel, plus
touching up various points that we skipped because of include
dependancies. We also convert the PRI printf formatters in the arch
code over to normal formatters.
Jira: ZEP-2051
Change-Id: Iecbb12601a3ee4ea936fd7ddea37788a645b08b0
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
This is a start to move away from the C99 {u}int{8,16,32,64}_t types to
Zephyr defined u{8,16,32,64}_t and s{8,16,32,64}_t. This allows Zephyr
to define the sized types in a consistent manor across all the
architectures we support and not conflict with what various compilers
and libc might do with regards to the C99 types.
We introduce <zephyr/types.h> as part of this and have it include
<stdint.h> for now until we transition all the code away from the C99
types.
We go with u{8,16,32,64}_t and s{8,16,32,64}_t as there are some
existing variables defined u8 & u16 as well as to be consistent with
Zephyr naming conventions.
Jira: ZEP-2051
Change-Id: I451fed0623b029d65866622e478225dfab2c0ca8
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Replace the existing Apache 2.0 boilerplate header with an SPDX tag
throughout the zephyr code tree. This patch was generated via a
script run over the master branch.
Also updated doc/porting/application.rst that had a dependency on
line numbers in a literal include.
Manually updated subsys/logging/sys_log.c that had a malformed
header in the original file. Also cleanup several cases that already
had a SPDX tag and we either got a duplicate or missed updating.
Jira: ZEP-1457
Change-Id: I6131a1d4ee0e58f5b938300c2d2fc77d2e69572c
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
Also fixes up Kernel Primer examples to use these macros.
Change-Id: Ib1bc9e3f85ab75f81986bc3930fb287266a886b5
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
As for SECONDS() and MSEC, now sys_clock.h provides a USEC() macro.
Change-Id: I43e8b132d2deeb862d8cfda1f785115f339d6ddb
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Adds extern "C" { } blocks to header files so that they can be
safely used by C++ source files.
Change-Id: Ia4db0c36a5dac5d3de351184a297d2af0df64532
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
Removed old style file description and documnetation and apply
doxygen synatx.
Change-Id: I3ac9f06d4f574bf3c79c6f6044cec3a7e2f6e4c8
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Renames nanokernel global variable _nano_ticks to _sys_clock_tick_count.
Change-Id: I857407f1f7e8d9fd2eedc1c1696851173e58d2b4
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
Some timer devices, such as the HPET, read their frequencies at runtime.
All global constant values must be set at runtime in that case.
Change-Id: I408babce6deb857748a87691132d7e27e88f0bb8
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
Kumar Gala