Commit 3e729b2b1c ("kernel/timer: Correctly clamp period argument")
increased the lower limit to 1 so that it wouldn't conflict with a
K_NO_WAIT. But in doing so it enforced a minimum period of 2 ticks.
And the subtraction must obviously be avoided if the period is zero, etc.
Instead of doing this masquerade in k_timer_start(), let's move the
subtraction and clamping in z_timer_expiration_handler() right before
registering a new timeout. It makes the code cleaner, and then it is
possible to have single-tick periods again.
Whith this, timer_jitter_drift in tests/kernel/timer/timer_behavior does
pass with any CONFIG_SYS_CLOCK_TICKS_PER_SEC value, even when the tick
period is equal or larger than the specified timer period for the test
which failed the test before.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
When a timer is restarted from a high priority interrupt, it may
happen that the timer is re-added to the timeout list right after
it is removed from that list prior to execution of its expiration
handler but before that execution actually occurs. This leads to
an assertion failure reported for `z_add_timeout()` because then
that function, called from `z_timer_expiration_handler()` for
periodic timers, turns out to be adding a timeout that is already
added to the timeout list.
This commit detects such situation in `z_timer_expiration_handler()`
and makes that function exit immediately when that occurs (as the
timer was restared, its expiration handler should not be executed).
Signed-off-by: Andrzej Głąbek <andrzej.glabek@nordicsemi.no>
MISRA C:2012 Rule 14.4 (The controlling expression of an if statement
and the controlling expression of an iteration-statement shall have
essentially Boolean type.)
Use `bool' instead of `int' to represent Boolean values.
Use `do { ... } while (false)' instead of `do { ... } while (0)'.
Use comparisons with zero instead of implicitly testing integers.
This commit is a subset of the original commit:
5d02614e34a86b549c7707d3d9f0984bc3a5f22a
Signed-off-by: Simon Hein <SHein@baumer.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>
The k_timer utility was written to assume that the kernel timeout
handler would never be delayed by more than a tick, so it can naively
reschedule the next interrupt with a simple delay.
Unfortunately real platforms have glitchy hardware and high tick
rates, and on intel_adsp we're seeing this promise being broken in
some circumstances.
It's probably not a good idea to try to plumb the timer driver
interface up into the IPC layer to do this correction, but thankfully
the existing absolute timeout API provides the tools we need (though
it does require that CONFIG_TIMEOUT_64BIT be enabled).
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
For functions returning nothing, there is no need to document
with @return, as Doxgen complains about "documented empty
return type of ...".
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Add spinlock unlocking before calling timer expiration
handler. Locking was introduced by dde3d6c.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
before running timer's timeout function, we need to make
sure that those threads waiting on this timer have been
added into the timer's wait queue, so add operations to
use timer lock to mask interrupts in z_timer_expiration_handler
function to synchronize timer's wait queue.
Signed-off-by: Chen Peng1 <peng1.chen@intel.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>
Updated timer to not touch thread/scheduler code when multithreading
is off.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
Zephyr docs state that timers will act as one-shot timers when started
with a period of K_NO_WAIT or K_FOREVER. However the code adjusting
period was setting K_FOREVER timeout ticks to 1 which caused the timer
to expire every tick. This adds a check to not adjust K_FOREVER periods
Signed-off-by: Eric Johnson <eric@liveathos.com>
Several internal APIs wrote thread attributes (return value, mainly)
_after_ calling `z_ready_thread`. This is unsafe, at least in SMP,
because another core could have already picked up and run the thread.
Fixes#32800.
Signed-off-by: James Harris <james.harris@intel.com>
The internal API to measure time until a delay expires does not modify
the referenced timeout. Make the functions that call it take pointers
to const objects, so that they can be used with pointer to
const-qualified containers.
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
API that takes k_timer structures but doesn't change data in them is
updated to const-qualify the underlying object, allowing information
to be retrieved from contexts where the containing object is
immutable.
Signed-off-by: Peter A. Bigot <pab@pabigot.com>
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>
The possibility of passing K_FOREVER as the initial duration argument
to k_timer_start() wasn't being handled, with the result that the
computed value became an zero timeout (effecitvely treating it as
K_NO_WAIT and firing at the next tick).
This is obviously pathlogical, but it should still do what the code
says it should and wait forever.
Make k_timer_start(..., K_FOREVER, ...) a noop.
Fixes#25820
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The period argument of a k_timer needs an offset of one tick from the
value computed in user code (because periods get reset from within the
ISR, see the comment above this code for an explanation). When the
computed tick value was 1, it would become 0. This is actually
perfectly correct as a k_timeout_t to be passed to z_add_timeout().
BUT: to k_timer's API, K_NO_WAIT means "never" (i.e. the same as
K_FOREVER) and not "as soon as possible", so the period timer would
not be reset. This is sort of a wart, but it's the way the API has
been specified forever.
The upshot is that for the case of calling k_timer_start() with a
minimal period argument (i.e. one that produces "one tick"), the
period would be ignored and the timer would act like a one shot. Fix
the clamp so it can't produce K_NO_WAIT.
This also adds a filter for absolute timeouts, which (while that's
sort of a pathological usage) were getting that one tick offset when
it wasn't appropriate.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Add tick-based (i.e. precision resistant) inspection APIs for kernel
timeouts visible via k_timer, k_delayed work and thread timeouts
(i.e. pended/sleeping threads). These are each available in
"remaining" and "expires" variants returning time values relative to
current time and system start. All have system calls where applicable
(i.e. everywhere but k_delayed_work, which is not a userspace API)
The pre-existing millisecond "remaining_get()" predicates for timer
and delayed work remain, but are expressed in terms of the newer
calls.
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 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>
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>
