z_add_timeout returns without any effect if timeout is equal to K_FOREVER
so there is no need to guard its timeout parameter from a K_FOREVER.
Signed-off-by: Emil Hammarström <emil.a.hammarstrom@gmail.com>
Some private symbol names were widely duplicated throughout the kernel
such as lock and handle_poll_event. This arguably made the kernel less
readable as the locality of the name lock is highly confusing.
Rename all compilation unit locks to match their usage (e.g.
mutex_lock). Improving readability.
Furthermore, by deduplicating these symbols we enable potential
amalgamation builds of the kernel where all C files are merged
into one large C file or compliation unit allowing for better
compiler visibility and optimization.
Signed-off-by: Tom Burdick <thomas.burdick@infineon.com>
triggered_work_expiration_handler and signal_triggered_work /
triggered_work_cancel both want to take a k_work_poll item from
"waiting on event" to "submitted to work queue". Pre-1b8c7a3 the
dticks-cancel check in the handler made it bail when the cancel
side had aborted the timeout; without it, the in-flight handler
could submit the work twice and overwrite poll_result.
Use poller.is_polling as the wake-ownership flag. signal_poll_event
already clears it after a successful signal; the migration makes
signal_triggered_work() and triggered_work_cancel() clear it BEFORE
the abort, and adds a check at handler entry so the loser bails.
All under poll.c::lock, so the flip is atomic between the three
sides.
z_abort_timeout() is replaced by a best-effort (void)
z_try_abort_timeout() at the signal_triggered_work site -- a racing
in-flight handler observes is_polling=false and returns without
doing work.
triggered_work_cancel() additionally waits for any in-flight handler
to fully complete before returning success. This closes a pre-existing
UAF window: when cancel returned 0, the handler could still be about
to run (blocked on poll.c::lock while we held it), and would
dereference work->poller.is_polling after the caller released the
lock. If a user-space caller freed `work` between k_work_poll_cancel()
returning and the handler bailing, the read raced with the free. The
same wait also serializes against k_work_poll_submit_to_queue()
re-arming the same `work` for a new poll: without it, the old
handler could unblock after the re-arm flipped is_polling back to
true and erroneously act on the new setup.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
kernel.h implies kernel_structs.h via kernel_includes.h, making
explicit inclusion of kernel_structs.h unnecessary whenever kernel.h
is already included in the same translation unit.
Remove the redundant includes across arch, boards, drivers, kernel,
lib, samples, subsys, and tests trees.
in include/zephyr/kernel_structs.h:
* 2. kernel.h shall imply kernel_structs.h, such that it shall not be
* necessary to include kernel_structs.h explicitly when kernel.h is
* included.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Reworks the K_OOPS(K_SYSCALL_OBJ(...)) logic in z_vrfy_k_poll()
to ensure that the allocated 'events_copy' is freed before the
K_OOPS() is performed.
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
This fixes a subtle race condition in the poll timeout expiration
handler triggered_work_expiration_handler(). There was a small
window of opportunity between when sys_clock_announce() unlocks
interrupts and that the handler re-locked them that one or more
higher priority interrupts (or threads running on another CPU)
could abort the poll's timeout.
As each place where the timeout could be added or aborted already
locked the poll.c::lock spinlock, this commit updates the handler
to lock that spinlock upon entry and bail early if the timeout
has been detected to have been canceled.
It also changes the handler's call to k_work_submit_to_queue() to
z_work_submit_to_queue() since it is known that it will not be
rescheduling at that point within the timer ISR.
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
In z_vrfy_k_poll, there is a memory access check
K_SYSCALL_MEMORY_WRITE which is wrapped in a spinlock, the same
spinlock used in z_handle_obj_poll_events which is called from
k_sem_give() for example.
The K_SYSCALL_MEMORY_WRITE() macro conditionally calls LOG_ERR()
which may call the UART console, which may call an API like
k_sem_give(). This will cause a deadlock since the locked spinlock
will be relocked, and a recursive lock if SPINLOCK_VALIDATE and
ASSERTS are enabled as the validation will fail, causing a LOG_ERR,
causing a k_sem_give() causing a relock... until stack overflows.
To solve the issue, only protect the copy of events to events_copy
with the spinlock, the content of events is not actually checked, and
bound is not shared, so there is no need to do this validation in a
critical section. The contents of events is shared so that must be
copied in atomically.
Signed-off-by: Bjarki Arge Andreasen <bjarki.andreasen@nordicsemi.no>
Two issues:
- is_condition_met() was missing proper code for The
K_POLL_TYPE_PIPE_DATA_AVAILABLE case
- z_handle_obj_poll_events() was misplaced in z_impl_k_pipe_write()
Note: I added support for the deprecated pipe implementation to
is_condition_met() but that is untested.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Changes the return type of z_handle_obj_poll_events() so that it
returns true if there were polling events to handle (false
otherwise).
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
Change:
commit cc6317d7ac
Author: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Date: Fri Nov 1 14:03:32 2019 +0200
kernel: poll: Allow 0 event input
Allows `k_poll` to be user with 0 events, which is useful for allowing just
a sleep without having to create artificial events.
Allow the same for `k_work_submit_to_queue()` and `k_work_submit()`.
Signed-off-by: David Brown <david.brown@linaro.org>
This commit adds polling support to the newly rewritten k_pipe interface.
Changes include:
* Removed ifdef CONFIG_POLL from kernel/poll.c to let both implementations
coexist.
* Added the needed datastructures to the new k_pipe struct.
* k_pipe_write(..) now notifies the poll subsystem that data is available.
Signed-off-by: Måns Ansgariusson <Mansgariusson@gmail.com>
Mostly a revert of commit b1def7145f ("arch: deprecate `_current`").
This commit was part of PR #80716 whose initial purpose was about providing
an architecture specific optimization for _current. The actual deprecation
was sneaked in later on without proper discussion.
The Zephyr core always used _current before and that was fine. It is quite
prevalent as well and the alternative is proving rather verbose.
Furthermore, as a concept, the "current thread" is not something that is
necessarily architecture specific. Therefore the primary abstraction
should not carry the arch_ prefix.
Hence this revert.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
`_current` is now functionally equals to `arch_curr_thread()`, remove
its usage in-tree and deprecate it instead of removing it outright,
as it has been with us since forever.
Signed-off-by: Yong Cong Sin <ycsin@meta.com>
Signed-off-by: Yong Cong Sin <yongcong.sin@gmail.com>
Namespaced the generated headers with `zephyr` to prevent
potential conflict with other headers.
Introduce a temporary Kconfig `LEGACY_GENERATED_INCLUDE_PATH`
that is enabled by default. This allows the developers to
continue the use of the old include paths for the time being
until it is deprecated and eventually removed. The Kconfig will
generate a build-time warning message, similar to the
`CONFIG_TIMER_RANDOM_GENERATOR`.
Updated the includes path of in-tree sources accordingly.
Most of the changes here are scripted, check the PR for more
info.
Signed-off-by: Yong Cong Sin <ycsin@meta.com>
Add a closing comment to the endif with the configuration
information to which the endif belongs too.
To make the code more clearer if the configs need adaptions.
Signed-off-by: Simon Hein <Shein@baumer.com>
Move the syscall_handler.h header, used internally only to a dedicated
internal folder that should not be used outside of Zephyr.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
The signal_poll_event function was previously called without the poll
lock held. This created a race condition between a thread calling k_poll
to wait for an event and another thread signalling for this same event.
This resulted in the waiting thread to stay pending and the handle to it
getting removed from the notifyq, meaning it couldn't get woken up
again.
Signed-off-by: Ambroise Vincent <ambroise.vincent@arm.com>
The _EXPIRED macro is no longer necessary. It is a relic of an older
timeout processing algorithm from several years ago.
Signed-off-by: Peter Mitsis <peter.mitsis@intel.com>
This header does not expose any public APIs, so move it under
kernel/include and change files including it.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
k_poll does not currently allow polling on pipes. This adds support
for doing so on buffered pipes.
Signed-off-by: Jeremy Herbert <jeremy.006@gmail.com>
This adds the internal function z_work_submit_to_queue(), which
submits the work item to the queue but doesn't force the thread to yield,
compared to the public function k_work_submit_to_queue().
When called from poll.c in the context of k_work_poll events, it ensures
that the thread does not yield in the context of the spinlock of object
that became available.
Fixes#45267
Signed-off-by: Lucas Dietrich <ld.adecy@gmail.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>
Removing the 'U' to avoid the type of num_events changed.
And make sure it is meaningful Z_SYSCALL_VERIFY micro.
Fixed#40614
Signed-off-by: NingX Zhao <ningx.zhao@intel.com>
The final else {} in the if...else if is missing required
comment (non-empty, ';' is not sufficient). This adds a comment
to comply with CG 15.7.
Signed-off-by: Jennifer Williams <jennifer.m.williams@intel.com>
Add Poll API and Work Poll tracing, default hooks, and documentation.
Signed-off-by: Torbjörn Leksell <torbjorn.leksell@percepio.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
register_events() and signal_poll_event() missing final
else statement in the if else if construct. This commit adds
else {} to comply with coding guideline 15.7.
Signed-off-by: Jennifer Williams <jennifer.m.williams@intel.com>
This commit adds the ability to use a message queue as a
k_poll object. It follows the same pattern as polling on
FIFOs.
This change has been proven in practice at Samsara.
Fixes: #26728
Signed-off-by: Nick Graves <nicholas.graves@samsara.com>
Tests of a value against zero should be made explicit, unless the
operand is effectively Boolean. This is based on MISRA rule 14.4.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Add a 'U' suffix to values when computing and comparing against
unsigned variables and other related fixes of the same MISRA rule (10.4)
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
This symbol is reserved and usage of reserved symbols violates the
coding guidelines. (MISRA 21.2)
NAME
signal - ANSI C signal handling
SYNOPSIS
#include <signal.h>
sighandler_t signal(int signum, sighandler_t handler);
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
This symbol is reserved and usage of reserved symbols violates the
coding guidelines. (MISRA 21.2)
NAME
remove - remove a file or directory
SYNOPSIS
#include <stdio.h>
int remove(const char *pathname);
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
`z_is_t1_higher_prio_than_t2` was being called twice in both the
context-switch fastpath and in `z_priq_rb_lessthan`, just to
dealing with priority ties. In addition, the API was error-prone
(and too much in the fastpath to be able to assert its invarients)
- see also #32710 for a previous example of this API breaking
and returning a>b but also b>a.
Replacing this with a direct 3-way comparison `z_cmp_t1_prio_with_t2`
sidesteps most of these issues. There is still a concern that
`sgn(z_cmp_t1_prio_with_t2(a,b)) != -sgn(z_cmp_t1_prio_with_t2(b,a))`
but I don't see any way to alleviate this aside from adding an
assert to the fastpath.
Signed-off-by: James Harris <james.harris@intel.com>
The poll code uses a dummy wait queue so the threads have something to
block on, but the previous coherence pass (which rearranged things to
put the _poller data elsewhere) missed that this was on the stack,
which is not allowed. It actually has no use except as a list, so
make it a global static instead.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
register_event always returns 0, so the conditional will
always take the first branch and code in the else part
is never reached.
Fixes#31282
Signed-off-by: Ningx Zhao <ningx.zhao@intel.com>
This legacy struct still had a non-standard name. Clean it up to
conform to currrent naming guidelines.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Fix the issue where the kernel poll code would place the tracking
struct on the caller stack and share it with other threads, thus
creating a cache coherence issue on systems where KERNEL_COHERENCE is
enabled.
This works by eliminating the thread backpointer in struct _poller and
simply placing the (now just two-byte!) struct directly into the
thread struct.
Note that this doesn't attempt to fix the API paradigm that the
natural way to structure a call to k_poll() is to use an array of
k_poll_events on the CALLER's stack. So it's likely that most
"typical" k_poll code is still going to have problems with
KERNEL_COHERENCE. But at least now the kernel internals aren't
fundamentally broken.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The poll code was playing this weird trick where the thread pointer in
the "struct _poller" object for a triggered work item. It would not
be a thread to wake up, but instead a pointer to the (non-polling)
thread operated by the work queue being triggered. The code would
never touch this thread, just use it as a way to get a pointer to the
enclosing work queue struct.
Just store the work queue pointer in the first place. It's much
simpler, and makes future modifications to remove that thread pointer
possible.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The triggered work scheme uses a trick where it overloads the thread
pointer field of the struct poller (which normally stores the ID of
the thread that is blocked in k_poll()) to be able to find the work
queue to which it will submit.
Give it its own pointer field to break this false dependency.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Somewhat weirdly, k_poll() can do one of two things when the set of
events is signaled: it can wake up a sleeping thread, or it can submit
an unrelated work item to a work queue. The difference in behaviors
is currently captured by a callback, but as there are only two it's
cleaner to put this into a "mode" enumerant. That also shrinks the
size of the data such that the poller struct can be moved somewhere
other than the calling stack.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
The k_poll implementation places a struct _poller on the stack and
shares it with other threads, which is incompatible with the
KERNEL_COHERENCE model of cached stacks.
Make this a hard build failure instead of a kconfig dependency for
clarity. The failures if a user actually enables both are subtle and
difficult to debug.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Both operands of an operator in the arithmetic conversions
performed shall have the same essential type category.
Changes are related to converting the integer constants to the
unsigned integer constants
Signed-off-by: Aastha Grover <aastha.grover@intel.com>
