Commit Graph

16 Commits

Author SHA1 Message Date
Andrew Boie
71ce8ceb18 kernel: consolidate error handling code
* z_NanoFatalErrorHandler() is now moved to common kernel code
  and renamed z_fatal_error(). Arches dump arch-specific info
  before calling.
* z_SysFatalErrorHandler() is now moved to common kernel code
  and renamed k_sys_fatal_error_handler(). It is now much simpler;
  the default policy is simply to lock interrupts and halt the system.
  If an implementation of this function returns, then the currently
  running thread is aborted.
* New arch-specific APIs introduced:
  - z_arch_system_halt() simply powers off or halts the system.
* We now have a standard set of fatal exception reason codes,
  namespaced under K_ERR_*
* CONFIG_SIMPLE_FATAL_ERROR_HANDLER deleted
* LOG_PANIC() calls moved to k_sys_fatal_error_handler()

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-07-25 15:06:58 -07:00
Wentong Wu
5611e92347 kernel: add futex support
A k_futex is a lightweight mutual exclusion primitive designed
to minimize kernel involvement. Uncontended operation relies
only on atomic access to shared memory. k_futex structure lives
in application memory. And when using futexes, the majority of
the synchronization operations are performed in user mode. A
user-mode thread employs the futex wait system call only when
it is likely that the program has to block for a longer time
until the condition becomes true. When the condition comes true,
futex wake operation will be used to wake up one or more threads
waiting on that futex.

This patch implements two futex operations: k_futex_wait and
k_futex_wake. For k_futex_wait, the comparison with the expected
value, and starting to sleep are performed atomically to prevent
lost wake-ups. If different context changed futex's value after
the calling use-mode thread decided to block himself based on
the old value, the comparison will help observing the value
change and will not start to sleep. And for k_futex_wake, it
will wake at most num_waiters of the waiters that are sleeping
on that futex. But no guarantees are made on which threads are
woken, that means scheduling priority is not taken into
consideration.

Fixes: #14493.

Signed-off-by: Wentong Wu <wentong.wu@intel.com>
2019-06-24 15:38:21 -07:00
Anas Nashif
76d9d7806d x86: remove unused and x86 only latency benchmark
We do have a multi-architecture latency benchmark now, this one was x86
only, was never used or compiled in and is out-dated.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2019-06-03 09:42:00 -07:00
Anas Nashif
3ae52624ff license: cleanup: add SPDX Apache-2.0 license identifier
Update the files which contain no license information with the
'Apache-2.0' SPDX license identifier.  Many source files in the tree are
missing licensing information, which makes it harder for compliance
tools to determine the correct license.

By default all files without license information are under the default
license of Zephyr, which is Apache version 2.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2019-04-07 08:45:22 -04:00
Sebastian Bøe
1b86fb9da3 cmake: Use variables for target names
There is an effort underway to make most of the Zephyr build script's
reentrant. Meaning, the build scripts can be executed multiple times
during the same CMake invocation.

Reentrancy enables several use-cases, the motivating one is the
ability to build several Zephyr executables, or images, for instance a
bootloader and an application.

For build scripts to be reentrant they cannot be directly referencing
global variables, like target names, but must instead reference
variables, which can vary from entry to entry.

Therefore, in this patch, we replace global targets with variables.

Signed-off-by: Sebastian Bøe <sebastian.boe@nordicsemi.no>
2019-01-19 07:21:55 -05:00
Peter A. Bigot
bfad9721d2 kernel: remove k_alert API
This API was used in only one place in non-test code.  See whether we
can remove it.

Closes #12232

Signed-off-by: Peter A. Bigot <pab@pabigot.com>
2019-01-16 21:34:07 -05:00
Andy Ross
987c0e5fc1 kernel: New timeout implementation
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>
2018-10-16 15:03:10 -04:00
Adithya Baglody
8618716c68 kernel: Cmake: Add __ZEPHYR_SUPERVISOR__ macro for kernel files.
Normally a syscall would check the current privilege level and then
decide to go to _impl_<syscall> directly or go through a
_handler_<syscall>.
__ZEPHYR_SUPERVISOR__ is a compiler optimization flag which will
make all the system calls from the kernel files directly link
to the _impl_<syscall>. Thereby reducing the overhead of checking the
privileges.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2018-05-15 17:48:18 +03:00
Ramakrishna Pallala
f603e603bb lib: posix: Move posix layer from 'kernel' to 'lib'
Move posix layer from 'kernel' to 'lib' folder as it is not
a core kernel feature.

Fixed posix header file dependencies as part of the move and
also removed NEWLIBC related macros from posix headers.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
2018-04-05 16:43:05 -04:00
Youvedeep Singh
c8aa6570c1 kernel: POSIX: Compatibility layer for pthread APIs.
This patch provides pthread APIs for POSIX 1003.1 PSE52 standard.

Signed-off-by: Youvedeep Singh <youvedeep.singh@intel.com>
2018-02-21 19:17:28 -05:00
Andy Ross
364cbae412 kernel: Make irq_{un}lock() APIs into a global spinlock in SMP mode
In SMP mode, the idea of a single "IRQ lock" goes away.  Long term,
all usage needs to migrate to spinlocks (which become simple IRQ locks
in the uniprocessor case).  For the near term, we can ease the
migration (at the expense of performance) by providing a compatibility
implementation around a single global lock.

Note that one complication is that the older lock was recursive, while
spinlocks will deadlock if you try to lock them twice.  So we
implement a simple "count" semantic to handle multiple locks.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2018-02-16 10:44:29 -05:00
Anas Nashif
274ad46a84 kernel: move posix header to posix/
Having posix headers in the default include path causes issues with the
posix port. Move to a sub-directory to avoid any conflicts.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-12-27 14:16:08 -05:00
Youvedeep Singh
b4292cf35b kernel: posix: separating posix APIs according to their types.
Currently all posix APIs are put into single files (pthread.c).
This patch creates separate files for different API areas.

Signed-off-by: Youvedeep Singh <youvedeep.singh@intel.com>
2017-12-20 14:59:04 -05:00
Adithya Baglody
2fce4e4c9b kernel: userspace: Fixed the issue of handlers getting dropped by linker
The linker was always picking a weak handler over the actual one.
The linker always searches for the first definition of any function
weak or otherwise. When it finds this function it just links and
skips traversing through the full list.

In the context of userspace, we create the _handlers_ for each system
call in the respective file. And these _handlers_ would get linked to
a table defined in syscalls_dispatch.c. If for instance that this
handler is not defined then we link to a default error handler.

In the build procedure we create a library file from the kernel folder.
When creating this library file, we need to make sure that the file
syscalls_dispatch.c is the last to get linked(i.e userspace.c).
Because the table inside syscalls_dispatch.c would need all the
correct _handler_ definitions. If this is not handled then the system
call layer will not function correctly because of the linker feature.

Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
2017-12-14 09:07:23 -08:00
Anas Nashif
b893dac6b3 kernel: remove reference to legacy_timer.c in build system
We do not have this file anymore, remove it from the cmake files.

Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2017-12-09 08:48:51 -06:00
Sebastian Bøe
12f8f76165 Introduce cmake-based rewrite of KBuild
Introducing CMake is an important step in a larger effort to make
Zephyr easy to use for application developers working on different
platforms with different development environment needs.

Simplified, this change retains Kconfig as-is, and replaces all
Makefiles with CMakeLists.txt. The DSL-like Make language that KBuild
offers is replaced by a set of CMake extentions. These extentions have
either provided simple one-to-one translations of KBuild features or
introduced new concepts that replace KBuild concepts.

This is a breaking change for existing test infrastructure and build
scripts that are maintained out-of-tree. But for FW itself, no porting
should be necessary.

For users that just want to continue their work with minimal
disruption the following should suffice:

Install CMake 3.8.2+

Port any out-of-tree Makefiles to CMake.

Learn the absolute minimum about the new command line interface:

$ cd samples/hello_world
$ mkdir build && cd build
$ cmake -DBOARD=nrf52_pca10040 ..

$ cd build
$ make

PR: zephyrproject-rtos#4692
docs: http://docs.zephyrproject.org/getting_started/getting_started.html

Signed-off-by: Sebastian Boe <sebastian.boe@nordicsemi.no>
2017-11-08 20:00:22 -05:00