Also remove some old cflags referencing directories that do not exist
anymore.
Also replace references to legacy APIs in doxygen documentation of
various functions.
Change-Id: I8fce3d1fe0f4defc44e6eb0ae09a4863e33a39db
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
nano_cpu_idle/nano_cpu_atomic_idle were not ported to the unified
kernel, and only the old APIs were available. There was no real impact
since, in the unified kernel, only the idle thread should really be
doing power management. However, with a single-threaded kernel, these
functions can be useful again.
The kernel internals now make use of these APIs instead of the legacy
ones.
Change-Id: Ie8a6396ba378d3ddda27b8dd32fa4711bf53eb36
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
The way the ready thread cache was implemented caused it to not always
be "hot", i.e. there could be some misses, which happened when the
cached thread was taken out of the ready queue. When that happened, it
was not replaced immediately, since doing so could mean that the
replacement might not run because the flow could be interrupted and
another thread could take its place. This was the more conservative
approach that insured that moving a thread to the cache would never be
wasted.
However, this caused two problems:
1. The cache could not be refilled until another thread context-switched
in, since there was no thread in the cache to compare priorities
against.
2. Interrupt exit code would always have to call into C to find what
thread to run when the current thread was not coop and did not have the
scheduler locked. Furthermore, it was possible for this code path to
encounter a cold cache and then it had to find out what thread to run
the long way.
To fix this, filling the cache is now more aggressive, i.e. the next
thread to put in the cache is found even in the case the current cached
thread is context-switched out. This ensures the interrupt exit code is
much faster on the slow path. In addition, since finding the next thread
to run is now always "get it from the cache", which is a simple fetch
from memory (_kernel.ready_q.cache), there is no need to call the more
complex C code.
On the ARM FRDM K64F board, this improvement is seen:
Before:
1- Measure time to switch from ISR back to interrupted task
switching time is 215 tcs = 1791 nsec
2- Measure time from ISR to executing a different task (rescheduled)
switch time is 315 tcs = 2625 nsec
After:
1- Measure time to switch from ISR back to interrupted task
switching time is 130 tcs = 1083 nsec
2- Measure time from ISR to executing a different task (rescheduled)
switch time is 225 tcs = 1875 nsec
These are the most dramatic improvements, but most of the numbers
generated by the latency_measure test are improved.
Fixes ZEP-1401.
Change-Id: I2eaac147048b1ec71a93bd0a285e743a39533973
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
The Cortex-M3/4 kernel was reserving priorities 0 and 1 for itself, but
was not registering any exception on priority 0. Only reserve priority 0
and use it for SVC and fault exceptions instead of priority 1.
Change-Id: Iff2405e27fd4bed4e49ab90ec2ae984f2c0a83a6
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
Also remove NO_METRIC, which is not referenced anywhere anymore.
Change-Id: Ieaedf075af070a13aa3d975fee9b6b332203bfec
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
The ARM Cortex-M early boot was using a custom stack at the end of the
SRAM instead of the interrupt stack. This works as long as no static
data that needs a known initial value occupies that stack space. This
has probably not been an issue because the .noinit section is at the
very end of the image, but it was still wrong to use that region of
memory for that initial stack.
To be able to use the interrupt stack during early boot, the stack has
to be released before an interrupt can happen. Since ARM Cortex-M uses
PendSV as a very low priority exception for context switching, if a
device driver installs and enables an interrupt during the PRE_KERNEL
initialization points, an interrupt could take precedence over PendSV
while the initial dummy thread has not yet been context switched of and
thus released the interrupt stack. To address this, rather than using
_Swap() and thus triggering PendSV, the initialization logic switches to
the main stack and branches to _main() directly instead.
Fixes ZEP-1309
Change-Id: If0b62cc66470b45b601e63826b5b3306e6a25ae9
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
There was a possible race condition when setting the return value of a
thread that is pending, from an ISR.
A kernel function causes a thread to pend, with the following series of
steps:
- disable interrupts
- move current thread to wait_q
- call _Swap
Depending if running on M3/4 or M0+, _Swap will either issue a svc #0,
or pend PendSV directly. The same problem exists in both cases.
M3/4:
__svc will:
- enable interrupts
- trigger __pendsv
M0+:
_Swap() will enable interrupts.
__pendsv will:
- save register context including PSP into the thread struct
If an interrupt occurs between interrupts being enabled them and
__pendsv saving PSP, and the ISR sets the pending thread's return value,
this will happen:
- sees the thread in a wait_q
- removes it
- makes it ready
- calls _set_thread_return_value
- _set_thread_return_value looks at the thread's saved PSP to poke
the value
In this scenario, PSP hasn't yet been updated by __pendsv so it's a
stale value from the previous context switch, resulting in unpredictable
word on the stack getting set to the return value.
There is no way to fix this issue and still have the return value being
delivered directly in the pending thread's exception stack frame, in the
M0+ case. There will always be a window between the unlocking of
interrupts and PendSV being handled. On M3/4, it could be possible with
the mix of SVC and PendSV, since the exception stack frame is created in
the __svc handler. However, because we want to keep the two
implementations as close as possible, and there were talks of moving
M3/4 to using PendSV only, to save an exception, the approach taken
solves both cases.
The approach taken is similar to the ARC and Nios2 ports, where
there is a field in the thread structure that holds the return value.
_Swap() then loads r0/a1 with that value just before returning.
Fixes ZEP-1289.
Change-Id: Iee7e06fe3f8ded84aff918fd43408c7f589344d9
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
There was a lot of duplication between architectures for the definition
of threads and the "nanokernel" guts. These have been consolidated.
Now, a common file kernel/unified/include/kernel_structs.h holds the
common definitions. Architectures provide two files to complement it:
kernel_arch_data.h and kernel_arch_func.h. The first one contains at
least the struct _thread_arch and struct _kernel_arch data structures,
as well as the struct _callee_saved and struct _caller_saved register
layouts. The second file contains anything that needs what is provided
by the common stuff in kernel_structs.h. Those two files are only meant
to be included in kernel_structs.h in very specific locations.
The thread data structure has been separated into three major parts:
common struct _thread_base and struct k_thread, and arch-specific struct
_thread_arch. The first and third ones are included in the second.
The struct s_NANO data structure has been split into two: common struct
_kernel and arch-specific struct _kernel_arch. The latter is included in
the former.
Offsets files have also changed: nano_offsets.h has been renamed
kernel_offsets.h and is still included by the arch-specific offsets.c.
Also, since the thread and kernel data structures are now made of
sub-structures, offsets have to be added to make up the full offset.
Some of these additions have been consolidated in shorter symbols,
available from kernel/unified/include/offsets_short.h, which includes an
arch-specific offsets_arch_short.h. Most of the code include
offsets_short.h now instead of offsets.h.
Change-Id: I084645cb7e6db8db69aeaaf162963fe157045d5a
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
Symbols now use the K_ prefix which is now standard for the
unified kernel. Legacy support for these symbols is retained
to allow existing applications to build successfully.
Change-Id: I3ff12c96f729b535eecc940502892cbaa52526b6
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Adds standard prefix to symbolic option that flags a thread
as essential to system operation.
Change-Id: Ia904a81ce343fdd1cd44caaaeae641d822777f9b
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
They were the same, standardize on the lowercase one.
Change-Id: I8bca080e45f3e0970697d4451e468b9081f96f5f
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
Not disabling SysTick as it is optional by the spec.
SVC not used as there is no priority-based interrupt masking (only
PendSV is used).
Largely based on a previous work done by Euan Mutch <euan@abelon.com>.
Jira: ZEP-783
Change-Id: I38e29bfcf0624c1aea5f9fd7a74230faa1b59e8b
Signed-off-by: Ricardo Salveti <ricardo.salveti@linaro.org>
When adding a thread to the ready queue, it is often known at that time
if the thread added will be the next one to run or not. So, instead of
simply updating the ready queues and the bitmask, also cache what that
thread is, so that when the scheduler is invoked, it can simply fetch it
from there. This is only done if there is a thread in the cache, since
the way the cache is updated is by comparing the priorities of the
thread being added and the cached thread.
When a thread is removed from the ready queue, if it is currently the
cached thread, it is also removed from the cache. The cache is not
updated at this time, since this would be a preemptive fetching that
could be overriden before the newly cached thread would even be
scheduled in.
Finally, when a thread is scheduled in, it now becomes the cached thread
since the fact that it is running means that by definition it was the
next one to run.
Doing this can speed up considerably some context switch times,
especially when a thread is preempted by an interrupt and the same
thread is scheduled when the interrupt exits.
Change-Id: I6dc8391cfca566699bb9b217eafe6bc6a063c8bb
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
The '_timeout' structure is needed by dummy threads so that they can
handle timeouts.
Change-Id: Iefabd6ad93c8e176e95ce4262f5f3544dc90b7d5
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
The ARM architecture port is fitted with support for the unified kernel,
namely:
- the interrupt/exception exit code now pends PendSV if the current
thread is not a coop thread and if the scheduler is not locked
- fiber_abort is replaced by k_thread_abort(), which takes a thread ID
as a parameter (i.e. does not only operate on the current thread)
- the _nanokernel.flags cache of _current.flags is not used anymore
(could be a source of bugs) and is not needed in the scheduling algo
- there is no 'task' field in the _nanokernel anymore: PendSV not calls
_get_next_ready_thread instead
- the _nanokernel.fiber field is replaced by a more sophisticated
ready_q, based on the microkernel's priority-bitmap-based one
- thread initialization initializes new fields in the tcs, and does not
initialize obsolete ones
- nano_private includes nano_internal.h from the unified directory
- The FIBER, TASK and PREEMPTIBLE flags do not exist anymore: the thread
priority drives the behaviour
- the tcs uses a dlist for queuing in both ready and wait queues instead
of a custom singly-linked list
- other new fields in the tcs include a schedule-lock count, a
back-pointer to init data (when the task is static) and a pointer to
swap data, needed when a thread pending on _Swap() must be passed more
then just one value (e.g. k_stack_pop() needs an error code and data)
- the 'fiber' and 'task' fields of _nanokernel are replaced with an O(1)
ready queue (taken from the microkernel)
- fiberRtnValueSet() is aliased to _set_thread_return_value since it
also operates on preempt threads now
- _set_thread_return_value_with_data() sets the swap_data field in
addition to a return value from _Swap()
- convenience aliases are created for shorter names:
- _current is defined as _nanokernel.current
- _ready_q is defined as _nanokernel.ready_q
- _Swap() sets the threads's return code to -EAGAIN before swapping out
to prevent timeouts to have to set it (solves hard issues in some
kernel objects).
Change-Id: I36c03c362bc2908dae064ec67e6b8469fc573983
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
The comments for INT_ACTIVE and EXC_ACTIVE now refer to
"executing context ..." for all architectures.
Change-Id: Ib868958639a3b30e1814fcaa4d1f0651d3b2561e
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
Adds the preemptive floating point registers to the ARM's thread
control structure.
Change-Id: I65fbee6303091ce0658bbc442c4707d306b68e92
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
Adds a back pointer to the microkernel task to the TCS when
configured for a microkernel. This is a necessary prerequisite
to support microkernel tasks pending on nanokernel objects.
Change-Id: Ia62f9cf482ca20b008772dad80cbfd6acb6f5b7a
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
Changed names of Kconfig flags, variables, functions, files and
return codes consistent with names used in the RFC. Updated
relevant comments to match the changes.
Origin: Original
Change-Id: Ie7941032d7ad7af61fc02928f74538745e7966e8
Signed-off-by: Ramesh Thomas <ramesh.thomas@intel.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
The thread monitor allows to iterate over the thread context
structures for each existing thread (fiber/task) in the system.
Thread context structures do not expose thread entry information
directly. Although all the information can be scavenged from memory
stacks. Besides, accessing the information depends on the stack
implementation for each architecture.
By extending the tcs we allow a direct access to the thread
entry point and its parameters, only when thread monitor is
enabled.
It also allows a task to access its kernel task structure
through the first parameter of the thread.
This allows a debugger application to access the information directly
from the thread context structures list.
Change-Id: I0a435942b80eddffdf405016ac4056eb7aa1239c
Signed-off-by: Juan Manuel Cruz <juan.m.cruz.alcaraz@intel.com>
Fix an issue where, if a task is pending on a nano timeout, the duration
it wants to wait is not taken into account by the tickless idle code.
This could cause a system to wait forever, or to the limit of the timer
hardware (which is forever, for all intents and purposes).
This fix is to add one field in the nanokernel data structure for one
task to record the amount of ticks it will wait on a nano timeout. Only
one task has to be able to record this information, since, these waits
being looping busy waits, the task of highest priority is the only task
that can be actively waiting with a nano timeout. If a task of lower
priority was previously waiting, and a new task is now waiting, it means
that the wait of the original task has been interrupted, which will
cause said task to run the busy loop on the object again when it gets
scheduled, and the number of ticks it wants to wait has to be recomputed
and recorded again.
Change-Id: Ibcf0f288fc42d96897642cfee00ab7359716703f
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.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>
Saves an errno per-thread, retrieved via _get_errno(), instead of
changing the value of a global variable during context switches to avoid
a hit to the context switch performance.
Per-arch asm implementations are provided for maximum performance.
Enabled by default, but can be disabled via the CONFIG_ERRNO option.
Change-Id: I81d57a2e318c94c68eee913ae0d4ca3a3609c7a4
Signed-off-by: Benjamin Walsh <benjamin.walsh@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>
Software interrupts or system calls aren't really appropriate for
zephyr, but we have an ongoing need in our test code to run a
function with arguments synchronously in interrupt context.
This patch introduces irq_offload() which allows us to do this without
separate initialization or having to manage fake IRQs in the
interrupt controller.
ARM assembly code contributed by Benjamin Walsh
<benjamin.walsh@windriver.com>
ARC is not yet implemented but will be in a subsequent patch.
irq_test_common.h has been removed and all test cases updated to
use the new API.
Change-Id: I9af99ed31b62bc7eb340e32cf65e3d11354d1ec7
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
In order to have a name according to the functionality of the feature.
This commit rename any text, function and variable related with the
Profiler name to Event logger.
Change-Id: I4f612cbc7c37965c35a64f06cc3ce5e3249d90e5
Signed-off-by: Yonattan Louise <yonattan.a.louise.mendoza@intel.com>
The \NOMANUAL tag is a remnant from days of yore and is no longer
needed or useful. Cleaning up the code references to this.
Change-Id: I1b8cc9c9560d1dbb711f05fa63fd23386789875c
Signed-off-by: Dan Kalowsky <daniel.kalowsky@intel.com>
Change-Id: I6da43e41f9c6efee577b70513ec368ae3cce0144
Signed-off-by: Dan Kalowsky <daniel.kalowsky@intel.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Moving many of the functions from the old format of inline comments to
the newer doxygen format.
Change-Id: Ib0fe0d8627d7cd90219385a3ab627da8f9637d98
Signed-off-by: Dan Kalowsky <daniel.kalowsky@intel.com>
Change all the Intel and Wind River code license from BSD-3 to Apache 2.
Change-Id: Id8be2c1c161a06ea8a0b9f38e17660e11dbb384b
Signed-off-by: Javier B Perez Hernandez <javier.b.perez.hernandez@linux.intel.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
All supported platforms have descending stack (growth direction is
down). To avoid confusion just remove not needed stack direction
defines.
If new platform with stack direction up is added is should be
configured by adding Kconfig option eg STACK_GROWS_UP and
CONFIG_STACK_GROWS_UP should be used in code that depends on
stack growth direction.
Change-Id: I786ff1ab28d8f8bad3f6d1bbe64defc0e81d1707
Signed-off-by: Szymon Janc <ext.szymon.janc@tieto.com>
Add the interrupt profile points for x86 and ARM arquitectures. This
gives information regarding the time when interrupts occur.
Change-Id: Ic876c0e7f9e8819d53e0578416f09146f4456d3d
Signed-off-by: Yonattan Louise <yonattan.a.louise.mendoza@intel.com>
The term 'context' is vague and overloaded. Its usage for 'an execution
context' is now referred as such, in both comments and some APIs' names.
When the execution context can only be a fiber or a task (i.e. not an
ISR), it is referred to as a 'thread', again in comments and everywhere
in the code.
APIs that had their names changed:
- nano_context_id_t is now nano_thread_id_t
- context_self_get() is now sys_thread_self_get()
- context_type_get() is now sys_execution_context_type_get()
- context_custom_data_set/get() are now
sys_thread_custom_data_set/get()
The 'context' prefix namespace does not have to be reserved by the
kernel anymore.
The Context Control Structure (CCS) data structure is now the Thread
Control Structure (TCS):
- struct ccs is now struct tcs
- tCCS is now tTCS
Change-Id: I7526a76c5b01e7c86333078e2d2e77c9feef5364
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
There is no concept of a "process" in the system, so remove last
mentions of that concept from free-form text (doc, comments, macro
parameter names).
Change-Id: Ic1b73371c448ed93b0db46bc9bb412d1e1dbc8bd
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
Remove function name from comment and add @brief instead.
Also capitilize first letter.
Change-Id: Ib708b49bf02e5bc89b0066637a55874e659637e0
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Previous comment style used RETRURNS:, use @return to comply
with javadoc style.
Change-Id: Ib1dffd92da1d97d60063ec5309b08049828f6661
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
The change replaces multiple asterisks to ** at
the beginning of comments and adds a space before
the asterisks at the beginning of lines.
Change-Id: I7656bde3bf4d9a31e38941e43b580520432dabc1
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
The new name better reflects that this file contains all private
nanokernel APIs that are used by various kernel subsystems.
Change-Id: I4c258d582e93753eec9e575fdb5f9f2109417a0f
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
The new name better reflects that this file contains all private
microkernel APIs that are used by various kernel subsystems.
Change-Id: I5e52172a9e33aa130ce55ce59e887bba5c1c175a
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Makes name more consistent with other CPU_CORTEX_M* options.
Change-Id: I65968cb300207ba0de6231d9a67f2720be77b6ba
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
s_NANO contains the timeout queue, and each ccs needs a struct
_nano_timeout object that gets linked in the nanokernel timeout queue.
Change-Id: Iad027eaaebcffe190e95f0b9d068f047062559c2
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
Anas Nashif