Timers are based off timeouts now, which can only be enabled when the
system clock is enabled. So the three are really just one setting now.
Keep the NANO_TIMERS and NANO_TIMEOUTS around for now until all
middleware that rely on them is updated. They are always enabled when
SYS_CLOCK_EXISTS is enabled.
Change-Id: Iaef1302ef9ad8fc5640542ab6d7304d67aafcfdc
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
Rename remaining functions to fit with kernel naming convention for
internal interfaces. Use struct k_thread instead of struct tcs.
Change-Id: I28cd7f6f4d7ddaeb825c8d2999242d8d2dd93f31
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
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>
Simple conversion from ticks for now.
Change-Id: Ib81fc738d45641a6a3a88d2adec1f3eb861f3f97
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
The routine _nano_get_earliest_deadline() is still used by both
the microkernel and nanokernel.
Change-Id: I14501e6d41ca5faac27dead5873ef897e79831aa
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
Replaces _nano_get_earlist_deadline() with the more streamlined
routine _timeout_get_next_expiry().
Change-Id: Iee7ec727f0500cb28e37a364036fd40a483b40c3
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
Summary of what this includes:
initialization:
Copy from nano_init.c, with the following changes:
- the main thread is the continuation of the init thread, but an idle
thread is created as well
- _main() initializes threads in groups and starts the EXE group
- the ready queues are initialized
- the main thread is marked as non-essential once the system init is
done
- a weak main() symbol is provided if the application does not provide a
main() function
scheduler:
Not an exhaustive list, but basically provide primitives for:
- adding/removing a thread to/from a wait queue
- adding/removing a thread to/from the ready queue
- marking thread as ready
- locking/unlocking the scheduler
- instead of locking interrupts
- getting/setting thread priority
- checking what state (coop/preempt) a thread is currenlty running in
- rescheduling threads
- finding what thread is the next to run
- yielding/sleeping/aborting sleep
- finding the current thread
threads:
- Add operationns on threads, such as creating and starting them.
standardized handling of kernel object return codes:
- Kernel objects now cause _Swap() to return the following values:
0 => operation successful
-EAGAIN => operation timed out
-Exxxxx => operation failed for another reason
- The thread's swap_data field can be used to return any additional
information required to complete the operation, such as the actual
result of a successful operation.
timeouts:
- same as nano timeouts, renamed to simply 'timeouts'
- the kernel is still tick-based, but objects take timeout values in
ms for forward compatibility with a tickless kernel.
semaphores:
- Port of the nanokernel semaphores, which have the same basic behaviour
as the microkernel ones. Semaphore groups are not yet implemented.
- These semaphores are enhanced in that they accept an initial count and a
count limit. This allows configuring them as binary semaphores, and also
provisioning them without having to "give" the semaphore multiple times
before using them.
mutexes:
- Straight port of the microkernel mutexes. An init function is added to
allow defining them at runtime.
pipes:
- straight port
timers:
- amalgamation of nano and micro timers, with all functionalities
intact.
events:
- re-implementation, using semaphores and workqueues.
mailboxes:
- straight port
message queues:
- straight port of microkernel FIFOs
memory maps:
- straight port
workqueues:
- Basically, have all APIs follow the k_ naming rule, and use the _timeout
subsystem from the unified kernel directory, and not the _nano_timeout
one.
stacks:
- Port of the nanokernel stacks. They can now have multiple threads
pending on them and threads can wait with a timeout.
LIFOs:
- Straight port of the nanokernel LIFOs.
FIFOs:
- Straight port of the nanokernel FIFOs.
Work by: Dmitriy Korovkin <dmitriy.korovkin@windriver.com>
Peter Mitsis <peter.mitsis@windriver.com>
Allan Stephens <allan.stephens@windriver.com>
Benjamin Walsh <benjamin.walsh@windriver.com>
Change-Id: Id3cadb3694484ab2ca467889cfb029be3cd3a7d6
Signed-off-by: Benjamin Walsh <benjamin.walsh@windriver.com>
Andrew Boie