Add the special thread queue name _Thread_queue_Object_name to mark
thread queues embedded in an object with identifier. Using the special
thread state STATES_THREAD_QUEUE_WITH_IDENTIFIER is not reliable for
this purpose since the thread wait information and thread state are
protected by different SMP locks in separate critical sections. Remove
STATES_THREAD_QUEUE_WITH_IDENTIFIER.
Add and use _Thread_queue_Object_initialize().
Update #2858.
Add POSIX shared memory manager (Shm). Includes a hook-based
approach for the backing memory storage that defaults to the
Workspace, and a test is provided using the heap. A test is
also provided for the basic use of mmap'ing a shared memory
object. This test currently fails at the mmap stage due to
no support for mmap.
Replace STATES_DELAYING with STATES_WAITING_FOR_TIME.
There is no need for separate timeout thread states. The
Thread_Control::Timer::header and Watchdog_Control::cpu members can be
used to figure out the kind of timeout.
The fatal is internal indicator is redundant since the fatal source and
error code uniquely identify a fatal error. Keep the fatal user
extension is internal parameter for backward compatibility and set it to
false always.
Update #2825.
Initialize thread queue context early preferably outside the critical
section.
Remove implicit _Thread_queue_Context_initialize() from
_Thread_Wait_acquire().
Move thread state for _Thread_queue_Enqueue() to the thread queue
context. This reduces the parameter count of _Thread_queue_Enqueue()
from five to four (ARM for example has only four function parameter
registers). Since the thread state is used after several function calls
inside _Thread_queue_Enqueue() this parameter was saved on the stack
previously.
Turn pthread_spinlock_t into a self-contained object. On uni-processor
configurations, interrupts are disabled in the lock/trylock operations
and the previous interrupt status is restored in the corresponding
unlock operations. On SMP configurations, a ticket lock is a acquired
and released in addition.
The self-contained pthread_spinlock_t object is defined by Newlib in
<sys/_pthreadtypes.h>.
typedef struct {
struct _Ticket_lock_Control _lock;
__uint32_t _interrupt_state;
} pthread_spinlock_t;
This implementation is simple and efficient. However, this test case of
the Linux Test Project would fail due to call of printf() and sleep()
during spin lock ownership:
https://github.com/linux-test-project/ltp/blob/master/testcases/open_posix_testsuite/conformance/interfaces/pthread_spin_lock/1-2.c
There is only limited support for profiling on SMP configurations.
Delete CORE spinlock implementation.
Update #2674.
Replace the expected thread dispatch disable level with a thread queue
enqueue callout. This enables the use of _Thread_Dispatch_direct() in
the thread queue enqueue procedure. This avoids impossible exection
paths, e.g. Per_CPU_Control::dispatch_necessary is always true.
This function is useful for operations which synchronously block, e.g.
self restart, self deletion, yield, sleep. It helps to detect if these
operations are called in the wrong context. Since the thread dispatch
necessary indicator is not used, this is more robust in some SMP
situations.
Update #2751.
Add priority nodes which contribute to the overall thread priority.
The actual priority of a thread is now an aggregation of priority nodes.
The thread priority aggregation for the home scheduler instance of a
thread consists of at least one priority node, which is normally the
real priority of the thread. The locking protocols (e.g. priority
ceiling and priority inheritance), rate-monotonic period objects and the
POSIX sporadic server add, change and remove priority nodes.
A thread changes its priority now immediately, e.g. priority changes are
not deferred until the thread releases its last resource.
Replace the _Thread_Change_priority() function with
* _Thread_Priority_perform_actions(),
* _Thread_Priority_add(),
* _Thread_Priority_remove(),
* _Thread_Priority_change(), and
* _Thread_Priority_update().
Update #2412.
Update #2556.
Introduce Thread_queue_Lock_context to contain the context necessary for
thread queue lock and thread wait lock acquire/release operations to
reduce the Thread_Control size.
The _Thread_Lock_acquire() function had a potentially infinite run-time
due to the lack of fairness at atomic operations level.
Update #2412.
Update #2556.
Update #2765.
* Fixes a bug with elapsed time calculations misusing absolute time
arguments in nanosleep_helper by passing the requested relative interval.
* Fixes a bug with truncation of absolute timeouts by passing the
full 64-bit value to Thread_queue_Enqueue.
* Share yield logic between nanosleep and clock_nanosleep.
updates #2732
Sleeping with CLOCK_REALTIME should use the WATCHDOG_ABSOLUTE
clock discipline for the threadq so that the timeout interval
may change in case the clock source changes. Similarly,
CLOCK_MONOTONIC uses the WATCHDOG_RELATIVE threadq that will
only wakeup the thread after the requested count of ticks elapse.
updates #2732
