Call to osThreadTerminate is guarded by local_id check, to avoid parameter error fault when deleting or terminating Thread object that was not started.
armcc fopen allocated a mutex using the retargeted system-level
_mutex_initialize function. Interestingly, malloc also uses this
same _mutex_initialization function, which prevents a full solution
relying on malloc. The solution previously implemented involved using
the rtx mutex pool for the first 8 mutexes, then falling back on
malloc.
The previous implementation relied on osMutexNew returning an error
on out-of-memory. An unrelated change causes osMutexNew to instead
assert (except for release mode). This meant if you exceed 8 system-
level mutexes in armcc you will hit an assert. Since the filesystem
code can call fopen an unlimited number of times, this is a problem.
Solution is to keep track of which static mutexes we've allocated, so
we know before calling osMutexNew if we need to call malloc.
Also _mutex_free never deallocated the malloced mutexes, which would
cause fopen to leak memory.
Various RTOS classes were storing their CMSIS-RTOS creation attribute
structure as a member, when it's not required after construction. Reduce
memory by eliminating this member.
uVisor doesn't set the PSP of the target thread. The RTOS sets the PSP
of the target thread from the target thread's TCB. However, when
interrupts of higher priority than PendSV happen between the call to
uVisor to switch boxes, and the RTOS setting PSP, the uVisor vIRQ
interrupt handler will attempt to use an invalid PSP (the PSP from
before the box and thread switch). This leads to a crash. Make box and
thread switching atomic by disabling interrupts immediately before the
box switching until immediately after the new PSP is set.
OsEventObserver objects expect a context to be maintained per thread on
their behalf. Add this context to the thread control block and extend
the thread creation functions with the ability to supply a context.
Add the OsEventObserver mechanism. A client interested in receiving
notifications on certain OS events can register to receive notifications
with osRegisterForOsEvents. This is useful for clients like the secure
memory allocator, which observes thread switching events in order to
swap in and out different memory allocator objects.
mbed OS used older RTX4 version and with osThreadDef accepting only 3
parameters, to preserve compatibility we hardcode the 'instances'
parameter to 1.
Ensure both the stack and stack size used in the Thread class are
aligned to 8 bytes. This prevents the runtime error
"Thread 0 error -11: Unknown" due to incorrect stack alignment.
The current mbed-os drivers rely on a tickrate of 1ms for timing.
This means that if OS_TICK_FREQ is set to any value other than 1000
then mbed-os driver will no longer delay for the correct amount of
time. To prevent this from happening this patch triggers a compile
time error if a tickrate other than 1m is used.