Since the per-CPU SMP lock must be acquired and released to send the
message a single interrupt broadcast operations offers no benefits. If
synchronization is required, then a SMP barrier must be used anyway.
Merge RTEMS_FATAL_SOURCE_BSP_GENERIC and RTEMS_FATAL_SOURCE_BSP_SPECIFIC
into new fatal source RTEMS_FATAL_SOURCE_BSP. This makes it easier to
figure out the code position given a fatal source and code.
Add a CPU counter interface to allow access to a free-running counter.
It is useful to measure short time intervals. This can be used for
example to enable profiling of critical low-level functions.
Add two busy wait functions rtems_counter_delay_ticks() and
rtems_counter_delay_nanoseconds() implemented via the CPU counter.
Install inter-processor interrupt (IPI) handler before secondary CPUs
are started. This ensures that secondary CPUs fetch the newly installed
handler.
Remove superfluous return statement.
Add and use _SMP_Get_current_processor() and
rtems_smp_get_current_processor().
Delete bsp_smp_interrupt_cpu().
Change type of current processor index from int to uint32_t to match
_SMP_Processor_count type.
Rename in rtems_smp_get_processor_count(). Always provide
<rtems/score/smp.h> and <rtems/rtems/smp.h>. Add
_SMP_Get_processor_count(). This function will be a compile time
constant defined to be one on uni-processor configurations. This allows
iterations over all processors without overhead on uni-processor
configurations.
Delete bsp_smp_wait_for(). Other parts of the system work without
timeout, e.g. the spinlocks. Using a timeout here does not make the
system more robust.
Delete bsp_smp_cpu_state and replace it with Per_CPU_State. The
Per_CPU_State follows the Score naming conventions. Add
_Per_CPU_Change_state() and _Per_CPU_Wait_for_state() functions to
change and observe states.
Use Per_CPU_State in Per_CPU_Control instead of the anonymous integer.
Add _CPU_Processor_event_broadcast() and _CPU_Processor_event_receive()
functions provided by the CPU port. Use these functions in
_Per_CPU_Change_state() and _Per_CPU_Wait_for_state().
Add prototype for _SMP_Send_message().
Delete RTEMS_BSP_SMP_FIRST_TASK message. The first context switch is
now performed in rtems_smp_secondary_cpu_initialize(). Issuing the
first context switch in the context of the inter-processor interrupt is
not possible on systems with a modern interrupt controller. Such an
interrupt controler usually requires a handshake protocol with interrupt
acknowledge and end of interrupt signals. A direct context switch in an
interrupt handler circumvents the interrupt processing epilogue and may
leave the system in an inconsistent state.
Release lock in rtems_smp_process_interrupt() even if no message was
delivered. This prevents deadlock of the system.
Simplify and format _SMP_Send_message(),
_SMP_Request_other_cores_to_perform_first_context_switch(),
_SMP_Request_other_cores_to_dispatch() and
_SMP_Request_other_cores_to_shutdown().
Do not call bsp_smp_secondary_cpu_initialize() in
rtems_smp_secondary_cpu_initialize(). This allows more flexibilty in
the BSP low-level code. Specify context requirements for a call to
rtems_smp_secondary_cpu_initialize().
