The events are emitted when we enter the scheduler with the non-blocking
flag, which is usually the case when using the nosv_yield and
nosv_schedpoint API functions.
See: https://gitlab.bsc.es/nos-v/nos-v/-/merge_requests/155
The nosv.can_breakdown attribute states if enough events for the
breakdown model of nOS-V are enabled at runtime. It is used to ensure
that breakdown traces have the progress events enabled along with others
required for proper visualization of traces.
The emulator will panic when the level is not enough, instead of relying
on users to always remember to enable the correct level.
It will appear when the emulator knows that a thread is running in the
CPU, but no subsystem has been entered yet. This is common a
instrumentation level lower than 3 in nOS-V.
The nOS-V events are modified in two ways: 1) to create a parallel task
the new VTC event must be used and 2) all task events for both normal
(VTc) and parallel (VTC) tasks require an extra argument in the payload
to indicate the body id. As a consequence, the nOS-V model version is
now increased to 2.0.0.
Additionally, all the channel PRV flags are set to PRV_SKIPDUPNULL, so
duplicates are only emitted if they are not null. It solves the problem
when a task switches to another task with the same body id.
A new Paraver configuration is added for the body id.
Instead of showing the "attached" state with the VH{aA} events, we show
when the call to nosv_attach() and nosv_detach() take place. The old
VH{aA} events are now ignored. Bumps the nOS-V model version to 1.1.0.
Implements a small language parser to define the emulator events. The
event specification is parsed at emulation (when the emulator runs).
The ovnidump output now prints the events with the arguments formatted
as given in the event description.
It also introduces some consistency checks over the event MCVs, which
must begin with the model identifier and cannot be duplicated.
Until now, emulation models were always being registered via probe(),
which causes the emulator to initialize all the channels. To reduce the
overhead, the channels were not connected or registered in the bay
until the first event of that model was received. This delayed connect
was causing issues in muxes where the newly connected model required
refreshing the touched channels. Which in turn was causing unexpected
PRV events.
By determining which models we need to enable, we can remove the delayed
connect mechanism and just enable those models at initialization time,
and connect the channels.
When running without all the subsystem events enabled in nOS-V, it is
possible to emit two consecutive VTx events, which would push twice the
same value ST_TASK_BODY into the subsystem channel. This change relaxes
the subsystem channel to accept duplicate stacked values. A regression
test is also added.
Reported-By: Raúl Peñacoba Veigas <raul.penacoba@bsc.es>
In nOS-V, when a task was paused via the VTp event, two things were
happening: 1) the task state was set to pause and 2) the subsystem state
"Task: Running" was being popped.
This causes a problem when a task calls nosv_submit() in blocking mode,
as it will call nosv_pause() which will emit a VTp event from a
subsystem different than "Task: Running".
To solve this conflict, we handle the subsystems state and the task
state separately with the VTp and VTr events. The subsystem state "Task:
Running" no longer is connected to the state of the task and only shows
if we entered the body of the task or not. It has now been renamed to
"Task: In body".
The new state "Task: In body" represents that the task body has begun
the execution and is still in the stack, but the task may be paused. The
subsystem is not changed by the VTp (pause) or VTr (resume) events.
Fixes: https://pm.bsc.es/gitlab/rarias/ovni/-/issues/128
Prevents enabling more channels than required until we observe an event
of that model. Ideally we should implement this logic in the probe hook
when the models can report if they are being used in the metadata.
