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
This commit introduces the OVNI_TRACEDIR environment variable to change
the directory where traces are generated. By default, when the envar is
not defined, the trace is still generated in the ovni directory. The
envar can take a trace directory name, a relative path to the directory,
or its absolute path. In the first case, the directory is created in the
current path $PWD.
Both libovni (rt) and ovnisync read this environment variable.
