Node vs Threads in scheduling

[Sebastian Huber]

On 17/08/2020 14:35, Richi Dubey wrote:

> Also, can someone please explain how the thread could in the ready 
> state while the node is in a scheduled state in this 
> <https://git.rtems.org/rtems/tree/cpukit/include/rtems/score/schedulersmpimpl.h#n1517> 
> conditional block ?

The MrsP locking protocol performs busy waiting will a thread is 
blocked. The busy waiting is carried out by idle threads.

In the referenced conditional block, the thread is ready to execute 
again and its scheduler node is scheduled. In this case, it uses an idle 
thread to perform the busy wait. So, we have to get rid of the idle 
thread and use the node for its own thread.