Hi, I am trying to map out how a task gets scheduled according to a scheduling algorithm once a user writes rtems_task_create() and later rtems_task_start() in the source file.
On debugging with gdb, I came to realize that the rtems_task_start() function calls _Thread_Start() (cpukit/rtems/src/taskstart.c : 56) then _Thread_Start() calls _Thread_Dispatch_enable() ( cpukit/score/src/threadstart.c : 50 ) then _Thread_Dispatch_enable() calls _Thread_Do_dispatch( ) (cpukit/score/src/threaddispatch.c : 377) and _Thread_Do_dispatch calls _Thread_Get_heir_and_make_it_executing() (threaddispatch.c : 282). _Thread_Get_heir_and_make_it_executing( cpu_self ) forcefully executes the heir thread on the cpu_self. (cpukit/include/rtems/score/threadimpl.h : 1117) If I am right, this flow of code makes the thread created by rtems_task_create(..., id) execute on a CPU when rtems_task_start(..., id) is called. Shouldn't this decision of executing a thread on any CPU be in the hands of the scheduler? I'd be grateful if someone could provide their views on this. Also, what is thread_dispatch_disable_level? Please know that I skipped reading some if conditions and some code related to ISRs and other things that weren't directly related to scheduling. Thanks, Richi.
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