Eric van Gyzen
2018-01-12 19:31:41 UTC
should_yield() compares thread::td_swvoltick to 'ticks' to determine
whether a thread is hogging and should yield. Since td_swvoltick
records 'ticks' /before/ the actual context switch, the calculation in
should_yield() includes any time that the thread was switched out. It
seems that should_yield() wants to know how long the thread has actually
been running. Therefore, td_swvoltick should record 'ticks' /after/
sched_switch() returns.
Does this make sense, or am I missing something?
If this makes sense, I would probably keep the current assignment in
mi_switch() and simply add a second assignment after the call to
sched_switch(). That way, db_show_thread will still show useful data
for sleeping threads. I would do the same for td_swinvolticks.
I'll be happy to make the change myself. I just want a sanity check
before I bother.
Thanks in advance,
Eric
whether a thread is hogging and should yield. Since td_swvoltick
records 'ticks' /before/ the actual context switch, the calculation in
should_yield() includes any time that the thread was switched out. It
seems that should_yield() wants to know how long the thread has actually
been running. Therefore, td_swvoltick should record 'ticks' /after/
sched_switch() returns.
Does this make sense, or am I missing something?
If this makes sense, I would probably keep the current assignment in
mi_switch() and simply add a second assignment after the call to
sched_switch(). That way, db_show_thread will still show useful data
for sleeping threads. I would do the same for td_swinvolticks.
I'll be happy to make the change myself. I just want a sanity check
before I bother.
Thanks in advance,
Eric