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> > > > In this way: > > - short sleep + remaining runtime > 0 > >    - dl_defer_running stays set > >    - restart can go A->D directly > >    - no extra defer / zero-laxity penalty > > > > - stop with exhausted (or negative) runtime > >    - dl_defer_running is cleared > >    - restart must re-establish eligibility > >    - deferral / timer is armed again > >    - no stale "already running" server > > Yeah that looks like the neatest to me. > Fair tasks are a bit more penalised than now but won't be if they really sleep before consuming the runtime, which I think was the whole point of this logic. Unfortunately checking only runtime <= 0 isn't enough for the sched_ext DL server case: # Runtime of EXT task (PID 2025) is 0.000000 seconds # Runtime of RT task (PID 2026) is 4.990000 seconds # EXT task got 0.00% of total runtime not ok 2 FAIL: EXT task got less than 4.00% of runtime With the unconditional reset the EXT task gets 5% of the bandwidth. I'll add some debugging to figure out exactly what is happening. -Andrea