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The same workload when > > converted to EXT can get zero runtime if RT is 100% running, causing EXT > > processes to stall. Fix it by adding a DL server for EXT. > > > > A kselftest is also provided later to verify: > > > > ./runner -t rt_stall > > ===== START ===== > > TEST: rt_stall > > DESCRIPTION: Verify that RT tasks cannot stall SCHED_EXT tasks > > OUTPUT: > > TAP version 13 > > 1..1 > > ok 1 PASS: CFS task got more than 4.00% of runtime > > > > [ arighi: drop ->balance() now that pick_task() has an rf argument ] > > > > Cc: Luigi De Matteis > > Co-developed-by: Andrea Righi > > Signed-off-by: Andrea Righi > > Signed-off-by: Joel Fernandes > > I don't see anything preventing this to come after patch 11 so that all > sched_ext changes are at the end. Am I correct? That'd make applying the > patches easier. All the debug and deadline changes can be applied to > sched/core and I can pull that and apply sched_ext changes on top. Oh yes, we can definitely move this one. I'll reorder the patches. Thanks, -Andrea