Peter Zijlstra cd9626e9eb sched/fair: Fix external p->on_rq users ...

Sean noted that ever since commit 152e11f6df ("sched/fair: Implement
delayed dequeue") KVM's preemption notifiers have started
mis-classifying preemption vs blocking.

Notably p->on_rq is no longer sufficient to determine if a task is
runnable or blocked -- the aforementioned commit introduces tasks that
remain on the runqueue even through they will not run again, and
should be considered blocked for many cases.

Add the task_is_runnable() helper to classify things and audit all
external users of the p->on_rq state. Also add a few comments.

Fixes: 152e11f6df ("sched/fair: Implement delayed dequeue")
Reported-by: Sean Christopherson <[email protected]>
Tested-by: Sean Christopherson <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]

2024-10-14 09:14:35 +02:00

..

kvm

sched/fair: Fix external p->on_rq users

2024-10-14 09:14:35 +02:00

lib

Revert "irqbypass: do not start cons/prod when failed connect"

2021-05-15 10:26:55 +01:00

Makefile

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