When ran from the sched-out path (preempt_notifier or perf_event),
p->state is irrelevant to determine preemption. You can get preempted
with !task_is_running() just fine.

The right indicator for preemption is if the task is still on the
runqueue in the sched-out path.

Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
---
 kernel/events/core.c |    7 +++----
 virt/kvm/kvm_main.c  |    2 +-
 2 files changed, 4 insertions(+), 5 deletions(-)

--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8568,13 +8568,12 @@ static void perf_event_switch(struct tas
                },
        };
 
-       if (!sched_in && task->state == TASK_RUNNING)
+       if (!sched_in && current->on_rq) {
                switch_event.event_id.header.misc |=
                                PERF_RECORD_MISC_SWITCH_OUT_PREEMPT;
+       }
 
-       perf_iterate_sb(perf_event_switch_output,
-                      &switch_event,
-                      NULL);
+       perf_iterate_sb(perf_event_switch_output, &switch_event, NULL);
 }
 
 /*
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -4869,7 +4869,7 @@ static void kvm_sched_out(struct preempt
 {
        struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
 
-       if (current->state == TASK_RUNNING) {
+       if (current->on_rq) {
                WRITE_ONCE(vcpu->preempted, true);
                WRITE_ONCE(vcpu->ready, true);
        }




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