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| author | Paul E. McKenney <paulmck@kernel.org> | 2022-05-25 18:49:26 +0200 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2022-06-20 18:22:28 +0200 |
| commit | f90f19da88bfe32dd1fdfd104de4c0526a3be701 (patch) | |
| tree | 6c57295b118e5be4fcceb97ff4eaa2bd755d90da | |
| parent | rcu-tasks: Make RCU Tasks Trace stall warnings print full .b.need_qs field (diff) | |
| download | linux-f90f19da88bfe32dd1fdfd104de4c0526a3be701.tar.xz linux-f90f19da88bfe32dd1fdfd104de4c0526a3be701.zip | |
rcu-tasks: Make RCU Tasks Trace stall warning handle idle offline tasks
When a CPU is offline, its idle task can appear to be running, but it
cannot be doing anything while CPU-hotplug operations are excluded.
This commit takes advantage of that fact by making trc_check_slow_task()
check for task_curr(t) && cpu_online(task_cpu(t)), and recording
full information in that case.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Neeraj Upadhyay <quic_neeraju@quicinc.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: KP Singh <kpsingh@kernel.org>
| -rw-r--r-- | kernel/rcu/tasks.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index 5eefbab7f2ed..64eb4d7b142e 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -1476,7 +1476,7 @@ static int trc_check_slow_task(struct task_struct *t, void *arg) { struct trc_stall_chk_rdr *trc_rdrp = arg; - if (task_curr(t)) + if (task_curr(t) && cpu_online(task_cpu(t))) return false; // It is running, so decline to inspect it. trc_rdrp->nesting = READ_ONCE(t->trc_reader_nesting); trc_rdrp->ipi_to_cpu = READ_ONCE(t->trc_ipi_to_cpu); |