Commit c8c03ad9 authored May 24, 2022 by Paul E. McKenney

rcu-tasks: Flag offline CPUs in RCU Tasks Trace stall warnings

This commit tags offline CPUs with "(offline)" in RCU Tasks Trace CPU
stall warnings.  This is a debugging aid.

Signed-off-by: Paul E. McKenney <paulmck@kernel.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>

parent 9f3eb5fb

kernel/rcu/tasks.h

+2 −2

Original line number	Diff line number	Diff line
		@@ -1502,14 +1502,14 @@ static void show_stalled_task_trace(struct task_struct t, bool firstreport)
		".I"[t->trc_ipi_to_cpu >= 0],
		".i"[is_idle_tsk]);
		else
		pr_alert("P%d: %c%c%c nesting: %d%c cpu: %d\n",
		pr_alert("P%d: %c%c%c nesting: %d%c cpu: %d%s\n",
		t->pid,
		".I"[trc_rdr.ipi_to_cpu >= 0],
		".i"[is_idle_tsk],
		".N"[cpu >= 0 && tick_nohz_full_cpu(cpu)],
		trc_rdr.nesting,
		" N"[!!trc_rdr.needqs],
		cpu);
		cpu, cpu_online(cpu) ? "" : "(offline)");
		sched_show_task(t);
		}