From 47199a0812535217c29933cecf468568bb37f933 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Mon, 28 May 2018 10:33:08 -0700 Subject: [PATCH] rcu: Add diagnostics for rcutorture writer stall warning This commit adds any in-the-future ->gp_seq_needed fields to the diagnostics for an rcutorture writer stall warning message. Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 7746fe1ee3fc..4915525559ac 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -606,11 +606,32 @@ EXPORT_SYMBOL_GPL(rcu_sched_force_quiescent_state); */ void show_rcu_gp_kthreads(void) { + int cpu; + struct rcu_data *rdp; + struct rcu_node *rnp; struct rcu_state *rsp; for_each_rcu_flavor(rsp) { pr_info("%s: wait state: %d ->state: %#lx\n", rsp->name, rsp->gp_state, rsp->gp_kthread->state); + rcu_for_each_node_breadth_first(rsp, rnp) { + if (ULONG_CMP_GE(rsp->gp_seq, rnp->gp_seq_needed)) + continue; + pr_info("\trcu_node %d:%d ->gp_seq %lu ->gp_seq_needed %lu\n", + rnp->grplo, rnp->grphi, rnp->gp_seq, + rnp->gp_seq_needed); + if (!rcu_is_leaf_node(rnp)) + continue; + for_each_leaf_node_possible_cpu(rnp, cpu) { + rdp = per_cpu_ptr(rsp->rda, cpu); + if (rdp->gpwrap || + ULONG_CMP_GE(rsp->gp_seq, + rdp->gp_seq_needed)) + continue; + pr_info("\tcpu %d ->gp_seq_needed %lu\n", + cpu, rdp->gp_seq_needed); + } + } /* sched_show_task(rsp->gp_kthread); */ } }