[PATCH tip/core/rcu 05/22] rcu: Fix typo and add additional debug

From: Paul E. McKenney
Date: Tue Jun 26 2018 - 13:15:36 EST


This commit fixes a typo and adds some additional debugging to the
message emitted when a task blocking the current grace period is listed
as blocking it when either that grace period ends or the next grace
period begins. This commit also reformats the console message for
readability.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx>
---
kernel/rcu/tree.c | 1 +
kernel/rcu/tree_plugin.h | 10 ++++++++--
2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 42ac3dd88fc5..d526c2125564 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -2316,6 +2316,7 @@ static void rcu_report_unblock_qs_rnp(struct rcu_state *rsp,
return; /* Still need more quiescent states! */
}

+ rnp->completedqs = rnp->gp_seq;
rnp_p = rnp->parent;
if (rnp_p == NULL) {
/*
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 3a6e04103de1..677b0c9f548d 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -856,8 +856,14 @@ static void dump_blkd_tasks(struct rcu_node *rnp, int ncheck)
struct list_head *lhp;

raw_lockdep_assert_held_rcu_node(rnp);
- pr_info("%s: grp: %d-%d level: %d ->qamask %#lx ->gp_tasks %p ->boost_tasks %p ->exp_tasks %p &->blkd_tasks: %p offset: %u\n", __func__, rnp->grplo, rnp->grphi, rnp->level, rnp->qsmask, rnp->gp_tasks, rnp->boost_tasks, rnp->exp_tasks, &rnp->blkd_tasks, (unsigned int)offsetof(typeof(*rnp), blkd_tasks));
- pr_cont("\t->blkd_tasks");
+ pr_info("%s: grp: %d-%d level: %d ->gp_seq %#lx ->completedqs %#lx\n",
+ __func__, rnp->grplo, rnp->grphi, rnp->level,
+ rnp->gp_seq, rnp->completedqs);
+ pr_info("%s: ->qsmask %#lx ->qsmaskinit %#lx ->qsmaskinitnext %#lx\n",
+ __func__, rnp->qsmask, rnp->qsmaskinit, rnp->qsmaskinitnext);
+ pr_info("%s: ->gp_tasks %p ->boost_tasks %p ->exp_tasks %p\n",
+ __func__, rnp->gp_tasks, rnp->boost_tasks, rnp->exp_tasks);
+ pr_info("%s: ->blkd_tasks", __func__);
i = 0;
list_for_each(lhp, &rnp->blkd_tasks) {
pr_cont(" %p", lhp);
--
2.17.1