Commit ce11fae8 authored Mar 09, 2018 by Boqun Feng Committed by Paul E. McKenney Jun 26, 2018

rcu: Use the proper lockdep annotation in dump_blkd_tasks()



Sparse reported this:

| kernel/rcu/tree_plugin.h:814:9: warning: incorrect type in argument 1 (different modifiers)
| kernel/rcu/tree_plugin.h:814:9:    expected struct lockdep_map const *lock
| kernel/rcu/tree_plugin.h:814:9:    got struct lockdep_map [noderef] *<noident>

This is caused by using vanilla lockdep annotations on rcu_node::lock,
and that requires accessing ->lock of rcu_node directly. However we need
to keep rcu_node::lock __private to avoid breaking its extra ordering
guarantee. And we have a dedicated lockdep annotation for
rcu_node::lock, so use it.

Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

parent 4bc8d555

kernel/rcu/tree_plugin.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -855,7 +855,7 @@ static void dump_blkd_tasks(struct rcu_node *rnp, int ncheck)
		int i;
		struct list_head *lhp;

		lockdep_assert_held(&rnp->lock);
		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");
		i = 0;

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