From: Boqun Feng Date: Fri, 9 Mar 2018 01:32:18 +0000 (+0800) Subject: rcu: Use the proper lockdep annotation in dump_blkd_tasks() X-Git-Tag: v4.19-rc1~214^2^2~89^2~3 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=ce11fae8d43fe9a36823fbbfe7c44de775b7e346;p=linux.git 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] * 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 Signed-off-by: Paul E. McKenney --- diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index 17b67ecf7dff..e387ea712758 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -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;