Messages in this thread | | | Date | Tue, 15 Dec 2009 16:59:59 -0800 | From | Josh Triplett <> | Subject | Re: [PATCH RFC tip/core/rcu 15/18] rcu: give different levels of the rcu_node hierarchy distinct lockdep names |
| |
On Tue, Dec 15, 2009 at 03:02:38PM -0800, Paul E. McKenney wrote: > From: Paul E. McKenney <paulmck@linux.vnet.ibm.com> > > Proposed for 2.6.34, not for inclusion. > > Previously, each level of the rcu_node hierarchy had the same rather > unimaginative name: "&rcu_node_class[i]". This makes lockdep diagnostics > involving these lockdep classes less helpful than would be nice. This > patch fixes this by giving each level of the rcu_node hierarchy a distinct > name: "rcu_node_level_0", "rcu_node_level_1", and so on. > > Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> > --- > kernel/rcutree.c | 9 ++++++++- > 1 files changed, 8 insertions(+), 1 deletions(-) > > diff --git a/kernel/rcutree.c b/kernel/rcutree.c > index 0a4c328..a6e45f6 100644 > --- a/kernel/rcutree.c > +++ b/kernel/rcutree.c > @@ -1811,11 +1811,17 @@ static void __init rcu_init_levelspread(struct rcu_state *rsp) > */ > static void __init rcu_init_one(struct rcu_state *rsp) > { > + static char *buf[] = { "rcu_node_level_0", > + "rcu_node_level_1", > + "rcu_node_level_2", > + "rcu_node_level_3" }; /* Match MAX_RCU_LVLS */ > int cpustride = 1; > int i; > int j; > struct rcu_node *rnp; > > + WARN_ON_ONCE(MAX_RCU_LVLS > 4); /* Fix buf[] initialization! */ > +
BUILD_BUG_ON seems better. For that matter, please consider moving these near the rest of the level-specific defines, making them const, and ideally not emitting the strings for levels you don't have.
- Josh Triplett
| |