From cfa2b880e449bac9ff0e12e47781aff631d82b04 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Sun, 30 Jan 2011 23:56:46 -0800 Subject: [PATCH] --- yaml --- r: 234945 b: refs/heads/master c: e611eecd6f9f91d74beda8cfbb3b5e02abdeb5a1 h: refs/heads/master i: 234943: a94e19127b339afb171c033215a5c31b5ec026d0 v: v3 --- [refs] | 2 +- trunk/kernel/rcupdate.c | 5 +++++ 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/[refs] b/[refs] index 7aaaad9c1ba4..bcb70e73ee21 100644 --- a/[refs] +++ b/[refs] @@ -1,2 +1,2 @@ --- -refs/heads/master: fe8e64071a4ff5925ced4f33cb32ba090a04649c +refs/heads/master: e611eecd6f9f91d74beda8cfbb3b5e02abdeb5a1 diff --git a/trunk/kernel/rcupdate.c b/trunk/kernel/rcupdate.c index afd21d17c081..f3240e987928 100644 --- a/trunk/kernel/rcupdate.c +++ b/trunk/kernel/rcupdate.c @@ -214,6 +214,11 @@ static int rcuhead_fixup_free(void *addr, enum debug_obj_state state) * Ensure that queued callbacks are all executed. * If we detect that we are nested in a RCU read-side critical * section, we should simply fail, otherwise we would deadlock. + * Note that the machinery to reliably determine whether + * or not we are in an RCU read-side critical section + * exists only in the preemptible RCU implementations + * (TINY_PREEMPT_RCU and TREE_PREEMPT_RCU), which is why + * DEBUG_OBJECTS_RCU_HEAD is disallowed if !PREEMPT. */ if (rcu_preempt_depth() != 0 || preempt_count() != 0 || irqs_disabled()) {