3.5.7.6 -stable review patch. If anyone has any objections, please let me know.
------------------ From: Shawn Bohrer <sboh...@rgmadvisors.com> commit aa7f67304d1a03180f463258aa6f15a8b434e77d upstream. When the system has multiple domains do_sched_rt_period_timer() can run on any CPU and may iterate over all rt_rq in cpu_online_mask. This means when balance_runtime() is run for a given rt_rq that rt_rq may be in a different rd than the current processor. Thus if we use smp_processor_id() to get rd in do_balance_runtime() we may borrow runtime from a rt_rq that is not part of our rd. This changes do_balance_runtime to get the rd from the passed in rt_rq ensuring that we borrow runtime only from the correct rd for the given rt_rq. This fixes a BUG at kernel/sched/rt.c:687! in __disable_runtime when we try reclaim runtime lent to other rt_rq but runtime has been lent to a rt_rq in another rd. Signed-off-by: Shawn Bohrer <sboh...@rgmadvisors.com> Acked-by: Steven Rostedt <rost...@goodmis.org> Acked-by: Mike Galbraith <bitbuc...@online.de> Cc: pet...@infradead.org Link: http://lkml.kernel.org/r/1358186131-29494-1-git-send-email-sboh...@rgmadvisors.com Signed-off-by: Ingo Molnar <mi...@kernel.org> Signed-off-by: Herton Ronaldo Krzesinski <herton.krzesin...@canonical.com> --- kernel/sched/rt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 573e1ca..2a05e56 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -566,7 +566,7 @@ static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq) static int do_balance_runtime(struct rt_rq *rt_rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); - struct root_domain *rd = cpu_rq(smp_processor_id())->rd; + struct root_domain *rd = rq_of_rt_rq(rt_rq)->rd; int i, weight, more = 0; u64 rt_period; -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
