diff options
| author | Shawn Bohrer <sbohrer@rgmadvisors.com> | 2013-01-14 11:55:31 -0600 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2013-02-20 03:15:20 +0000 |
| commit | 7fc80853e471b5442bd0e793f4eadf102cdd5faa (patch) | |
| tree | 2b7a65473144b37850d169def78c7c5648b09e25 /kernel | |
| parent | 54f9dc6f5128c165568d81e2ff493fe061008517 (diff) | |
sched/rt: Use root_domain of rt_rq not current processor
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 <sbohrer@rgmadvisors.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Acked-by: Mike Galbraith <bitbucket@online.de>
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/1358186131-29494-1-git-send-email-sbohrer@rgmadvisors.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched_rt.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 78fcacf8715e..6ad4fb394b08 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -384,7 +384,7 @@ 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; |