[tip:sched/core] sched/deadline: Fix rt runtime corruption when dl fails its global constraints

[tip-bot for Wanpeng Li <tipbot@zytor.com>]

Commit-ID:  a1963b81deec54c113e770b0020e5f1c3188a087
Gitweb:     http://git.kernel.org/tip/a1963b81deec54c113e770b0020e5f1c3188a087
Author:     Wanpeng Li <wanpeng.li@linux.intel.com>
AuthorDate: Tue, 17 Mar 2015 19:15:31 +0800
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 27 Mar 2015 09:36:15 +0100

sched/deadline: Fix rt runtime corruption when dl fails its global constraints

One version of sched_rt_global_constaints() (the !rt-cgroup one)
changes state, therefore if we fail the later sched_dl_global_constraints()
call the state is left in an inconsistent state.

Fix this by changing the order of the calls.

Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com>
[ Improved the changelog. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@arm.com>
Link: http://lkml.kernel.org/r/1426590931-4639-2-git-send-email-wanpeng.li@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/sched/core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 043e2a1..4b3b688 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7804,7 +7804,7 @@ static int sched_rt_global_constraints(void)
 }
 #endif /* CONFIG_RT_GROUP_SCHED */
 
-static int sched_dl_global_constraints(void)
+static int sched_dl_global_validate(void)
 {
 	u64 runtime = global_rt_runtime();
 	u64 period = global_rt_period();
@@ -7905,11 +7905,11 @@ int sched_rt_handler(struct ctl_table *table, int write,
 		if (ret)
 			goto undo;
 
-		ret = sched_rt_global_constraints();
+		ret = sched_dl_global_validate();
 		if (ret)
 			goto undo;
 
-		ret = sched_dl_global_constraints();
+		ret = sched_rt_global_constraints();
 		if (ret)
 			goto undo;