sched/deadline: Fix rt runtime corruption when dl fails its global constraints
authorWanpeng Li <wanpeng.li@linux.intel.com>
Tue, 17 Mar 2015 11:15:31 +0000 (19:15 +0800)
committerIngo Molnar <mingo@kernel.org>
Fri, 27 Mar 2015 08:36:15 +0000 (09:36 +0100)
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

index 043e2a1..4b3b688 100644 (file)
@@ -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;