From 4d8776f3cc03da1bab0ffa507675ef1e184990c8 Mon Sep 17 00:00:00 2001 From: Patrick Bellasi Date: Fri, 29 Jul 2016 16:09:03 +0100 Subject: [PATCH] FIXUP: sched/tune: do initialization as a postcore_initicall SchedTune needs to walk the scheduling domains to compute the energy normalization constants used for PE space filtering. To build such constants we need the energy model data for each CPU in the system. However, by walking the SDs as a late initcall stage, the userspace has been already initialized and it could happen that some CPUs are hotplugged out. For example, this could happen if a user-space thermal manager daemon detects that CPUs are to much hot during the boot process. To avoid such a race condition we can anticipate the SchedTune initialization code to be a postcore_initicall. This allows to keep the SchedTune initialization code as simple as an initcall while still safely relaying on SDs provided data. Such calls are executed before user-space is initialized and thus, apart from the case of unlucky early-init kernel space generated hotplugs, this solution should be safe enough to get all the data we need. Signed-off-by: Patrick Bellasi [jstultz: fwdported to 4.4] Signed-off-by: John Stultz --- kernel/sched/tune.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched/tune.c b/kernel/sched/tune.c index 644f8e9ee96f..bd7f319ce53e 100644 --- a/kernel/sched/tune.c +++ b/kernel/sched/tune.c @@ -946,4 +946,4 @@ nodata: rcu_read_unlock(); return -EINVAL; } -late_initcall(schedtune_init); +postcore_initcall(schedtune_init); -- 2.34.1