From 64660c864f46202b932b911a69deb09805bdbaf8 Mon Sep 17 00:00:00 2001 From: Paul Turner Date: Thu, 21 Jul 2011 09:43:36 -0700 Subject: sched: Prevent interactions with throttled entities From the perspective of load-balance and shares distribution, throttled entities should be invisible. However, both of these operations work on 'active' lists and are not inherently aware of what group hierarchies may be present. In some cases this may be side-stepped (e.g. we could sideload via tg_load_down in load balance) while in others (e.g. update_shares()) it is more difficult to compute without incurring some O(n^2) costs. Instead, track hierarchicaal throttled state at time of transition. This allows us to easily identify whether an entity belongs to a throttled hierarchy and avoid incorrect interactions with it. Also, when an entity leaves a throttled hierarchy we need to advance its time averaging for shares averaging so that the elapsed throttled time is not considered as part of the cfs_rq's operation. We also use this information to prevent buddy interactions in the wakeup and yield_to() paths. Signed-off-by: Paul Turner Reviewed-by: Hidetoshi Seto Signed-off-by: Peter Zijlstra Link: http://lkml.kernel.org/r/20110721184757.777916795@google.com Signed-off-by: Ingo Molnar --- kernel/sched.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/sched.c') diff --git a/kernel/sched.c b/kernel/sched.c index 8ec1e7ac2894..5db05f6fb470 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -402,7 +402,7 @@ struct cfs_rq { u64 runtime_expires; s64 runtime_remaining; - int throttled; + int throttled, throttle_count; struct list_head throttled_list; #endif #endif -- cgit v1.2.3-59-g8ed1b