sched: Fully integrate cpus_active_map and root-domain code

Reflect "active" cpus in the rq->rd->online field, instead of
the online_map.

The motivation is that things that use the root-domain code
(such as cpupri) only care about cpus classified as "active"
anyway. By synchronizing the root-domain state with the active
map, we allow several optimizations.

For instance, we can remove an extra cpumask_and from the
scheduler hotpath by utilizing rq->rd->online (since it is now
a cached version of cpu_active_map & rq->rd->span).

Signed-off-by: Gregory Haskins <ghaskins@novell.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Max Krasnyansky <maxk@qualcomm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20090730145723.25226.24493.stgit@dev.haskins.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/kernel/sched.c b/kernel/sched.c
index 613fee5..475138c 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -7927,7 +7927,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
        rq->rd = rd;
 
        cpumask_set_cpu(rq->cpu, rd->span);
-       if (cpumask_test_cpu(rq->cpu, cpu_online_mask))
+       if (cpumask_test_cpu(rq->cpu, cpu_active_mask))
                set_rq_online(rq);
 
        spin_unlock_irqrestore(&rq->lock, flags);

diff --cc kernel/sched_fair.c
Simple merge

diff --cc kernel/sched_rt.c
Simple merge