cpusets, hotplug: Restructure functions that are invoked during hotplug

Separate out the cpuset related handling for CPU/Memory online/offline.
This also helps us exploit the most obvious and basic level of optimization
that any notification mechanism (CPU/Mem online/offline) has to offer us:
"We *know* why we have been invoked. So stop pretending that we are lost,
and do only the necessary amount of processing!".

And while at it, rename scan_for_empty_cpusets() to
scan_cpusets_upon_hotplug(), which is more appropriate considering how
it is restructured.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20120524141650.3692.48637.stgit@srivatsabhat.in.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 4c1d80c6b318..4b4a63d34396 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7134,7 +7134,7 @@ static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action,
 
         case CPU_ONLINE:
         case CPU_DOWN_FAILED:
-                cpuset_update_active_cpus();
+                cpuset_update_active_cpus(true);
                 break;
         default:
                 return NOTIFY_DONE;
@@ -7147,7 +7147,7 @@ static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action,
 {
         switch (action) {
         case CPU_DOWN_PREPARE:
-                cpuset_update_active_cpus();
+                cpuset_update_active_cpus(false);
                 break;
         case CPU_DOWN_PREPARE_FROZEN:
                 num_cpus_frozen++;