[PATCH] sched: add option to serialize load balancing

Large sched domains can be very expensive to scan.  Add an option SD_SERIALIZE
to the sched domain flags.  If that flag is set then we make sure that no
other such domain is being balanced.

[akpm@osdl.org: build fix]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Peter Williams <pwil3058@bigpond.net.au>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Cc: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/asm-i386/topology.h b/include/asm-i386/topology.h
index 978d09596130..ac58580ad664 100644
--- a/include/asm-i386/topology.h
+++ b/include/asm-i386/topology.h
@@ -89,6 +89,7 @@ static inline int node_to_first_cpu(int node)
         .flags                  = SD_LOAD_BALANCE       \
                                 | SD_BALANCE_EXEC       \
                                 | SD_BALANCE_FORK       \
+                                | SD_SERIALIZE          \
                                 | SD_WAKE_BALANCE,      \
         .last_balance           = jiffies,              \
         .balance_interval       = 1,                    \