Re: sched_domains + NUMA issue

[William Lee Irwin III <wli@holomorphy.com>]

On Sun, Aug 29, 2004 at 09:18:55PM +1000, Anton Blanchard wrote:
> We are seeing errors in the sched domains debug code when SMT + NUMA is
> enabled. Nathan pointed out that the recent change to limit the number
> of nodes in a scheduling group may be causing this - in particular
> sched_domain_node_span.
> It looks like ia64 are the only ones implementing a reasonable
> node_distance, the others just do:
> #define node_distance(from,to) (from != to)
> On these architectures I wonder if we should disable the
> sched_domain_node_span code since we will just get a random grouping of
> cpus.

For fsck's sake... macro writers need to exercise more discipline.


Index: wait-2.6.9-rc1-mm1/include/linux/topology.h
===================================================================
--- wait-2.6.9-rc1-mm1.orig/include/linux/topology.h	2004-08-24 00:03:18.000000000 -0700
+++ wait-2.6.9-rc1-mm1/include/linux/topology.h	2004-08-29 09:44:35.932705488 -0700
@@ -55,7 +55,7 @@
 	for (node = 0; node < numnodes; node = __next_node_with_cpus(node))
 
 #ifndef node_distance
-#define node_distance(from,to)	(from != to)
+#define node_distance(from,to)	((from) != (to))
 #endif
 #ifndef PENALTY_FOR_NODE_WITH_CPUS
 #define PENALTY_FOR_NODE_WITH_CPUS	(1)
Index: wait-2.6.9-rc1-mm1/include/asm-ia64/numa.h
===================================================================
--- wait-2.6.9-rc1-mm1.orig/include/asm-ia64/numa.h	2004-08-24 00:02:26.000000000 -0700
+++ wait-2.6.9-rc1-mm1/include/asm-ia64/numa.h	2004-08-29 09:45:07.223948496 -0700
@@ -59,7 +59,7 @@
  */
 
 extern u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES];
-#define node_distance(from,to) (numa_slit[from * numnodes + to])
+#define node_distance(from,to) (numa_slit[(from) * numnodes + (to)])
 
 extern int paddr_to_nid(unsigned long paddr);
 
Index: wait-2.6.9-rc1-mm1/include/asm-i386/topology.h
===================================================================
--- wait-2.6.9-rc1-mm1.orig/include/asm-i386/topology.h	2004-08-24 00:02:20.000000000 -0700
+++ wait-2.6.9-rc1-mm1/include/asm-i386/topology.h	2004-08-29 09:45:24.973250192 -0700
@@ -67,7 +67,7 @@
 }
 
 /* Node-to-Node distance */
-#define node_distance(from, to) (from != to)
+#define node_distance(from, to) ((from) != (to))
 
 /* Cross-node load balancing interval. */
 #define NODE_BALANCE_RATE 100