[PATCH] x86_64 early numa init fix

The tests Alok carried out on Petr's box confirmed that cpu_to_node[BP] is
not setup early enough by numa_init_array due to the x86_64 changes in
2.6.14-rc*, and unfortunately set wrongly by the work around code in
numa_init_array().  cpu_to_node[0] gets set with 1 early and later gets set
properly to 0 during identify_cpu() when all cpus are brought up, but
confusing the numa slab in the process.

Here is a quick fix for this.  The right fix obviously is to have
cpu_to_node[bsp] setup early for numa_init_array().  The following patch
will fix the problem now, and the code can stay on even when
cpu_to_node{BP] gets fixed early correctly.

Thanks to Petr for access to his box.

Signed off by: Ravikiran Thirumalai <kiran@scalex86.org>
Signed-off-by: Alok N Kataria <alokk@calsoftinc.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/arch/x86_64/mm/numa.c b/arch/x86_64/mm/numa.c
index 68ad758..2148038 100644 (file)
--- a/arch/x86_64/mm/numa.c
+++ b/arch/x86_64/mm/numa.c
@@ -167,15 +167,14 @@ void __init numa_init_array(void)
           mapping. To avoid this fill in the mapping for all possible
           CPUs, as the number of CPUs is not known yet. 
           We round robin the existing nodes. */
-       rr = 0;
+       rr = first_node(node_online_map);
        for (i = 0; i < NR_CPUS; i++) {
                if (cpu_to_node[i] != NUMA_NO_NODE)
                        continue;
+               cpu_to_node[i] = rr;
                rr = next_node(rr, node_online_map);
                if (rr == MAX_NUMNODES)
                        rr = first_node(node_online_map);
-               cpu_to_node[i] = rr;
-               rr++; 
        }
 
 }