powerpc: some changes in numa_setup_cpu()

this patches changes some error handling logics in numa_setup_cpu(),
when cpu node is not found, so:

if the cpu is possible, but not present, -1 is kept in numa_cpu_lookup_table,
so later, if the cpu is added, we could set correct numa information for it.

if the cpu is present, then we set the first online node to
numa_cpu_lookup_table instead of 0 ( in case 0 might not be an online node? )

Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Acked-by: Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 8 insertions, 6 deletions

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 3a9061e9f5dd..ec32d463cad9 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -538,7 +538,7 @@ static int of_drconf_to_nid_single(struct of_drconf_cell *drmem,
  */
 static int numa_setup_cpu(unsigned long lcpu)
 {
-        int nid;
+        int nid = -1;
         struct device_node *cpu;
 
         /*
@@ -555,19 +555,21 @@ static int numa_setup_cpu(unsigned long lcpu)
 
         if (!cpu) {
                 WARN_ON(1);
-                nid = 0;
-                goto out;
+                if (cpu_present(lcpu))
+                        goto out_present;
+                else
+                        goto out;
         }
 
         nid = of_node_to_nid_single(cpu);
 
+out_present:
         if (nid < 0 || !node_online(nid))
                 nid = first_online_node;
-out:
-        map_cpu_to_node(lcpu, nid);
 
+        map_cpu_to_node(lcpu, nid);
         of_node_put(cpu);
-
+out:
         return nid;
 }