powerpc: Only set numa node information for present cpus at boottime
authorLi Zhong <zhong@linux.vnet.ibm.com>
Wed, 27 Aug 2014 09:34:00 +0000 (17:34 +0800)
committerMichael Ellerman <mpe@ellerman.id.au>
Thu, 25 Sep 2014 13:14:53 +0000 (23:14 +1000)
As Nish suggested, it makes more sense to init the numa node informatiion
for present cpus at boottime, which could also avoid WARN_ON(1) in
numa_setup_cpu().

With this change, we also need to change the smp_prepare_cpus() to set up
numa information only on present cpus.

For those possible, but not present cpus, their numa information
will be set up after they are started, as the original code did before commit
2fabf084b6ad.

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>
Tested-by: Cyril Bur <cyril.bur@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
arch/powerpc/kernel/smp.c
arch/powerpc/mm/numa.c

index 4866d5dbd420e185fd395c9c01df7ac8b4bfc274..71e186d5f331a3320259e4d0ad432d29944a684e 100644 (file)
@@ -380,8 +380,11 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
                /*
                 * numa_node_id() works after this.
                 */
-               set_cpu_numa_node(cpu, numa_cpu_lookup_table[cpu]);
-               set_cpu_numa_mem(cpu, local_memory_node(numa_cpu_lookup_table[cpu]));
+               if (cpu_present(cpu)) {
+                       set_cpu_numa_node(cpu, numa_cpu_lookup_table[cpu]);
+                       set_cpu_numa_mem(cpu,
+                               local_memory_node(numa_cpu_lookup_table[cpu]));
+               }
        }
 
        cpumask_set_cpu(boot_cpuid, cpu_sibling_mask(boot_cpuid));
@@ -729,6 +732,9 @@ void start_secondary(void *unused)
        }
        traverse_core_siblings(cpu, true);
 
+       set_numa_node(numa_cpu_lookup_table[cpu]);
+       set_numa_mem(local_memory_node(numa_cpu_lookup_table[cpu]));
+
        smp_wmb();
        notify_cpu_starting(cpu);
        set_cpu_online(cpu, true);
index 9918c020085770b44c6a5275d0c9beae52ae1fb2..3a9061e9f5dd3c69d0183a2925754fdce955fee7 100644 (file)
@@ -1127,7 +1127,7 @@ void __init do_init_bootmem(void)
         * even before we online them, so that we can use cpu_to_{node,mem}
         * early in boot, cf. smp_prepare_cpus().
         */
-       for_each_possible_cpu(cpu) {
+       for_each_present_cpu(cpu) {
                numa_setup_cpu((unsigned long)cpu);
        }
 }