[SPARC64]: Make cpu_present_map available earlier.

The change to kernel/sched.c's init code to use for_each_cpu()
requires that the cpu_possible_map be setup much earlier.

Set it up via setup_arch(), constrained to NR_CPUS, and later
constrain it to max_cpus in smp_prepare_cpus().

This fixes SMP booting on sparc64.

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 21 insertions, 9 deletions

diff --git a/arch/sparc64/kernel/setup.c b/arch/sparc64/kernel/setup.c
index 054461e6946d..158bd31e15b7 100644
--- a/arch/sparc64/kernel/setup.c
+++ b/arch/sparc64/kernel/setup.c
@@ -542,6 +542,8 @@ void __init setup_arch(char **cmdline_p)
         }
 #endif
 
+        smp_setup_cpu_possible_map();
+
         paging_init();
 }
 
diff --git a/arch/sparc64/kernel/smp.c b/arch/sparc64/kernel/smp.c
index 1fb6323e65a4..1f7ad8a69052 100644
--- a/arch/sparc64/kernel/smp.c
+++ b/arch/sparc64/kernel/smp.c
@@ -1079,18 +1079,12 @@ int setup_profiling_timer(unsigned int multiplier)
         return 0;
 }
 
+/* Constrain the number of cpus to max_cpus.  */
 void __init smp_prepare_cpus(unsigned int max_cpus)
 {
-        int instance, mid;
-
-        instance = 0;
-        while (!cpu_find_by_instance(instance, NULL, &mid)) {
-                if (mid < max_cpus)
-                        cpu_set(mid, phys_cpu_present_map);
-                instance++;
-        }
-
         if (num_possible_cpus() > max_cpus) {
+                int instance, mid;
+
                 instance = 0;
                 while (!cpu_find_by_instance(instance, NULL, &mid)) {
                         if (mid != boot_cpu_id) {
@@ -1105,6 +1099,22 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
         smp_store_cpu_info(boot_cpu_id);
 }
 
+/* Set this up early so that things like the scheduler can init
+ * properly.  We use the same cpu mask for both the present and
+ * possible cpu map.
+ */
+void __init smp_setup_cpu_possible_map(void)
+{
+        int instance, mid;
+
+        instance = 0;
+        while (!cpu_find_by_instance(instance, NULL, &mid)) {
+                if (mid < NR_CPUS)
+                        cpu_set(mid, phys_cpu_present_map);
+                instance++;
+        }
+}
+
 void __devinit smp_prepare_boot_cpu(void)
 {
         if (hard_smp_processor_id() >= NR_CPUS) {