x86-64, NUMA: Seperate out numa_alloc_distance() from numa_set_distance()

Alloc code is much bigger the distance setting.  Separate it out into
numa_alloc_distance() for readability.

-v2: Let alloc_numa_distance to return -ENOMEM on failing path,
     requested by tj.

-tj: Description update.  Minor tweaks including function name,
     location and return value check.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c
index 848381b..cccc01d 100644 (file)
--- a/arch/x86/mm/numa_64.c
+++ b/arch/x86/mm/numa_64.c
@@ -401,6 +401,44 @@ void __init numa_reset_distance(void)
        numa_distance = NULL;
 }
 
+static int __init numa_alloc_distance(void)
+{
+       nodemask_t nodes_parsed;
+       size_t size;
+       int i, j, cnt = 0;
+       u64 phys;
+
+       /* size the new table and allocate it */
+       nodes_parsed = numa_nodes_parsed;
+       numa_nodemask_from_meminfo(&nodes_parsed, &numa_meminfo);
+
+       for_each_node_mask(i, nodes_parsed)
+               cnt = i;
+       size = ++cnt * sizeof(numa_distance[0]);
+
+       phys = memblock_find_in_range(0, (u64)max_pfn_mapped << PAGE_SHIFT,
+                                     size, PAGE_SIZE);
+       if (phys == MEMBLOCK_ERROR) {
+               pr_warning("NUMA: Warning: can't allocate distance table!\n");
+               /* don't retry until explicitly reset */
+               numa_distance = (void *)1LU;
+               return -ENOMEM;
+       }
+       memblock_x86_reserve_range(phys, phys + size, "NUMA DIST");
+
+       numa_distance = __va(phys);
+       numa_distance_cnt = cnt;
+
+       /* fill with the default distances */
+       for (i = 0; i < cnt; i++)
+               for (j = 0; j < cnt; j++)
+                       numa_distance[i * cnt + j] = i == j ?
+                               LOCAL_DISTANCE : REMOTE_DISTANCE;
+       printk(KERN_DEBUG "NUMA: Initialized distance table, cnt=%d\n", cnt);
+
+       return 0;
+}
+
 /**
  * numa_set_distance - Set NUMA distance from one NUMA to another
  * @from: the 'from' node to set distance
@@ -413,41 +451,8 @@ void __init numa_reset_distance(void)
  */
 void __init numa_set_distance(int from, int to, int distance)
 {
-       if (!numa_distance) {
-               nodemask_t nodes_parsed;
-               size_t size;
-               int i, j, cnt = 0;
-               u64 phys;
-
-               /* size the new table and allocate it */
-               nodes_parsed = numa_nodes_parsed;
-               numa_nodemask_from_meminfo(&nodes_parsed, &numa_meminfo);
-
-               for_each_node_mask(i, nodes_parsed)
-                       cnt = i;
-               size = ++cnt * sizeof(numa_distance[0]);
-
-               phys = memblock_find_in_range(0,
-                                             (u64)max_pfn_mapped << PAGE_SHIFT,
-                                             size, PAGE_SIZE);
-               if (phys == MEMBLOCK_ERROR) {
-                       pr_warning("NUMA: Warning: can't allocate distance table!\n");
-                       /* don't retry until explicitly reset */
-                       numa_distance = (void *)1LU;
-                       return;
-               }
-               memblock_x86_reserve_range(phys, phys + size, "NUMA DIST");
-
-               numa_distance = __va(phys);
-               numa_distance_cnt = cnt;
-
-               /* fill with the default distances */
-               for (i = 0; i < cnt; i++)
-                       for (j = 0; j < cnt; j++)
-                               numa_distance[i * cnt + j] = i == j ?
-                                       LOCAL_DISTANCE : REMOTE_DISTANCE;
-               printk(KERN_DEBUG "NUMA: Initialized distance table, cnt=%d\n", cnt);
-       }
+       if (!numa_distance && numa_alloc_distance() < 0)
+               return;
 
        if (from >= numa_distance_cnt || to >= numa_distance_cnt) {
                printk_once(KERN_DEBUG "NUMA: Debug: distance out of bound, from=%d to=%d distance=%d\n",