Re: [PATCH v2 2/2] powerpc/numa: Fill distance_lookup_table for offline nodes

[kernel test robot]

Hi Srikar,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on 031e3bd8986fffe31e1ddbf5264cccfe30c9abd7]

url:    https://github.com/0day-ci/linux/commits/Srikar-Dronamraju/Skip-numa-distance-for-offline-nodes/20210701-121809
base:   031e3bd8986fffe31e1ddbf5264cccfe30c9abd7
config: powerpc-allyesconfig (attached as .config)
compiler: powerpc64-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/715881c25ce171cc9d097d4faeb0dce60bb3e71c
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Srikar-Dronamraju/Skip-numa-distance-for-offline-nodes/20210701-121809
        git checkout 715881c25ce171cc9d097d4faeb0dce60bb3e71c
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

>> arch/powerpc/mm/numa.c:871:13: warning: no previous prototype for 'fake_update_distance_lookup_table' [-Wmissing-prototypes]
     871 | void __init fake_update_distance_lookup_table(void)
         |             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


vim +/fake_update_distance_lookup_table +871 arch/powerpc/mm/numa.c

   862	
   863	/*
   864	 * Scheduler expects unique number of node distances to be available at
   865	 * boot. It uses node distance to calculate this unique node distances. On
   866	 * POWER, node distances for offline nodes is not available. However, POWER
   867	 * already knows unique possible node distances. Fake the offline node's
   868	 * distance_lookup_table entries so that all possible node distances are
   869	 * updated.
   870	 */
 > 871	void __init fake_update_distance_lookup_table(void)
   872	{
   873		unsigned long distance_map;
   874		int i, nr_levels, nr_depth, node;
   875	
   876		if (!numa_enabled)
   877			return;
   878	
   879		if (!form1_affinity)
   880			return;
   881	
   882		/*
   883		 * distance_ref_points_depth lists the unique numa domains
   884		 * available. However it ignore LOCAL_DISTANCE. So add +1
   885		 * to get the actual number of unique distances.
   886		 */
   887		nr_depth = distance_ref_points_depth + 1;
   888	
   889		WARN_ON(nr_depth > sizeof(distance_map));
   890	
   891		bitmap_zero(&distance_map, nr_depth);
   892		bitmap_set(&distance_map, 0, 1);
   893	
   894		for_each_online_node(node) {
   895			int nd, distance = LOCAL_DISTANCE;
   896	
   897			if (node == first_online_node)
   898				continue;
   899	
   900			nd = __node_distance(node, first_online_node);
   901			for (i = 0; i < nr_depth; i++, distance *= 2) {
   902				if (distance == nd) {
   903					bitmap_set(&distance_map, i, 1);
   904					break;
   905				}
   906			}
   907			nr_levels = bitmap_weight(&distance_map, nr_depth);
   908			if (nr_levels == nr_depth)
   909				return;
   910		}
   911	
   912		for_each_node(node) {
   913			if (node_online(node))
   914				continue;
   915	
   916			i = find_first_zero_bit(&distance_map, nr_depth);
   917			if (i >= nr_depth || i == 0) {
   918				pr_warn("Levels(%d) not matching levels(%d)", nr_levels, nr_depth);
   919				return;
   920			}
   921	
   922			bitmap_set(&distance_map, i, 1);
   923			while (i--)
   924				distance_lookup_table[node][i] = node;
   925	
   926			nr_levels = bitmap_weight(&distance_map, nr_depth);
   927			if (nr_levels == nr_depth)
   928				return;
   929		}
   930	}
   931	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx

Attachment: .config.gz
Description: application/gzip