In arch ia64, has following definition:
extern u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES];
#define node_distance(from,to) (numa_slit[(from) * num_online_nodes() + (to)])
num_online_nodes() is a variable value, it can be changed after hot-remove/add
a node.
In my practice, I found node distance is wrong after offline
a node in IA64 platform. For example system has 4 nodes:
node distances:
node 0 1 2 3
0: 10 21 21 32
1: 21 10 32 21
2: 21 32 10 21
3: 32 21 21 10
linux-drf:/sys/devices/system/node/node0 # cat distance
10 21 21 32
linux-drf:/sys/devices/system/node/node1 # cat distance
21 10 32 21
After offline node2:
linux-drf:/sys/devices/system/node/node0 # cat distance
10 21 32
linux-drf:/sys/devices/system/node/node1 # cat distance
32 21 32 --------->expected value is: 21 10 21
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
*/
extern u8 numa_slit[MAX_NUMNODES * MAX_NUMNODES];
-#define node_distance(from,to) (numa_slit[(from) * num_online_nodes() + (to)])
+#define node_distance(from,to) (numa_slit[(from) * MAX_NUMNODES + (to)])
extern int paddr_to_nid(unsigned long paddr);