A NUMA aware device tree will provide a "distance-map" node to describe distance between any two nodes. This patch introduce a new helper to parse this distance map.
Signed-off-by: Wei Chen <[email protected]> --- xen/arch/arm/numa_device_tree.c | 67 +++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) diff --git a/xen/arch/arm/numa_device_tree.c b/xen/arch/arm/numa_device_tree.c index bbe081dcd1..6e0d1d3d9f 100644 --- a/xen/arch/arm/numa_device_tree.c +++ b/xen/arch/arm/numa_device_tree.c @@ -200,3 +200,70 @@ device_tree_parse_numa_memory_node(const void *fdt, int node, return 0; } + +/* Parse NUMA distance map v1 */ +int __init +device_tree_parse_numa_distance_map_v1(const void *fdt, int node) +{ + const struct fdt_property *prop; + const __be32 *matrix; + int entry_count, len, i; + + printk(XENLOG_INFO "NUMA: parsing numa-distance-map\n"); + + prop = fdt_get_property(fdt, node, "distance-matrix", &len); + if ( !prop ) + { + printk(XENLOG_WARNING + "NUMA: No distance-matrix property in distance-map\n"); + + return -EINVAL; + } + + if ( len % sizeof(uint32_t) != 0 ) + { + printk(XENLOG_WARNING + "distance-matrix in node is not a multiple of u32\n"); + return -EINVAL; + } + + entry_count = len / sizeof(uint32_t); + if ( entry_count <= 0 ) + { + printk(XENLOG_WARNING "NUMA: Invalid distance-matrix\n"); + + return -EINVAL; + } + + matrix = (const __be32 *)prop->data; + for ( i = 0; i + 2 < entry_count; i += 3 ) + { + uint32_t from, to, distance; + + from = dt_read_number(matrix, 1); + matrix++; + to = dt_read_number(matrix, 1); + matrix++; + distance = dt_read_number(matrix, 1); + matrix++; + + if ( (from == to && distance != NUMA_LOCAL_DISTANCE) || + (from != to && distance <= NUMA_LOCAL_DISTANCE) ) + { + printk(XENLOG_WARNING + "Invalid nodes' distance from node#%d to node#%d = %d\n", + from, to, distance); + return -EINVAL; + } + + printk(XENLOG_INFO "NUMA: distance from node#%d to node#%d = %d\n", + from, to, distance); + numa_set_distance(from, to, distance); + + /* Set default distance of node B->A same as A->B */ + if (to > from) + numa_set_distance(to, from, distance); + } + + return 0; +} -- 2.25.1
