diff options
Diffstat (limited to 'numa.c')
| -rw-r--r-- | numa.c | 137 |
1 files changed, 135 insertions, 2 deletions
@@ -51,6 +51,7 @@ static int max_numa_nodeid; /* Highest specified NUMA node ID, plus one. * For all nodes, nodeid < max_numa_nodeid */ int nb_numa_nodes; +bool have_numa_distance; NodeInfo numa_info[MAX_NODES]; void numa_set_mem_node_id(ram_addr_t addr, uint64_t size, uint32_t node) @@ -140,7 +141,7 @@ uint32_t numa_get_node(ram_addr_t addr, Error **errp) return -1; } -static void numa_node_parse(NumaNodeOptions *node, QemuOpts *opts, Error **errp) +static void parse_numa_node(NumaNodeOptions *node, QemuOpts *opts, Error **errp) { uint16_t nodenr; uint16List *cpus = NULL; @@ -212,6 +213,43 @@ static void numa_node_parse(NumaNodeOptions *node, QemuOpts *opts, Error **errp) max_numa_nodeid = MAX(max_numa_nodeid, nodenr + 1); } +static void parse_numa_distance(NumaDistOptions *dist, Error **errp) +{ + uint16_t src = dist->src; + uint16_t dst = dist->dst; + uint8_t val = dist->val; + + if (src >= MAX_NODES || dst >= MAX_NODES) { + error_setg(errp, + "Invalid node %" PRIu16 + ", max possible could be %" PRIu16, + MAX(src, dst), MAX_NODES); + return; + } + + if (!numa_info[src].present || !numa_info[dst].present) { + error_setg(errp, "Source/Destination NUMA node is missing. " + "Please use '-numa node' option to declare it first."); + return; + } + + if (val < NUMA_DISTANCE_MIN) { + error_setg(errp, "NUMA distance (%" PRIu8 ") is invalid, " + "it shouldn't be less than %d.", + val, NUMA_DISTANCE_MIN); + return; + } + + if (src == dst && val != NUMA_DISTANCE_MIN) { + error_setg(errp, "Local distance of node %d should be %d.", + src, NUMA_DISTANCE_MIN); + return; + } + + numa_info[src].distance[dst] = val; + have_numa_distance = true; +} + static int parse_numa(void *opaque, QemuOpts *opts, Error **errp) { NumaOptions *object = NULL; @@ -229,12 +267,18 @@ static int parse_numa(void *opaque, QemuOpts *opts, Error **errp) switch (object->type) { case NUMA_OPTIONS_TYPE_NODE: - numa_node_parse(&object->u.node, opts, &err); + parse_numa_node(&object->u.node, opts, &err); if (err) { goto end; } nb_numa_nodes++; break; + case NUMA_OPTIONS_TYPE_DIST: + parse_numa_distance(&object->u.dist, &err); + if (err) { + goto end; + } + break; default: abort(); } @@ -294,6 +338,75 @@ static void validate_numa_cpus(void) g_free(seen_cpus); } +/* If all node pair distances are symmetric, then only distances + * in one direction are enough. If there is even one asymmetric + * pair, though, then all distances must be provided. The + * distance from a node to itself is always NUMA_DISTANCE_MIN, + * so providing it is never necessary. + */ +static void validate_numa_distance(void) +{ + int src, dst; + bool is_asymmetrical = false; + + for (src = 0; src < nb_numa_nodes; src++) { + for (dst = src; dst < nb_numa_nodes; dst++) { + if (numa_info[src].distance[dst] == 0 && + numa_info[dst].distance[src] == 0) { + if (src != dst) { + error_report("The distance between node %d and %d is " + "missing, at least one distance value " + "between each nodes should be provided.", + src, dst); + exit(EXIT_FAILURE); + } + } + + if (numa_info[src].distance[dst] != 0 && + numa_info[dst].distance[src] != 0 && + numa_info[src].distance[dst] != + numa_info[dst].distance[src]) { + is_asymmetrical = true; + } + } + } + + if (is_asymmetrical) { + for (src = 0; src < nb_numa_nodes; src++) { + for (dst = 0; dst < nb_numa_nodes; dst++) { + if (src != dst && numa_info[src].distance[dst] == 0) { + error_report("At least one asymmetrical pair of " + "distances is given, please provide distances " + "for both directions of all node pairs."); + exit(EXIT_FAILURE); + } + } + } + } +} + +static void complete_init_numa_distance(void) +{ + int src, dst; + + /* Fixup NUMA distance by symmetric policy because if it is an + * asymmetric distance table, it should be a complete table and + * there would not be any missing distance except local node, which + * is verified by validate_numa_distance above. + */ + for (src = 0; src < nb_numa_nodes; src++) { + for (dst = 0; dst < nb_numa_nodes; dst++) { + if (numa_info[src].distance[dst] == 0) { + if (src == dst) { + numa_info[src].distance[dst] = NUMA_DISTANCE_MIN; + } else { + numa_info[src].distance[dst] = numa_info[dst].distance[src]; + } + } + } + } +} + void parse_numa_opts(MachineClass *mc) { int i; @@ -390,6 +503,26 @@ void parse_numa_opts(MachineClass *mc) } validate_numa_cpus(); + + /* QEMU needs at least all unique node pair distances to build + * the whole NUMA distance table. QEMU treats the distance table + * as symmetric by default, i.e. distance A->B == distance B->A. + * Thus, QEMU is able to complete the distance table + * initialization even though only distance A->B is provided and + * distance B->A is not. QEMU knows the distance of a node to + * itself is always 10, so A->A distances may be omitted. When + * the distances of two nodes of a pair differ, i.e. distance + * A->B != distance B->A, then that means the distance table is + * asymmetric. In this case, the distances for both directions + * of all node pairs are required. + */ + if (have_numa_distance) { + /* Validate enough NUMA distance information was provided. */ + validate_numa_distance(); + + /* Validation succeeded, now fill in any missing distances. */ + complete_init_numa_distance(); + } } else { numa_set_mem_node_id(0, ram_size, 0); } |