diff options
| -rw-r--r-- | include/linux/numa.h | 7 | ||||
| -rw-r--r-- | mm/mempolicy.c | 31 |
2 files changed, 38 insertions, 0 deletions
diff --git a/include/linux/numa.h b/include/linux/numa.h index 31d8bf8a951a..e6baaf6051bc 100644 --- a/include/linux/numa.h +++ b/include/linux/numa.h @@ -31,6 +31,8 @@ void __init alloc_offline_node_data(int nid); /* Generic implementation available */ int numa_nearest_node(int node, unsigned int state); +int nearest_node_nodemask(int node, nodemask_t *mask); + #ifndef memory_add_physaddr_to_nid int memory_add_physaddr_to_nid(u64 start); #endif @@ -47,6 +49,11 @@ static inline int numa_nearest_node(int node, unsigned int state) return NUMA_NO_NODE; } +static inline int nearest_node_nodemask(int node, nodemask_t *mask) +{ + return NUMA_NO_NODE; +} + static inline int memory_add_physaddr_to_nid(u64 start) { return 0; diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 162407fbf2bc..488cad280efb 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -196,6 +196,37 @@ int numa_nearest_node(int node, unsigned int state) } EXPORT_SYMBOL_GPL(numa_nearest_node); +/** + * nearest_node_nodemask - Find the node in @mask at the nearest distance + * from @node. + * + * @node: a valid node ID to start the search from. + * @mask: a pointer to a nodemask representing the allowed nodes. + * + * This function iterates over all nodes in @mask and calculates the + * distance from the starting @node, then it returns the node ID that is + * the closest to @node, or MAX_NUMNODES if no node is found. + * + * Note that @node must be a valid node ID usable with node_distance(), + * providing an invalid node ID (e.g., NUMA_NO_NODE) may result in crashes + * or unexpected behavior. + */ +int nearest_node_nodemask(int node, nodemask_t *mask) +{ + int dist, n, min_dist = INT_MAX, min_node = MAX_NUMNODES; + + for_each_node_mask(n, *mask) { + dist = node_distance(node, n); + if (dist < min_dist) { + min_dist = dist; + min_node = n; + } + } + + return min_node; +} +EXPORT_SYMBOL_GPL(nearest_node_nodemask); + struct mempolicy *get_task_policy(struct task_struct *p) { struct mempolicy *pol = p->mempolicy; |