diff --git a/Documentation/ABI/stable/sysfs-devices-node b/Documentation/ABI/stable/sysfs-devices-node index 735a40a3f9b23b53e217b2c8de881239a9aa1ae1..f7ce68fbd4b9a77d2ba353becedfb025c3152d72 100644 --- a/Documentation/ABI/stable/sysfs-devices-node +++ b/Documentation/ABI/stable/sysfs-devices-node @@ -142,3 +142,37 @@ Contact: Keith Busch Description: This node's write latency in nanoseconds when access from nodes found in this class's linked initiators. + +What: /sys/devices/system/node/nodeX/memory_side_cache/indexY/ +Date: December 2018 +Contact: Keith Busch +Description: + The directory containing attributes for the memory-side cache + level 'Y'. + +What: /sys/devices/system/node/nodeX/memory_side_cache/indexY/indexing +Date: December 2018 +Contact: Keith Busch +Description: + The caches associativity indexing: 0 for direct mapped, + non-zero if indexed. + +What: /sys/devices/system/node/nodeX/memory_side_cache/indexY/line_size +Date: December 2018 +Contact: Keith Busch +Description: + The number of bytes accessed from the next cache level on a + cache miss. + +What: /sys/devices/system/node/nodeX/memory_side_cache/indexY/size +Date: December 2018 +Contact: Keith Busch +Description: + The size of this memory side cache in bytes. + +What: /sys/devices/system/node/nodeX/memory_side_cache/indexY/write_policy +Date: December 2018 +Contact: Keith Busch +Description: + The cache write policy: 0 for write-back, 1 for write-through, + other or unknown. diff --git a/drivers/base/node.c b/drivers/base/node.c index 56e62721ca43faad7cf46cd774d1dba22250b13a..af76bf54e913746d39bb248ae879f949aab3f258 100644 --- a/drivers/base/node.c +++ b/drivers/base/node.c @@ -205,6 +205,155 @@ void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs, } } } + +/** + * struct node_cache_info - Internal tracking for memory node caches + * @dev: Device represeting the cache level + * @node: List element for tracking in the node + * @cache_attrs:Attributes for this cache level + */ +struct node_cache_info { + struct device dev; + struct list_head node; + struct node_cache_attrs cache_attrs; +}; +#define to_cache_info(device) container_of(device, struct node_cache_info, dev) + +#define CACHE_ATTR(name, fmt) \ +static ssize_t name##_show(struct device *dev, \ + struct device_attribute *attr, \ + char *buf) \ +{ \ + return sprintf(buf, fmt "\n", to_cache_info(dev)->cache_attrs.name);\ +} \ +DEVICE_ATTR_RO(name); + +CACHE_ATTR(size, "%llu") +CACHE_ATTR(line_size, "%u") +CACHE_ATTR(indexing, "%u") +CACHE_ATTR(write_policy, "%u") + +static struct attribute *cache_attrs[] = { + &dev_attr_indexing.attr, + &dev_attr_size.attr, + &dev_attr_line_size.attr, + &dev_attr_write_policy.attr, + NULL, +}; +ATTRIBUTE_GROUPS(cache); + +static void node_cache_release(struct device *dev) +{ + kfree(dev); +} + +static void node_cacheinfo_release(struct device *dev) +{ + struct node_cache_info *info = to_cache_info(dev); + kfree(info); +} + +static void node_init_cache_dev(struct node *node) +{ + struct device *dev; + + dev = kzalloc(sizeof(*dev), GFP_KERNEL); + if (!dev) + return; + + dev->parent = &node->dev; + dev->release = node_cache_release; + if (dev_set_name(dev, "memory_side_cache")) + goto free_dev; + + if (device_register(dev)) + goto free_name; + + pm_runtime_no_callbacks(dev); + node->cache_dev = dev; + return; +free_name: + kfree_const(dev->kobj.name); +free_dev: + kfree(dev); +} + +/** + * node_add_cache() - add cache attribute to a memory node + * @nid: Node identifier that has new cache attributes + * @cache_attrs: Attributes for the cache being added + */ +void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs) +{ + struct node_cache_info *info; + struct device *dev; + struct node *node; + + if (!node_online(nid) || !node_devices[nid]) + return; + + node = node_devices[nid]; + list_for_each_entry(info, &node->cache_attrs, node) { + if (info->cache_attrs.level == cache_attrs->level) { + dev_warn(&node->dev, + "attempt to add duplicate cache level:%d\n", + cache_attrs->level); + return; + } + } + + if (!node->cache_dev) + node_init_cache_dev(node); + if (!node->cache_dev) + return; + + info = kzalloc(sizeof(*info), GFP_KERNEL); + if (!info) + return; + + dev = &info->dev; + dev->parent = node->cache_dev; + dev->release = node_cacheinfo_release; + dev->groups = cache_groups; + if (dev_set_name(dev, "index%d", cache_attrs->level)) + goto free_cache; + + info->cache_attrs = *cache_attrs; + if (device_register(dev)) { + dev_warn(&node->dev, "failed to add cache level:%d\n", + cache_attrs->level); + goto free_name; + } + pm_runtime_no_callbacks(dev); + list_add_tail(&info->node, &node->cache_attrs); + return; +free_name: + kfree_const(dev->kobj.name); +free_cache: + kfree(info); +} + +static void node_remove_caches(struct node *node) +{ + struct node_cache_info *info, *next; + + if (!node->cache_dev) + return; + + list_for_each_entry_safe(info, next, &node->cache_attrs, node) { + list_del(&info->node); + device_unregister(&info->dev); + } + device_unregister(node->cache_dev); +} + +static void node_init_caches(unsigned int nid) +{ + INIT_LIST_HEAD(&node_devices[nid]->cache_attrs); +} +#else +static void node_init_caches(unsigned int nid) { } +static void node_remove_caches(struct node *node) { } #endif #define K(x) ((x) << (PAGE_SHIFT - 10)) @@ -489,6 +638,7 @@ void unregister_node(struct node *node) { hugetlb_unregister_node(node); /* no-op, if memoryless node */ node_remove_accesses(node); + node_remove_caches(node); device_unregister(&node->dev); } @@ -781,6 +931,7 @@ int __register_one_node(int nid) INIT_LIST_HEAD(&node_devices[nid]->access_list); /* initialize work queue for memory hot plug */ init_node_hugetlb_work(nid); + node_init_caches(nid); return error; } diff --git a/include/linux/node.h b/include/linux/node.h index 4139d728f8b381a158b66ea57d128c0c3520c806..1a557c589ecb9772a63214e2c5e2c39f1211a95e 100644 --- a/include/linux/node.h +++ b/include/linux/node.h @@ -35,10 +35,45 @@ struct node_hmem_attrs { unsigned int write_latency; }; +enum cache_indexing { + NODE_CACHE_DIRECT_MAP, + NODE_CACHE_INDEXED, + NODE_CACHE_OTHER, +}; + +enum cache_write_policy { + NODE_CACHE_WRITE_BACK, + NODE_CACHE_WRITE_THROUGH, + NODE_CACHE_WRITE_OTHER, +}; + +/** + * struct node_cache_attrs - system memory caching attributes + * + * @indexing: The ways memory blocks may be placed in cache + * @write_policy: Write back or write through policy + * @size: Total size of cache in bytes + * @line_size: Number of bytes fetched on a cache miss + * @level: The cache hierarchy level + */ +struct node_cache_attrs { + enum cache_indexing indexing; + enum cache_write_policy write_policy; + u64 size; + u16 line_size; + u8 level; +}; + #ifdef CONFIG_HMEM_REPORTING +void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs); void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs, unsigned access); #else +static inline void node_add_cache(unsigned int nid, + struct node_cache_attrs *cache_attrs) +{ +} + static inline void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs, unsigned access) @@ -53,6 +88,10 @@ struct node { #if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS) struct work_struct node_work; #endif +#ifdef CONFIG_HMEM_REPORTING + struct list_head cache_attrs; + struct device *cache_dev; +#endif }; struct memory_block;