From 6bc2cfdf82d56863b7cf5e86e37a662b2ae5d47e Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Tue, 26 Sep 2023 14:06:28 +0800 Subject: dax, kmem: calculate abstract distance with general interface Previously, a fixed abstract distance MEMTIER_DEFAULT_DAX_ADISTANCE is used for slow memory type in kmem driver. This limits the usage of kmem driver, for example, it cannot be used for HBM (high bandwidth memory). So, we use the general abstract distance calculation mechanism in kmem drivers to get more accurate abstract distance on systems with proper support. The original MEMTIER_DEFAULT_DAX_ADISTANCE is used as fallback only. Now, multiple memory types may be managed by kmem. These memory types are put into the "kmem_memory_types" list and protected by kmem_memory_type_lock. Link: https://lkml.kernel.org/r/20230926060628.265989-5-ying.huang@intel.com Signed-off-by: "Huang, Ying" Tested-by: Bharata B Rao Reviewed-by: Dave Jiang Reviewed-by: Alistair Popple Cc: Aneesh Kumar K.V Cc: Wei Xu Cc: Dan Williams Cc: Dave Hansen Cc: Davidlohr Bueso Cc: Johannes Weiner Cc: Jonathan Cameron Cc: Michal Hocko Cc: Yang Shi Cc: Rafael J Wysocki Signed-off-by: Andrew Morton --- drivers/dax/kmem.c | 62 ++++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 49 insertions(+), 13 deletions(-) (limited to 'drivers/dax') diff --git a/drivers/dax/kmem.c b/drivers/dax/kmem.c index c57acb73e3db..369c698b7706 100644 --- a/drivers/dax/kmem.c +++ b/drivers/dax/kmem.c @@ -49,14 +49,52 @@ struct dax_kmem_data { struct resource *res[]; }; -static struct memory_dev_type *dax_slowmem_type; +static DEFINE_MUTEX(kmem_memory_type_lock); +static LIST_HEAD(kmem_memory_types); + +static struct memory_dev_type *kmem_find_alloc_memory_type(int adist) +{ + bool found = false; + struct memory_dev_type *mtype; + + mutex_lock(&kmem_memory_type_lock); + list_for_each_entry(mtype, &kmem_memory_types, list) { + if (mtype->adistance == adist) { + found = true; + break; + } + } + if (!found) { + mtype = alloc_memory_type(adist); + if (!IS_ERR(mtype)) + list_add(&mtype->list, &kmem_memory_types); + } + mutex_unlock(&kmem_memory_type_lock); + + return mtype; +} + +static void kmem_put_memory_types(void) +{ + struct memory_dev_type *mtype, *mtn; + + mutex_lock(&kmem_memory_type_lock); + list_for_each_entry_safe(mtype, mtn, &kmem_memory_types, list) { + list_del(&mtype->list); + put_memory_type(mtype); + } + mutex_unlock(&kmem_memory_type_lock); +} + static int dev_dax_kmem_probe(struct dev_dax *dev_dax) { struct device *dev = &dev_dax->dev; unsigned long total_len = 0; struct dax_kmem_data *data; + struct memory_dev_type *mtype; int i, rc, mapped = 0; int numa_node; + int adist = MEMTIER_DEFAULT_DAX_ADISTANCE; /* * Ensure good NUMA information for the persistent memory. @@ -71,6 +109,11 @@ static int dev_dax_kmem_probe(struct dev_dax *dev_dax) return -EINVAL; } + mt_calc_adistance(numa_node, &adist); + mtype = kmem_find_alloc_memory_type(adist); + if (IS_ERR(mtype)) + return PTR_ERR(mtype); + for (i = 0; i < dev_dax->nr_range; i++) { struct range range; @@ -88,7 +131,7 @@ static int dev_dax_kmem_probe(struct dev_dax *dev_dax) return -EINVAL; } - init_node_memory_type(numa_node, dax_slowmem_type); + init_node_memory_type(numa_node, mtype); rc = -ENOMEM; data = kzalloc(struct_size(data, res, dev_dax->nr_range), GFP_KERNEL); @@ -167,7 +210,7 @@ err_reg_mgid: err_res_name: kfree(data); err_dax_kmem_data: - clear_node_memory_type(numa_node, dax_slowmem_type); + clear_node_memory_type(numa_node, mtype); return rc; } @@ -219,7 +262,7 @@ static void dev_dax_kmem_remove(struct dev_dax *dev_dax) * for that. This implies this reference will be around * till next reboot. */ - clear_node_memory_type(node, dax_slowmem_type); + clear_node_memory_type(node, NULL); } } #else @@ -251,12 +294,6 @@ static int __init dax_kmem_init(void) if (!kmem_name) return -ENOMEM; - dax_slowmem_type = alloc_memory_type(MEMTIER_DEFAULT_DAX_ADISTANCE); - if (IS_ERR(dax_slowmem_type)) { - rc = PTR_ERR(dax_slowmem_type); - goto err_dax_slowmem_type; - } - rc = dax_driver_register(&device_dax_kmem_driver); if (rc) goto error_dax_driver; @@ -264,8 +301,7 @@ static int __init dax_kmem_init(void) return rc; error_dax_driver: - put_memory_type(dax_slowmem_type); -err_dax_slowmem_type: + kmem_put_memory_types(); kfree_const(kmem_name); return rc; } @@ -275,7 +311,7 @@ static void __exit dax_kmem_exit(void) dax_driver_unregister(&device_dax_kmem_driver); if (!any_hotremove_failed) kfree_const(kmem_name); - put_memory_type(dax_slowmem_type); + kmem_put_memory_types(); } MODULE_AUTHOR("Intel Corporation"); -- cgit v1.2.3-58-ga151