mm: hugetlb: simplify per-node sysfs creation and removal

Patch series "simplify handling of per-node sysfs creation and removal",
v4.


This patch (of 2):

The following commit offload per-node sysfs creation and removal to a
kworker and did not say why it is needed.  And it also said "I don't know
that this is absolutely required".  It seems like the author was not sure
as well.  Since it only complicates the code, this patch will revert the
changes to simplify the code.

  39da08cb074c ("hugetlb: offload per node attribute registrations")

We could use memory hotplug notifier to do per-node sysfs creation and
removal instead of inserting those operations to node registration and
unregistration.  Then, it can reduce the code coupling between node.c and
hugetlb.c.  Also, it can simplify the code.

Link: https://lkml.kernel.org/r/20220914072603.60293-1-songmuchun@bytedance.com
Link: https://lkml.kernel.org/r/20220914072603.60293-2-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Mike Kravetz <mike.kravetz@oracle.com>
Acked-by: David Hildenbrand <david@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 4 insertions, 20 deletions

diff --git a/include/linux/node.h b/include/linux/node.h
index 9ec680dd607f..427a5975cf40 100644
--- a/include/linux/node.h
+++ b/include/linux/node.h
@@ -2,15 +2,15 @@
 /*
  * include/linux/node.h - generic node definition
  *
- * This is mainly for topological representation. We define the 
- * basic 'struct node' here, which can be embedded in per-arch 
+ * This is mainly for topological representation. We define the
+ * basic 'struct node' here, which can be embedded in per-arch
  * definitions of processors.
  *
  * Basic handling of the devices is done in drivers/base/node.c
- * and system devices are handled in drivers/base/sys.c. 
+ * and system devices are handled in drivers/base/sys.c.
  *
  * Nodes are exported via driverfs in the class/node/devices/
- * directory. 
+ * directory.
  */
 #ifndef _LINUX_NODE_H_
 #define _LINUX_NODE_H_
@@ -18,7 +18,6 @@
 #include <linux/device.h>
 #include <linux/cpumask.h>
 #include <linux/list.h>
-#include <linux/workqueue.h>
 
 /**
  * struct node_hmem_attrs - heterogeneous memory performance attributes
@@ -84,10 +83,6 @@ static inline void node_set_perf_attrs(unsigned int nid,
 struct node {
 	struct device	dev;
 	struct list_head access_list;
-
-#if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_HUGETLBFS)
-	struct work_struct	node_work;
-#endif
 #ifdef CONFIG_HMEM_REPORTING
 	struct list_head cache_attrs;
 	struct device *cache_dev;
@@ -96,7 +91,6 @@ struct node {
 
 struct memory_block;
 extern struct node *node_devices[];
-typedef  void (*node_registration_func_t)(struct node *);
 
 #if defined(CONFIG_MEMORY_HOTPLUG) && defined(CONFIG_NUMA)
 void register_memory_blocks_under_node(int nid, unsigned long start_pfn,
@@ -144,11 +138,6 @@ extern void unregister_memory_block_under_nodes(struct memory_block *mem_blk);
 extern int register_memory_node_under_compute_node(unsigned int mem_nid,
 						   unsigned int cpu_nid,
 						   unsigned access);
-
-#ifdef CONFIG_HUGETLBFS
-extern void register_hugetlbfs_with_node(node_registration_func_t doregister,
-					 node_registration_func_t unregister);
-#endif
 #else
 static inline void node_dev_init(void)
 {
@@ -176,11 +165,6 @@ static inline int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
 static inline void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
 {
 }
-
-static inline void register_hugetlbfs_with_node(node_registration_func_t reg,
-						node_registration_func_t unreg)
-{
-}
 #endif
 
 #define to_node(device) container_of(device, struct node, dev)