This patch modifies the dlock-list to use the per-subnode APIs to
manage the distributed lists. As a result, the number of lists that
need to be iterated in dlock_list_iterate() will be reduced at least
by half making the iteration a bit faster.

Signed-off-by: Waiman Long <waiman.l...@hpe.com>
---
 include/linux/dlock-list.h |   81 +++++++++++++++++++++----------------------
 lib/dlock-list.c           |   19 +++++-----
 2 files changed, 50 insertions(+), 50 deletions(-)

diff --git a/include/linux/dlock-list.h b/include/linux/dlock-list.h
index a8e1fd2..01667fc 100644
--- a/include/linux/dlock-list.h
+++ b/include/linux/dlock-list.h
@@ -20,12 +20,12 @@
 
 #include <linux/spinlock.h>
 #include <linux/list.h>
-#include <linux/percpu.h>
+#include <linux/persubnode.h>
 
 /*
  * include/linux/dlock-list.h
  *
- * A distributed (per-cpu) set of lists each of which is protected by its
+ * A distributed (per-subnode) set of lists each of which is protected by its
  * own spinlock, but acts like a single consolidated list to the callers.
  *
  * The dlock_list_head structure contains the spinlock, the other
@@ -45,19 +45,19 @@ struct dlock_list_head {
        }
 
 /*
- * Per-cpu list iteration state
+ * Per-subnode list iteration state
  */
 struct dlock_list_state {
-       int                      cpu;
+       int                      snid;  /* Subnode ID */
        spinlock_t              *lock;
-       struct list_head        *head;  /* List head of current per-cpu list */
+       struct list_head        *head;  /* List head of current per-subnode 
list */
        struct dlock_list_node  *curr;
        struct dlock_list_node  *next;
 };
 
 #define DLOCK_LIST_STATE_INIT()                        \
        {                                       \
-               .cpu  = -1,                     \
+               .snid  = -1,                    \
                .lock = NULL,                   \
                .head = NULL,                   \
                .curr = NULL,                   \
@@ -69,7 +69,7 @@ struct dlock_list_state {
 
 static inline void init_dlock_list_state(struct dlock_list_state *state)
 {
-       state->cpu  = -1;
+       state->snid  = -1;
        state->lock = NULL;
        state->head = NULL;
        state->curr = NULL;
@@ -83,12 +83,12 @@ static inline void init_dlock_list_state(struct 
dlock_list_state *state)
 #endif
 
 /*
- * Next per-cpu list entry
+ * Next per-subnode list entry
  */
 #define dlock_list_next_entry(pos, member) list_next_entry(pos, member.list)
 
 /*
- * Per-cpu node data structure
+ * Per-subnode node data structure
  */
 struct dlock_list_node {
        struct list_head list;
@@ -109,50 +109,50 @@ static inline void init_dlock_list_node(struct 
dlock_list_node *node)
 }
 
 static inline void
-free_dlock_list_head(struct dlock_list_head __percpu **pdlock_head)
+free_dlock_list_head(struct dlock_list_head __persubnode **pdlock_head)
 {
-       free_percpu(*pdlock_head);
+       free_persubnode(*pdlock_head);
        *pdlock_head = NULL;
 }
 
 /*
- * Check if all the per-cpu lists are empty
+ * Check if all the per-subnode lists are empty
  */
-static inline bool dlock_list_empty(struct dlock_list_head __percpu 
*dlock_head)
+static inline bool dlock_list_empty(struct dlock_list_head __persubnode 
*dlock_head)
 {
-       int cpu;
+       int snid;
 
-       for_each_possible_cpu(cpu)
-               if (!list_empty(&per_cpu_ptr(dlock_head, cpu)->list))
+       for_each_subnode(snid)
+               if (!list_empty(&per_subnode_ptr(dlock_head, snid)->list))
                        return false;
        return true;
 }
 
 /*
- * Helper function to find the first entry of the next per-cpu list
- * It works somewhat like for_each_possible_cpu(cpu).
+ * Helper function to find the first entry of the next per-subnode list
+ * It works somewhat like for_each_subnode(snid).
  *
  * Return: true if the entry is found, false if all the lists exhausted
  */
 static __always_inline bool
-__dlock_list_next_cpu(struct dlock_list_head __percpu *head,
+__dlock_list_next_subnode(struct dlock_list_head __persubnode *head,
                      struct dlock_list_state *state)
 {
        if (state->lock)
                spin_unlock(state->lock);
-next_cpu:
+next_subnode:
        /*
-        * for_each_possible_cpu(cpu)
+        * for_each_subnode(snid)
         */
-       state->cpu = cpumask_next(state->cpu, cpu_possible_mask);
-       if (state->cpu >= nr_cpu_ids)
-               return false;   /* All the per-cpu lists iterated */
+       state->snid = cpumask_next(state->snid, subnode_mask);
+       if (state->snid >= nr_subnode_ids)
+               return false;   /* All the per-subnode lists iterated */
 
-       state->head = &per_cpu_ptr(head, state->cpu)->list;
+       state->head = &per_subnode_ptr(head, state->snid)->list;
        if (list_empty(state->head))
-               goto next_cpu;
+               goto next_subnode;
 
-       state->lock = &per_cpu_ptr(head, state->cpu)->lock;
+       state->lock = &per_subnode_ptr(head, state->snid)->lock;
        spin_lock(state->lock);
        /*
         * There is a slight chance that the list may become empty just
@@ -161,7 +161,7 @@ next_cpu:
         */
        if (list_empty(state->head)) {
                spin_unlock(state->lock);
-               goto next_cpu;
+               goto next_subnode;
        }
        state->curr = list_entry(state->head->next,
                                 struct dlock_list_node, list);
@@ -169,11 +169,11 @@ next_cpu:
 }
 
 /*
- * Iterate to the next entry of the group of per-cpu lists
+ * Iterate to the next entry of the group of per-subnode lists
  *
  * Return: true if the next entry is found, false if all the entries iterated
  */
-static inline bool dlock_list_iterate(struct dlock_list_head __percpu *head,
+static inline bool dlock_list_iterate(struct dlock_list_head __persubnode 
*head,
                                      struct dlock_list_state *state)
 {
        /*
@@ -184,10 +184,10 @@ static inline bool dlock_list_iterate(struct 
dlock_list_head __percpu *head,
 
        if (!state->curr || (&state->curr->list == state->head)) {
                /*
-                * The current per-cpu list has been exhausted, try the next
-                * per-cpu list.
+                * The current per-subnode list has been exhausted, try the next
+                * per-subnode list.
                 */
-               if (!__dlock_list_next_cpu(head, state))
+               if (!__dlock_list_next_subnode(head, state))
                        return false;
        }
 
@@ -196,13 +196,13 @@ static inline bool dlock_list_iterate(struct 
dlock_list_head __percpu *head,
 }
 
 /*
- * Iterate to the next entry of the group of per-cpu lists and safe
+ * Iterate to the next entry of the group of per-subnode lists and safe
  * against removal of list_entry
  *
  * Return: true if the next entry is found, false if all the entries iterated
  */
 static inline bool
-dlock_list_iterate_safe(struct dlock_list_head __percpu *head,
+dlock_list_iterate_safe(struct dlock_list_head __persubnode *head,
                        struct dlock_list_state *state)
 {
        /*
@@ -215,10 +215,10 @@ dlock_list_iterate_safe(struct dlock_list_head __percpu 
*head,
 
        if (!state->curr || (&state->curr->list == state->head)) {
                /*
-                * The current per-cpu list has been exhausted, try the next
-                * per-cpu list.
+                * The current per-subnode list has been exhausted, try the next
+                * per-subnode list.
                 */
-               if (!__dlock_list_next_cpu(head, state))
+               if (!__dlock_list_next_subnode(head, state))
                        return false;
                state->next = list_next_entry(state->curr, list);
        }
@@ -228,8 +228,7 @@ dlock_list_iterate_safe(struct dlock_list_head __percpu 
*head,
 }
 
 extern void dlock_list_add(struct dlock_list_node *node,
-                          struct dlock_list_head __percpu *head);
+                          struct dlock_list_head __persubnode *head);
 extern void dlock_list_del(struct dlock_list_node *node);
-extern int  init_dlock_list_head(struct dlock_list_head __percpu 
**pdlock_head);
-
+extern int  init_dlock_list_head(struct dlock_list_head __persubnode 
**pdlock_head);
 #endif /* __LINUX_DLOCK_LIST_H */
diff --git a/lib/dlock-list.c b/lib/dlock-list.c
index e1a1930..05bbf45 100644
--- a/lib/dlock-list.c
+++ b/lib/dlock-list.c
@@ -25,20 +25,21 @@
 static struct lock_class_key dlock_list_key;
 
 /*
- * Initialize the per-cpu list head
+ * Initialize the per-subnode list head
  */
-int init_dlock_list_head(struct dlock_list_head __percpu **pdlock_head)
+int init_dlock_list_head(struct dlock_list_head __persubnode **pdlock_head)
 {
        struct dlock_list_head *dlock_head;
-       int cpu;
+       int snid;
 
-       dlock_head = alloc_percpu(struct dlock_list_head);
+       dlock_head = alloc_persubnode(struct dlock_list_head);
        if (!dlock_head)
                return -ENOMEM;
 
-       for_each_possible_cpu(cpu) {
-               struct dlock_list_head *head = per_cpu_ptr(dlock_head, cpu);
+       for_each_subnode(snid) {
+               struct dlock_list_head *head;
 
+               head = per_subnode_ptr(dlock_head, snid);
                INIT_LIST_HEAD(&head->list);
                head->lock = __SPIN_LOCK_UNLOCKED(&head->lock);
                lockdep_set_class(&head->lock, &dlock_list_key);
@@ -54,19 +55,19 @@ int init_dlock_list_head(struct dlock_list_head __percpu 
**pdlock_head)
  * So we still need to use a lock to protect the content of the list.
  */
 void dlock_list_add(struct dlock_list_node *node,
-                   struct dlock_list_head __percpu *head)
+                   struct dlock_list_head __persubnode *head)
 {
        struct dlock_list_head *myhead;
 
        /*
         * Disable preemption to make sure that CPU won't gets changed.
         */
-       myhead = get_cpu_ptr(head);
+       myhead = get_subnode_ptr(head);
        spin_lock(&myhead->lock);
        node->lockptr = &myhead->lock;
        list_add(&node->list, &myhead->list);
        spin_unlock(&myhead->lock);
-       put_cpu_ptr(head);
+       put_subnode_ptr(head);
 }
 
 /*
-- 
1.7.1

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