net, rds, Replace xlist in net/rds/xlist.h with llist
The functionality of xlist and llist is almost same. This patch
replace xlist with llist to avoid code duplication.
Known issues: don't know how to test this, need special hardware?
Signed-off-by: Huang Ying <ying.huang@intel.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Andy Grover <andy.grover@oracle.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/rds/ib_rdma.c b/net/rds/ib_rdma.c
index 819c35a..e8fdb17 100644
--- a/net/rds/ib_rdma.c
+++ b/net/rds/ib_rdma.c
@@ -33,10 +33,10 @@
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/rculist.h>
+#include <linux/llist.h>
#include "rds.h"
#include "ib.h"
-#include "xlist.h"
static DEFINE_PER_CPU(unsigned long, clean_list_grace);
#define CLEAN_LIST_BUSY_BIT 0
@@ -49,7 +49,7 @@
struct rds_ib_mr_pool *pool;
struct ib_fmr *fmr;
- struct xlist_head xlist;
+ struct llist_node llnode;
/* unmap_list is for freeing */
struct list_head unmap_list;
@@ -71,9 +71,9 @@
atomic_t item_count; /* total # of MRs */
atomic_t dirty_count; /* # dirty of MRs */
- struct xlist_head drop_list; /* MRs that have reached their max_maps limit */
- struct xlist_head free_list; /* unused MRs */
- struct xlist_head clean_list; /* global unused & unamapped MRs */
+ struct llist_head drop_list; /* MRs that have reached their max_maps limit */
+ struct llist_head free_list; /* unused MRs */
+ struct llist_head clean_list; /* global unused & unamapped MRs */
wait_queue_head_t flush_wait;
atomic_t free_pinned; /* memory pinned by free MRs */
@@ -220,9 +220,9 @@
if (!pool)
return ERR_PTR(-ENOMEM);
- INIT_XLIST_HEAD(&pool->free_list);
- INIT_XLIST_HEAD(&pool->drop_list);
- INIT_XLIST_HEAD(&pool->clean_list);
+ init_llist_head(&pool->free_list);
+ init_llist_head(&pool->drop_list);
+ init_llist_head(&pool->clean_list);
mutex_init(&pool->flush_lock);
init_waitqueue_head(&pool->flush_wait);
INIT_DELAYED_WORK(&pool->flush_worker, rds_ib_mr_pool_flush_worker);
@@ -260,26 +260,18 @@
kfree(pool);
}
-static void refill_local(struct rds_ib_mr_pool *pool, struct xlist_head *xl,
- struct rds_ib_mr **ibmr_ret)
-{
- struct xlist_head *ibmr_xl;
- ibmr_xl = xlist_del_head_fast(xl);
- *ibmr_ret = list_entry(ibmr_xl, struct rds_ib_mr, xlist);
-}
-
static inline struct rds_ib_mr *rds_ib_reuse_fmr(struct rds_ib_mr_pool *pool)
{
struct rds_ib_mr *ibmr = NULL;
- struct xlist_head *ret;
+ struct llist_node *ret;
unsigned long *flag;
preempt_disable();
flag = &__get_cpu_var(clean_list_grace);
set_bit(CLEAN_LIST_BUSY_BIT, flag);
- ret = xlist_del_head(&pool->clean_list);
+ ret = llist_del_first(&pool->clean_list);
if (ret)
- ibmr = list_entry(ret, struct rds_ib_mr, xlist);
+ ibmr = llist_entry(ret, struct rds_ib_mr, llnode);
clear_bit(CLEAN_LIST_BUSY_BIT, flag);
preempt_enable();
@@ -529,46 +521,44 @@
}
/*
- * given an xlist of mrs, put them all into the list_head for more processing
+ * given an llist of mrs, put them all into the list_head for more processing
*/
-static void xlist_append_to_list(struct xlist_head *xlist, struct list_head *list)
+static void llist_append_to_list(struct llist_head *llist, struct list_head *list)
{
struct rds_ib_mr *ibmr;
- struct xlist_head splice;
- struct xlist_head *cur;
- struct xlist_head *next;
+ struct llist_node *node;
+ struct llist_node *next;
- splice.next = NULL;
- xlist_splice(xlist, &splice);
- cur = splice.next;
- while (cur) {
- next = cur->next;
- ibmr = list_entry(cur, struct rds_ib_mr, xlist);
+ node = llist_del_all(llist);
+ while (node) {
+ next = node->next;
+ ibmr = llist_entry(node, struct rds_ib_mr, llnode);
list_add_tail(&ibmr->unmap_list, list);
- cur = next;
+ node = next;
}
}
/*
- * this takes a list head of mrs and turns it into an xlist of clusters.
- * each cluster has an xlist of MR_CLUSTER_SIZE mrs that are ready for
- * reuse.
+ * this takes a list head of mrs and turns it into linked llist nodes
+ * of clusters. Each cluster has linked llist nodes of
+ * MR_CLUSTER_SIZE mrs that are ready for reuse.
*/
-static void list_append_to_xlist(struct rds_ib_mr_pool *pool,
- struct list_head *list, struct xlist_head *xlist,
- struct xlist_head **tail_ret)
+static void list_to_llist_nodes(struct rds_ib_mr_pool *pool,
+ struct list_head *list,
+ struct llist_node **nodes_head,
+ struct llist_node **nodes_tail)
{
struct rds_ib_mr *ibmr;
- struct xlist_head *cur_mr = xlist;
- struct xlist_head *tail_mr = NULL;
+ struct llist_node *cur = NULL;
+ struct llist_node **next = nodes_head;
list_for_each_entry(ibmr, list, unmap_list) {
- tail_mr = &ibmr->xlist;
- tail_mr->next = NULL;
- cur_mr->next = tail_mr;
- cur_mr = tail_mr;
+ cur = &ibmr->llnode;
+ *next = cur;
+ next = &cur->next;
}
- *tail_ret = tail_mr;
+ *next = NULL;
+ *nodes_tail = cur;
}
/*
@@ -581,8 +571,8 @@
int free_all, struct rds_ib_mr **ibmr_ret)
{
struct rds_ib_mr *ibmr, *next;
- struct xlist_head clean_xlist;
- struct xlist_head *clean_tail;
+ struct llist_node *clean_nodes;
+ struct llist_node *clean_tail;
LIST_HEAD(unmap_list);
LIST_HEAD(fmr_list);
unsigned long unpinned = 0;
@@ -603,7 +593,7 @@
prepare_to_wait(&pool->flush_wait, &wait,
TASK_UNINTERRUPTIBLE);
- if (xlist_empty(&pool->clean_list))
+ if (llist_empty(&pool->clean_list))
schedule();
ibmr = rds_ib_reuse_fmr(pool);
@@ -628,10 +618,10 @@
/* Get the list of all MRs to be dropped. Ordering matters -
* we want to put drop_list ahead of free_list.
*/
- xlist_append_to_list(&pool->drop_list, &unmap_list);
- xlist_append_to_list(&pool->free_list, &unmap_list);
+ llist_append_to_list(&pool->drop_list, &unmap_list);
+ llist_append_to_list(&pool->free_list, &unmap_list);
if (free_all)
- xlist_append_to_list(&pool->clean_list, &unmap_list);
+ llist_append_to_list(&pool->clean_list, &unmap_list);
free_goal = rds_ib_flush_goal(pool, free_all);
@@ -663,22 +653,22 @@
if (!list_empty(&unmap_list)) {
/* we have to make sure that none of the things we're about
* to put on the clean list would race with other cpus trying
- * to pull items off. The xlist would explode if we managed to
+ * to pull items off. The llist would explode if we managed to
* remove something from the clean list and then add it back again
- * while another CPU was spinning on that same item in xlist_del_head.
+ * while another CPU was spinning on that same item in llist_del_first.
*
- * This is pretty unlikely, but just in case wait for an xlist grace period
+ * This is pretty unlikely, but just in case wait for an llist grace period
* here before adding anything back into the clean list.
*/
wait_clean_list_grace();
- list_append_to_xlist(pool, &unmap_list, &clean_xlist, &clean_tail);
+ list_to_llist_nodes(pool, &unmap_list, &clean_nodes, &clean_tail);
if (ibmr_ret)
- refill_local(pool, &clean_xlist, ibmr_ret);
+ *ibmr_ret = llist_entry(clean_nodes, struct rds_ib_mr, llnode);
- /* refill_local may have emptied our list */
- if (!xlist_empty(&clean_xlist))
- xlist_add(clean_xlist.next, clean_tail, &pool->clean_list);
+ /* more than one entry in llist nodes */
+ if (clean_nodes->next)
+ llist_add_batch(clean_nodes->next, clean_tail, &pool->clean_list);
}
@@ -711,9 +701,9 @@
/* Return it to the pool's free list */
if (ibmr->remap_count >= pool->fmr_attr.max_maps)
- xlist_add(&ibmr->xlist, &ibmr->xlist, &pool->drop_list);
+ llist_add(&ibmr->llnode, &pool->drop_list);
else
- xlist_add(&ibmr->xlist, &ibmr->xlist, &pool->free_list);
+ llist_add(&ibmr->llnode, &pool->free_list);
atomic_add(ibmr->sg_len, &pool->free_pinned);
atomic_inc(&pool->dirty_count);