RDS: fix fmr pool dirty_count

In rds_ib_flush_mr_pool(), dirty_count accounts the clean ones
which is wrong. This can lead to a negative dirty count value.

Lets fix it.

Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/rds/ib_rdma.c b/net/rds/ib_rdma.c
index 7b7aac8cdb560904bdf7140c156d29479e83a6f9..a275b7d205ef4393a91944cb367f0338e2a4ea44 100644 (file)
--- a/net/rds/ib_rdma.c
+++ b/net/rds/ib_rdma.c
@@ -528,11 +528,13 @@ static inline unsigned int rds_ib_flush_goal(struct rds_ib_mr_pool *pool, int fr
 /*
  * given an llist of mrs, put them all into the list_head for more processing
  */
-static void llist_append_to_list(struct llist_head *llist, struct list_head *list)
+static unsigned int llist_append_to_list(struct llist_head *llist,
+                                        struct list_head *list)
 {
        struct rds_ib_mr *ibmr;
        struct llist_node *node;
        struct llist_node *next;
+       unsigned int count = 0;
 
        node = llist_del_all(llist);
        while (node) {
@@ -540,7 +542,9 @@ static void llist_append_to_list(struct llist_head *llist, struct list_head *lis
                ibmr = llist_entry(node, struct rds_ib_mr, llnode);
                list_add_tail(&ibmr->unmap_list, list);
                node = next;
+               count++;
        }
+       return count;
 }
 
 /*
@@ -581,7 +585,7 @@ static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
        LIST_HEAD(unmap_list);
        LIST_HEAD(fmr_list);
        unsigned long unpinned = 0;
-       unsigned int nfreed = 0, ncleaned = 0, free_goal;
+       unsigned int nfreed = 0, dirty_to_clean = 0, free_goal;
        int ret = 0;
 
        rds_ib_stats_inc(s_ib_rdma_mr_pool_flush);
@@ -623,8 +627,8 @@ static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
        /* Get the list of all MRs to be dropped. Ordering matters -
         * we want to put drop_list ahead of free_list.
         */
-       llist_append_to_list(&pool->drop_list, &unmap_list);
-       llist_append_to_list(&pool->free_list, &unmap_list);
+       dirty_to_clean = llist_append_to_list(&pool->drop_list, &unmap_list);
+       dirty_to_clean += llist_append_to_list(&pool->free_list, &unmap_list);
        if (free_all)
                llist_append_to_list(&pool->clean_list, &unmap_list);
 
@@ -652,7 +656,6 @@ static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
                        kfree(ibmr);
                        nfreed++;
                }
-               ncleaned++;
        }
 
        if (!list_empty(&unmap_list)) {
@@ -678,7 +681,7 @@ static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool,
        }
 
        atomic_sub(unpinned, &pool->free_pinned);
-       atomic_sub(ncleaned, &pool->dirty_count);
+       atomic_sub(dirty_to_clean, &pool->dirty_count);
        atomic_sub(nfreed, &pool->item_count);
 
 out: