RDS: use delayed work for the FMR flushes

Using a delayed work queue helps us make sure a healthy number of FMRs
have queued up over the limit.  It makes for a large improvement in RDMA
iops.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

diff --git a/net/rds/ib_rdma.c b/net/rds/ib_rdma.c
index 8c40391..3a275af 100644 (file)
--- a/net/rds/ib_rdma.c
+++ b/net/rds/ib_rdma.c
@@ -66,7 +66,7 @@ struct rds_ib_mr {
  */
 struct rds_ib_mr_pool {
        struct mutex            flush_lock;             /* serialize fmr invalidate */
-       struct work_struct      flush_worker;           /* flush worker */
+       struct delayed_work     flush_worker;           /* flush worker */
 
        atomic_t                item_count;             /* total # of MRs */
        atomic_t                dirty_count;            /* # dirty of MRs */
@@ -226,7 +226,7 @@ struct rds_ib_mr_pool *rds_ib_create_mr_pool(struct rds_ib_device *rds_ibdev)
        INIT_XLIST_HEAD(&pool->clean_list);
        mutex_init(&pool->flush_lock);
        init_waitqueue_head(&pool->flush_wait);
-       INIT_WORK(&pool->flush_worker, rds_ib_mr_pool_flush_worker);
+       INIT_DELAYED_WORK(&pool->flush_worker, rds_ib_mr_pool_flush_worker);
 
        pool->fmr_attr.max_pages = fmr_message_size;
        pool->fmr_attr.max_maps = rds_ibdev->fmr_max_remaps;
@@ -254,7 +254,7 @@ void rds_ib_get_mr_info(struct rds_ib_device *rds_ibdev, struct rds_info_rdma_co
 
 void rds_ib_destroy_mr_pool(struct rds_ib_mr_pool *pool)
 {
-       cancel_work_sync(&pool->flush_worker);
+       cancel_delayed_work_sync(&pool->flush_worker);
        rds_ib_flush_mr_pool(pool, 1, NULL);
        WARN_ON(atomic_read(&pool->item_count));
        WARN_ON(atomic_read(&pool->free_pinned));
@@ -695,7 +695,7 @@ out_nolock:
 
 static void rds_ib_mr_pool_flush_worker(struct work_struct *work)
 {
-       struct rds_ib_mr_pool *pool = container_of(work, struct rds_ib_mr_pool, flush_worker);
+       struct rds_ib_mr_pool *pool = container_of(work, struct rds_ib_mr_pool, flush_worker.work);
 
        rds_ib_flush_mr_pool(pool, 0, NULL);
 }
@@ -720,7 +720,7 @@ void rds_ib_free_mr(void *trans_private, int invalidate)
        /* If we've pinned too many pages, request a flush */
        if (atomic_read(&pool->free_pinned) >= pool->max_free_pinned ||
            atomic_read(&pool->dirty_count) >= pool->max_items / 10)
-               queue_work(rds_wq, &pool->flush_worker);
+               queue_delayed_work(rds_wq, &pool->flush_worker, 10);
 
        if (invalidate) {
                if (likely(!in_interrupt())) {
@@ -728,7 +728,7 @@ void rds_ib_free_mr(void *trans_private, int invalidate)
                } else {
                        /* We get here if the user created a MR marked
                         * as use_once and invalidate at the same time. */
-                       queue_work(rds_wq, &pool->flush_worker);
+                       queue_delayed_work(rds_wq, &pool->flush_worker, 10);
                }
        }