RDS: push FMR pool flush work to its own worker

RDS FMR flush operation and also it races with connect/reconect
which happes a lot with RDS. FMR flush being on common rds_wq aggrevates
the problem. Lets push RDS FMR pool flush work to its own worker.

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.c b/net/rds/ib.c
index 13814227b3b235e4b9c924c1eab03859b04cc1f5..d020fade312ce3608def5ecc9ed19939d349e9a5 100644 (file)
--- a/net/rds/ib.c
+++ b/net/rds/ib.c
@@ -366,6 +366,7 @@ void rds_ib_exit(void)
        rds_ib_sysctl_exit();
        rds_ib_recv_exit();
        rds_trans_unregister(&rds_ib_transport);
+       rds_ib_fmr_exit();
 }
 
 struct rds_transport rds_ib_transport = {
@@ -401,10 +402,14 @@ int rds_ib_init(void)
 
        INIT_LIST_HEAD(&rds_ib_devices);
 
-       ret = ib_register_client(&rds_ib_client);
+       ret = rds_ib_fmr_init();
        if (ret)
                goto out;
 
+       ret = ib_register_client(&rds_ib_client);
+       if (ret)
+               goto out_fmr_exit;
+
        ret = rds_ib_sysctl_init();
        if (ret)
                goto out_ibreg;
@@ -427,6 +432,8 @@ out_sysctl:
        rds_ib_sysctl_exit();
 out_ibreg:
        rds_ib_unregister_client();
+out_fmr_exit:
+       rds_ib_fmr_exit();
 out:
        return ret;
 }

diff --git a/net/rds/ib.h b/net/rds/ib.h
index 6422c52682e56e679cd38ccc634285f3f7f27b27..9fc95e38659a40fdabd679ba2a914591ad774208 100644 (file)
--- a/net/rds/ib.h
+++ b/net/rds/ib.h
@@ -313,6 +313,8 @@ void *rds_ib_get_mr(struct scatterlist *sg, unsigned long nents,
 void rds_ib_sync_mr(void *trans_private, int dir);
 void rds_ib_free_mr(void *trans_private, int invalidate);
 void rds_ib_flush_mrs(void);
+int rds_ib_fmr_init(void);
+void rds_ib_fmr_exit(void);
 
 /* ib_recv.c */
 int rds_ib_recv_init(void);

diff --git a/net/rds/ib_rdma.c b/net/rds/ib_rdma.c
index a275b7d205ef4393a91944cb367f0338e2a4ea44..2ac78c9879ea22e4f4d005db7b725ef61872a0e8 100644 (file)
--- a/net/rds/ib_rdma.c
+++ b/net/rds/ib_rdma.c
@@ -83,6 +83,25 @@ struct rds_ib_mr_pool {
        struct ib_fmr_attr      fmr_attr;
 };
 
+struct workqueue_struct *rds_ib_fmr_wq;
+
+int rds_ib_fmr_init(void)
+{
+       rds_ib_fmr_wq = create_workqueue("rds_fmr_flushd");
+       if (!rds_ib_fmr_wq)
+               return -ENOMEM;
+       return 0;
+}
+
+/* By the time this is called all the IB devices should have been torn down and
+ * had their pools freed.  As each pool is freed its work struct is waited on,
+ * so the pool flushing work queue should be idle by the time we get here.
+ */
+void rds_ib_fmr_exit(void)
+{
+       destroy_workqueue(rds_ib_fmr_wq);
+}
+
 static int rds_ib_flush_mr_pool(struct rds_ib_mr_pool *pool, int free_all, struct rds_ib_mr **);
 static void rds_ib_teardown_mr(struct rds_ib_mr *ibmr);
 static void rds_ib_mr_pool_flush_worker(struct work_struct *work);
@@ -719,15 +738,17 @@ 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)
-               schedule_delayed_work(&pool->flush_worker, 10);
+               queue_delayed_work(rds_ib_fmr_wq, &pool->flush_worker, 10);
 
        if (invalidate) {
                if (likely(!in_interrupt())) {
                        rds_ib_flush_mr_pool(pool, 0, NULL);
                } else {
                        /* We get here if the user created a MR marked
-                        * as use_once and invalidate at the same time. */
-                       schedule_delayed_work(&pool->flush_worker, 10);
+                        * as use_once and invalidate at the same time.
+                        */
+                       queue_delayed_work(rds_ib_fmr_wq,
+                                          &pool->flush_worker, 10);
                }
        }