Merge tag 'nfs-rdma-for-4.20-1' of git://git.linux-nfs.org/projects/a…

…nna/linux-nfs

NFS RDMA client updates for Linux 4.20

Stable bugfixes:
- Reset credit grant properly after a disconnect

Other bugfixes and cleanups:
- xprt_release_rqst_cong is called outside of transport_lock
- Create more MRs at a time and toss out old ones during recovery
- Various improvements to the RDMA connection and disconnection code:
  - Improve naming of trace events, functions, and variables
  - Add documenting comments
  - Fix metrics and stats reporting
- Fix a tracepoint sparse warning

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

include/trace/events/rpcrdma.h

@@ -263,7 +263,7 @@ DECLARE_EVENT_CLASS(xprtrdma_mr,
 );
 
 #define DEFINE_MR_EVENT(name) \
-		DEFINE_EVENT(xprtrdma_mr, name, \
+		DEFINE_EVENT(xprtrdma_mr, xprtrdma_mr_##name, \
 				TP_PROTO( \
 					const struct rpcrdma_mr *mr \
 				), \
@@ -306,7 +306,7 @@ DECLARE_EVENT_CLASS(xprtrdma_cb_event,
  ** Connection events
  **/
 
-TRACE_EVENT(xprtrdma_conn_upcall,
+TRACE_EVENT(xprtrdma_cm_event,
 	TP_PROTO(
 		const struct rpcrdma_xprt *r_xprt,
 		struct rdma_cm_event *event
@@ -377,7 +377,7 @@ DEFINE_RXPRT_EVENT(xprtrdma_reinsert);
 DEFINE_RXPRT_EVENT(xprtrdma_reconnect);
 DEFINE_RXPRT_EVENT(xprtrdma_inject_dsc);
 
-TRACE_EVENT(xprtrdma_qp_error,
+TRACE_EVENT(xprtrdma_qp_event,
 	TP_PROTO(
 		const struct rpcrdma_xprt *r_xprt,
 		const struct ib_event *event
@@ -509,7 +509,7 @@ TRACE_EVENT(xprtrdma_post_send,
 	TP_STRUCT__entry(
 		__field(const void *, req)
 		__field(int, num_sge)
-		__field(bool, signaled)
+		__field(int, signaled)
 		__field(int, status)
 	),
 
@@ -651,11 +651,11 @@ DEFINE_FRWR_DONE_EVENT(xprtrdma_wc_fastreg);
 DEFINE_FRWR_DONE_EVENT(xprtrdma_wc_li);
 DEFINE_FRWR_DONE_EVENT(xprtrdma_wc_li_wake);
 
-DEFINE_MR_EVENT(xprtrdma_localinv);
-DEFINE_MR_EVENT(xprtrdma_dma_map);
-DEFINE_MR_EVENT(xprtrdma_dma_unmap);
-DEFINE_MR_EVENT(xprtrdma_remoteinv);
-DEFINE_MR_EVENT(xprtrdma_recover_mr);
+DEFINE_MR_EVENT(localinv);
+DEFINE_MR_EVENT(map);
+DEFINE_MR_EVENT(unmap);
+DEFINE_MR_EVENT(remoteinv);
+DEFINE_MR_EVENT(recycle);
 
 /**
  ** Reply events

net/sunrpc/xprt.c

@@ -834,17 +834,11 @@ void xprt_connect(struct rpc_task *task)
 
 static void xprt_connect_status(struct rpc_task *task)
 {
-	struct rpc_xprt	*xprt = task->tk_rqstp->rq_xprt;
-
-	if (task->tk_status == 0) {
-		xprt->stat.connect_count++;
-		xprt->stat.connect_time += (long)jiffies - xprt->stat.connect_start;
+	switch (task->tk_status) {
+	case 0:
 		dprintk("RPC: %5u xprt_connect_status: connection established\n",
 				task->tk_pid);
-		return;
-	}
-
-	switch (task->tk_status) {
+		break;
 	case -ECONNREFUSED:
 	case -ECONNRESET:
 	case -ECONNABORTED:
@@ -861,7 +855,7 @@ static void xprt_connect_status(struct rpc_task *task)
 	default:
 		dprintk("RPC: %5u xprt_connect_status: error %d connecting to "
 				"server %s\n", task->tk_pid, -task->tk_status,
-				xprt->servername);
+				task->tk_rqstp->rq_xprt->servername);
 		task->tk_status = -EIO;
 	}
 }

net/sunrpc/xprtrdma/backchannel.c

@@ -53,9 +53,9 @@ static int rpcrdma_bc_setup_reqs(struct rpcrdma_xprt *r_xprt,
 		rqst->rq_xprt = xprt;
 		INIT_LIST_HEAD(&rqst->rq_bc_list);
 		__set_bit(RPC_BC_PA_IN_USE, &rqst->rq_bc_pa_state);
-		spin_lock_bh(&xprt->bc_pa_lock);
+		spin_lock(&xprt->bc_pa_lock);
 		list_add(&rqst->rq_bc_pa_list, &xprt->bc_pa_list);
-		spin_unlock_bh(&xprt->bc_pa_lock);
+		spin_unlock(&xprt->bc_pa_lock);
 
 		size = r_xprt->rx_data.inline_rsize;
 		rb = rpcrdma_alloc_regbuf(size, DMA_TO_DEVICE, GFP_KERNEL);
@@ -230,16 +230,16 @@ void xprt_rdma_bc_destroy(struct rpc_xprt *xprt, unsigned int reqs)
 	struct rpcrdma_xprt *r_xprt = rpcx_to_rdmax(xprt);
 	struct rpc_rqst *rqst, *tmp;
 
-	spin_lock_bh(&xprt->bc_pa_lock);
+	spin_lock(&xprt->bc_pa_lock);
 	list_for_each_entry_safe(rqst, tmp, &xprt->bc_pa_list, rq_bc_pa_list) {
 		list_del(&rqst->rq_bc_pa_list);
-		spin_unlock_bh(&xprt->bc_pa_lock);
+		spin_unlock(&xprt->bc_pa_lock);
 
 		rpcrdma_bc_free_rqst(r_xprt, rqst);
 
-		spin_lock_bh(&xprt->bc_pa_lock);
+		spin_lock(&xprt->bc_pa_lock);
 	}
-	spin_unlock_bh(&xprt->bc_pa_lock);
+	spin_unlock(&xprt->bc_pa_lock);
 }
 
 /**
@@ -257,9 +257,9 @@ void xprt_rdma_bc_free_rqst(struct rpc_rqst *rqst)
 	rpcrdma_recv_buffer_put(req->rl_reply);
 	req->rl_reply = NULL;
 
-	spin_lock_bh(&xprt->bc_pa_lock);
+	spin_lock(&xprt->bc_pa_lock);
 	list_add_tail(&rqst->rq_bc_pa_list, &xprt->bc_pa_list);
-	spin_unlock_bh(&xprt->bc_pa_lock);
+	spin_unlock(&xprt->bc_pa_lock);
 }
 
 /**

net/sunrpc/xprtrdma/fmr_ops.c

@@ -49,46 +49,7 @@ fmr_is_supported(struct rpcrdma_ia *ia)
 	return true;
 }
 
-static int
-fmr_op_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr)
-{
-	static struct ib_fmr_attr fmr_attr = {
-		.max_pages	= RPCRDMA_MAX_FMR_SGES,
-		.max_maps	= 1,
-		.page_shift	= PAGE_SHIFT
-	};
-
-	mr->fmr.fm_physaddrs = kcalloc(RPCRDMA_MAX_FMR_SGES,
-				       sizeof(u64), GFP_KERNEL);
-	if (!mr->fmr.fm_physaddrs)
-		goto out_free;
-
-	mr->mr_sg = kcalloc(RPCRDMA_MAX_FMR_SGES,
-			    sizeof(*mr->mr_sg), GFP_KERNEL);
-	if (!mr->mr_sg)
-		goto out_free;
-
-	sg_init_table(mr->mr_sg, RPCRDMA_MAX_FMR_SGES);
-
-	mr->fmr.fm_mr = ib_alloc_fmr(ia->ri_pd, RPCRDMA_FMR_ACCESS_FLAGS,
-				     &fmr_attr);
-	if (IS_ERR(mr->fmr.fm_mr))
-		goto out_fmr_err;
-
-	INIT_LIST_HEAD(&mr->mr_list);
-	return 0;
-
-out_fmr_err:
-	dprintk("RPC:       %s: ib_alloc_fmr returned %ld\n", __func__,
-		PTR_ERR(mr->fmr.fm_mr));
-
-out_free:
-	kfree(mr->mr_sg);
-	kfree(mr->fmr.fm_physaddrs);
-	return -ENOMEM;
-}
-
-static int
+static void
 __fmr_unmap(struct rpcrdma_mr *mr)
 {
 	LIST_HEAD(l);
@@ -97,13 +58,16 @@ __fmr_unmap(struct rpcrdma_mr *mr)
 	list_add(&mr->fmr.fm_mr->list, &l);
 	rc = ib_unmap_fmr(&l);
 	list_del(&mr->fmr.fm_mr->list);
-	return rc;
+	if (rc)
+		pr_err("rpcrdma: final ib_unmap_fmr for %p failed %i\n",
+		       mr, rc);
 }
 
+/* Release an MR.
+ */
 static void
 fmr_op_release_mr(struct rpcrdma_mr *mr)
 {
-	LIST_HEAD(unmap_list);
 	int rc;
 
 	kfree(mr->fmr.fm_physaddrs);
@@ -112,10 +76,7 @@ fmr_op_release_mr(struct rpcrdma_mr *mr)
 	/* In case this one was left mapped, try to unmap it
 	 * to prevent dealloc_fmr from failing with EBUSY
 	 */
-	rc = __fmr_unmap(mr);
-	if (rc)
-		pr_err("rpcrdma: final ib_unmap_fmr for %p failed %i\n",
-		       mr, rc);
+	__fmr_unmap(mr);
 
 	rc = ib_dealloc_fmr(mr->fmr.fm_mr);
 	if (rc)
@@ -125,40 +86,68 @@ fmr_op_release_mr(struct rpcrdma_mr *mr)
 	kfree(mr);
 }
 
-/* Reset of a single FMR.
+/* MRs are dynamically allocated, so simply clean up and release the MR.
+ * A replacement MR will subsequently be allocated on demand.
  */
 static void
-fmr_op_recover_mr(struct rpcrdma_mr *mr)
+fmr_mr_recycle_worker(struct work_struct *work)
 {
+	struct rpcrdma_mr *mr = container_of(work, struct rpcrdma_mr, mr_recycle);
 	struct rpcrdma_xprt *r_xprt = mr->mr_xprt;
-	int rc;
 
-	/* ORDER: invalidate first */
-	rc = __fmr_unmap(mr);
-	if (rc)
-		goto out_release;
-
-	/* ORDER: then DMA unmap */
-	rpcrdma_mr_unmap_and_put(mr);
+	trace_xprtrdma_mr_recycle(mr);
 
-	r_xprt->rx_stats.mrs_recovered++;
-	return;
-
-out_release:
-	pr_err("rpcrdma: FMR reset failed (%d), %p released\n", rc, mr);
-	r_xprt->rx_stats.mrs_orphaned++;
-
-	trace_xprtrdma_dma_unmap(mr);
+	trace_xprtrdma_mr_unmap(mr);
 	ib_dma_unmap_sg(r_xprt->rx_ia.ri_device,
 			mr->mr_sg, mr->mr_nents, mr->mr_dir);
 
 	spin_lock(&r_xprt->rx_buf.rb_mrlock);
 	list_del(&mr->mr_all);
+	r_xprt->rx_stats.mrs_recycled++;
 	spin_unlock(&r_xprt->rx_buf.rb_mrlock);
-
 	fmr_op_release_mr(mr);
 }
 
+static int
+fmr_op_init_mr(struct rpcrdma_ia *ia, struct rpcrdma_mr *mr)
+{
+	static struct ib_fmr_attr fmr_attr = {
+		.max_pages	= RPCRDMA_MAX_FMR_SGES,
+		.max_maps	= 1,
+		.page_shift	= PAGE_SHIFT
+	};
+
+	mr->fmr.fm_physaddrs = kcalloc(RPCRDMA_MAX_FMR_SGES,
+				       sizeof(u64), GFP_KERNEL);
+	if (!mr->fmr.fm_physaddrs)
+		goto out_free;
+
+	mr->mr_sg = kcalloc(RPCRDMA_MAX_FMR_SGES,
+			    sizeof(*mr->mr_sg), GFP_KERNEL);
+	if (!mr->mr_sg)
+		goto out_free;
+
+	sg_init_table(mr->mr_sg, RPCRDMA_MAX_FMR_SGES);
+
+	mr->fmr.fm_mr = ib_alloc_fmr(ia->ri_pd, RPCRDMA_FMR_ACCESS_FLAGS,
+				     &fmr_attr);
+	if (IS_ERR(mr->fmr.fm_mr))
+		goto out_fmr_err;
+
+	INIT_LIST_HEAD(&mr->mr_list);
+	INIT_WORK(&mr->mr_recycle, fmr_mr_recycle_worker);
+	return 0;
+
+out_fmr_err:
+	dprintk("RPC:       %s: ib_alloc_fmr returned %ld\n", __func__,
+		PTR_ERR(mr->fmr.fm_mr));
+
+out_free:
+	kfree(mr->mr_sg);
+	kfree(mr->fmr.fm_physaddrs);
+	return -ENOMEM;
+}
+
 /* On success, sets:
  *	ep->rep_attr.cap.max_send_wr
  *	ep->rep_attr.cap.max_recv_wr
@@ -187,6 +176,7 @@ fmr_op_open(struct rpcrdma_ia *ia, struct rpcrdma_ep *ep,
 
 	ia->ri_max_segs = max_t(unsigned int, 1, RPCRDMA_MAX_DATA_SEGS /
 				RPCRDMA_MAX_FMR_SGES);
+	ia->ri_max_segs += 2;	/* segments for head and tail buffers */
 	return 0;
 }
 
@@ -244,7 +234,7 @@ fmr_op_map(struct rpcrdma_xprt *r_xprt, struct rpcrdma_mr_seg *seg,
 				     mr->mr_sg, i, mr->mr_dir);
 	if (!mr->mr_nents)
 		goto out_dmamap_err;
-	trace_xprtrdma_dma_map(mr);
+	trace_xprtrdma_mr_map(mr);
 
 	for (i = 0, dma_pages = mr->fmr.fm_physaddrs; i < mr->mr_nents; i++)
 		dma_pages[i] = sg_dma_address(&mr->mr_sg[i]);
@@ -305,13 +295,13 @@ fmr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct list_head *mrs)
 	list_for_each_entry(mr, mrs, mr_list) {
 		dprintk("RPC:       %s: unmapping fmr %p\n",
 			__func__, &mr->fmr);
-		trace_xprtrdma_localinv(mr);
+		trace_xprtrdma_mr_localinv(mr);
 		list_add_tail(&mr->fmr.fm_mr->list, &unmap_list);
 	}
 	r_xprt->rx_stats.local_inv_needed++;
 	rc = ib_unmap_fmr(&unmap_list);
 	if (rc)
-		goto out_reset;
+		goto out_release;
 
 	/* ORDER: Now DMA unmap all of the req's MRs, and return
 	 * them to the free MW list.
@@ -324,21 +314,20 @@ fmr_op_unmap_sync(struct rpcrdma_xprt *r_xprt, struct list_head *mrs)
 
 	return;
 
-out_reset:
+out_release:
 	pr_err("rpcrdma: ib_unmap_fmr failed (%i)\n", rc);
 
 	while (!list_empty(mrs)) {
 		mr = rpcrdma_mr_pop(mrs);
 		list_del(&mr->fmr.fm_mr->list);
-		fmr_op_recover_mr(mr);
+		rpcrdma_mr_recycle(mr);
 	}
 }
 
 const struct rpcrdma_memreg_ops rpcrdma_fmr_memreg_ops = {
 	.ro_map				= fmr_op_map,
 	.ro_send			= fmr_op_send,
 	.ro_unmap_sync			= fmr_op_unmap_sync,
-	.ro_recover_mr			= fmr_op_recover_mr,
 	.ro_open			= fmr_op_open,
 	.ro_maxpages			= fmr_op_maxpages,
 	.ro_init_mr			= fmr_op_init_mr,