[PATCH v1 0/6] Server-side completion IDs

[PATCH v1 0/6] Server-side completion IDs

[Chuck Lever]

I'd like to remove the display and storage of kernel memory
addresses from the RPC/RDMA transport's tracepoints. This reduces
the size of trace records and closes a (possibly minor) security
exposure.

This series is a down payment on that effort. A similar series is
in the works for the client side transport implementation.

---

Chuck Lever (6):
      svcrdma: Introduce infrastructure to support completion IDs
      svcrdma: Introduce Receive completion IDs
      svcrdma: Record Receive completion ID in svc_rdma_decode_rqst
      svcrdma: Introduce Send completion IDs
      svcrdma: Record send_ctxt completion ID in trace_svcrdma_post_send()
      svcrdma: Display chunk completion ID when posting a rw_ctxt


 include/linux/sunrpc/svc_rdma.h            |   9 +-
 include/trace/events/rpcrdma.h             | 161 +++++++++------------
 net/sunrpc/xprtrdma/svc_rdma_backchannel.c |   2 +-
 net/sunrpc/xprtrdma/svc_rdma_recvfrom.c    |  27 ++--
 net/sunrpc/xprtrdma/svc_rdma_rw.c          |  14 +-
 net/sunrpc/xprtrdma/svc_rdma_sendto.c      |  26 +++-
 6 files changed, 128 insertions(+), 111 deletions(-)

--
Chuck Lever

[PATCH v1 1/6] svcrdma: Introduce infrastructure to support completion IDs

[Chuck Lever]

The goal is to replace CQE kernel memory addresses in completion-
related tracepoints.

Each completion ID matches an incoming Send or Receive completion
to a Completion Queue and to a previous ib_post_*(). The ID can
then be displayed in an error message or recorded in a trace
record.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 include/linux/sunrpc/rpc_rdma_cid.h |   24 ++++++++++++++++++++
 include/trace/events/rpcrdma.h      |   43 +++++++++++++++++++++++++++++++++++
 2 files changed, 67 insertions(+)
 create mode 100644 include/linux/sunrpc/rpc_rdma_cid.h

diff --git a/include/linux/sunrpc/rpc_rdma_cid.h b/include/linux/sunrpc/rpc_rdma_cid.h
new file mode 100644
index 000000000000..be24ab2baa6a
--- /dev/null
+++ b/include/linux/sunrpc/rpc_rdma_cid.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * * Copyright (c) 2020, Oracle and/or its affiliates.
+ */
+
+#ifndef RPC_RDMA_CID_H
+#define RPC_RDMA_CID_H
+
+/*
+ * The rpc_rdma_cid struct records completion ID information. A
+ * completion ID matches an incoming Send or Receive completion
+ * to a Completion Queue and to a previous ib_post_*(). The ID
+ * can then be displayed in an error message or recorded in a
+ * trace record.
+ *
+ * This struct is shared between the server and client RPC/RDMA
+ * transport implementations.
+ */
+struct rpc_rdma_cid {
+	u32			ci_queue_id;
+	int			ci_completion_id;
+};
+
+#endif	/* RPC_RDMA_CID_H */
diff --git a/include/trace/events/rpcrdma.h b/include/trace/events/rpcrdma.h
index 0eff80dee066..70ab989aa3b7 100644
--- a/include/trace/events/rpcrdma.h
+++ b/include/trace/events/rpcrdma.h
@@ -11,6 +11,7 @@
 #define _TRACE_RPCRDMA_H
 
 #include <linux/scatterlist.h>
+#include <linux/sunrpc/rpc_rdma_cid.h>
 #include <linux/tracepoint.h>
 #include <trace/events/rdma.h>
 
@@ -18,6 +19,48 @@
  ** Event classes
  **/
 
+DECLARE_EVENT_CLASS(rpcrdma_completion_class,
+	TP_PROTO(
+		const struct ib_wc *wc,
+		const struct rpc_rdma_cid *cid
+	),
+
+	TP_ARGS(wc, cid),
+
+	TP_STRUCT__entry(
+		__field(u32, cq_id)
+		__field(int, completion_id)
+		__field(unsigned long, status)
+		__field(unsigned int, vendor_err)
+	),
+
+	TP_fast_assign(
+		__entry->cq_id = cid->ci_queue_id;
+		__entry->completion_id = cid->ci_completion_id;
+		__entry->status = wc->status;
+		if (wc->status)
+			__entry->vendor_err = wc->vendor_err;
+		else
+			__entry->vendor_err = 0;
+	),
+
+	TP_printk("cq.id=%u cid=%d status=%s (%lu/0x%x)",
+		__entry->cq_id, __entry->completion_id,
+		rdma_show_wc_status(__entry->status),
+		__entry->status, __entry->vendor_err
+	)
+);
+
+#define DEFINE_COMPLETION_EVENT(name)					\
+		DEFINE_EVENT(rpcrdma_completion_class, name,		\
+				TP_PROTO(				\
+					const struct ib_wc *wc,		\
+					const struct rpc_rdma_cid *cid	\
+				),					\
+				TP_ARGS(wc, cid))
+
+DEFINE_COMPLETION_EVENT(dummy);
+
 DECLARE_EVENT_CLASS(xprtrdma_reply_event,
 	TP_PROTO(
 		const struct rpcrdma_rep *rep

[PATCH v1 2/6] svcrdma: Introduce Receive completion IDs

[Chuck Lever]

Set up a completion ID in each svc_rdma_recv_ctxt. The ID is used
to match an incoming Receive completion to a transport and to a
previous ib_post_recv().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 include/linux/sunrpc/svc_rdma.h         |    4 ++
 include/trace/events/rpcrdma.h          |   51 ++++++++++++-------------------
 net/sunrpc/xprtrdma/svc_rdma_recvfrom.c |   15 +++++++--
 3 files changed, 36 insertions(+), 34 deletions(-)

diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h
index d28ca1b6f2eb..c3c1e46f510f 100644
--- a/include/linux/sunrpc/svc_rdma.h
+++ b/include/linux/sunrpc/svc_rdma.h
@@ -46,6 +46,7 @@
 #include <linux/sunrpc/xdr.h>
 #include <linux/sunrpc/svcsock.h>
 #include <linux/sunrpc/rpc_rdma.h>
+#include <linux/sunrpc/rpc_rdma_cid.h>
 #include <rdma/ib_verbs.h>
 #include <rdma/rdma_cm.h>
 
@@ -109,6 +110,8 @@ struct svcxprt_rdma {
 	struct work_struct   sc_work;
 
 	struct llist_head    sc_recv_ctxts;
+
+	atomic_t	     sc_completion_ids;
 };
 /* sc_flags */
 #define RDMAXPRT_CONN_PENDING	3
@@ -129,6 +132,7 @@ struct svc_rdma_recv_ctxt {
 	struct list_head	rc_list;
 	struct ib_recv_wr	rc_recv_wr;
 	struct ib_cqe		rc_cqe;
+	struct rpc_rdma_cid	rc_cid;
 	struct ib_sge		rc_recv_sge;
 	void			*rc_recv_buf;
 	struct xdr_buf		rc_arg;
diff --git a/include/trace/events/rpcrdma.h b/include/trace/events/rpcrdma.h
index 70ab989aa3b7..a0330a557e34 100644
--- a/include/trace/events/rpcrdma.h
+++ b/include/trace/events/rpcrdma.h
@@ -59,8 +59,6 @@ DECLARE_EVENT_CLASS(rpcrdma_completion_class,
 				),					\
 				TP_ARGS(wc, cid))
 
-DEFINE_COMPLETION_EVENT(dummy);
-
 DECLARE_EVENT_CLASS(xprtrdma_reply_event,
 	TP_PROTO(
 		const struct rpcrdma_rep *rep
@@ -1849,57 +1847,48 @@ DEFINE_SENDCOMP_EVENT(send);
 
 TRACE_EVENT(svcrdma_post_recv,
 	TP_PROTO(
-		const struct ib_recv_wr *wr,
-		int status
+		const struct svc_rdma_recv_ctxt *ctxt
 	),
 
-	TP_ARGS(wr, status),
+	TP_ARGS(ctxt),
 
 	TP_STRUCT__entry(
-		__field(const void *, cqe)
-		__field(int, status)
+		__field(u32, cq_id)
+		__field(int, completion_id)
 	),
 
 	TP_fast_assign(
-		__entry->cqe = wr->wr_cqe;
-		__entry->status = status;
+		__entry->cq_id = ctxt->rc_cid.ci_queue_id;
+		__entry->completion_id = ctxt->rc_cid.ci_completion_id;
 	),
 
-	TP_printk("cqe=%p status=%d",
-		__entry->cqe, __entry->status
+	TP_printk("cq.id=%d cid=%d",
+		__entry->cq_id, __entry->completion_id
 	)
 );
 
-TRACE_EVENT(svcrdma_wc_receive,
+DEFINE_COMPLETION_EVENT(svcrdma_wc_receive);
+
+TRACE_EVENT(svcrdma_rq_post_err,
 	TP_PROTO(
-		const struct ib_wc *wc
+		const struct svcxprt_rdma *rdma,
+		int status
 	),
 
-	TP_ARGS(wc),
+	TP_ARGS(rdma, status),
 
 	TP_STRUCT__entry(
-		__field(const void *, cqe)
-		__field(u32, byte_len)
-		__field(unsigned int, status)
-		__field(u32, vendor_err)
+		__field(int, status)
+		__string(addr, rdma->sc_xprt.xpt_remotebuf)
 	),
 
 	TP_fast_assign(
-		__entry->cqe = wc->wr_cqe;
-		__entry->status = wc->status;
-		if (wc->status) {
-			__entry->byte_len = 0;
-			__entry->vendor_err = wc->vendor_err;
-		} else {
-			__entry->byte_len = wc->byte_len;
-			__entry->vendor_err = 0;
-		}
+		__entry->status = status;
+		__assign_str(addr, rdma->sc_xprt.xpt_remotebuf);
 	),
 
-	TP_printk("cqe=%p byte_len=%u status=%s (%u/0x%x)",
-		__entry->cqe, __entry->byte_len,
-		rdma_show_wc_status(__entry->status),
-		__entry->status, __entry->vendor_err
+	TP_printk("addr=%s status=%d",
+		__get_str(addr), __entry->status
 	)
 );
 
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index c0587d3cd389..e6d7401232d2 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -117,6 +117,13 @@ svc_rdma_next_recv_ctxt(struct list_head *list)
 					rc_list);
 }
 
+static void svc_rdma_recv_cid_init(struct svcxprt_rdma *rdma,
+				   struct rpc_rdma_cid *cid)
+{
+	cid->ci_queue_id = rdma->sc_rq_cq->res.id;
+	cid->ci_completion_id = atomic_inc_return(&rdma->sc_completion_ids);
+}
+
 static struct svc_rdma_recv_ctxt *
 svc_rdma_recv_ctxt_alloc(struct svcxprt_rdma *rdma)
 {
@@ -135,6 +142,8 @@ svc_rdma_recv_ctxt_alloc(struct svcxprt_rdma *rdma)
 	if (ib_dma_mapping_error(rdma->sc_pd->device, addr))
 		goto fail2;
 
+	svc_rdma_recv_cid_init(rdma, &ctxt->rc_cid);
+
 	ctxt->rc_recv_wr.next = NULL;
 	ctxt->rc_recv_wr.wr_cqe = &ctxt->rc_cqe;
 	ctxt->rc_recv_wr.sg_list = &ctxt->rc_recv_sge;
@@ -249,13 +258,14 @@ static int __svc_rdma_post_recv(struct svcxprt_rdma *rdma,
 	int ret;
 
 	svc_xprt_get(&rdma->sc_xprt);
+	trace_svcrdma_post_recv(ctxt);
 	ret = ib_post_recv(rdma->sc_qp, &ctxt->rc_recv_wr, NULL);
-	trace_svcrdma_post_recv(&ctxt->rc_recv_wr, ret);
 	if (ret)
 		goto err_post;
 	return 0;
 
 err_post:
+	trace_svcrdma_rq_post_err(rdma, ret);
 	svc_rdma_recv_ctxt_put(rdma, ctxt);
 	svc_xprt_put(&rdma->sc_xprt);
 	return ret;
@@ -309,11 +319,10 @@ static void svc_rdma_wc_receive(struct ib_cq *cq, struct ib_wc *wc)
 	struct ib_cqe *cqe = wc->wr_cqe;
 	struct svc_rdma_recv_ctxt *ctxt;
 
-	trace_svcrdma_wc_receive(wc);
-
 	/* WARNING: Only wc->wr_cqe and wc->status are reliable */
 	ctxt = container_of(cqe, struct svc_rdma_recv_ctxt, rc_cqe);
 
+	trace_svcrdma_wc_receive(wc, &ctxt->rc_cid);
 	if (wc->status != IB_WC_SUCCESS)
 		goto flushed;
 

[PATCH v1 3/6] svcrdma: Record Receive completion ID in svc_rdma_decode_rqst

[Chuck Lever]

When recording a trace event in the Receive path, tie decoding
results and errors to an incoming Receive completion.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 include/trace/events/rpcrdma.h          |   34 +++++++++++++++++++++++++------
 net/sunrpc/xprtrdma/svc_rdma_recvfrom.c |   12 +++++------
 2 files changed, 33 insertions(+), 13 deletions(-)

diff --git a/include/trace/events/rpcrdma.h b/include/trace/events/rpcrdma.h
index a0330a557e34..df49ae5d447b 100644
--- a/include/trace/events/rpcrdma.h
+++ b/include/trace/events/rpcrdma.h
@@ -1369,13 +1369,16 @@ TRACE_DEFINE_ENUM(RDMA_ERROR);
 
 TRACE_EVENT(svcrdma_decode_rqst,
 	TP_PROTO(
+		const struct svc_rdma_recv_ctxt *ctxt,
 		__be32 *p,
 		unsigned int hdrlen
 	),
 
-	TP_ARGS(p, hdrlen),
+	TP_ARGS(ctxt, p, hdrlen),
 
 	TP_STRUCT__entry(
+		__field(u32, cq_id)
+		__field(int, completion_id)
 		__field(u32, xid)
 		__field(u32, vers)
 		__field(u32, proc)
@@ -1384,6 +1387,8 @@ TRACE_EVENT(svcrdma_decode_rqst,
 	),
 
 	TP_fast_assign(
+		__entry->cq_id = ctxt->rc_cid.ci_queue_id;
+		__entry->completion_id = ctxt->rc_cid.ci_completion_id;
 		__entry->xid = be32_to_cpup(p++);
 		__entry->vers = be32_to_cpup(p++);
 		__entry->credits = be32_to_cpup(p++);
@@ -1391,37 +1396,48 @@ TRACE_EVENT(svcrdma_decode_rqst,
 		__entry->hdrlen = hdrlen;
 	),
 
-	TP_printk("xid=0x%08x vers=%u credits=%u proc=%s hdrlen=%u",
+	TP_printk("cq.id=%u cid=%d xid=0x%08x vers=%u credits=%u proc=%s hdrlen=%u",
+		__entry->cq_id, __entry->completion_id,
 		__entry->xid, __entry->vers, __entry->credits,
 		show_rpcrdma_proc(__entry->proc), __entry->hdrlen)
 );
 
 TRACE_EVENT(svcrdma_decode_short_err,
 	TP_PROTO(
+		const struct svc_rdma_recv_ctxt *ctxt,
 		unsigned int hdrlen
 	),
 
-	TP_ARGS(hdrlen),
+	TP_ARGS(ctxt, hdrlen),
 
 	TP_STRUCT__entry(
+		__field(u32, cq_id)
+		__field(int, completion_id)
 		__field(unsigned int, hdrlen)
 	),
 
 	TP_fast_assign(
+		__entry->cq_id = ctxt->rc_cid.ci_queue_id;
+		__entry->completion_id = ctxt->rc_cid.ci_completion_id;
 		__entry->hdrlen = hdrlen;
 	),
 
-	TP_printk("hdrlen=%u", __entry->hdrlen)
+	TP_printk("cq.id=%u cid=%d hdrlen=%u",
+		__entry->cq_id, __entry->completion_id,
+		__entry->hdrlen)
 );
 
 DECLARE_EVENT_CLASS(svcrdma_badreq_event,
 	TP_PROTO(
+		const struct svc_rdma_recv_ctxt *ctxt,
 		__be32 *p
 	),
 
-	TP_ARGS(p),
+	TP_ARGS(ctxt, p),
 
 	TP_STRUCT__entry(
+		__field(u32, cq_id)
+		__field(int, completion_id)
 		__field(u32, xid)
 		__field(u32, vers)
 		__field(u32, proc)
@@ -1429,13 +1445,16 @@ DECLARE_EVENT_CLASS(svcrdma_badreq_event,
 	),
 
 	TP_fast_assign(
+		__entry->cq_id = ctxt->rc_cid.ci_queue_id;
+		__entry->completion_id = ctxt->rc_cid.ci_completion_id;
 		__entry->xid = be32_to_cpup(p++);
 		__entry->vers = be32_to_cpup(p++);
 		__entry->credits = be32_to_cpup(p++);
 		__entry->proc = be32_to_cpup(p);
 	),
 
-	TP_printk("xid=0x%08x vers=%u credits=%u proc=%u",
+	TP_printk("cq.id=%u cid=%d xid=0x%08x vers=%u credits=%u proc=%u",
+		__entry->cq_id, __entry->completion_id,
 		__entry->xid, __entry->vers, __entry->credits, __entry->proc)
 );
 
@@ -1443,9 +1462,10 @@ DECLARE_EVENT_CLASS(svcrdma_badreq_event,
 		DEFINE_EVENT(svcrdma_badreq_event,			\
 			     svcrdma_decode_##name##_err,		\
 				TP_PROTO(				\
+					const struct svc_rdma_recv_ctxt *ctxt,	\
 					__be32 *p			\
 				),					\
-				TP_ARGS(p))
+				TP_ARGS(ctxt, p))
 
 DEFINE_BADREQ_EVENT(badvers);
 DEFINE_BADREQ_EVENT(drop);
diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
index e6d7401232d2..d5ec85cb652c 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c
@@ -667,27 +667,27 @@ static int svc_rdma_xdr_decode_req(struct xdr_buf *rq_arg,
 	hdr_len = xdr_stream_pos(&rctxt->rc_stream);
 	rq_arg->head[0].iov_len -= hdr_len;
 	rq_arg->len -= hdr_len;
-	trace_svcrdma_decode_rqst(rdma_argp, hdr_len);
+	trace_svcrdma_decode_rqst(rctxt, rdma_argp, hdr_len);
 	return hdr_len;
 
 out_short:
-	trace_svcrdma_decode_short_err(rq_arg->len);
+	trace_svcrdma_decode_short_err(rctxt, rq_arg->len);
 	return -EINVAL;
 
 out_version:
-	trace_svcrdma_decode_badvers_err(rdma_argp);
+	trace_svcrdma_decode_badvers_err(rctxt, rdma_argp);
 	return -EPROTONOSUPPORT;
 
 out_drop:
-	trace_svcrdma_decode_drop_err(rdma_argp);
+	trace_svcrdma_decode_drop_err(rctxt, rdma_argp);
 	return 0;
 
 out_proc:
-	trace_svcrdma_decode_badproc_err(rdma_argp);
+	trace_svcrdma_decode_badproc_err(rctxt, rdma_argp);
 	return -EINVAL;
 
 out_inval:
-	trace_svcrdma_decode_parse_err(rdma_argp);
+	trace_svcrdma_decode_parse_err(rctxt, rdma_argp);
 	return -EINVAL;
 }
 

[PATCH v1 4/6] svcrdma: Introduce Send completion IDs

[Chuck Lever]

Set up a completion ID in each svc_rdma_send_ctxt. The ID is used
to match an incoming Send completion to a transport and to a
previous ib_post_send().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 include/linux/sunrpc/svc_rdma.h       |    2 ++
 include/trace/events/rpcrdma.h        |    2 +-
 net/sunrpc/xprtrdma/svc_rdma_sendto.c |   15 ++++++++++++---
 3 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h
index c3c1e46f510f..c91e00bc937e 100644
--- a/include/linux/sunrpc/svc_rdma.h
+++ b/include/linux/sunrpc/svc_rdma.h
@@ -151,6 +151,8 @@ struct svc_rdma_recv_ctxt {
 
 struct svc_rdma_send_ctxt {
 	struct list_head	sc_list;
+	struct rpc_rdma_cid	sc_cid;
+
 	struct ib_send_wr	sc_send_wr;
 	struct ib_cqe		sc_cqe;
 	struct xdr_buf		sc_hdrbuf;
diff --git a/include/trace/events/rpcrdma.h b/include/trace/events/rpcrdma.h
index df49ae5d447b..782a4d826a4b 100644
--- a/include/trace/events/rpcrdma.h
+++ b/include/trace/events/rpcrdma.h
@@ -1863,7 +1863,7 @@ TRACE_EVENT(svcrdma_post_send,
 	)
 );
 
-DEFINE_SENDCOMP_EVENT(send);
+DEFINE_COMPLETION_EVENT(svcrdma_wc_send);
 
 TRACE_EVENT(svcrdma_post_recv,
 	TP_PROTO(
diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
index 38d8f0ee35ec..c720dcf56231 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -122,6 +122,13 @@ svc_rdma_next_send_ctxt(struct list_head *list)
 					sc_list);
 }
 
+static void svc_rdma_send_cid_init(struct svcxprt_rdma *rdma,
+				   struct rpc_rdma_cid *cid)
+{
+	cid->ci_queue_id = rdma->sc_sq_cq->res.id;
+	cid->ci_completion_id = atomic_inc_return(&rdma->sc_completion_ids);
+}
+
 static struct svc_rdma_send_ctxt *
 svc_rdma_send_ctxt_alloc(struct svcxprt_rdma *rdma)
 {
@@ -144,6 +151,8 @@ svc_rdma_send_ctxt_alloc(struct svcxprt_rdma *rdma)
 	if (ib_dma_mapping_error(rdma->sc_pd->device, addr))
 		goto fail2;
 
+	svc_rdma_send_cid_init(rdma, &ctxt->sc_cid);
+
 	ctxt->sc_send_wr.next = NULL;
 	ctxt->sc_send_wr.wr_cqe = &ctxt->sc_cqe;
 	ctxt->sc_send_wr.sg_list = ctxt->sc_sges;
@@ -268,14 +277,14 @@ static void svc_rdma_wc_send(struct ib_cq *cq, struct ib_wc *wc)
 {
 	struct svcxprt_rdma *rdma = cq->cq_context;
 	struct ib_cqe *cqe = wc->wr_cqe;
-	struct svc_rdma_send_ctxt *ctxt;
+	struct svc_rdma_send_ctxt *ctxt =
+		container_of(cqe, struct svc_rdma_send_ctxt, sc_cqe);
 
-	trace_svcrdma_wc_send(wc);
+	trace_svcrdma_wc_send(wc, &ctxt->sc_cid);
 
 	atomic_inc(&rdma->sc_sq_avail);
 	wake_up(&rdma->sc_send_wait);
 
-	ctxt = container_of(cqe, struct svc_rdma_send_ctxt, sc_cqe);
 	svc_rdma_send_ctxt_put(rdma, ctxt);
 
 	if (unlikely(wc->status != IB_WC_SUCCESS)) {

[PATCH v1 5/6] svcrdma: Record send_ctxt completion ID in trace_svcrdma_post_send()

[Chuck Lever]

First, refactor: Dereference the svc_rdma_send_ctxt inside
svc_rdma_send() instead of at every call site.

Then, it can be passed into trace_svcrdma_post_send() to get the
proper completion ID.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 include/linux/sunrpc/svc_rdma.h            |    3 ++-
 include/trace/events/rpcrdma.h             |   18 +++++++++++-------
 net/sunrpc/xprtrdma/svc_rdma_backchannel.c |    2 +-
 net/sunrpc/xprtrdma/svc_rdma_sendto.c      |   11 ++++++-----
 4 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h
index c91e00bc937e..9dc3a3b88391 100644
--- a/include/linux/sunrpc/svc_rdma.h
+++ b/include/linux/sunrpc/svc_rdma.h
@@ -196,7 +196,8 @@ extern struct svc_rdma_send_ctxt *
 		svc_rdma_send_ctxt_get(struct svcxprt_rdma *rdma);
 extern void svc_rdma_send_ctxt_put(struct svcxprt_rdma *rdma,
 				   struct svc_rdma_send_ctxt *ctxt);
-extern int svc_rdma_send(struct svcxprt_rdma *rdma, struct ib_send_wr *wr);
+extern int svc_rdma_send(struct svcxprt_rdma *rdma,
+			 struct svc_rdma_send_ctxt *ctxt);
 extern int svc_rdma_map_reply_msg(struct svcxprt_rdma *rdma,
 				  struct svc_rdma_send_ctxt *sctxt,
 				  const struct svc_rdma_recv_ctxt *rctxt,
diff --git a/include/trace/events/rpcrdma.h b/include/trace/events/rpcrdma.h
index 782a4d826a4b..aeeba9188ed5 100644
--- a/include/trace/events/rpcrdma.h
+++ b/include/trace/events/rpcrdma.h
@@ -1839,27 +1839,31 @@ DECLARE_EVENT_CLASS(svcrdma_sendcomp_event,
 
 TRACE_EVENT(svcrdma_post_send,
 	TP_PROTO(
-		const struct ib_send_wr *wr
+		const struct svc_rdma_send_ctxt *ctxt
 	),
 
-	TP_ARGS(wr),
+	TP_ARGS(ctxt),
 
 	TP_STRUCT__entry(
-		__field(const void *, cqe)
+		__field(u32, cq_id)
+		__field(int, completion_id)
 		__field(unsigned int, num_sge)
 		__field(u32, inv_rkey)
 	),
 
 	TP_fast_assign(
-		__entry->cqe = wr->wr_cqe;
+		const struct ib_send_wr *wr = &ctxt->sc_send_wr;
+
+		__entry->cq_id = ctxt->sc_cid.ci_queue_id;
+		__entry->completion_id = ctxt->sc_cid.ci_completion_id;
 		__entry->num_sge = wr->num_sge;
 		__entry->inv_rkey = (wr->opcode == IB_WR_SEND_WITH_INV) ?
 					wr->ex.invalidate_rkey : 0;
 	),
 
-	TP_printk("cqe=%p num_sge=%u inv_rkey=0x%08x",
-		__entry->cqe, __entry->num_sge,
-		__entry->inv_rkey
+	TP_printk("cq_id=%u cid=%d num_sge=%u inv_rkey=0x%08x",
+		__entry->cq_id, __entry->completion_id,
+		__entry->num_sge, __entry->inv_rkey
 	)
 );
 
diff --git a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
index 1ee73f7cf931..5e7c4ba9e147 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
@@ -87,7 +87,7 @@ static int svc_rdma_bc_sendto(struct svcxprt_rdma *rdma,
 	 */
 	get_page(virt_to_page(rqst->rq_buffer));
 	ctxt->sc_send_wr.opcode = IB_WR_SEND;
-	return svc_rdma_send(rdma, &ctxt->sc_send_wr);
+	return svc_rdma_send(rdma, ctxt);
 }
 
 /* Server-side transport endpoint wants a whole page for its send
diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
index c720dcf56231..73d46e8cdc16 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c
@@ -298,13 +298,14 @@ static void svc_rdma_wc_send(struct ib_cq *cq, struct ib_wc *wc)
 /**
  * svc_rdma_send - Post a single Send WR
  * @rdma: transport on which to post the WR
- * @wr: prepared Send WR to post
+ * @ctxt: send ctxt with a Send WR ready to post
  *
  * Returns zero the Send WR was posted successfully. Otherwise, a
  * negative errno is returned.
  */
-int svc_rdma_send(struct svcxprt_rdma *rdma, struct ib_send_wr *wr)
+int svc_rdma_send(struct svcxprt_rdma *rdma, struct svc_rdma_send_ctxt *ctxt)
 {
+	struct ib_send_wr *wr = &ctxt->sc_send_wr;
 	int ret;
 
 	might_sleep();
@@ -330,7 +331,7 @@ int svc_rdma_send(struct svcxprt_rdma *rdma, struct ib_send_wr *wr)
 		}
 
 		svc_xprt_get(&rdma->sc_xprt);
-		trace_svcrdma_post_send(wr);
+		trace_svcrdma_post_send(ctxt);
 		ret = ib_post_send(rdma->sc_qp, wr, NULL);
 		if (ret)
 			break;
@@ -805,7 +806,7 @@ static int svc_rdma_send_reply_msg(struct svcxprt_rdma *rdma,
 	} else {
 		sctxt->sc_send_wr.opcode = IB_WR_SEND;
 	}
-	return svc_rdma_send(rdma, &sctxt->sc_send_wr);
+	return svc_rdma_send(rdma, sctxt);
 }
 
 /**
@@ -869,7 +870,7 @@ void svc_rdma_send_error_msg(struct svcxprt_rdma *rdma,
 	sctxt->sc_send_wr.num_sge = 1;
 	sctxt->sc_send_wr.opcode = IB_WR_SEND;
 	sctxt->sc_sges[0].length = sctxt->sc_hdrbuf.len;
-	if (svc_rdma_send(rdma, &sctxt->sc_send_wr))
+	if (svc_rdma_send(rdma, sctxt))
 		goto put_ctxt;
 	return;
 

[PATCH v1 6/6] svcrdma: Display chunk completion ID when posting a rw_ctxt

[Chuck Lever]

Re-use the post_rw tracepoint (safely) to trace cc_info lifetime
events, including completion IDs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 include/trace/events/rpcrdma.h    |   56 ++++++++-----------------------------
 net/sunrpc/xprtrdma/svc_rdma_rw.c |   14 ++++++++-
 2 files changed, 24 insertions(+), 46 deletions(-)

diff --git a/include/trace/events/rpcrdma.h b/include/trace/events/rpcrdma.h
index aeeba9188ed5..abe942225637 100644
--- a/include/trace/events/rpcrdma.h
+++ b/include/trace/events/rpcrdma.h
@@ -1802,41 +1802,6 @@ TRACE_EVENT(svcrdma_send_err,
 	)
 );
 
-DECLARE_EVENT_CLASS(svcrdma_sendcomp_event,
-	TP_PROTO(
-		const struct ib_wc *wc
-	),
-
-	TP_ARGS(wc),
-
-	TP_STRUCT__entry(
-		__field(const void *, cqe)
-		__field(unsigned int, status)
-		__field(unsigned int, vendor_err)
-	),
-
-	TP_fast_assign(
-		__entry->cqe = wc->wr_cqe;
-		__entry->status = wc->status;
-		if (wc->status)
-			__entry->vendor_err = wc->vendor_err;
-		else
-			__entry->vendor_err = 0;
-	),
-
-	TP_printk("cqe=%p status=%s (%u/0x%x)",
-		__entry->cqe, rdma_show_wc_status(__entry->status),
-		__entry->status, __entry->vendor_err
-	)
-);
-
-#define DEFINE_SENDCOMP_EVENT(name)					\
-		DEFINE_EVENT(svcrdma_sendcomp_event, svcrdma_wc_##name,	\
-				TP_PROTO(				\
-					const struct ib_wc *wc		\
-				),					\
-				TP_ARGS(wc))
-
 TRACE_EVENT(svcrdma_post_send,
 	TP_PROTO(
 		const struct svc_rdma_send_ctxt *ctxt
@@ -1916,31 +1881,34 @@ TRACE_EVENT(svcrdma_rq_post_err,
 	)
 );
 
-TRACE_EVENT(svcrdma_post_rw,
+TRACE_EVENT(svcrdma_post_chunk,
 	TP_PROTO(
-		const void *cqe,
+		const struct rpc_rdma_cid *cid,
 		int sqecount
 	),
 
-	TP_ARGS(cqe, sqecount),
+	TP_ARGS(cid, sqecount),
 
 	TP_STRUCT__entry(
-		__field(const void *, cqe)
+		__field(u32, cq_id)
+		__field(int, completion_id)
 		__field(int, sqecount)
 	),
 
 	TP_fast_assign(
-		__entry->cqe = cqe;
+		__entry->cq_id = cid->ci_queue_id;
+		__entry->completion_id = cid->ci_completion_id;
 		__entry->sqecount = sqecount;
 	),
 
-	TP_printk("cqe=%p sqecount=%d",
-		__entry->cqe, __entry->sqecount
+	TP_printk("cq.id=%u cid=%d sqecount=%d",
+		__entry->cq_id, __entry->completion_id,
+		__entry->sqecount
 	)
 );
 
-DEFINE_SENDCOMP_EVENT(read);
-DEFINE_SENDCOMP_EVENT(write);
+DEFINE_COMPLETION_EVENT(svcrdma_wc_read);
+DEFINE_COMPLETION_EVENT(svcrdma_wc_write);
 
 TRACE_EVENT(svcrdma_qp_error,
 	TP_PROTO(
diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c
index 2038b1b286dd..c16d10601d65 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_rw.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c
@@ -145,15 +145,24 @@ static int svc_rdma_rw_ctx_init(struct svcxprt_rdma *rdma,
  * demand, and not cached.
  */
 struct svc_rdma_chunk_ctxt {
+	struct rpc_rdma_cid	cc_cid;
 	struct ib_cqe		cc_cqe;
 	struct svcxprt_rdma	*cc_rdma;
 	struct list_head	cc_rwctxts;
 	int			cc_sqecount;
 };
 
+static void svc_rdma_cc_cid_init(struct svcxprt_rdma *rdma,
+				 struct rpc_rdma_cid *cid)
+{
+	cid->ci_queue_id = rdma->sc_sq_cq->res.id;
+	cid->ci_completion_id = atomic_inc_return(&rdma->sc_completion_ids);
+}
+
 static void svc_rdma_cc_init(struct svcxprt_rdma *rdma,
 			     struct svc_rdma_chunk_ctxt *cc)
 {
+	svc_rdma_cc_cid_init(rdma, &cc->cc_cid);
 	cc->cc_rdma = rdma;
 	svc_xprt_get(&rdma->sc_xprt);
 
@@ -237,7 +246,7 @@ static void svc_rdma_write_done(struct ib_cq *cq, struct ib_wc *wc)
 	struct svc_rdma_write_info *info =
 			container_of(cc, struct svc_rdma_write_info, wi_cc);
 
-	trace_svcrdma_wc_write(wc);
+	trace_svcrdma_wc_write(wc, &cc->cc_cid);
 
 	atomic_add(cc->cc_sqecount, &rdma->sc_sq_avail);
 	wake_up(&rdma->sc_send_wait);
@@ -295,7 +304,7 @@ static void svc_rdma_wc_read_done(struct ib_cq *cq, struct ib_wc *wc)
 	struct svc_rdma_read_info *info =
 			container_of(cc, struct svc_rdma_read_info, ri_cc);
 
-	trace_svcrdma_wc_read(wc);
+	trace_svcrdma_wc_read(wc, &cc->cc_cid);
 
 	atomic_add(cc->cc_sqecount, &rdma->sc_sq_avail);
 	wake_up(&rdma->sc_send_wait);
@@ -351,6 +360,7 @@ static int svc_rdma_post_chunk_ctxt(struct svc_rdma_chunk_ctxt *cc)
 	do {
 		if (atomic_sub_return(cc->cc_sqecount,
 				      &rdma->sc_sq_avail) > 0) {
+			trace_svcrdma_post_chunk(&cc->cc_cid, cc->cc_sqecount);
 			ret = ib_post_send(rdma->sc_qp, first_wr, &bad_wr);
 			if (ret)
 				break;