[RFC PATCH V6 0/3] nvme-trace: Add support for fabrics command

[RFC PATCH V6 0/3] nvme-trace: Add support for fabrics command

[Minwoo Im]

Hi,

This is 6th series to introduce target-side tracing.  This series
continas codes duplicated with host-side tracing, but it can make us
avoid some disadvantages Christoph pointed out.

The target-side takes struct nvmet_req *req, so that those two entries
have a little bit different from host-side tracing entries.

The following logs are examples of this patch series when trying to
connect the loop targeted device:
            nvme-2401  [006] ....  1474.570779: nvmet_req_init: nvme0: qid=0, cmdid=0, nsid=1, flags=0x40, meta=0x0, cmd=(nvme_fabrics_type_connect recfmt=0, qid=0, sqsize=31, cattr=0, kato=15000)
     kworker/6:2-1067  [006] ....  1474.570933: nvmet_req_complete: nvme1: qid=0, cmdid=0, res=0x1, status=0x0
            nvme-2401  [004] ....  1474.571216: nvmet_req_init: nvme1: qid=0, cmdid=6, nsid=4, flags=0x40, meta=0x0, cmd=(nvme_fabrics_type_property_get attrib=1, ofst=0x0)
     kworker/4:2-1235  [004] ....  1474.571336: nvmet_req_complete: nvme1: qid=0, cmdid=6, res=0x200f0003ff, status=0x0
            nvme-2401  [006] ....  1474.571440: nvmet_req_init: nvme1: qid=0, cmdid=22, nsid=0, flags=0x40, meta=0x0, cmd=(nvme_fabrics_type_property_set attrib=0, ofst=0x14, value=0x460001)
     kworker/6:2-1067  [006] ....  1474.571494: nvmet_req_complete: nvme1: qid=0, cmdid=22, res=0x0, status=0x0
            nvme-2401  [004] ....  1474.571668: nvmet_req_init: nvme1: qid=0, cmdid=7, nsid=4, flags=0x40, meta=0x0, cmd=(nvme_fabrics_type_property_get attrib=0, ofst=0x1c)
     kworker/4:2-1235  [004] ....  1474.571767: nvmet_req_complete: nvme1: qid=0, cmdid=7, res=0x1, status=0x0
            nvme-2401  [006] ....  1474.572078: nvmet_req_init: nvme1: qid=0, cmdid=23, nsid=4, flags=0x40, meta=0x0, cmd=(nvme_fabrics_type_property_get attrib=0, ofst=0x8)
     kworker/6:2-1067  [006] ....  1474.572098: nvmet_req_complete: nvme1: qid=0, cmdid=23, res=0x10300, status=0x0
            nvme-2401  [004] ....  1474.572268: nvmet_req_init: nvme1: qid=0, cmdid=8, nsid=4, flags=0x40, meta=0x0, cmd=(nvme_fabrics_type_property_get attrib=1, ofst=0x0)
     kworker/4:2-1235  [004] ....  1474.572287: nvmet_req_complete: nvme1: qid=0, cmdid=8, res=0x200f0003ff, status=0x0
            nvme-2401  [006] ....  1474.572436: nvmet_req_init: nvme1: qid=0, cmdid=24, nsid=0, flags=0x40, meta=0x0, cmd=(nvme_admin_identify cns=1, ctrlid=0)
     kworker/6:2-1067  [006] ....  1474.572462: nvmet_req_complete: nvme1: qid=0, cmdid=24, res=0x0, status=0x0
            nvme-2401  [004] ....  1474.572643: nvmet_req_init: nvme1: qid=0, cmdid=9, nsid=4294967295, flags=0x40, meta=0x0, cmd=(nvme_admin_get_log_page cdw10=05 00 ff 03 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00)
     kworker/4:2-1235  [004] ....  1474.572664: nvmet_req_complete: nvme1: qid=0, cmdid=9, res=0x0, status=0x0
            nvme-2401  [006] ....  1474.573001: nvmet_req_init: nvme1: qid=0, cmdid=25, nsid=4294967295, flags=0x40, meta=0x0, cmd=(nvme_admin_get_log_page cdw10=0c 01 03 08 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00)
     kworker/6:2-1067  [006] ....  1474.573028: nvmet_req_complete: nvme1: qid=0, cmdid=25, res=0x0, status=0x0
            nvme-2401  [004] ....  1474.573158: nvmet_req_init: nvme1: qid=0, cmdid=6, nsid=0, flags=0x40, meta=0x0, cmd=(nvme_admin_set_features cdw10=07 00 00 00 07 00 07 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00)
     kworker/4:2-1235  [004] ....  1474.573179: nvmet_req_complete: nvme1: qid=0, cmdid=6, res=0x20007f007f, status=0x0
    kworker/0:1H-1057  [000] ....  1474.574905: nvmet_req_init: nvme0: qid=0, cmdid=0, nsid=1, flags=0x40, meta=0x0, cmd=(nvme_fabrics_type_connect recfmt=0, qid=1, sqsize=127, cattr=0, kato=0)
     kworker/0:2-2118  [000] ....  1474.575025: nvmet_req_complete: nvme1: qid=1, cmdid=0, res=0x0, status=0x0
    kworker/1:1H-1867  [001] ....  1474.575236: nvmet_req_init: nvme0: qid=0, cmdid=0, nsid=1, flags=0x40, meta=0x0, cmd=(nvme_fabrics_type_connect recfmt=0, qid=2, sqsize=127, cattr=0, kato=0)
     kworker/1:1-63    [001] ....  1474.575358: nvmet_req_complete: nvme1: qid=2, cmdid=0, res=0x0, status=0x0

Please review.
Thanks,

Changes to V5:
  - Provide trace code to the target-side instead of a common code
    shared between host and target to avoid disadvantages something bad
    for the performance like cache miss.  It has been suggested by
    Christoph.
  - Removed the third patch out of this series because that has nothing
    to do with this series.
  - Merged the last two commits into a single commit for the review.

Changes to V4:
  - Add Reviewed-by: tag from Sagi. (Thanks to Sagi)
  - Consider endianness for cqe->status when assigning the value in
    trace
  - Add more descriptions about the variable arguments in events.

Changes to V3:
  - Remove additional argument from the caller level.

Changes to V2:
  - Provide a common code for both host and target. (Chaitanya)
  - Add support for tracing requests in target-side (Chaitanya)
  - Make it simple in trace.h without branch out from nvme core module
    (Christoph)

Changes to V1:
  - fabrics commands should also be decoded, not just showing that it's
    a fabrics command. (Christoph)
  - do not make it within nvme admin commands (Chaitanya)

Minwoo Im (3):
  nvmet: introduce nvmet_req_to_ctrl to get ctrl instance
  nvme: trace: do not EXPORT_SYMBOL for a trace function
  nvmet: introduce target-side trace

 drivers/nvme/host/trace.c    |   1 -
 drivers/nvme/target/Makefile |   3 +
 drivers/nvme/target/core.c   |   8 ++
 drivers/nvme/target/nvmet.h  |   9 ++
 drivers/nvme/target/trace.c  | 179 ++++++++++++++++++++++++++++++++++
 drivers/nvme/target/trace.h  | 184 +++++++++++++++++++++++++++++++++++
 6 files changed, 383 insertions(+), 1 deletion(-)
 create mode 100644 drivers/nvme/target/trace.c
 create mode 100644 drivers/nvme/target/trace.h

-- 
2.21.0

[RFC PATCH V6 1/3] nvmet: introduce nvmet_req_to_ctrl to get ctrl instance

[Minwoo Im]

nvme host driver can get the controller instance from
nvme_req(req)->ctrl.  In case of target driver, it needs to get
controller instance from the struct nvmet_req with sq where the request
has been submitted.

Cc: Keith Busch <kbusch at kernel.org>
Cc: Christoph Hellwig <hch at lst.de>
Cc: Sagi Grimberg <sagi at grimberg.me>
Signed-off-by: Minwoo Im <minwoo.im.dev at gmail.com>
---
 drivers/nvme/target/nvmet.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index c25d88fc9dec..2d569a1dc3f4 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -318,6 +318,15 @@ struct nvmet_req {
 	u64			error_slba;
 };
 
+static inline struct nvmet_ctrl *nvmet_req_to_ctrl(struct nvmet_req *req)
+{
+	struct nvmet_sq *sq = req->sq;
+
+	if (sq)
+		return sq->ctrl;
+	return NULL;
+}
+
 extern struct workqueue_struct *buffered_io_wq;
 
 static inline void nvmet_set_result(struct nvmet_req *req, u32 result)
-- 
2.21.0

[RFC PATCH V6 2/3] nvme: trace: do not EXPORT_SYMBOL for a trace function

[Minwoo Im]

nvme_trace_disk_name() is now already being invoked with the function
prototype in trace.h.  We don't need to export this symbol at all.

The following patches are going to provide target-side trace feature
with the exactly same function with this so that this patch removes the
EXPORT_SYMBOL() for this function.

Cc: Keith Busch <kbusch at kernel.org>
Cc: Christoph Hellwig <hch at lst.de>
Cc: Sagi Grimberg <sagi at grimberg.me>
Signed-off-by: Minwoo Im <minwoo.im.dev at gmail.com>
---
 drivers/nvme/host/trace.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/nvme/host/trace.c b/drivers/nvme/host/trace.c
index 5f24ea7a28eb..14b0d2993cbe 100644
--- a/drivers/nvme/host/trace.c
+++ b/drivers/nvme/host/trace.c
@@ -145,6 +145,5 @@ const char *nvme_trace_disk_name(struct trace_seq *p, char *name)
 
 	return ret;
 }
-EXPORT_SYMBOL_GPL(nvme_trace_disk_name);
 
 EXPORT_TRACEPOINT_SYMBOL_GPL(nvme_sq);
-- 
2.21.0

[RFC PATCH V6 3/3] nvmet: introduce target-side trace

[Minwoo Im]

This patch introduces target-side request tracing.  As Christoph
suggested, the trace would not be in a core or module to avoid
disadvantages like cache miss:
  http://lists.infradead.org/pipermail/linux-nvme/2019-June/024721.html

The target-side trace code is totally based on the Johannes's trace code
from the host side.  It has lots of codes duplicated, but it would be
better than having advantages mentioned above.

It also traces not only fabrics commands, but also nvme normal commands.
Once the codes to be shared gets bigger, then we can make it common as
suggsted.

This also removed the create_sq and create_cq trace parsing functions
because it will be done by the connect fabrics command.

Example:
  echo 1 > /sys/kernel/debug/tracing/event/nvmet/nvmet_req_init/enable
  echo 1 > /sys/kernel/debug/tracing/event/nvmet/nvmet_req_complete/enable
  cat /sys/kernel/debug/tracing/trace

Cc: Keith Busch <kbusch at kernel.org>
Cc: Christoph Hellwig <hch at lst.de>
Cc: Sagi Grimberg <sagi at grimberg.me>
Signed-off-by: Minwoo Im <minwoo.im.dev at gmail.com>
---
 drivers/nvme/target/Makefile |   3 +
 drivers/nvme/target/core.c   |   8 ++
 drivers/nvme/target/trace.c  | 179 ++++++++++++++++++++++++++++++++++
 drivers/nvme/target/trace.h  | 184 +++++++++++++++++++++++++++++++++++
 4 files changed, 374 insertions(+)
 create mode 100644 drivers/nvme/target/trace.c
 create mode 100644 drivers/nvme/target/trace.h

diff --git a/drivers/nvme/target/Makefile b/drivers/nvme/target/Makefile
index 8c3ad0fb6860..2b33836f3d3e 100644
--- a/drivers/nvme/target/Makefile
+++ b/drivers/nvme/target/Makefile
@@ -1,5 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 
+ccflags-y				+= -I$(src)
+
 obj-$(CONFIG_NVME_TARGET)		+= nvmet.o
 obj-$(CONFIG_NVME_TARGET_LOOP)		+= nvme-loop.o
 obj-$(CONFIG_NVME_TARGET_RDMA)		+= nvmet-rdma.o
@@ -14,3 +16,4 @@ nvmet-rdma-y	+= rdma.o
 nvmet-fc-y	+= fc.o
 nvme-fcloop-y	+= fcloop.o
 nvmet-tcp-y	+= tcp.o
+nvmet-$(CONFIG_TRACING)	+= trace.o
diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
index 7734a6acff85..0e7f5849ce38 100644
--- a/drivers/nvme/target/core.c
+++ b/drivers/nvme/target/core.c
@@ -10,6 +10,9 @@
 #include <linux/pci-p2pdma.h>
 #include <linux/scatterlist.h>
 
+#define CREATE_TRACE_POINTS
+#include "trace.h"
+
 #include "nvmet.h"
 
 struct workqueue_struct *buffered_io_wq;
@@ -689,6 +692,9 @@ static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
 
 	if (unlikely(status))
 		nvmet_set_error(req, status);
+
+	trace_nvmet_req_complete(req);
+
 	if (req->ns)
 		nvmet_put_namespace(req->ns);
 	req->ops->queue_response(req);
@@ -848,6 +854,8 @@ bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
 	req->error_loc = NVMET_NO_ERROR_LOC;
 	req->error_slba = 0;
 
+	trace_nvmet_req_init(req, req->cmd);
+
 	/* no support for fused commands yet */
 	if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) {
 		req->error_loc = offsetof(struct nvme_common_command, flags);
diff --git a/drivers/nvme/target/trace.c b/drivers/nvme/target/trace.c
new file mode 100644
index 000000000000..83cbb3702deb
--- /dev/null
+++ b/drivers/nvme/target/trace.c
@@ -0,0 +1,179 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * NVM Express target device driver tracepoints
+ * Copyright (c) 2018 Johannes Thumshirn, SUSE Linux GmbH
+ */
+
+#include <asm/unaligned.h>
+#include "trace.h"
+
+static const char *nvme_trace_admin_identify(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+	u8 cns = cdw10[0];
+	u16 ctrlid = get_unaligned_le16(cdw10 + 2);
+
+	trace_seq_printf(p, "cns=%u, ctrlid=%u", cns, ctrlid);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *nvme_trace_admin_get_features(struct trace_seq *p,
+						 u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+	u8 fid = cdw10[0];
+	u8 sel = cdw10[1] & 0x7;
+	u32 cdw11 = get_unaligned_le32(cdw10 + 4);
+
+	trace_seq_printf(p, "fid=0x%x sel=0x%x cdw11=0x%x", fid, sel, cdw11);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *nvme_trace_read_write(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+	u64 slba = get_unaligned_le64(cdw10);
+	u16 length = get_unaligned_le16(cdw10 + 8);
+	u16 control = get_unaligned_le16(cdw10 + 10);
+	u32 dsmgmt = get_unaligned_le32(cdw10 + 12);
+	u32 reftag = get_unaligned_le32(cdw10 +  16);
+
+	trace_seq_printf(p,
+			 "slba=%llu, len=%u, ctrl=0x%x, dsmgmt=%u, reftag=%u",
+			 slba, length, control, dsmgmt, reftag);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *nvme_trace_dsm(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "nr=%u, attributes=%u",
+			 get_unaligned_le32(cdw10),
+			 get_unaligned_le32(cdw10 + 4));
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+static const char *nvme_trace_common(struct trace_seq *p, u8 *cdw10)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	trace_seq_printf(p, "cdw10=%*ph", 24, cdw10);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
+
+const char *nvme_trace_parse_admin_cmd(struct trace_seq *p,
+				       u8 opcode, u8 *cdw10)
+{
+	switch (opcode) {
+	case nvme_admin_identify:
+		return nvme_trace_admin_identify(p, cdw10);
+	case nvme_admin_get_features:
+		return nvme_trace_admin_get_features(p, cdw10);
+	default:
+		return nvme_trace_common(p, cdw10);
+	}
+}
+
+const char *nvme_trace_parse_nvm_cmd(struct trace_seq *p,
+				     u8 opcode, u8 *cdw10)
+{
+	switch (opcode) {
+	case nvme_cmd_read:
+	case nvme_cmd_write:
+	case nvme_cmd_write_zeroes:
+		return nvme_trace_read_write(p, cdw10);
+	case nvme_cmd_dsm:
+		return nvme_trace_dsm(p, cdw10);
+	default:
+		return nvme_trace_common(p, cdw10);
+	}
+}
+
+static const char *nvme_trace_fabrics_property_set(struct trace_seq *p, u8 *spc)
+{
+       const char *ret = trace_seq_buffer_ptr(p);
+       u8 attrib = spc[0];
+       u32 ofst = get_unaligned_le32(spc + 4);
+       u64 value = get_unaligned_le64(spc + 8);
+
+       trace_seq_printf(p, "attrib=%u, ofst=0x%x, value=0x%llx",
+                               attrib, ofst, value);
+       trace_seq_putc(p, 0);
+
+       return ret;
+}
+
+static const char *nvme_trace_fabrics_connect(struct trace_seq *p, u8 *spc)
+{
+       const char *ret = trace_seq_buffer_ptr(p);
+       u16 recfmt = get_unaligned_le16(spc);
+       u16 qid = get_unaligned_le16(spc + 2);
+       u16 sqsize = get_unaligned_le16(spc + 4);
+       u8 cattr = spc[6];
+       u32 kato = get_unaligned_le32(spc + 8);
+
+       trace_seq_printf(p, "recfmt=%u, qid=%u, sqsize=%u, cattr=%u, kato=%u",
+                               recfmt, qid, sqsize, cattr, kato);
+       trace_seq_putc(p, 0);
+
+       return ret;
+}
+
+static const char *nvme_trace_fabrics_property_get(struct trace_seq *p, u8 *spc)
+{
+       const char *ret = trace_seq_buffer_ptr(p);
+       u8 attrib = spc[0];
+       u32 ofst = get_unaligned_le32(spc + 4);
+
+       trace_seq_printf(p, "attrib=%u, ofst=0x%x", attrib, ofst);
+       trace_seq_putc(p, 0);
+
+       return ret;
+}
+
+static const char *nvme_trace_fabrics_common(struct trace_seq *p, u8 *spc)
+{
+       const char *ret = trace_seq_buffer_ptr(p);
+
+       trace_seq_printf(p, "spcecific=%*ph", 24, spc);
+       trace_seq_putc(p, 0);
+
+       return ret;
+}
+
+const char *nvme_trace_parse_fabrics_cmd(struct trace_seq *p,
+                                        u8 fctype, u8 *spc)
+{
+       switch (fctype) {
+       case nvme_fabrics_type_property_set:
+               return nvme_trace_fabrics_property_set(p, spc);
+       case nvme_fabrics_type_connect:
+               return nvme_trace_fabrics_connect(p, spc);
+       case nvme_fabrics_type_property_get:
+               return nvme_trace_fabrics_property_get(p, spc);
+       default:
+               return nvme_trace_fabrics_common(p, spc);
+       }
+}
+
+const char *nvme_trace_disk_name(struct trace_seq *p, char *name)
+{
+	const char *ret = trace_seq_buffer_ptr(p);
+
+	if (*name)
+		trace_seq_printf(p, "disk=%s, ", name);
+	trace_seq_putc(p, 0);
+
+	return ret;
+}
diff --git a/drivers/nvme/target/trace.h b/drivers/nvme/target/trace.h
new file mode 100644
index 000000000000..1709737aceb3
--- /dev/null
+++ b/drivers/nvme/target/trace.h
@@ -0,0 +1,184 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * NVM Express target device driver tracepoints
+ * Copyright (c) 2018 Johannes Thumshirn, SUSE Linux GmbH
+ *
+ * This is totally based on drivers/nvme/host/trace.h
+ */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM nvmet
+
+#if !defined(_TRACE_NVMET_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_NVMET_H
+
+#include <linux/nvme.h>
+#include <linux/tracepoint.h>
+#include <linux/trace_seq.h>
+
+#include "nvmet.h"
+
+#define nvme_admin_opcode_name(opcode)	{ opcode, #opcode }
+#define show_admin_opcode_name(val)					\
+	__print_symbolic(val,						\
+		nvme_admin_opcode_name(nvme_admin_delete_sq),		\
+		nvme_admin_opcode_name(nvme_admin_create_sq),		\
+		nvme_admin_opcode_name(nvme_admin_get_log_page),	\
+		nvme_admin_opcode_name(nvme_admin_delete_cq),		\
+		nvme_admin_opcode_name(nvme_admin_create_cq),		\
+		nvme_admin_opcode_name(nvme_admin_identify),		\
+		nvme_admin_opcode_name(nvme_admin_abort_cmd),		\
+		nvme_admin_opcode_name(nvme_admin_set_features),	\
+		nvme_admin_opcode_name(nvme_admin_get_features),	\
+		nvme_admin_opcode_name(nvme_admin_async_event),		\
+		nvme_admin_opcode_name(nvme_admin_ns_mgmt),		\
+		nvme_admin_opcode_name(nvme_admin_activate_fw),		\
+		nvme_admin_opcode_name(nvme_admin_download_fw),		\
+		nvme_admin_opcode_name(nvme_admin_ns_attach),		\
+		nvme_admin_opcode_name(nvme_admin_keep_alive),		\
+		nvme_admin_opcode_name(nvme_admin_directive_send),	\
+		nvme_admin_opcode_name(nvme_admin_directive_recv),	\
+		nvme_admin_opcode_name(nvme_admin_dbbuf),		\
+		nvme_admin_opcode_name(nvme_admin_format_nvm),		\
+		nvme_admin_opcode_name(nvme_admin_security_send),	\
+		nvme_admin_opcode_name(nvme_admin_security_recv),	\
+		nvme_admin_opcode_name(nvme_admin_sanitize_nvm))
+
+#define nvme_opcode_name(opcode)	{ opcode, #opcode }
+#define show_nvm_opcode_name(val)				\
+	__print_symbolic(val,					\
+		nvme_opcode_name(nvme_cmd_flush),		\
+		nvme_opcode_name(nvme_cmd_write),		\
+		nvme_opcode_name(nvme_cmd_read),		\
+		nvme_opcode_name(nvme_cmd_write_uncor),		\
+		nvme_opcode_name(nvme_cmd_compare),		\
+		nvme_opcode_name(nvme_cmd_write_zeroes),	\
+		nvme_opcode_name(nvme_cmd_dsm),			\
+		nvme_opcode_name(nvme_cmd_resv_register),	\
+		nvme_opcode_name(nvme_cmd_resv_report),		\
+		nvme_opcode_name(nvme_cmd_resv_acquire),	\
+		nvme_opcode_name(nvme_cmd_resv_release))
+
+#define nvme_fabrics_type_name(type)	{ type, #type }
+#define show_fabrics_type_name(type)					\
+	__print_symbolic(type,						\
+		nvme_fabrics_type_name(nvme_fabrics_type_property_set),	\
+		nvme_fabrics_type_name(nvme_fabrics_type_connect),	\
+		nvme_fabrics_type_name(nvme_fabrics_type_property_get))
+
+/*
+ * If not fabrics command, fctype will be ignored.
+ */
+#define show_opcode_name(qid, opcode, fctype)			\
+	((opcode != nvme_fabrics_command) ?			\
+		(qid ?						\
+			show_nvm_opcode_name(opcode) :		\
+			show_admin_opcode_name(opcode)) :	\
+		show_fabrics_type_name(fctype))
+
+const char *nvme_trace_parse_admin_cmd(struct trace_seq *p, u8 opcode,
+		u8 *cdw10);
+const char *nvme_trace_parse_nvm_cmd(struct trace_seq *p, u8 opcode,
+		u8 *cdw10);
+const char *nvme_trace_parse_fabrics_cmd(struct trace_seq *p, u8 fctype,
+		u8 *spc);
+
+#define parse_nvme_cmd(qid, opcode, fctype, cdw10)			\
+	((opcode != nvme_fabrics_command) ?				\
+		(qid ?							\
+			nvme_trace_parse_nvm_cmd(p, opcode, cdw10) :	\
+			nvme_trace_parse_admin_cmd(p, opcode, cdw10)) :	\
+		nvme_trace_parse_fabrics_cmd(p, fctype, cdw10))
+
+const char *nvme_trace_disk_name(struct trace_seq *p, char *name);
+#define __print_disk_name(name)				\
+	nvme_trace_disk_name(p, name)
+
+#ifndef TRACE_HEADER_MULTI_READ
+static inline void __assign_disk_name(char *name, struct gendisk *disk)
+{
+	if (disk)
+		memcpy(name, disk->disk_name, DISK_NAME_LEN);
+	else
+		memset(name, 0, DISK_NAME_LEN);
+}
+#endif
+
+TRACE_EVENT(nvmet_req_init,
+	TP_PROTO(struct nvmet_req *req, struct nvme_command *cmd),
+	TP_ARGS(req, cmd),
+	TP_STRUCT__entry(
+		__array(char, disk, DISK_NAME_LEN)
+		__field(int, ctrl_id)
+		__field(int, qid)
+		__field(u8, opcode)
+		__field(u8, flags)
+		__field(u16, cid)
+		__field(u32, nsid)
+		__field(u8, fctype)
+		__field(u64, metadata)
+		__array(u8, cdw10, 24)
+	),
+	TP_fast_assign(
+		__entry->ctrl_id = nvmet_req_to_ctrl(req) ?
+					nvmet_req_to_ctrl(req)->cntlid : 0;
+		__entry->qid = req->sq ? req->sq->qid : 0;
+		__entry->opcode = cmd->common.opcode;
+		__entry->flags = cmd->common.flags;
+		__entry->cid = cmd->common.command_id;
+		__entry->nsid = le32_to_cpu(cmd->common.nsid);
+		__entry->fctype = __entry->nsid & 0xff;
+		__entry->metadata = le64_to_cpu(cmd->common.metadata);
+		__assign_disk_name(__entry->disk, req->ns ?
+					req->ns->bdev->bd_disk : NULL);
+		memcpy(__entry->cdw10, &cmd->common.cdw10,
+					sizeof(__entry->cdw10));
+	),
+	TP_printk("nvme%d: %sqid=%d, cmdid=%u, nsid=%u, flags=0x%x, "
+		  "meta=0x%llx, cmd=(%s %s)",
+		__entry->ctrl_id, __print_disk_name(__entry->disk),
+		__entry->qid, __entry->cid, __entry->nsid,
+		__entry->flags, __entry->metadata,
+		show_opcode_name(__entry->qid, __entry->opcode,
+					__entry->fctype),
+		parse_nvme_cmd(__entry->qid, __entry->opcode,
+					__entry->fctype, __entry->cdw10))
+);
+
+TRACE_EVENT(nvmet_req_complete,
+	TP_PROTO(struct nvmet_req *req),
+	TP_ARGS(req),
+	TP_STRUCT__entry(
+		__array(char, disk, DISK_NAME_LEN)
+		__field(int, ctrl_id)
+		__field(int, qid)
+		__field(int, cid)
+		__field(u64, result)
+		__field(u16, status)
+	),
+	TP_fast_assign(
+		__entry->ctrl_id = nvmet_req_to_ctrl(req) ?
+					nvmet_req_to_ctrl(req)->cntlid : 0;
+		__entry->qid = req->cq->qid;
+		__entry->cid = req->cqe->command_id;
+		__entry->result = req->cqe->result.u64;
+		__entry->status = le16_to_cpu(req->cqe->status) >> 1;
+		__assign_disk_name(__entry->disk, req->ns ?
+					req->ns->bdev->bd_disk : NULL);
+	),
+	TP_printk("nvme%d: %sqid=%d, cmdid=%u, res=%#llx, status=%#x",
+		__entry->ctrl_id, __print_disk_name(__entry->disk),
+		__entry->qid, __entry->cid, __entry->result,
+		__entry->status)
+
+);
+
+#endif /* _TRACE_NVMET_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#undef TRACE_INCLUDE_FILE
+#define TRACE_INCLUDE_FILE trace
+
+/* This part must be outside protection */
+#include <trace/define_trace.h>
-- 
2.21.0

[RFC PATCH V6 1/3] nvmet: introduce nvmet_req_to_ctrl to get ctrl instance

[Christoph Hellwig]

On Thu, Jun 06, 2019@03:32:27PM +0900, Minwoo Im wrote:
> nvme host driver can get the controller instance from
> nvme_req(req)->ctrl.  In case of target driver, it needs to get
> controller instance from the struct nvmet_req with sq where the request
> has been submitted.

Note that normally we can just dereference ->sq just fine, as it only
isn't set in the low-level code before accepting the initial connect.

Maybe keep this as a helper in trace.h?

[RFC PATCH V6 2/3] nvme: trace: do not EXPORT_SYMBOL for a trace function

[Christoph Hellwig]

Looks fine,

Reviewed-by: Christoph Hellwig <hch at lst.de>

[RFC PATCH V6 3/3] nvmet: introduce target-side trace

[Christoph Hellwig]

> +#define nvme_admin_opcode_name(opcode)	{ opcode, #opcode }
> +#define show_admin_opcode_name(val)					\

All these bits can probably just move to nvme.h, next to the actual
definitions.

> +		__assign_disk_name(__entry->disk, req->ns ?
> +					req->ns->bdev->bd_disk : NULL);

Tis looks it will crash badly when using the file backend.  I think we
need to put a neutral identifier in, e.g. the uuid or something.

[RFC PATCH V6 1/3] nvmet: introduce nvmet_req_to_ctrl to get ctrl instance

[Minwoo Im]

On 19-06-06 08:48:48, Christoph Hellwig wrote:
> On Thu, Jun 06, 2019@03:32:27PM +0900, Minwoo Im wrote:
> > nvme host driver can get the controller instance from
> > nvme_req(req)->ctrl.  In case of target driver, it needs to get
> > controller instance from the struct nvmet_req with sq where the request
> > has been submitted.
> 
> Note that normally we can just dereference ->sq just fine, as it only
> isn't set in the low-level code before accepting the initial connect.

That's good point.  I just wanted to have safe-code here, but that would
be fine.

> Maybe keep this as a helper in trace.h?

That would be better to put tihs function to nvmet.h once it's needed by
nvmet code later time.

Thanks for your review on this, I'll prepare the V7 series.

[RFC PATCH V6 3/3] nvmet: introduce target-side trace

[Minwoo Im]

On 19-06-06 08:51:53, Christoph Hellwig wrote:
> > +#define nvme_admin_opcode_name(opcode)	{ opcode, #opcode }
> > +#define show_admin_opcode_name(val)					\
> 
> All these bits can probably just move to nvme.h, next to the actual
> definitions.

If it's located in <linux/nvme.h> that would be great for the host-side
trace code.

> > +		__assign_disk_name(__entry->disk, req->ns ?
> > +					req->ns->bdev->bd_disk : NULL);
> 
> Tis looks it will crash badly when using the file backend.  I think we
> need to put a neutral identifier in, e.g. the uuid or something.

Sorry I didn't think about the file-backed request at all.  Thanks for
pointing it out.

Will also prepare V7 series with this updates.

Thanks,

[RFC PATCH V6 2/3] nvme: trace: do not EXPORT_SYMBOL for a trace function

[Chaitanya Kulkarni]

Looks good to me.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni at wdc.com>

On 06/05/2019 11:39 PM, Minwoo Im wrote:
> nvme_trace_disk_name() is now already being invoked with the function
> prototype in trace.h.  We don't need to export this symbol at all.
>
> The following patches are going to provide target-side trace feature
> with the exactly same function with this so that this patch removes the
> EXPORT_SYMBOL() for this function.
>
> Cc: Keith Busch <kbusch at kernel.org>
> Cc: Christoph Hellwig <hch at lst.de>
> Cc: Sagi Grimberg <sagi at grimberg.me>
> Signed-off-by: Minwoo Im <minwoo.im.dev at gmail.com>
> ---
>   drivers/nvme/host/trace.c | 1 -
>   1 file changed, 1 deletion(-)
>
> diff --git a/drivers/nvme/host/trace.c b/drivers/nvme/host/trace.c
> index 5f24ea7a28eb..14b0d2993cbe 100644
> --- a/drivers/nvme/host/trace.c
> +++ b/drivers/nvme/host/trace.c
> @@ -145,6 +145,5 @@ const char *nvme_trace_disk_name(struct trace_seq *p, char *name)
>
>   	return ret;
>   }
> -EXPORT_SYMBOL_GPL(nvme_trace_disk_name);
>
>   EXPORT_TRACEPOINT_SYMBOL_GPL(nvme_sq);
>