[PATCH 1/1] pnfs/filelayout: add tracepoint to getdeviceinfo

[Olga Kornievskaia <olga.kornievskaia@xxxxxxxxx>]

From: Olga Kornievskaia <kolga@xxxxxxxxxx>

While decoding filelayout getdeviceinfo received, print out the
information about the location of data servers (IPs).

Generic getdeviceinfo tracepoints prints the MDS's ip for the
dstaddr. In this patch, separate the MDS's address from the
DS's addresses.

Signed-off-by: Olga Kornievskaia <kolga@xxxxxxxxxx>
---
 fs/nfs/filelayout/filelayoutdev.c |  2 ++
 fs/nfs/nfs4trace.c                |  2 ++
 fs/nfs/nfs4trace.h                | 28 ++++++++++++++++++++++++++++
 3 files changed, 32 insertions(+)

diff --git a/fs/nfs/filelayout/filelayoutdev.c b/fs/nfs/filelayout/filelayoutdev.c
index acf4b88889dc..4fa304fa5bc4 100644
--- a/fs/nfs/filelayout/filelayoutdev.c
+++ b/fs/nfs/filelayout/filelayoutdev.c
@@ -35,6 +35,7 @@
 #include "../internal.h"
 #include "../nfs4session.h"
 #include "filelayout.h"
+#include "../nfs4trace.h"
 
 #define NFSDBG_FACILITY		NFSDBG_PNFS_LD
 
@@ -172,6 +173,7 @@ nfs4_fl_alloc_deviceid_node(struct nfs_server *server, struct pnfs_device *pdev,
 		dsaddr->ds_list[i] = nfs4_pnfs_ds_add(&dsaddrs, gfp_flags);
 		if (!dsaddr->ds_list[i])
 			goto out_err_drain_dsaddrs;
+		trace_fl_getdevinfo(server, &pdev->dev_id, dsaddr->ds_list[i]->ds_remotestr);
 
 		/* If DS was already in cache, free ds addrs */
 		while (!list_empty(&dsaddrs)) {
diff --git a/fs/nfs/nfs4trace.c b/fs/nfs/nfs4trace.c
index d9ac556bebcf..d22c6670f770 100644
--- a/fs/nfs/nfs4trace.c
+++ b/fs/nfs/nfs4trace.c
@@ -28,4 +28,6 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(pnfs_mds_fallback_write_pagelist);
 EXPORT_TRACEPOINT_SYMBOL_GPL(ff_layout_read_error);
 EXPORT_TRACEPOINT_SYMBOL_GPL(ff_layout_write_error);
 EXPORT_TRACEPOINT_SYMBOL_GPL(ff_layout_commit_error);
+
+EXPORT_TRACEPOINT_SYMBOL_GPL(fl_getdevinfo);
 #endif
diff --git a/fs/nfs/nfs4trace.h b/fs/nfs/nfs4trace.h
index d27919d7241d..713d080fd268 100644
--- a/fs/nfs/nfs4trace.h
+++ b/fs/nfs/nfs4trace.h
@@ -1991,6 +1991,34 @@ DECLARE_EVENT_CLASS(nfs4_deviceid_status,
 DEFINE_PNFS_DEVICEID_STATUS(nfs4_getdeviceinfo);
 DEFINE_PNFS_DEVICEID_STATUS(nfs4_find_deviceid);
 
+TRACE_EVENT(fl_getdevinfo,
+		TP_PROTO(
+			const struct nfs_server *server,
+			const struct nfs4_deviceid *deviceid,
+			char *ds_remotestr
+		),
+		TP_ARGS(server, deviceid, ds_remotestr),
+
+		TP_STRUCT__entry(
+			__string(mds_addr, server->nfs_client->cl_hostname)
+			__array(unsigned char, deviceid, NFS4_DEVICEID4_SIZE)
+			__string(ds_ips, ds_remotestr)
+		),
+
+		TP_fast_assign(
+			__assign_str(mds_addr, server->nfs_client->cl_hostname);
+			__assign_str(ds_ips, ds_remotestr);
+			memcpy(__entry->deviceid, deviceid->data,
+			       NFS4_DEVICEID4_SIZE);
+		),
+		TP_printk(
+			"deviceid=%s, mds_addr=%s, ds_ips=%s",
+			__print_hex(__entry->deviceid, NFS4_DEVICEID4_SIZE),
+			__get_str(mds_addr),
+			__get_str(ds_ips)
+		)
+);
+
 DECLARE_EVENT_CLASS(nfs4_flexfiles_io_event,
 		TP_PROTO(
 			const struct nfs_pgio_header *hdr
-- 
2.39.1