[PATCH v4 09/18] nfsd: add tracepoint to nfsd_rename

[cel]

From: Jeff Layton <jlayton@xxxxxxxxxx>

Observe the start of RENAME operations for all NFS versions.

Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
---
 fs/nfsd/trace.h | 31 +++++++++++++++++++++++++++++++
 fs/nfsd/vfs.c   |  2 ++
 2 files changed, 33 insertions(+)

diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index e96585546d01..46091d7f2260 100644
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -2522,6 +2522,37 @@ TRACE_EVENT(nfsd_vfs_unlink,
 	)
 );
 
+TRACE_EVENT(nfsd_vfs_rename,
+	TP_PROTO(
+		const struct svc_rqst *rqstp,
+		const struct svc_fh *sfhp,
+		const struct svc_fh *tfhp,
+		const char *source,
+		unsigned int sourcelen,
+		const char *target,
+		unsigned int targetlen
+	),
+	TP_ARGS(rqstp, sfhp, tfhp, source, sourcelen, target, targetlen),
+	TP_STRUCT__entry(
+		NFSD_TRACE_PROC_CALL_FIELDS(rqstp)
+		__field(u32, sfh_hash)
+		__field(u32, tfh_hash)
+		__string_len(source, source, sourcelen)
+		__string_len(target, target, targetlen)
+	),
+	TP_fast_assign(
+		NFSD_TRACE_PROC_CALL_ASSIGNMENTS(rqstp);
+		__entry->sfh_hash = knfsd_fh_hash(&sfhp->fh_handle);
+		__entry->tfh_hash = knfsd_fh_hash(&tfhp->fh_handle);
+		__assign_str(source);
+		__assign_str(target);
+	),
+	TP_printk("xid=0x%08x sfh_hash=0x%08x tfh_hash=0x%08x source=%s target=%s",
+		__entry->xid, __entry->sfh_hash, __entry->tfh_hash,
+		__get_str(source), __get_str(target)
+	)
+);
+
 #endif /* _NFSD_TRACE_H */
 
 #undef TRACE_INCLUDE_PATH
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 820290e5328f..41314b2a8199 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1840,6 +1840,8 @@ nfsd_rename(struct svc_rqst *rqstp, struct svc_fh *ffhp, char *fname, int flen,
 	int		host_err;
 	bool		close_cached = false;
 
+	trace_nfsd_vfs_rename(rqstp, ffhp, tfhp, fname, flen, tname, tlen);
+
 	err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_REMOVE);
 	if (err)
 		goto out;
-- 
2.49.0