nfsd: add tracepoint to nfsd_link()

Observe the start of NFS LINK operations.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index e347cdaaa732f94c6853108687ef8d4d6b75f0fc..acbf94cfb720f649a13136143fc60d7e85e3dfed 100644 (file)
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -2471,6 +2471,33 @@ TRACE_EVENT(nfsd_vfs_symlink,
        )
 );
 
+TRACE_EVENT(nfsd_vfs_link,
+       TP_PROTO(
+               const struct svc_rqst *rqstp,
+               const struct svc_fh *sfhp,
+               const struct svc_fh *tfhp,
+               const char *name,
+               unsigned int namelen
+       ),
+       TP_ARGS(rqstp, sfhp, tfhp, name, namelen),
+       TP_STRUCT__entry(
+               NFSD_TRACE_PROC_CALL_FIELDS(rqstp)
+               __field(u32, sfh_hash)
+               __field(u32, tfh_hash)
+               __string_len(name, name, namelen)
+       ),
+       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(name);
+       ),
+       TP_printk("xid=0x%08x src_fh=0x%08x tgt_fh=0x%08x name=%s",
+               __entry->xid, __entry->sfh_hash, __entry->tfh_hash,
+               __get_str(name)
+       )
+);
+
 #endif /* _NFSD_TRACE_H */
 
 #undef TRACE_INCLUDE_PATH

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index ecd453b260b6e2349d68f3b41d3c3f9dd7347b32..30702f36db98f6bc8e17fef8d9788efb23f5542b 100644 (file)
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -1721,6 +1721,8 @@ nfsd_link(struct svc_rqst *rqstp, struct svc_fh *ffhp,
        __be32          err;
        int             host_err;
 
+       trace_nfsd_vfs_link(rqstp, ffhp, tfhp, name, len);
+
        err = fh_verify(rqstp, ffhp, S_IFDIR, NFSD_MAY_CREATE);
        if (err)
                goto out;