[PATCH v2 23/25] NFSD: Add an nfsd_cb_probe tracepoint

[Chuck Lever <chuck.lever@oracle.com>]

Record a tracepoint event when the server performs a callback
probe. This event can be enabled as a group with other nfsd_cb
tracepoints.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs4callback.c |    1 +
 fs/nfsd/trace.h        |    1 +
 2 files changed, 2 insertions(+)

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index c2a2a58b3581..ddab969d7865 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -998,6 +998,7 @@ static const struct rpc_call_ops nfsd4_cb_probe_ops = {
  */
 void nfsd4_probe_callback(struct nfs4_client *clp)
 {
+	trace_nfsd_cb_probe(clp);
 	nfsd4_mark_cb_state(clp, NFSD4_CB_UNKNOWN);
 	set_bit(NFSD4_CLIENT_CB_UPDATE, &clp->cl_flags);
 	nfsd4_run_cb(&clp->cl_cb_null);
diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h
index 7f6a2cae0019..da8e7a5a9c61 100644
--- a/fs/nfsd/trace.h
+++ b/fs/nfsd/trace.h
@@ -907,6 +907,7 @@ DEFINE_EVENT(nfsd_cb_class, nfsd_cb_##name,		\
 	TP_ARGS(clp))
 
 DEFINE_NFSD_CB_EVENT(state);
+DEFINE_NFSD_CB_EVENT(probe);
 DEFINE_NFSD_CB_EVENT(lost);
 DEFINE_NFSD_CB_EVENT(shutdown);