NFSv4: Add tracepoints for debugging state management problems

Set up basic tracepoints for debugging client id creation/destruction
and session creation/destruction.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index 6bd483b..7238c4b 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -20,9 +20,11 @@
 nfsv3-$(CONFIG_NFS_V3_ACL) += nfs3acl.o
 
 obj-$(CONFIG_NFS_V4) += nfsv4.o
+CFLAGS_nfs4trace.o += -I$(src)
 nfsv4-y := nfs4proc.o nfs4xdr.o nfs4state.o nfs4renewd.o nfs4super.o nfs4file.o \
 	  delegation.o idmap.o callback.o callback_xdr.o callback_proc.o \
-	  nfs4namespace.o nfs4getroot.o nfs4client.o dns_resolve.o
+	  nfs4namespace.o nfs4getroot.o nfs4client.o dns_resolve.o \
+	  nfs4trace.o
 nfsv4-$(CONFIG_NFS_USE_LEGACY_DNS) += cache_lib.o
 nfsv4-$(CONFIG_SYSCTL)	+= nfs4sysctl.o
 nfsv4-$(CONFIG_NFS_V4_1)	+= nfs4session.o pnfs.o pnfs_dev.o
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index e53e42b..5f228ed 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -66,6 +66,8 @@
 #include "nfs4session.h"
 #include "fscache.h"
 
+#include "nfs4trace.h"
+
 #define NFSDBG_FACILITY		NFSDBG_PROC
 
 #define NFS4_POLL_RETRY_MIN	(HZ/10)
@@ -4064,6 +4066,7 @@
 	struct nfs_client *clp = data->client;
 	unsigned long timestamp = data->timestamp;
 
+	trace_nfs4_renew_async(clp, task->tk_status);
 	if (task->tk_status < 0) {
 		/* Unless we're shutting down, schedule state recovery! */
 		if (test_bit(NFS_CS_RENEWD, &clp->cl_res_state) == 0)
@@ -4730,6 +4733,7 @@
 		clp->cl_rpcclient->cl_auth->au_ops->au_name,
 		setclientid.sc_name_len, setclientid.sc_name);
 	status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
+	trace_nfs4_setclientid(clp, status);
 	dprintk("NFS reply setclientid: %d\n", status);
 	return status;
 }
@@ -4757,6 +4761,7 @@
 		clp->cl_rpcclient->cl_auth->au_ops->au_name,
 		clp->cl_clientid);
 	status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
+	trace_nfs4_setclientid_confirm(clp, status);
 	dprintk("NFS reply setclientid_confirm: %d\n", status);
 	return status;
 }
@@ -5892,6 +5897,7 @@
 	}
 
 	status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
+	trace_nfs4_bind_conn_to_session(clp, status);
 	if (status == 0) {
 		if (memcmp(res.session->sess_id.data,
 		    clp->cl_session->sess_id.data, NFS4_MAX_SESSIONID_LEN)) {
@@ -5977,6 +5983,7 @@
 	}
 
 	status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
+	trace_nfs4_exchange_id(clp, status);
 	if (status == 0)
 		status = nfs4_check_cl_exchange_flags(res.flags);
 
@@ -6037,6 +6044,7 @@
 	int status;
 
 	status = rpc_call_sync(clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
+	trace_nfs4_destroy_clientid(clp, status);
 	if (status)
 		dprintk("NFS: Got error %d from the server %s on "
 			"DESTROY_CLIENTID.", status, clp->cl_hostname);
@@ -6300,6 +6308,7 @@
 	args.flags = (SESSION4_PERSIST | SESSION4_BACK_CHAN);
 
 	status = rpc_call_sync(session->clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
+	trace_nfs4_create_session(clp, status);
 
 	if (!status) {
 		/* Verify the session's negotiated channel_attrs values */
@@ -6363,6 +6372,7 @@
 		return status;
 
 	status = rpc_call_sync(session->clp->cl_rpcclient, &msg, RPC_TASK_TIMEOUT);
+	trace_nfs4_destroy_session(session->clp, status);
 
 	if (status)
 		dprintk("NFS: Got error %d from the server on DESTROY_SESSION. "
@@ -6412,6 +6422,7 @@
 	if (!nfs41_sequence_done(task, task->tk_msg.rpc_resp))
 		return;
 
+	trace_nfs4_sequence(clp, task->tk_status);
 	if (task->tk_status < 0) {
 		dprintk("%s ERROR %d\n", __func__, task->tk_status);
 		if (atomic_read(&clp->cl_count) == 1)
@@ -6564,6 +6575,7 @@
 	if (!nfs41_sequence_done(task, res))
 		return;
 
+	trace_nfs4_reclaim_complete(clp, task->tk_status);
 	if (nfs41_reclaim_complete_handle_errors(task, clp) == -EAGAIN) {
 		rpc_restart_call_prepare(task);
 		return;
diff --git a/fs/nfs/nfs4trace.c b/fs/nfs/nfs4trace.c
new file mode 100644
index 0000000..3f021836
--- /dev/null
+++ b/fs/nfs/nfs4trace.c
@@ -0,0 +1,10 @@
+/*
+ * Copyright (c) 2013 Trond Myklebust <Trond.Myklebust@netapp.com>
+ */
+#include <linux/nfs_fs.h>
+#include "nfs4_fs.h"
+#include "internal.h"
+
+#define CREATE_TRACE_POINTS
+#include "nfs4trace.h"
+
diff --git a/fs/nfs/nfs4trace.h b/fs/nfs/nfs4trace.h
new file mode 100644
index 0000000..9653feb
--- /dev/null
+++ b/fs/nfs/nfs4trace.h
@@ -0,0 +1,220 @@
+/*
+ * Copyright (c) 2013 Trond Myklebust <Trond.Myklebust@netapp.com>
+ */
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM nfs4
+
+#if !defined(_TRACE_NFS4_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_NFS4_H
+
+#include <linux/tracepoint.h>
+
+#define show_nfsv4_errors(error) \
+	__print_symbolic(error, \
+		{ NFS4_OK, "OK" }, \
+		/* Mapped by nfs4_stat_to_errno() */ \
+		{ -EPERM, "EPERM" }, \
+		{ -ENOENT, "ENOENT" }, \
+		{ -EIO, "EIO" }, \
+		{ -ENXIO, "ENXIO" }, \
+		{ -EACCES, "EACCES" }, \
+		{ -EEXIST, "EEXIST" }, \
+		{ -EXDEV, "EXDEV" }, \
+		{ -ENOTDIR, "ENOTDIR" }, \
+		{ -EISDIR, "EISDIR" }, \
+		{ -EFBIG, "EFBIG" }, \
+		{ -ENOSPC, "ENOSPC" }, \
+		{ -EROFS, "EROFS" }, \
+		{ -EMLINK, "EMLINK" }, \
+		{ -ENAMETOOLONG, "ENAMETOOLONG" }, \
+		{ -ENOTEMPTY, "ENOTEMPTY" }, \
+		{ -EDQUOT, "EDQUOT" }, \
+		{ -ESTALE, "ESTALE" }, \
+		{ -EBADHANDLE, "EBADHANDLE" }, \
+		{ -EBADCOOKIE, "EBADCOOKIE" }, \
+		{ -ENOTSUPP, "ENOTSUPP" }, \
+		{ -ETOOSMALL, "ETOOSMALL" }, \
+		{ -EREMOTEIO, "EREMOTEIO" }, \
+		{ -EBADTYPE, "EBADTYPE" }, \
+		{ -EAGAIN, "EAGAIN" }, \
+		{ -ELOOP, "ELOOP" }, \
+		{ -EOPNOTSUPP, "EOPNOTSUPP" }, \
+		{ -EDEADLK, "EDEADLK" }, \
+		/* RPC errors */ \
+		{ -ENOMEM, "ENOMEM" }, \
+		{ -EKEYEXPIRED, "EKEYEXPIRED" }, \
+		{ -ETIMEDOUT, "ETIMEDOUT" }, \
+		{ -ERESTARTSYS, "ERESTARTSYS" }, \
+		{ -ECONNREFUSED, "ECONNREFUSED" }, \
+		{ -ECONNRESET, "ECONNRESET" }, \
+		{ -ENETUNREACH, "ENETUNREACH" }, \
+		{ -EHOSTUNREACH, "EHOSTUNREACH" }, \
+		{ -EHOSTDOWN, "EHOSTDOWN" }, \
+		{ -EPIPE, "EPIPE" }, \
+		{ -EPFNOSUPPORT, "EPFNOSUPPORT" }, \
+		{ -EPROTONOSUPPORT, "EPROTONOSUPPORT" }, \
+		/* NFSv4 native errors */ \
+		{ -NFS4ERR_ACCESS, "ACCESS" }, \
+		{ -NFS4ERR_ATTRNOTSUPP, "ATTRNOTSUPP" }, \
+		{ -NFS4ERR_ADMIN_REVOKED, "ADMIN_REVOKED" }, \
+		{ -NFS4ERR_BACK_CHAN_BUSY, "BACK_CHAN_BUSY" }, \
+		{ -NFS4ERR_BADCHAR, "BADCHAR" }, \
+		{ -NFS4ERR_BADHANDLE, "BADHANDLE" }, \
+		{ -NFS4ERR_BADIOMODE, "BADIOMODE" }, \
+		{ -NFS4ERR_BADLAYOUT, "BADLAYOUT" }, \
+		{ -NFS4ERR_BADLABEL, "BADLABEL" }, \
+		{ -NFS4ERR_BADNAME, "BADNAME" }, \
+		{ -NFS4ERR_BADOWNER, "BADOWNER" }, \
+		{ -NFS4ERR_BADSESSION, "BADSESSION" }, \
+		{ -NFS4ERR_BADSLOT, "BADSLOT" }, \
+		{ -NFS4ERR_BADTYPE, "BADTYPE" }, \
+		{ -NFS4ERR_BADXDR, "BADXDR" }, \
+		{ -NFS4ERR_BAD_COOKIE, "BAD_COOKIE" }, \
+		{ -NFS4ERR_BAD_HIGH_SLOT, "BAD_HIGH_SLOT" }, \
+		{ -NFS4ERR_BAD_RANGE, "BAD_RANGE" }, \
+		{ -NFS4ERR_BAD_SEQID, "BAD_SEQID" }, \
+		{ -NFS4ERR_BAD_SESSION_DIGEST, "BAD_SESSION_DIGEST" }, \
+		{ -NFS4ERR_BAD_STATEID, "BAD_STATEID" }, \
+		{ -NFS4ERR_CB_PATH_DOWN, "CB_PATH_DOWN" }, \
+		{ -NFS4ERR_CLID_INUSE, "CLID_INUSE" }, \
+		{ -NFS4ERR_CLIENTID_BUSY, "CLIENTID_BUSY" }, \
+		{ -NFS4ERR_COMPLETE_ALREADY, "COMPLETE_ALREADY" }, \
+		{ -NFS4ERR_CONN_NOT_BOUND_TO_SESSION, \
+			"CONN_NOT_BOUND_TO_SESSION" }, \
+		{ -NFS4ERR_DEADLOCK, "DEADLOCK" }, \
+		{ -NFS4ERR_DEADSESSION, "DEAD_SESSION" }, \
+		{ -NFS4ERR_DELAY, "DELAY" }, \
+		{ -NFS4ERR_DELEG_ALREADY_WANTED, \
+			"DELEG_ALREADY_WANTED" }, \
+		{ -NFS4ERR_DELEG_REVOKED, "DELEG_REVOKED" }, \
+		{ -NFS4ERR_DENIED, "DENIED" }, \
+		{ -NFS4ERR_DIRDELEG_UNAVAIL, "DIRDELEG_UNAVAIL" }, \
+		{ -NFS4ERR_DQUOT, "DQUOT" }, \
+		{ -NFS4ERR_ENCR_ALG_UNSUPP, "ENCR_ALG_UNSUPP" }, \
+		{ -NFS4ERR_EXIST, "EXIST" }, \
+		{ -NFS4ERR_EXPIRED, "EXPIRED" }, \
+		{ -NFS4ERR_FBIG, "FBIG" }, \
+		{ -NFS4ERR_FHEXPIRED, "FHEXPIRED" }, \
+		{ -NFS4ERR_FILE_OPEN, "FILE_OPEN" }, \
+		{ -NFS4ERR_GRACE, "GRACE" }, \
+		{ -NFS4ERR_HASH_ALG_UNSUPP, "HASH_ALG_UNSUPP" }, \
+		{ -NFS4ERR_INVAL, "INVAL" }, \
+		{ -NFS4ERR_IO, "IO" }, \
+		{ -NFS4ERR_ISDIR, "ISDIR" }, \
+		{ -NFS4ERR_LAYOUTTRYLATER, "LAYOUTTRYLATER" }, \
+		{ -NFS4ERR_LAYOUTUNAVAILABLE, "LAYOUTUNAVAILABLE" }, \
+		{ -NFS4ERR_LEASE_MOVED, "LEASE_MOVED" }, \
+		{ -NFS4ERR_LOCKED, "LOCKED" }, \
+		{ -NFS4ERR_LOCKS_HELD, "LOCKS_HELD" }, \
+		{ -NFS4ERR_LOCK_RANGE, "LOCK_RANGE" }, \
+		{ -NFS4ERR_MINOR_VERS_MISMATCH, "MINOR_VERS_MISMATCH" }, \
+		{ -NFS4ERR_MLINK, "MLINK" }, \
+		{ -NFS4ERR_MOVED, "MOVED" }, \
+		{ -NFS4ERR_NAMETOOLONG, "NAMETOOLONG" }, \
+		{ -NFS4ERR_NOENT, "NOENT" }, \
+		{ -NFS4ERR_NOFILEHANDLE, "NOFILEHANDLE" }, \
+		{ -NFS4ERR_NOMATCHING_LAYOUT, "NOMATCHING_LAYOUT" }, \
+		{ -NFS4ERR_NOSPC, "NOSPC" }, \
+		{ -NFS4ERR_NOTDIR, "NOTDIR" }, \
+		{ -NFS4ERR_NOTEMPTY, "NOTEMPTY" }, \
+		{ -NFS4ERR_NOTSUPP, "NOTSUPP" }, \
+		{ -NFS4ERR_NOT_ONLY_OP, "NOT_ONLY_OP" }, \
+		{ -NFS4ERR_NOT_SAME, "NOT_SAME" }, \
+		{ -NFS4ERR_NO_GRACE, "NO_GRACE" }, \
+		{ -NFS4ERR_NXIO, "NXIO" }, \
+		{ -NFS4ERR_OLD_STATEID, "OLD_STATEID" }, \
+		{ -NFS4ERR_OPENMODE, "OPENMODE" }, \
+		{ -NFS4ERR_OP_ILLEGAL, "OP_ILLEGAL" }, \
+		{ -NFS4ERR_OP_NOT_IN_SESSION, "OP_NOT_IN_SESSION" }, \
+		{ -NFS4ERR_PERM, "PERM" }, \
+		{ -NFS4ERR_PNFS_IO_HOLE, "PNFS_IO_HOLE" }, \
+		{ -NFS4ERR_PNFS_NO_LAYOUT, "PNFS_NO_LAYOUT" }, \
+		{ -NFS4ERR_RECALLCONFLICT, "RECALLCONFLICT" }, \
+		{ -NFS4ERR_RECLAIM_BAD, "RECLAIM_BAD" }, \
+		{ -NFS4ERR_RECLAIM_CONFLICT, "RECLAIM_CONFLICT" }, \
+		{ -NFS4ERR_REJECT_DELEG, "REJECT_DELEG" }, \
+		{ -NFS4ERR_REP_TOO_BIG, "REP_TOO_BIG" }, \
+		{ -NFS4ERR_REP_TOO_BIG_TO_CACHE, \
+			"REP_TOO_BIG_TO_CACHE" }, \
+		{ -NFS4ERR_REQ_TOO_BIG, "REQ_TOO_BIG" }, \
+		{ -NFS4ERR_RESOURCE, "RESOURCE" }, \
+		{ -NFS4ERR_RESTOREFH, "RESTOREFH" }, \
+		{ -NFS4ERR_RETRY_UNCACHED_REP, "RETRY_UNCACHED_REP" }, \
+		{ -NFS4ERR_RETURNCONFLICT, "RETURNCONFLICT" }, \
+		{ -NFS4ERR_ROFS, "ROFS" }, \
+		{ -NFS4ERR_SAME, "SAME" }, \
+		{ -NFS4ERR_SHARE_DENIED, "SHARE_DENIED" }, \
+		{ -NFS4ERR_SEQUENCE_POS, "SEQUENCE_POS" }, \
+		{ -NFS4ERR_SEQ_FALSE_RETRY, "SEQ_FALSE_RETRY" }, \
+		{ -NFS4ERR_SEQ_MISORDERED, "SEQ_MISORDERED" }, \
+		{ -NFS4ERR_SERVERFAULT, "SERVERFAULT" }, \
+		{ -NFS4ERR_STALE, "STALE" }, \
+		{ -NFS4ERR_STALE_CLIENTID, "STALE_CLIENTID" }, \
+		{ -NFS4ERR_STALE_STATEID, "STALE_STATEID" }, \
+		{ -NFS4ERR_SYMLINK, "SYMLINK" }, \
+		{ -NFS4ERR_TOOSMALL, "TOOSMALL" }, \
+		{ -NFS4ERR_TOO_MANY_OPS, "TOO_MANY_OPS" }, \
+		{ -NFS4ERR_UNKNOWN_LAYOUTTYPE, "UNKNOWN_LAYOUTTYPE" }, \
+		{ -NFS4ERR_UNSAFE_COMPOUND, "UNSAFE_COMPOUND" }, \
+		{ -NFS4ERR_WRONGSEC, "WRONGSEC" }, \
+		{ -NFS4ERR_WRONG_CRED, "WRONG_CRED" }, \
+		{ -NFS4ERR_WRONG_TYPE, "WRONG_TYPE" }, \
+		{ -NFS4ERR_XDEV, "XDEV" })
+
+DECLARE_EVENT_CLASS(nfs4_clientid_event,
+		TP_PROTO(
+			const struct nfs_client *clp,
+			int error
+		),
+
+		TP_ARGS(clp, error),
+
+		TP_STRUCT__entry(
+			__string(dstaddr,
+				rpc_peeraddr2str(clp->cl_rpcclient,
+					RPC_DISPLAY_ADDR))
+			__field(int, error)
+		),
+
+		TP_fast_assign(
+			__entry->error = error;
+			__assign_str(dstaddr,
+				rpc_peeraddr2str(clp->cl_rpcclient,
+						RPC_DISPLAY_ADDR));
+		),
+
+		TP_printk(
+			"error=%d (%s) dstaddr=%s",
+			__entry->error,
+			show_nfsv4_errors(__entry->error),
+			__get_str(dstaddr)
+		)
+);
+#define DEFINE_NFS4_CLIENTID_EVENT(name) \
+	DEFINE_EVENT(nfs4_clientid_event, name,	 \
+			TP_PROTO( \
+				const struct nfs_client *clp, \
+				int error \
+			), \
+			TP_ARGS(clp, error))
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_setclientid);
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_setclientid_confirm);
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_renew);
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_renew_async);
+#ifdef CONFIG_NFS_V4_1
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_exchange_id);
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_create_session);
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_destroy_session);
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_destroy_clientid);
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_bind_conn_to_session);
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_sequence);
+DEFINE_NFS4_CLIENTID_EVENT(nfs4_reclaim_complete);
+#endif /* CONFIG_NFS_V4_1 */
+
+#endif /* _TRACE_NFS4_H */
+
+#undef TRACE_INCLUDE_PATH
+#define TRACE_INCLUDE_PATH .
+#define TRACE_INCLUDE_FILE nfs4trace
+/* This part must be outside protection */
+#include <trace/define_trace.h>