pNFS/flexfiles: Record resend attempts on I/O failure

If the attempt to do pNFS fails, then record what action we
take to recover (resend, reset to pnfs or reset to mds).
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

fs/nfs/flexfilelayout/flexfilelayout.c

@@ -1321,7 +1321,6 @@ static int ff_layout_read_done_cb(struct rpc_task *task,
 	int new_idx = hdr->pgio_mirror_idx;
 	int err;
 
-	trace_nfs4_pnfs_read(hdr, task->tk_status);
 	if (task->tk_status < 0)
 		ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
 					    hdr->args.offset, hdr->args.count,
@@ -1331,6 +1330,7 @@ static int ff_layout_read_done_cb(struct rpc_task *task,
 					   hdr->ds_clp, hdr->lseg,
 					   hdr->pgio_mirror_idx);
 
+	trace_nfs4_pnfs_read(hdr, err);
 	clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
 	clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
 	switch (err) {
@@ -1494,7 +1494,6 @@ static int ff_layout_write_done_cb(struct rpc_task *task,
 	loff_t end_offs = 0;
 	int err;
 
-	trace_nfs4_pnfs_write(hdr, task->tk_status);
 	if (task->tk_status < 0)
 		ff_layout_io_track_ds_error(hdr->lseg, hdr->pgio_mirror_idx,
 					    hdr->args.offset, hdr->args.count,
@@ -1504,6 +1503,7 @@ static int ff_layout_write_done_cb(struct rpc_task *task,
 					   hdr->ds_clp, hdr->lseg,
 					   hdr->pgio_mirror_idx);
 
+	trace_nfs4_pnfs_write(hdr, err);
 	clear_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
 	clear_bit(NFS_IOHDR_RESEND_MDS, &hdr->flags);
 	switch (err) {
@@ -1537,7 +1537,6 @@ static int ff_layout_commit_done_cb(struct rpc_task *task,
 {
 	int err;
 
-	trace_nfs4_pnfs_commit_ds(data, task->tk_status);
 	if (task->tk_status < 0)
 		ff_layout_io_track_ds_error(data->lseg, data->ds_commit_index,
 					    data->args.offset, data->args.count,
@@ -1546,6 +1545,7 @@ static int ff_layout_commit_done_cb(struct rpc_task *task,
 	err = ff_layout_async_handle_error(task, NULL, data->ds_clp,
 					   data->lseg, data->ds_commit_index);
 
+	trace_nfs4_pnfs_commit_ds(data, err);
 	switch (err) {
 	case -NFS4ERR_RESET_TO_PNFS:
 		pnfs_generic_prepare_to_resend_writes(data);

fs/nfs/nfs4trace.h

@@ -155,6 +155,9 @@ TRACE_DEFINE_ENUM(NFS4ERR_WRONG_CRED);
 TRACE_DEFINE_ENUM(NFS4ERR_WRONG_TYPE);
 TRACE_DEFINE_ENUM(NFS4ERR_XDEV);
 
+TRACE_DEFINE_ENUM(NFS4ERR_RESET_TO_MDS);
+TRACE_DEFINE_ENUM(NFS4ERR_RESET_TO_PNFS);
+
 #define show_nfsv4_errors(error) \
 	__print_symbolic(error, \
 		{ NFS4_OK, "OK" }, \
@@ -305,7 +308,10 @@ TRACE_DEFINE_ENUM(NFS4ERR_XDEV);
 		{ NFS4ERR_WRONGSEC, "WRONGSEC" }, \
 		{ NFS4ERR_WRONG_CRED, "WRONG_CRED" }, \
 		{ NFS4ERR_WRONG_TYPE, "WRONG_TYPE" }, \
-		{ NFS4ERR_XDEV, "XDEV" })
+		{ NFS4ERR_XDEV, "XDEV" }, \
+		/* ***** Internal to Linux NFS client ***** */ \
+		{ NFS4ERR_RESET_TO_MDS, "RESET_TO_MDS" }, \
+		{ NFS4ERR_RESET_TO_PNFS, "RESET_TO_PNFS" })
 
 #define show_open_flags(flags) \
 	__print_flags(flags, "|", \

fs/nfs/pnfs.h

@@ -79,6 +79,10 @@ enum pnfs_try_status {
 	PNFS_TRY_AGAIN     = 2,
 };
 
+/* error codes for internal use */
+#define NFS4ERR_RESET_TO_MDS   12001
+#define NFS4ERR_RESET_TO_PNFS  12002
+
 #ifdef CONFIG_NFS_V4_1
 
 #define LAYOUT_NFSV4_1_MODULE_PREFIX "nfs-layouttype4"
@@ -91,10 +95,6 @@ enum pnfs_try_status {
 #define NFS4_DEF_DS_RETRANS 5
 #define PNFS_DEVICE_RETRY_TIMEOUT (120*HZ)
 
-/* error codes for internal use */
-#define NFS4ERR_RESET_TO_MDS   12001
-#define NFS4ERR_RESET_TO_PNFS  12002
-
 enum {
 	NFS_LAYOUT_RO_FAILED = 0,	/* get ro layout failed stop trying */
 	NFS_LAYOUT_RW_FAILED,		/* get rw layout failed stop trying */