pNFS/flexfiles: Fix layoutstats handling during read failovers

During a read failover, we may end up changing the value of
the pgio_mirror_idx, so make sure that we record the layout
stats before that update.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

diff --git a/fs/nfs/flexfilelayout/flexfilelayout.c b/fs/nfs/flexfilelayout/flexfilelayout.c
index f9264e1922a28b836367b145c215d9ceb8883843..6673d4ff5a2a846c01e2de3e909e167da30156cb 100644 (file)
--- a/fs/nfs/flexfilelayout/flexfilelayout.c
+++ b/fs/nfs/flexfilelayout/flexfilelayout.c
@@ -1289,6 +1289,7 @@ static void ff_layout_io_track_ds_error(struct pnfs_layout_segment *lseg,
 static int ff_layout_read_done_cb(struct rpc_task *task,
                                struct nfs_pgio_header *hdr)
 {
+       int new_idx = hdr->pgio_mirror_idx;
        int err;
 
        trace_nfs4_pnfs_read(hdr, task->tk_status);
@@ -1307,7 +1308,7 @@ static int ff_layout_read_done_cb(struct rpc_task *task,
        case -NFS4ERR_RESET_TO_PNFS:
                if (ff_layout_choose_best_ds_for_read(hdr->lseg,
                                        hdr->pgio_mirror_idx + 1,
-                                       &hdr->pgio_mirror_idx))
+                                       &new_idx))
                        goto out_layouterror;
                set_bit(NFS_IOHDR_RESEND_PNFS, &hdr->flags);
                return task->tk_status;
@@ -1320,7 +1321,9 @@ static int ff_layout_read_done_cb(struct rpc_task *task,
 
        return 0;
 out_layouterror:
+       ff_layout_read_record_layoutstats_done(task, hdr);
        ff_layout_send_layouterror(hdr->lseg);
+       hdr->pgio_mirror_idx = new_idx;
 out_eagain:
        rpc_restart_call_prepare(task);
        return -EAGAIN;