[PATCH 03/17] pnfs: force a layout commit when encountering busy segments during recall

[Christoph Hellwig <hch@lst.de>]

Expedite layout recall processing by forcing a layout commit when
we see busy segments.  Without it the layout recall might have to wait
until the VM decided to start writeback for the file, which can introduce
long delays.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/nfs/callback_proc.c | 16 +++++++++++-----
 fs/nfs/pnfs.c          |  3 +++
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index 41db525..bf017b0 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -164,6 +164,7 @@ static u32 initiate_file_draining(struct nfs_client *clp,
 	struct inode *ino;
 	struct pnfs_layout_hdr *lo;
 	u32 rv = NFS4ERR_NOMATCHING_LAYOUT;
+	bool need_commit = false;
 	LIST_HEAD(free_me_list);
 
 	lo = get_layout_by_fh(clp, &args->cbl_fh, &args->cbl_stateid);
@@ -172,16 +173,21 @@ static u32 initiate_file_draining(struct nfs_client *clp,
 
 	ino = lo->plh_inode;
 	spin_lock(&ino->i_lock);
-	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
-	    pnfs_mark_matching_lsegs_invalid(lo, &free_me_list,
-					&args->cbl_range))
+	if (test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags)) {
 		rv = NFS4ERR_DELAY;
-	else
-		rv = NFS4ERR_NOMATCHING_LAYOUT;
+	} else if (pnfs_mark_matching_lsegs_invalid(lo, &free_me_list,
+			&args->cbl_range)) {
+		need_commit = true;
+		rv = NFS4ERR_DELAY;
+	}
+
 	pnfs_set_layout_stateid(lo, &args->cbl_stateid, true);
 	spin_unlock(&ino->i_lock);
 	pnfs_free_lseg_list(&free_me_list);
 	pnfs_put_layout_hdr(lo);
+
+	if (need_commit)
+		pnfs_layoutcommit_inode(ino, false);
 	iput(ino);
 out:
 	return rv;
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 6d01740..c72376c 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -604,6 +604,9 @@ pnfs_layout_free_bulk_destroy_list(struct list_head *layout_list,
 		spin_unlock(&inode->i_lock);
 		pnfs_free_lseg_list(&lseg_list);
 		pnfs_put_layout_hdr(lo);
+
+		if (ret)
+			pnfs_layoutcommit_inode(inode, false);
 		iput(inode);
 	}
 	return ret;
-- 
1.9.1