NFSv4.1: Get rid of the NFS_LAYOUT_DESTROYED state

We already have a mechanism for blocking LAYOUTGET by means of the
plh_block_lgets counter. The only "service" that NFS_LAYOUT_DESTROYED
provides at this point is to block layoutget once the layout segment
list is empty, which basically means that you have to wait until
the pnfs_layout_hdr is destroyed before you can do pNFS on that file
again.

This patch enables the reuse of the pnfs_layout_hdr if the layout
segment list is empty.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2012-09-21 14:48:04 -04:00
parent 579342785f
commit 8006bfba36
3 changed files with 2 additions and 17 deletions

View File

@ -279,8 +279,7 @@ filelayout_reset_to_mds(struct pnfs_layout_segment *lseg)
{
struct nfs4_deviceid_node *node = FILELAYOUT_DEVID_NODE(lseg);
return pnfs_test_layout_destroyed(lseg->pls_layout) ||
filelayout_test_devid_unavailable(node);
return filelayout_test_devid_unavailable(node);
}
/*

View File

@ -331,8 +331,6 @@ pnfs_layout_remove_lseg(struct pnfs_layout_hdr *lo,
list_del_init(&lseg->pls_list);
/* Matched by pnfs_get_layout_hdr in pnfs_layout_insert_lseg */
atomic_dec(&lo->plh_refcount);
if (list_empty(&lo->plh_segs))
set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags);
rpc_wake_up(&NFS_SERVER(inode)->roc_rpcwaitq);
}
@ -463,10 +461,8 @@ pnfs_mark_matching_lsegs_invalid(struct pnfs_layout_hdr *lo,
dprintk("%s:Begin lo %p\n", __func__, lo);
if (list_empty(&lo->plh_segs)) {
set_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags);
if (list_empty(&lo->plh_segs))
return 0;
}
list_for_each_entry_safe(lseg, next, &lo->plh_segs, pls_list)
if (!recall_range ||
should_free_lseg(&lseg->pls_range, recall_range)) {
@ -590,7 +586,6 @@ pnfs_layoutgets_blocked(struct pnfs_layout_hdr *lo, nfs4_stateid *stateid,
(int)(lo->plh_barrier - be32_to_cpu(stateid->seqid)) >= 0)
return true;
return lo->plh_block_lgets ||
test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags) ||
test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags) ||
(list_empty(&lo->plh_segs) &&
(atomic_read(&lo->plh_outstanding) > lget));
@ -912,8 +907,6 @@ pnfs_find_alloc_layout(struct inode *ino,
dprintk("%s Begin ino=%p layout=%p\n", __func__, ino, nfsi->layout);
if (nfsi->layout) {
if (test_bit(NFS_LAYOUT_DESTROYED, &nfsi->layout->plh_flags))
return NULL;
pnfs_get_layout_hdr(nfsi->layout);
return nfsi->layout;
}

View File

@ -62,7 +62,6 @@ enum {
NFS_LAYOUT_RW_FAILED, /* get rw layout failed stop trying */
NFS_LAYOUT_BULK_RECALL, /* bulk recall affecting layout */
NFS_LAYOUT_ROC, /* some lseg had roc bit set */
NFS_LAYOUT_DESTROYED, /* no new use of layout allowed */
NFS_LAYOUT_RETURNED, /* layout has already been returned */
};
@ -278,12 +277,6 @@ pnfs_test_layout_returned(struct pnfs_layout_hdr *lo)
return test_bit(NFS_LAYOUT_RETURNED, &lo->plh_flags);
}
static inline bool
pnfs_test_layout_destroyed(struct pnfs_layout_hdr *lo)
{
return test_bit(NFS_LAYOUT_DESTROYED, &lo->plh_flags);
}
static inline struct pnfs_layout_segment *
pnfs_get_lseg(struct pnfs_layout_segment *lseg)
{