NFSv4.1: Optimise layout return-on-close
Optimise the layout return on close code by ensuring that
1) Add a check for whether we hold a layout before taking any spinlocks
2) Only take the spin lock once
3) Use nfs_state->state to speed up open file checks
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 0a5dda4..4d69076 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -34,6 +34,7 @@
#include "pnfs.h"
#include "iostat.h"
#include "nfs4trace.h"
+#include "delegation.h"
#define NFSDBG_FACILITY NFSDBG_PNFS
#define PNFS_LAYOUTGET_RETRY_TIMEOUT (120*HZ)
@@ -954,30 +955,45 @@
bool pnfs_roc(struct inode *ino)
{
+ struct nfs_inode *nfsi = NFS_I(ino);
+ struct nfs_open_context *ctx;
+ struct nfs4_state *state;
struct pnfs_layout_hdr *lo;
struct pnfs_layout_segment *lseg, *tmp;
LIST_HEAD(tmp_list);
bool found = false;
spin_lock(&ino->i_lock);
- lo = NFS_I(ino)->layout;
+ lo = nfsi->layout;
if (!lo || !test_and_clear_bit(NFS_LAYOUT_ROC, &lo->plh_flags) ||
test_bit(NFS_LAYOUT_BULK_RECALL, &lo->plh_flags))
- goto out_nolayout;
+ goto out_noroc;
+
+ /* Don't return layout if we hold a delegation */
+ if (nfs4_check_delegation(ino, FMODE_READ))
+ goto out_noroc;
+
+ list_for_each_entry(ctx, &nfsi->open_files, list) {
+ state = ctx->state;
+ /* Don't return layout if there is open file state */
+ if (state != NULL && state->state != 0)
+ goto out_noroc;
+ }
+
list_for_each_entry_safe(lseg, tmp, &lo->plh_segs, pls_list)
if (test_bit(NFS_LSEG_ROC, &lseg->pls_flags)) {
mark_lseg_invalid(lseg, &tmp_list);
found = true;
}
if (!found)
- goto out_nolayout;
+ goto out_noroc;
lo->plh_block_lgets++;
pnfs_get_layout_hdr(lo); /* matched in pnfs_roc_release */
spin_unlock(&ino->i_lock);
pnfs_free_lseg_list(&tmp_list);
return true;
-out_nolayout:
+out_noroc:
spin_unlock(&ino->i_lock);
return false;
}
