On 10/8/24 10:50 AM, Trond Myklebust wrote:
On Tue, 2024-10-08 at 09:57 -0700, Dai Ngo wrote:
After the delegation is returned to the NFS server remove it
from the server's delegations list to reduce the time it takes
to scan this list.
Piggyback the state manager's run to return marked delegations
for this job.
Network trace captured while running the below script shows the
time taken to service the CB_RECALL increases gradually due to
the overhead of traversing the delegation list in
nfs_delegation_find_inode_server.
The NFS server in this test is a Solaris server which issues
CB_RECALL when receiving the all-zero stateid in the SETATTR.
#!/bin/sh
mount=/mnt/data
for i in $(seq 1 20)
do
echo $i
mkdir $mount/testtarfile$i
time tar -C $mount/testtarfile$i -xf 5000_files.tar
done
Signed-off-by: Dai Ngo <dai.ngo@xxxxxxxxxx>
---
fs/nfs/delegation.c | 11 +++++++++++
1 file changed, 11 insertions(+)
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index 20cb2008f9e4..65b10f7ea232 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -642,6 +642,17 @@ static int
nfs_server_return_marked_delegations(struct nfs_server *server,
if (test_bit(NFS_DELEGATION_INODE_FREEING,
&delegation->flags))
continue;
+ if (test_bit(NFS_DELEGATION_REVOKED, &delegation-
flags)) {
+ inode =
nfs_delegation_grab_inode(delegation);
+ if (inode) {
+ rcu_read_unlock();
+ if
(nfs_detach_delegation(NFS_I(inode), delegation, server))
+ nfs_put_delegation(delegatio
n);
+ iput(inode);
+ cond_resched();
+ goto restart;
+ }
+ }
if (!nfs_delegation_need_return(delegation)) {
if (nfs4_is_valid_delegation(delegation, 0))
prev = delegation;
This is not the right place to garbage collect revoked delegations.
We can do something like the above in nfs_revoke_delegation() and in
nfs_delegation_mark_returned() instead.
The code path of nfs_revoke_delegation is only called when the client
gets SEQ4_STATUS_RECALLABLE_STATE_REVOKED error on SEQUENCE op and
when the client tries to reclaim the open state. So this does not help
for this problem.
I'll move this to nfs_delegation_mark_returned().
Thanks,
-Dai
