diff mbox series

[3/4] NFSv4: Avoid unnecessary scans of filesystems for expired delegations

Message ID dc1b24cf5a44d2677b94b98e1ba66a70fed9ef49.1741023037.git.trond.myklebust@hammerspace.com (mailing list archive)
State Handled Elsewhere
Headers show
Series Fixes for looping in the NFSv4 manager thread | expand

Commit Message

Trond Myklebust March 3, 2025, 5:35 p.m. UTC 
From: Trond Myklebust <trond.myklebust@hammerspace.com>

The amount of looping through the list of delegations is occasionally
leading to soft lockups.  If the state manager was asked to reap the
expired delegations, it should scan only those filesystems that hold
delegations that need to be reaped.

Fixes: 7f156ef0bf45 ("NFSv4: Clean up nfs_delegation_reap_expired()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 fs/nfs/delegation.c       | 7 +++++++
 include/linux/nfs_fs_sb.h | 1 +
 2 files changed, 8 insertions(+)
diff mbox series

Patch

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index d1f5e497729c..abd952cc47e4 100644
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -1284,6 +1284,7 @@  static void nfs_mark_test_expired_delegation(struct nfs_server *server,
 		return;
 	clear_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
 	set_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags);
+	set_bit(NFS4SERV_DELEGATION_EXPIRED, &server->delegation_flags);
 	set_bit(NFS4CLNT_DELEGATION_EXPIRED, &server->nfs_client->cl_state);
 }
 
@@ -1362,6 +1363,9 @@  static int nfs_server_reap_expired_delegations(struct nfs_server *server,
 	nfs4_stateid stateid;
 	unsigned long gen = ++server->delegation_gen;
 
+	if (!test_and_clear_bit(NFS4SERV_DELEGATION_EXPIRED,
+				&server->delegation_flags))
+		return 0;
 restart:
 	rcu_read_lock();
 	list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
@@ -1391,6 +1395,9 @@  static int nfs_server_reap_expired_delegations(struct nfs_server *server,
 			goto restart;
 		}
 		nfs_inode_mark_test_expired_delegation(server,inode);
+		set_bit(NFS4SERV_DELEGATION_EXPIRED, &server->delegation_flags);
+		set_bit(NFS4CLNT_DELEGATION_EXPIRED,
+			&server->nfs_client->cl_state);
 		iput(inode);
 		return -EAGAIN;
 	}
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 4e9ad6f6e907..7d6f164036fa 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -252,6 +252,7 @@  struct nfs_server {
 
 	unsigned long		delegation_flags;
 #define NFS4SERV_DELEGRETURN		(1)
+#define NFS4SERV_DELEGATION_EXPIRED	(2)
 	unsigned long		delegation_gen;
 	unsigned long		mig_gen;
 	unsigned long		mig_status;