NFSv4.1: new flag for state renewal check

Data servers not sharing a session with the mount MDS always have an empty
cl_superblocks list.
Replace the cl_superblocks empty list check to see if it is time to shut down
renewd with the NFS_CS_STOP_RENEW bit which is not set by such a data server.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index b9ed2a8..a86698c 100644 (file)
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -1019,14 +1019,19 @@ static void nfs_server_insert_lists(struct nfs_server *server)
        spin_lock(&nfs_client_lock);
        list_add_tail_rcu(&server->client_link, &clp->cl_superblocks);
        list_add_tail(&server->master_link, &nfs_volume_list);
+       clear_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
        spin_unlock(&nfs_client_lock);
 
 }
 
 static void nfs_server_remove_lists(struct nfs_server *server)
 {
+       struct nfs_client *clp = server->nfs_client;
+
        spin_lock(&nfs_client_lock);
        list_del_rcu(&server->client_link);
+       if (clp && list_empty(&clp->cl_superblocks))
+               set_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state);
        list_del(&server->master_link);
        spin_unlock(&nfs_client_lock);
 

diff --git a/fs/nfs/nfs4renewd.c b/fs/nfs/nfs4renewd.c
index 402143d..df8e7f3 100644 (file)
--- a/fs/nfs/nfs4renewd.c
+++ b/fs/nfs/nfs4renewd.c
@@ -64,12 +64,8 @@ nfs4_renew_state(struct work_struct *work)
        ops = clp->cl_mvops->state_renewal_ops;
        dprintk("%s: start\n", __func__);
 
-       rcu_read_lock();
-       if (list_empty(&clp->cl_superblocks)) {
-               rcu_read_unlock();
+       if (test_bit(NFS_CS_STOP_RENEW, &clp->cl_res_state))
                goto out;
-       }
-       rcu_read_unlock();
 
        spin_lock(&clp->cl_lock);
        lease = clp->cl_lease_time;

diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 3e112de..0bac417 100644 (file)
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -30,6 +30,7 @@ struct nfs_client {
 #define NFS_CS_CALLBACK                1               /* - callback started */
 #define NFS_CS_IDMAP           2               /* - idmap started */
 #define NFS_CS_RENEWD          3               /* - renewd started */
+#define NFS_CS_STOP_RENEW      4               /* no more state to renew */
        struct sockaddr_storage cl_addr;        /* server identifier */
        size_t                  cl_addrlen;
        char *                  cl_hostname;    /* hostname of server */