NFS: Clean up nfs_sb_active/nfs_sb_deactive

Instead of causing umount requests to block on server->active_wq while the asynchronous sillyrename deletes are executing, we can use the sb->s_active counter to obtain a reference to the super_block, and then release that reference in nfs_async_unlink_release(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

NFS: Clean up nfs_sb_active/nfs_sb_deactive
Instead of causing umount requests to block on server->active_wq while the asynchronous sillyrename deletes are executing, we can use the sb->s_active counter to obtain a reference to the super_block, and then release that reference in nfs_async_unlink_release(). Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Trond Myklebust
1 parent d5e66348bb
Showing 5 changed files with 13 additions and 22 deletions Side-by-side Diff
fs/nfs/client.c
fs/nfs/internal.h
fs/nfs/super.c
fs/nfs/unlink.c
include/linux/nfs_fs_sb.h
@@ -850,7 +850,6 @@
 	INIT_LIST_HEAD(&server->client_link);
 	INIT_LIST_HEAD(&server->master_link);
  
-	init_waitqueue_head(&server->active_wq);
 	atomic_set(&server->active, 0);
  
 	server->io_stats = nfs_alloc_iostats();
@@ -163,8 +163,8 @@
  
 extern int __init register_nfs_fs(void);
 extern void __exit unregister_nfs_fs(void);
-extern void nfs_sb_active(struct nfs_server *server);
-extern void nfs_sb_deactive(struct nfs_server *server);
+extern void nfs_sb_active(struct super_block *sb);
+extern void nfs_sb_deactive(struct super_block *sb);
  
 /* namespace.c */
 extern char *nfs_path(const char *base,
@@ -209,7 +209,6 @@
 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
 		int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 static void nfs_kill_super(struct super_block *);
-static void nfs_put_super(struct super_block *);
 static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
  
 static struct file_system_type nfs_fs_type = {
@@ -232,7 +231,6 @@
 	.alloc_inode	= nfs_alloc_inode,
 	.destroy_inode	= nfs_destroy_inode,
 	.write_inode	= nfs_write_inode,
-	.put_super	= nfs_put_super,
 	.statfs		= nfs_statfs,
 	.clear_inode	= nfs_clear_inode,
 	.umount_begin	= nfs_umount_begin,
  
  
  
  
@@ -337,26 +335,20 @@
 	unregister_filesystem(&nfs_fs_type);
 }
  
-void nfs_sb_active(struct nfs_server *server)
+void nfs_sb_active(struct super_block *sb)
 {
-	atomic_inc(&server->active);
-}
+	struct nfs_server *server = NFS_SB(sb);
  
-void nfs_sb_deactive(struct nfs_server *server)
-{
-	if (atomic_dec_and_test(&server->active))
-		wake_up(&server->active_wq);
+	if (atomic_inc_return(&server->active) == 1)
+		atomic_inc(&sb->s_active);
 }
  
-static void nfs_put_super(struct super_block *sb)
+void nfs_sb_deactive(struct super_block *sb)
 {
 	struct nfs_server *server = NFS_SB(sb);
-	/*
-	 * Make sure there are no outstanding ops to this server.
-	 * If so, wait for them to finish before allowing the
-	 * unmount to continue.
-	 */
-	wait_event(server->active_wq, atomic_read(&server->active) == 0);
+
+	if (atomic_dec_and_test(&server->active))
+		deactivate_super(sb);
 }
  
 /*
@@ -99,7 +99,7 @@
  
 	nfs_dec_sillycount(data->dir);
 	nfs_free_unlinkdata(data);
-	nfs_sb_deactive(NFS_SB(sb));
+	nfs_sb_deactive(sb);
 }
  
 static const struct rpc_call_ops nfs_unlink_ops = {
@@ -118,6 +118,7 @@
 		.rpc_message = &msg,
 		.callback_ops = &nfs_unlink_ops,
 		.callback_data = data,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 	struct rpc_task *task;
@@ -149,7 +150,7 @@
 		nfs_dec_sillycount(dir);
 		return 0;
 	}
-	nfs_sb_active(NFS_SERVER(dir));
+	nfs_sb_active(dir->i_sb);
 	data->args.fh = NFS_FH(dir);
 	nfs_fattr_init(&data->res.dir_attr);
  
@@ -119,7 +119,6 @@
 	void (*destroy)(struct nfs_server *);
  
 	atomic_t active; /* Keep trace of any activity to this server */
-	wait_queue_head_t active_wq;  /* Wait for any activity to stop  */
  
 	/* mountd-related mount options */
 	struct sockaddr_storage	mountd_address;
...	...	@@ -850,7 +850,6 @@
850	850	INIT_LIST_HEAD(&server->client_link);
851	851	INIT_LIST_HEAD(&server->master_link);
852	852
853		- init_waitqueue_head(&server->active_wq);
854	853	atomic_set(&server->active, 0);
855	854
856	855	server->io_stats = nfs_alloc_iostats();
...	...	@@ -163,8 +163,8 @@
163	163
164	164	extern int __init register_nfs_fs(void);
165	165	extern void __exit unregister_nfs_fs(void);
166		-extern void nfs_sb_active(struct nfs_server *server);
167		-extern void nfs_sb_deactive(struct nfs_server *server);
	166	+extern void nfs_sb_active(struct super_block *sb);
	167	+extern void nfs_sb_deactive(struct super_block *sb);
168	168
169	169	/* namespace.c */
170	170	extern char nfs_path(const char base,
...	...	@@ -209,7 +209,6 @@
209	209	static int nfs_xdev_get_sb(struct file_system_type *fs_type,
210	210	int flags, const char dev_name, void raw_data, struct vfsmount *mnt);
211	211	static void nfs_kill_super(struct super_block *);
212		-static void nfs_put_super(struct super_block *);
213	212	static int nfs_remount(struct super_block sb, int flags, char *raw_data);
214	213
215	214	static struct file_system_type nfs_fs_type = {
...	...	@@ -232,7 +231,6 @@
232	231	.alloc_inode = nfs_alloc_inode,
233	232	.destroy_inode = nfs_destroy_inode,
234	233	.write_inode = nfs_write_inode,
235		- .put_super = nfs_put_super,
236	234	.statfs = nfs_statfs,
237	235	.clear_inode = nfs_clear_inode,
238	236	.umount_begin = nfs_umount_begin,
239	237
240	238
241	239
242	240
...	...	@@ -337,26 +335,20 @@
337	335	unregister_filesystem(&nfs_fs_type);
338	336	}
339	337
340		-void nfs_sb_active(struct nfs_server *server)
	338	+void nfs_sb_active(struct super_block *sb)
341	339	{
342		- atomic_inc(&server->active);
343		-}
	340	+ struct nfs_server *server = NFS_SB(sb);
344	341
345		-void nfs_sb_deactive(struct nfs_server *server)
346		-{
347		- if (atomic_dec_and_test(&server->active))
348		- wake_up(&server->active_wq);
	342	+ if (atomic_inc_return(&server->active) == 1)
	343	+ atomic_inc(&sb->s_active);
349	344	}
350	345
351		-static void nfs_put_super(struct super_block *sb)
	346	+void nfs_sb_deactive(struct super_block *sb)
352	347	{
353	348	struct nfs_server *server = NFS_SB(sb);
354		- /*
355		- * Make sure there are no outstanding ops to this server.
356		- * If so, wait for them to finish before allowing the
357		- * unmount to continue.
358		- */
359		- wait_event(server->active_wq, atomic_read(&server->active) == 0);
	349	+
	350	+ if (atomic_dec_and_test(&server->active))
	351	+ deactivate_super(sb);
360	352	}
361	353
362	354	/*
...	...	@@ -99,7 +99,7 @@
99	99
100	100	nfs_dec_sillycount(data->dir);
101	101	nfs_free_unlinkdata(data);
102		- nfs_sb_deactive(NFS_SB(sb));
	102	+ nfs_sb_deactive(sb);
103	103	}
104	104
105	105	static const struct rpc_call_ops nfs_unlink_ops = {
...	...	@@ -118,6 +118,7 @@
118	118	.rpc_message = &msg,
119	119	.callback_ops = &nfs_unlink_ops,
120	120	.callback_data = data,
	121	+ .workqueue = nfsiod_workqueue,
121	122	.flags = RPC_TASK_ASYNC,
122	123	};
123	124	struct rpc_task *task;
...	...	@@ -149,7 +150,7 @@
149	150	nfs_dec_sillycount(dir);
150	151	return 0;
151	152	}
152		- nfs_sb_active(NFS_SERVER(dir));
	153	+ nfs_sb_active(dir->i_sb);
153	154	data->args.fh = NFS_FH(dir);
154	155	nfs_fattr_init(&data->res.dir_attr);
155	156
...	...	@@ -119,7 +119,6 @@
119	119	void (destroy)(struct nfs_server );
120	120
121	121	atomic_t active; /* Keep trace of any activity to this server */
122		- wait_queue_head_t active_wq; /* Wait for any activity to stop */
123	122
124	123	/* mountd-related mount options */
125	124	struct sockaddr_storage mountd_address;