Re: [PATCH 2/2] tracefs: Don't overlay 'struct inode'

[...]

So I could use destroy_inode() for the removing of the link list, and then
free_inode to free it. Something like:

diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c
index 1028ab6d9a74..ae2cb2221acd 100644
--- a/fs/tracefs/inode.c
+++ b/fs/tracefs/inode.c

@@ -53,15 +53,14 @@ static struct inode *tracefs_alloc_inode(struct super_block *sb)
 	return &ti->vfs_inode;
 }
 
-static void tracefs_free_inode_rcu(struct rcu_head *rcu)
+static void tracefs_free_inode(struct inode *inode)
 {
-	struct tracefs_inode *ti;
+	struct tracefs_inode *ti = get_tracefs(inode);
 
-	ti = container_of(rcu, struct tracefs_inode, rcu);
 	kmem_cache_free(tracefs_inode_cachep, ti);
 }
 
-static void tracefs_free_inode(struct inode *inode)
+static void tracefs_destroy_inode(struct inode *inode)
 {
 	struct tracefs_inode *ti = get_tracefs(inode);
 	unsigned long flags;

@@ -69,8 +68,6 @@ static void tracefs_free_inode(struct inode *inode)
 	spin_lock_irqsave(&tracefs_inode_lock, flags);
 	list_del_rcu(&ti->list);
 	spin_unlock_irqrestore(&tracefs_inode_lock, flags);
-
-	call_rcu(&ti->rcu, tracefs_free_inode_rcu);
 }
 
 static ssize_t default_read_file(struct file *file, char __user *buf,

@@ -437,6 +434,7 @@ static int tracefs_drop_inode(struct inode *inode)
 static const struct super_operations tracefs_super_operations = {
 	.alloc_inode    = tracefs_alloc_inode,
 	.free_inode     = tracefs_free_inode,
+	.destroy_inode  = tracefs_destroy_inode,
 	.drop_inode     = tracefs_drop_inode,
 	.statfs		= simple_statfs,
 	.show_options	= tracefs_show_options,

diff --git a/fs/tracefs/internal.h b/fs/tracefs/internal.h
index f704d8348357..d83c2a25f288 100644
--- a/fs/tracefs/internal.h
+++ b/fs/tracefs/internal.h

@@ -10,10 +10,7 @@ enum {
 };
 
 struct tracefs_inode {
-	union {
-		struct inode            vfs_inode;
-		struct rcu_head		rcu;
-	};
+	struct inode            vfs_inode;
 	/* The below gets initialized with memset_after(ti, 0, vfs_inode) */
 	struct list_head	list;
 	unsigned long           flags;

I'll run this under some more tests and see if it doesn't crash.

I'll apply the first patch of this series too, and then probably use this
one.