[patch 32/52] fs: icache protect inode state

npiggin
2010-06-24T03:16:59Z

[-- Attachment #1: fs-inode_lock-scale-6b.patch --]
[-- Type: text/plain, Size: 5272 bytes --]

Protect i_hash, i_sb_list etc members with i_lock.

Signed-off-by: Nick Piggin <npiggin@suse.de>
---
fs/hugetlbfs/inode.c | 1 +
fs/inode.c | 29 ++++++++++++++++++++++++++---
2 files changed, 27 insertions(+), 3 deletions(-)

Index: linux-2.6/fs/inode.c
===================================================================
--- linux-2.6.orig/fs/inode.c
+++ linux-2.6/fs/inode.c
@@ -35,7 +35,11 @@
* wb_inode_list_lock protects:
* inode_in_use, inode_unused, b_io, b_more_io, b_dirty, i_list
* inode->i_lock protects:
- * i_state, i_count
+ * i_state
+ * i_count
+ * i_hash
+ * i_list
+ * i_sb_list
*
* Ordering:
* inode_lock
@@ -373,12 +377,14 @@ static void dispose_list(struct list_hea
clear_inode(inode);

spin_lock(&inode_lock);
+ spin_lock(&sb_inode_list_lock);
+ spin_lock(&inode->i_lock);
spin_lock(&inode_hash_lock);
hlist_del_init(&inode->i_hash);
spin_unlock(&inode_hash_lock);
- spin_lock(&sb_inode_list_lock);
list_del_init(&inode->i_sb_list);
spin_unlock(&sb_inode_list_lock);
+ spin_unlock(&inode->i_lock);
spin_unlock(&inode_lock);

wake_up_inode(inode);
@@ -680,7 +686,6 @@ __inode_add_to_lists(struct super_block
struct inode *inode)
{
atomic_inc(&inodes_stat.nr_inodes);
- spin_lock(&sb_inode_list_lock);
list_add(&inode->i_sb_list, &sb->s_inodes);
spin_unlock(&sb_inode_list_lock);
spin_lock(&wb_inode_list_lock);
@@ -710,7 +715,10 @@ void inode_add_to_lists(struct super_blo
struct hlist_head *head = inode_hashtable + hash(sb, inode->i_ino);

spin_lock(&inode_lock);
+ spin_lock(&sb_inode_list_lock);
+ spin_lock(&inode->i_lock);
__inode_add_to_lists(sb, head, inode);
+ spin_unlock(&inode->i_lock);
spin_unlock(&inode_lock);
}
EXPORT_SYMBOL_GPL(inode_add_to_lists);
@@ -742,9 +750,12 @@ struct inode *new_inode(struct super_blo
inode = alloc_inode(sb);
if (inode) {
spin_lock(&inode_lock);
+ spin_lock(&sb_inode_list_lock);
+ spin_lock(&inode->i_lock);
inode->i_ino = ++last_ino;
inode->i_state = 0;
__inode_add_to_lists(sb, NULL, inode);
+ spin_unlock(&inode->i_lock);
spin_unlock(&inode_lock);
}
return inode;
@@ -808,11 +819,14 @@ static struct inode *get_new_inode(struc
/* We released the lock, so.. */
old = find_inode(sb, head, test, data);
if (!old) {
+ spin_lock(&sb_inode_list_lock);
+ spin_lock(&inode->i_lock);
if (set(inode, data))
goto set_failed;

inode->i_state = I_NEW;
__inode_add_to_lists(sb, head, inode);
+ spin_unlock(&inode->i_lock);
spin_unlock(&inode_lock);

/* Return the locked inode with I_NEW set, the
@@ -837,6 +851,7 @@ static struct inode *get_new_inode(struc

set_failed:
spin_unlock(&inode->i_lock);
+ spin_unlock(&sb_inode_list_lock);
spin_unlock(&inode_lock);
destroy_inode(inode);
return NULL;
@@ -859,9 +874,12 @@ static struct inode *get_new_inode_fast(
/* We released the lock, so.. */
old = find_inode_fast(sb, head, ino);
if (!old) {
+ spin_lock(&sb_inode_list_lock);
+ spin_lock(&inode->i_lock);
inode->i_ino = ino;
inode->i_state = I_NEW;
__inode_add_to_lists(sb, head, inode);
+ spin_unlock(&inode->i_lock);
spin_unlock(&inode_lock);

/* Return the locked inode with I_NEW set, the
@@ -1275,10 +1293,13 @@ EXPORT_SYMBOL(insert_inode_locked4);
void __insert_inode_hash(struct inode *inode, unsigned long hashval)
{
struct hlist_head *head = inode_hashtable + hash(inode->i_sb, hashval);
+
spin_lock(&inode_lock);
+ spin_lock(&inode->i_lock);
spin_lock(&inode_hash_lock);
hlist_add_head(&inode->i_hash, head);
spin_unlock(&inode_hash_lock);
+ spin_unlock(&inode->i_lock);
spin_unlock(&inode_lock);
}
EXPORT_SYMBOL(__insert_inode_hash);
@@ -1292,9 +1313,11 @@ EXPORT_SYMBOL(__insert_inode_hash);
void remove_inode_hash(struct inode *inode)
{
spin_lock(&inode_lock);
+ spin_lock(&inode->i_lock);
spin_lock(&inode_hash_lock);
hlist_del_init(&inode->i_hash);
spin_unlock(&inode_hash_lock);
+ spin_unlock(&inode->i_lock);
spin_unlock(&inode_lock);
}
EXPORT_SYMBOL(remove_inode_hash);
@@ -1338,9 +1361,11 @@ void generic_delete_inode(struct inode *
clear_inode(inode);
}
spin_lock(&inode_lock);
+ spin_lock(&inode->i_lock);
spin_lock(&inode_hash_lock);
hlist_del_init(&inode->i_hash);
spin_unlock(&inode_hash_lock);
+ spin_unlock(&inode->i_lock);
spin_unlock(&inode_lock);
wake_up_inode(inode);
BUG_ON(inode->i_state != I_CLEAR);
@@ -1385,10 +1410,10 @@ int generic_detach_inode(struct inode *i
spin_lock(&inode->i_lock);
WARN_ON(inode->i_state & I_NEW);
inode->i_state &= ~I_WILL_FREE;
- atomic_dec(&inodes_stat.nr_unused);
spin_lock(&inode_hash_lock);
hlist_del_init(&inode->i_hash);
spin_unlock(&inode_hash_lock);
+ atomic_dec(&inodes_stat.nr_unused);
}
spin_lock(&wb_inode_list_lock);
list_del_init(&inode->i_list);
Index: linux-2.6/fs/hugetlbfs/inode.c
===================================================================
--- linux-2.6.orig/fs/hugetlbfs/inode.c
+++ linux-2.6/fs/hugetlbfs/inode.c
@@ -382,6 +382,7 @@ static void hugetlbfs_forget_inode(struc
if (generic_detach_inode(inode)) {
truncate_hugepages(inode, 0);
clear_inode(inode);
+ /* XXX: why no wake_up_inode? */
destroy_inode(inode);
}
}