[PATCH] adding per sb inode list to make invalidate_inodes() faster

From: Kirill Korotaev
Date: Thu Sep 09 2004 - 10:31:10 EST


I sent this patch once before for 2.4 kernels, here is the version for 2.6.8.1.

This patch fixes the problem that huge inode cache
can make invalidate_inodes() calls very long. Meanwhile
lock_kernel() and inode_lock are being held and the system
can freeze for seconds.
I detected this problem on kernel with 4gb split. When inode cache
was 2.5Gb (1,000,000 of inodes in cache) it took seconds to umount
or turn quota off.

So this patch introduces per-super block inode list which makes
possible to scan sb's only inodes when doing umount.

Signed-Off-By: Kirill Korotaev <dev@xxxxx>

Kirill

--- ./include/linux/fs.h.invl 2004-08-14 14:55:09.000000000 +0400
+++ ./include/linux/fs.h 2004-09-08 18:47:46.989249792 +0400
@@ -419,6 +419,7 @@ static inline int mapping_writably_mappe
struct inode {
struct hlist_node i_hash;
struct list_head i_list;
+ struct list_head i_sb_list;
struct list_head i_dentry;
unsigned long i_ino;
atomic_t i_count;
@@ -750,6 +751,7 @@ struct super_block {
atomic_t s_active;
void *s_security;

+ struct list_head s_inodes; /* all inodes */
struct list_head s_dirty; /* dirty inodes */
struct list_head s_io; /* parked for writeback */
struct hlist_head s_anon; /* anonymous dentries for (nfs) exporting */
--- ./fs/hugetlbfs/inode.c.invl 2004-08-14 14:56:14.000000000 +0400
+++ ./fs/hugetlbfs/inode.c 2004-09-08 19:17:05.787871760 +0400
@@ -198,6 +198,7 @@ static void hugetlbfs_delete_inode(struc
struct hugetlbfs_sb_info *sbinfo = HUGETLBFS_SB(inode->i_sb);

hlist_del_init(&inode->i_hash);
+ list_del(&inode->i_sb_list);
list_del_init(&inode->i_list);
inode->i_state |= I_FREEING;
inodes_stat.nr_inodes--;
@@ -240,6 +241,7 @@ static void hugetlbfs_forget_inode(struc
inodes_stat.nr_unused--;
hlist_del_init(&inode->i_hash);
out_truncate:
+ list_del(&inode->i_sb_list);
list_del_init(&inode->i_list);
inode->i_state |= I_FREEING;
inodes_stat.nr_inodes--;
--- ./fs/inode.c.invl 2004-09-08 18:35:48.082540224 +0400
+++ ./fs/inode.c 2004-09-08 18:57:45.873205592 +0400
@@ -295,7 +295,7 @@ static void dispose_list(struct list_hea
/*
* Invalidate all inodes for a device.
*/
-static int invalidate_list(struct list_head *head, struct super_block * sb, struct list_head * dispose)
+static int invalidate_list(struct list_head *head, struct list_head * dispose)
{
struct list_head *next;
int busy = 0, count = 0;
@@ -308,12 +308,11 @@ static int invalidate_list(struct list_h
next = next->next;
if (tmp == head)
break;
- inode = list_entry(tmp, struct inode, i_list);
- if (inode->i_sb != sb)
- continue;
+ inode = list_entry(tmp, struct inode, i_sb_list);
invalidate_inode_buffers(inode);
if (!atomic_read(&inode->i_count)) {
hlist_del_init(&inode->i_hash);
+ list_del(&inode->i_sb_list);
list_move(&inode->i_list, dispose);
inode->i_state |= I_FREEING;
count++;
@@ -349,10 +348,7 @@ int invalidate_inodes(struct super_block

down(&iprune_sem);
spin_lock(&inode_lock);
- busy = invalidate_list(&inode_in_use, sb, &throw_away);
- busy |= invalidate_list(&inode_unused, sb, &throw_away);
- busy |= invalidate_list(&sb->s_dirty, sb, &throw_away);
- busy |= invalidate_list(&sb->s_io, sb, &throw_away);
+ busy = invalidate_list(&sb->s_inodes, &throw_away);
spin_unlock(&inode_lock);

dispose_list(&throw_away);
@@ -452,6 +448,7 @@ static void prune_icache(int nr_to_scan)
continue;
}
hlist_del_init(&inode->i_hash);
+ list_del(&inode->i_sb_list);
list_move(&inode->i_list, &freeable);
inode->i_state |= I_FREEING;
nr_pruned++;
@@ -561,6 +558,7 @@ struct inode *new_inode(struct super_blo
if (inode) {
spin_lock(&inode_lock);
inodes_stat.nr_inodes++;
+ list_add(&inode->i_sb_list, &sb->s_inodes);
list_add(&inode->i_list, &inode_in_use);
inode->i_ino = ++last_ino;
inode->i_state = 0;
@@ -609,6 +607,7 @@ static struct inode * get_new_inode(stru
goto set_failed;

inodes_stat.nr_inodes++;
+ list_add(&inode->i_sb_list, &sb->s_inodes);
list_add(&inode->i_list, &inode_in_use);
hlist_add_head(&inode->i_hash, head);
inode->i_state = I_LOCK|I_NEW;
@@ -657,6 +656,7 @@ static struct inode * get_new_inode_fast
if (!old) {
inode->i_ino = ino;
inodes_stat.nr_inodes++;
+ list_add(&inode->i_sb_list, &sb->s_inodes);
list_add(&inode->i_list, &inode_in_use);
hlist_add_head(&inode->i_hash, head);
inode->i_state = I_LOCK|I_NEW;
@@ -993,6 +993,7 @@ void generic_delete_inode(struct inode *
{
struct super_operations *op = inode->i_sb->s_op;

+ list_del(&inode->i_sb_list);
list_del_init(&inode->i_list);
inode->i_state|=I_FREEING;
inodes_stat.nr_inodes--;
@@ -1038,6 +1039,7 @@ static void generic_forget_inode(struct
inodes_stat.nr_unused--;
hlist_del_init(&inode->i_hash);
}
+ list_del(&inode->i_sb_list);
list_del_init(&inode->i_list);
inode->i_state|=I_FREEING;
inodes_stat.nr_inodes--;
@@ -1230,33 +1232,15 @@ int remove_inode_dquot_ref(struct inode
void remove_dquot_ref(struct super_block *sb, int type, struct list_head *tofree_head)
{
struct inode *inode;
- struct list_head *act_head;

if (!sb->dq_op)
return; /* nothing to do */
- spin_lock(&inode_lock); /* This lock is for inodes code */

+ spin_lock(&inode_lock); /* This lock is for inodes code */
/* We hold dqptr_sem so we are safe against the quota code */
- list_for_each(act_head, &inode_in_use) {
- inode = list_entry(act_head, struct inode, i_list);
- if (inode->i_sb == sb && !IS_NOQUOTA(inode))
- remove_inode_dquot_ref(inode, type, tofree_head);
- }
- list_for_each(act_head, &inode_unused) {
- inode = list_entry(act_head, struct inode, i_list);
- if (inode->i_sb == sb && !IS_NOQUOTA(inode))
- remove_inode_dquot_ref(inode, type, tofree_head);
- }
- list_for_each(act_head, &sb->s_dirty) {
- inode = list_entry(act_head, struct inode, i_list);
- if (!IS_NOQUOTA(inode))
- remove_inode_dquot_ref(inode, type, tofree_head);
- }
- list_for_each(act_head, &sb->s_io) {
- inode = list_entry(act_head, struct inode, i_list);
+ list_for_each_entry(inode, &sb->s_inodes, i_sb_list)
if (!IS_NOQUOTA(inode))
remove_inode_dquot_ref(inode, type, tofree_head);
- }
spin_unlock(&inode_lock);
}

--- ./fs/super.c.invl 2004-08-14 14:55:22.000000000 +0400
+++ ./fs/super.c 2004-09-08 18:46:47.227334984 +0400
@@ -65,6 +65,7 @@ static struct super_block *alloc_super(v
}
INIT_LIST_HEAD(&s->s_dirty);
INIT_LIST_HEAD(&s->s_io);
+ INIT_LIST_HEAD(&s->s_inodes);
INIT_LIST_HEAD(&s->s_files);
INIT_LIST_HEAD(&s->s_instances);
INIT_HLIST_HEAD(&s->s_anon);