Patch from Alex Tomas <bzzz@tmi.comex.ru>
here is the patch for ext2 concurrent inode allocation.
fs/ext2/ialloc.c | 151 +++++++++++++++++++++++++++------------------
fs/ext2/super.c | 4 +
include/linux/ext2_fs_sb.h | 1
3 files changed, 97 insertions(+), 59 deletions(-)
diff -puN fs/ext2/ialloc.c~ext2-ialloc-no-lock_super fs/ext2/ialloc.c
--- 25/fs/ext2/ialloc.c~ext2-ialloc-no-lock_super 2003-03-16 14:52:42.000000000 -0800
+++ 25-akpm/fs/ext2/ialloc.c 2003-03-16 14:52:52.000000000 -0800
@@ -64,6 +64,62 @@ error_out:
}
/*
+ * Speculatively reserve an inode in a blockgroup which used to have some
+ * spare ones. Later, when we come to actually claim the inode in the bitmap
+ * it may be that it was taken. In that case the allocator will undo this
+ * reservation and try again.
+ *
+ * The inode allocator does not physically alter the superblock. But we still
+ * set sb->s_dirt, because the superblock was "logically" altered - we need to
+ * go and add up the free inodes counts again and flush out the superblock.
+ */
+static void ext2_reserve_inode(struct super_block *sb, int group, int dir)
+{
+ struct ext2_group_desc * desc;
+ struct buffer_head *bh;
+
+ desc = ext2_get_group_desc(sb, group, &bh);
+ if (!desc) {
+ ext2_error(sb, "ext2_reserve_inode",
+ "can't get descriptor for group %d", group);
+ return;
+ }
+
+ spin_lock(&EXT2_SB(sb)->s_bgi[group].ialloc_lock);
+ desc->bg_free_inodes_count =
+ cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) - 1);
+ if (dir)
+ desc->bg_used_dirs_count =
+ cpu_to_le16(le16_to_cpu(desc->bg_used_dirs_count) + 1);
+ spin_unlock(&EXT2_SB(sb)->s_bgi[group].ialloc_lock);
+ sb->s_dirt = 1;
+ mark_buffer_dirty(bh);
+}
+
+static void ext2_release_inode(struct super_block *sb, int group, int dir)
+{
+ struct ext2_group_desc * desc;
+ struct buffer_head *bh;
+
+ desc = ext2_get_group_desc(sb, group, &bh);
+ if (!desc) {
+ ext2_error(sb, "ext2_release_inode",
+ "can't get descriptor for group %d", group);
+ return;
+ }
+
+ spin_lock(&EXT2_SB(sb)->s_bgi[group].ialloc_lock);
+ desc->bg_free_inodes_count =
+ cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) + 1);
+ if (dir)
+ desc->bg_used_dirs_count =
+ cpu_to_le16(le16_to_cpu(desc->bg_used_dirs_count) - 1);
+ spin_unlock(&EXT2_SB(sb)->s_bgi[group].ialloc_lock);
+ sb->s_dirt = 1;
+ mark_buffer_dirty(bh);
+}
+
+/*
* NOTE! When we get the inode, we're the only people
* that have access to it, and as such there are no
* race conditions we have to worry about. The inode
@@ -85,10 +141,8 @@ void ext2_free_inode (struct inode * ino
int is_directory;
unsigned long ino;
struct buffer_head *bitmap_bh = NULL;
- struct buffer_head *bh2;
unsigned long block_group;
unsigned long bit;
- struct ext2_group_desc * desc;
struct ext2_super_block * es;
ino = inode->i_ino;
@@ -105,7 +159,6 @@ void ext2_free_inode (struct inode * ino
DQUOT_DROP(inode);
}
- lock_super (sb);
es = EXT2_SB(sb)->s_es;
is_directory = S_ISDIR(inode->i_mode);
@@ -126,32 +179,17 @@ void ext2_free_inode (struct inode * ino
goto error_return;
/* Ok, now we can actually update the inode bitmaps.. */
- if (!ext2_clear_bit(bit, bitmap_bh->b_data))
+ if (!ext2_clear_bit_atomic(&EXT2_SB(sb)->s_bgi[block_group].ialloc_lock,
+ bit, (void *) bitmap_bh->b_data))
ext2_error (sb, "ext2_free_inode",
"bit already cleared for inode %lu", ino);
- else {
- desc = ext2_get_group_desc (sb, block_group, &bh2);
- if (desc) {
- desc->bg_free_inodes_count =
- cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) + 1);
- if (is_directory) {
- desc->bg_used_dirs_count =
- cpu_to_le16(le16_to_cpu(desc->bg_used_dirs_count) - 1);
- EXT2_SB(sb)->s_dir_count--;
- }
- }
- mark_buffer_dirty(bh2);
- es->s_free_inodes_count =
- cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) + 1);
- mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
- }
+ else
+ ext2_release_inode(sb, block_group, is_directory);
mark_buffer_dirty(bitmap_bh);
if (sb->s_flags & MS_SYNCHRONOUS)
sync_dirty_buffer(bitmap_bh);
- sb->s_dirt = 1;
error_return:
brelse(bitmap_bh);
- unlock_super (sb);
}
/*
@@ -211,9 +249,8 @@ static void ext2_preread_inode(struct in
*/
static int find_group_dir(struct super_block *sb, struct inode *parent)
{
- struct ext2_super_block * es = EXT2_SB(sb)->s_es;
int ngroups = EXT2_SB(sb)->s_groups_count;
- int avefreei = le32_to_cpu(es->s_free_inodes_count) / ngroups;
+ int avefreei = ext2_count_free_inodes(sb) / ngroups;
struct ext2_group_desc *desc, *best_desc = NULL;
struct buffer_head *bh, *best_bh = NULL;
int group, best_group = -1;
@@ -234,11 +271,9 @@ static int find_group_dir(struct super_b
}
if (!best_desc)
return -1;
- best_desc->bg_free_inodes_count =
- cpu_to_le16(le16_to_cpu(best_desc->bg_free_inodes_count) - 1);
- best_desc->bg_used_dirs_count =
- cpu_to_le16(le16_to_cpu(best_desc->bg_used_dirs_count) + 1);
- mark_buffer_dirty(best_bh);
+
+ ext2_reserve_inode(sb, best_group, 1);
+
return best_group;
}
@@ -277,11 +312,12 @@ static int find_group_orlov(struct super
struct ext2_super_block *es = sbi->s_es;
int ngroups = sbi->s_groups_count;
int inodes_per_group = EXT2_INODES_PER_GROUP(sb);
- int avefreei = le32_to_cpu(es->s_free_inodes_count) / ngroups;
+ int freei = ext2_count_free_inodes(sb);
+ int avefreei = freei / ngroups;
int free_blocks = ext2_count_free_blocks(sb);
int avefreeb = free_blocks / ngroups;
int blocks_per_dir;
- int ndirs = sbi->s_dir_count;
+ int ndirs = ext2_count_dirs(sb);
int max_debt, max_dirs, min_blocks, min_inodes;
int group = -1, i;
struct ext2_group_desc *desc;
@@ -364,12 +400,8 @@ fallback:
return -1;
found:
- desc->bg_free_inodes_count =
- cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) - 1);
- desc->bg_used_dirs_count =
- cpu_to_le16(le16_to_cpu(desc->bg_used_dirs_count) + 1);
- sbi->s_dir_count++;
- mark_buffer_dirty(bh);
+ ext2_reserve_inode(sb, group, 1);
+
return group;
}
@@ -431,9 +463,8 @@ static int find_group_other(struct super
return -1;
found:
- desc->bg_free_inodes_count =
- cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) - 1);
- mark_buffer_dirty(bh);
+ ext2_reserve_inode(sb, group, 0);
+
return group;
}
@@ -456,7 +487,6 @@ struct inode * ext2_new_inode(struct ino
return ERR_PTR(-ENOMEM);
ei = EXT2_I(inode);
- lock_super (sb);
es = EXT2_SB(sb)->s_es;
repeat:
if (S_ISDIR(mode)) {
@@ -480,7 +510,12 @@ repeat:
EXT2_INODES_PER_GROUP(sb));
if (i >= EXT2_INODES_PER_GROUP(sb))
goto bad_count;
- ext2_set_bit(i, bitmap_bh->b_data);
+ if (ext2_set_bit_atomic(&EXT2_SB(sb)->s_bgi[group].ialloc_lock,
+ i, (void *) bitmap_bh->b_data)) {
+ brelse(bitmap_bh);
+ ext2_release_inode(sb, group, S_ISDIR(mode));
+ goto repeat;
+ }
mark_buffer_dirty(bitmap_bh);
if (sb->s_flags & MS_SYNCHRONOUS)
@@ -497,9 +532,7 @@ repeat:
goto fail2;
}
- es->s_free_inodes_count =
- cpu_to_le32(le32_to_cpu(es->s_free_inodes_count) - 1);
-
+ spin_lock(&EXT2_SB(sb)->s_bgi[group].ialloc_lock);
if (S_ISDIR(mode)) {
if (EXT2_SB(sb)->s_bgi[group].debts < 255)
EXT2_SB(sb)->s_bgi[group].debts++;
@@ -507,9 +540,8 @@ repeat:
if (EXT2_SB(sb)->s_bgi[group].debts)
EXT2_SB(sb)->s_bgi[group].debts--;
}
+ spin_unlock(&EXT2_SB(sb)->s_bgi[group].ialloc_lock);
- mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
- sb->s_dirt = 1;
inode->i_uid = current->fsuid;
if (test_opt (sb, GRPID))
inode->i_gid = dir->i_gid;
@@ -549,7 +581,6 @@ repeat:
inode->i_generation = EXT2_SB(sb)->s_next_generation++;
insert_inode_hash(inode);
- unlock_super(sb);
if(DQUOT_ALLOC_INODE(inode)) {
DQUOT_DROP(inode);
goto fail3;
@@ -571,15 +602,8 @@ fail3:
return ERR_PTR(err);
fail2:
- desc = ext2_get_group_desc (sb, group, &bh2);
- desc->bg_free_inodes_count =
- cpu_to_le16(le16_to_cpu(desc->bg_free_inodes_count) + 1);
- if (S_ISDIR(mode))
- desc->bg_used_dirs_count =
- cpu_to_le16(le16_to_cpu(desc->bg_used_dirs_count) - 1);
- mark_buffer_dirty(bh2);
+ ext2_release_inode(sb, group, S_ISDIR(mode));
fail:
- unlock_super(sb);
make_bad_inode(inode);
iput(inode);
return ERR_PTR(err);
@@ -602,16 +626,19 @@ bad_count:
unsigned long ext2_count_free_inodes (struct super_block * sb)
{
+ struct ext2_group_desc *desc;
+ unsigned long desc_count = 0;
+ int i;
+
#ifdef EXT2FS_DEBUG
struct ext2_super_block * es;
- unsigned long desc_count = 0, bitmap_count = 0;
+ unsigned long bitmap_count = 0;
struct buffer_head *bitmap_bh = NULL;
int i;
lock_super (sb);
es = EXT2_SB(sb)->s_es;
for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
- struct ext2_group_desc *desc;
unsigned x;
desc = ext2_get_group_desc (sb, i, NULL);
@@ -634,7 +661,13 @@ unsigned long ext2_count_free_inodes (st
unlock_super(sb);
return desc_count;
#else
- return le32_to_cpu(EXT2_SB(sb)->s_es->s_free_inodes_count);
+ for (i = 0; i < EXT2_SB(sb)->s_groups_count; i++) {
+ desc = ext2_get_group_desc (sb, i, NULL);
+ if (!desc)
+ continue;
+ desc_count += le16_to_cpu(desc->bg_free_inodes_count);
+ }
+ return desc_count;
#endif
}
diff -puN fs/ext2/super.c~ext2-ialloc-no-lock_super fs/ext2/super.c
--- 25/fs/ext2/super.c~ext2-ialloc-no-lock_super 2003-03-16 14:52:42.000000000 -0800
+++ 25-akpm/fs/ext2/super.c 2003-03-16 14:52:42.000000000 -0800
@@ -510,6 +510,7 @@ static int ext2_check_descriptors (struc
/* restore free blocks counter in SB -bzzz */
es->s_free_blocks_count = total_free = ext2_count_free_blocks(sb);
+ es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
/* distribute reserved blocks over groups -bzzz */
for(i = sbi->s_groups_count-1; reserved && total_free && i >= 0; i--) {
@@ -803,6 +804,7 @@ static int ext2_fill_super(struct super_
sbi->s_bgi[i].debts = 0;
sbi->s_bgi[i].reserved = 0;
spin_lock_init(&sbi->s_bgi[i].balloc_lock);
+ spin_lock_init(&sbi->s_bgi[i].ialloc_lock);
}
for (i = 0; i < db_count; i++) {
block = descriptor_loc(sb, logic_sb_block, i);
@@ -869,6 +871,7 @@ static void ext2_commit_super (struct su
static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
{
es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
+ es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
es->s_wtime = cpu_to_le32(get_seconds());
mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
@@ -898,6 +901,7 @@ void ext2_write_super (struct super_bloc
es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
~EXT2_VALID_FS);
es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
+ es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
es->s_mtime = cpu_to_le32(get_seconds());
ext2_sync_super(sb, es);
} else
diff -puN include/linux/ext2_fs_sb.h~ext2-ialloc-no-lock_super include/linux/ext2_fs_sb.h
--- 25/include/linux/ext2_fs_sb.h~ext2-ialloc-no-lock_super 2003-03-16 14:52:42.000000000 -0800
+++ 25-akpm/include/linux/ext2_fs_sb.h 2003-03-16 14:52:42.000000000 -0800
@@ -19,6 +19,7 @@
struct ext2_bg_info {
u8 debts;
spinlock_t balloc_lock;
+ spinlock_t ialloc_lock;
unsigned int reserved;
} ____cacheline_aligned_in_smp;
_