nilfs2: stop using periodic write_super callback
This removes nilfs_write_super and commit super block in nilfs
internal thread, instead of periodic write_super callback.
VFS layer calls ->write_super callback periodically. However,
it looks like that calling back is ommited when disk I/O is busy.
And when cleanerd (nilfs GC) is runnig, disk I/O tend to be busy thus
nilfs superblock is not synchronized as nilfs designed.
To avoid it, syncing superblock by nilfs thread instead of pdflush.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 70e8613..ed8ec57 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -67,7 +67,6 @@
"(NILFS)");
MODULE_LICENSE("GPL");
-static void nilfs_write_super(struct super_block *sb);
static int nilfs_remount(struct super_block *sb, int *flags, char *data);
/**
@@ -335,49 +334,6 @@
unlock_kernel();
}
-/**
- * nilfs_write_super - write super block(s) of NILFS
- * @sb: super_block
- *
- * nilfs_write_super() gets a fs-dependent lock, writes super block(s), and
- * clears s_dirt. This function is called in the section protected by
- * lock_super().
- *
- * The s_dirt flag is managed by each filesystem and we protect it by ns_sem
- * of the struct the_nilfs. Lock order must be as follows:
- *
- * 1. lock_super()
- * 2. down_write(&nilfs->ns_sem)
- *
- * Inside NILFS, locking ns_sem is enough to protect s_dirt and the buffer
- * of the super block (nilfs->ns_sbp[]).
- *
- * In most cases, VFS functions call lock_super() before calling these
- * methods. So we must be careful not to bring on deadlocks when using
- * lock_super(); see generic_shutdown_super(), write_super(), and so on.
- *
- * Note that order of lock_kernel() and lock_super() depends on contexts
- * of VFS. We should also note that lock_kernel() can be used in its
- * protective section and only the outermost one has an effect.
- */
-static void nilfs_write_super(struct super_block *sb)
-{
- struct nilfs_sb_info *sbi = NILFS_SB(sb);
- struct the_nilfs *nilfs = sbi->s_nilfs;
-
- down_write(&nilfs->ns_sem);
- if (!(sb->s_flags & MS_RDONLY)) {
- if (!nilfs_discontinued(nilfs) &&
- !nilfs_sb_need_update(nilfs)) {
- up_write(&nilfs->ns_sem);
- return;
- }
- nilfs_commit_super(sbi, nilfs_altsb_need_update(nilfs));
- }
- sb->s_dirt = 0;
- up_write(&nilfs->ns_sem);
-}
-
static int nilfs_sync_fs(struct super_block *sb, int wait)
{
struct nilfs_sb_info *sbi = NILFS_SB(sb);
@@ -558,7 +514,7 @@
/* .drop_inode = nilfs_drop_inode, */
.delete_inode = nilfs_delete_inode,
.put_super = nilfs_put_super,
- .write_super = nilfs_write_super,
+ /* .write_super = nilfs_write_super, */
.sync_fs = nilfs_sync_fs,
/* .write_super_lockfs */
/* .unlockfs */