From 9e6c5829b07c9ba6668807631914efc557fab059 Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Thu, 12 Jul 2012 17:26:31 +0300 Subject: hfsplus: get rid of write_super This patch makes hfsplus stop using the VFS '->write_super()' method along with the 's_dirt' superblock flag, because they are on their way out. The whole "superblock write-out" VFS infrastructure is served by the 'sync_supers()' kernel thread, which wakes up every 5 (by default) seconds and writes out all dirty superblocks using the '->write_super()' call-back. But the problem with this thread is that it wastes power by waking up the system every 5 seconds, even if there are no diry superblocks, or there are no client file-systems which would need this (e.g., btrfs does not use '->write_super()'). So we want to kill it completely and thus, we need to make file-systems to stop using the '->write_super()' VFS service, and then remove it together with the kernel thread. Tested using fsstress from the LTP project. Signed-off-by: Artem Bityutskiy Signed-off-by: Al Viro --- fs/hfsplus/super.c | 41 ++++++++++++++++++++++++++++++++--------- 1 file changed, 32 insertions(+), 9 deletions(-) (limited to 'fs/hfsplus/super.c') diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c index f4f3d5463061..473332098013 100644 --- a/fs/hfsplus/super.c +++ b/fs/hfsplus/super.c @@ -124,7 +124,7 @@ static int hfsplus_system_write_inode(struct inode *inode) if (fork->total_size != cpu_to_be64(inode->i_size)) { set_bit(HFSPLUS_SB_WRITEBACKUP, &sbi->flags); - inode->i_sb->s_dirt = 1; + hfsplus_mark_mdb_dirty(inode->i_sb); } hfsplus_inode_write_fork(inode, fork); if (tree) @@ -173,8 +173,6 @@ static int hfsplus_sync_fs(struct super_block *sb, int wait) dprint(DBG_SUPER, "hfsplus_sync_fs\n"); - sb->s_dirt = 0; - /* * Explicitly write out the special metadata inodes. * @@ -226,12 +224,34 @@ out: return error; } -static void hfsplus_write_super(struct super_block *sb) +static void delayed_sync_fs(struct work_struct *work) { - if (!(sb->s_flags & MS_RDONLY)) - hfsplus_sync_fs(sb, 1); - else - sb->s_dirt = 0; + struct hfsplus_sb_info *sbi; + + sbi = container_of(work, struct hfsplus_sb_info, sync_work.work); + + spin_lock(&sbi->work_lock); + sbi->work_queued = 0; + spin_unlock(&sbi->work_lock); + + hfsplus_sync_fs(sbi->alloc_file->i_sb, 1); +} + +void hfsplus_mark_mdb_dirty(struct super_block *sb) +{ + struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb); + unsigned long delay; + + if (sb->s_flags & MS_RDONLY) + return; + + spin_lock(&sbi->work_lock); + if (!sbi->work_queued) { + delay = msecs_to_jiffies(dirty_writeback_interval * 10); + queue_delayed_work(system_long_wq, &sbi->sync_work, delay); + sbi->work_queued = 1; + } + spin_unlock(&sbi->work_lock); } static void hfsplus_put_super(struct super_block *sb) @@ -240,6 +260,8 @@ static void hfsplus_put_super(struct super_block *sb) dprint(DBG_SUPER, "hfsplus_put_super\n"); + cancel_delayed_work_sync(&sbi->sync_work); + if (!(sb->s_flags & MS_RDONLY) && sbi->s_vhdr) { struct hfsplus_vh *vhdr = sbi->s_vhdr; @@ -325,7 +347,6 @@ static const struct super_operations hfsplus_sops = { .write_inode = hfsplus_write_inode, .evict_inode = hfsplus_evict_inode, .put_super = hfsplus_put_super, - .write_super = hfsplus_write_super, .sync_fs = hfsplus_sync_fs, .statfs = hfsplus_statfs, .remount_fs = hfsplus_remount, @@ -352,6 +373,8 @@ static int hfsplus_fill_super(struct super_block *sb, void *data, int silent) sb->s_fs_info = sbi; mutex_init(&sbi->alloc_mutex); mutex_init(&sbi->vh_mutex); + spin_lock_init(&sbi->work_lock); + INIT_DELAYED_WORK(&sbi->sync_work, delayed_sync_fs); hfsplus_fill_defaults(sbi); err = -EINVAL; -- cgit v1.2.3-55-g7522