From 033369d1af1264abc23bea2e174aa47cdd212f6f Mon Sep 17 00:00:00 2001 From: Artem Bityutskiy Date: Fri, 1 Jun 2012 17:18:08 +0300 Subject: [PATCH] reiserfs: get rid of resierfs_sync_super This patch stops reiserfs using the VFS 'write_super()' method along with the s_dirt 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 superblock 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. Signed-off-by: Artem Bityutskiy Signed-off-by: Al Viro --- fs/reiserfs/journal.c | 6 +++-- fs/reiserfs/reiserfs.h | 6 +++++ fs/reiserfs/super.c | 54 +++++++++++++++++++++++++++++++++++------- 3 files changed, 55 insertions(+), 11 deletions(-) diff --git a/fs/reiserfs/journal.c b/fs/reiserfs/journal.c index e5e06dd8562..afcadcc03e8 100644 --- a/fs/reiserfs/journal.c +++ b/fs/reiserfs/journal.c @@ -1923,6 +1923,8 @@ static int do_journal_release(struct reiserfs_transaction_handle *th, * the workqueue job (flush_async_commit) needs this lock */ reiserfs_write_unlock(sb); + + cancel_delayed_work_sync(&REISERFS_SB(sb)->old_work); flush_workqueue(commit_wq); if (!reiserfs_mounted_fs_count) { @@ -3314,7 +3316,7 @@ int journal_mark_dirty(struct reiserfs_transaction_handle *th, journal->j_first = cn; journal->j_last = cn; } - sb->s_dirt = 1; + reiserfs_schedule_old_flush(sb); return 0; } @@ -3952,7 +3954,7 @@ static int do_journal_end(struct reiserfs_transaction_handle *th, ** it tells us if we should continue with the journal_end, or just return */ if (!check_journal_end(th, sb, nblocks, flags)) { - sb->s_dirt = 1; + reiserfs_schedule_old_flush(sb); wake_queued_writers(sb); reiserfs_async_progress_wait(sb); goto out; diff --git a/fs/reiserfs/reiserfs.h b/fs/reiserfs/reiserfs.h index 5c700550bb0..33215f57ea0 100644 --- a/fs/reiserfs/reiserfs.h +++ b/fs/reiserfs/reiserfs.h @@ -480,6 +480,11 @@ struct reiserfs_sb_info { struct dentry *priv_root; /* root of /.reiserfs_priv */ struct dentry *xattr_root; /* root of /.reiserfs_priv/xattrs */ int j_errno; + + int work_queued; /* non-zero delayed work is queued */ + struct delayed_work old_work; /* old transactions flush delayed work */ + spinlock_t old_work_lock; /* protects old_work and work_queued */ + #ifdef CONFIG_QUOTA char *s_qf_names[MAXQUOTAS]; int s_jquota_fmt; @@ -2487,6 +2492,7 @@ void reiserfs_abort(struct super_block *sb, int errno, const char *fmt, ...); int reiserfs_allocate_list_bitmaps(struct super_block *s, struct reiserfs_list_bitmap *, unsigned int); +void reiserfs_schedule_old_flush(struct super_block *s); void add_save_link(struct reiserfs_transaction_handle *th, struct inode *inode, int truncate); int remove_save_link(struct inode *inode, int truncate); diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c index 60cddb7e638..651ce767b55 100644 --- a/fs/reiserfs/super.c +++ b/fs/reiserfs/super.c @@ -72,20 +72,58 @@ static int reiserfs_sync_fs(struct super_block *s, int wait) if (!journal_begin(&th, s, 1)) if (!journal_end_sync(&th, s, 1)) reiserfs_flush_old_commits(s); - s->s_dirt = 0; /* Even if it's not true. - * We'll loop forever in sync_supers otherwise */ reiserfs_write_unlock(s); return 0; } -static void reiserfs_write_super(struct super_block *s) +static void flush_old_commits(struct work_struct *work) { + struct reiserfs_sb_info *sbi; + struct super_block *s; + + sbi = container_of(work, struct reiserfs_sb_info, old_work.work); + s = sbi->s_journal->j_work_sb; + + spin_lock(&sbi->old_work_lock); + sbi->work_queued = 0; + spin_unlock(&sbi->old_work_lock); + reiserfs_sync_fs(s, 1); } +void reiserfs_schedule_old_flush(struct super_block *s) +{ + struct reiserfs_sb_info *sbi = REISERFS_SB(s); + unsigned long delay; + + if (s->s_flags & MS_RDONLY) + return; + + spin_lock(&sbi->old_work_lock); + if (!sbi->work_queued) { + delay = msecs_to_jiffies(dirty_writeback_interval * 10); + queue_delayed_work(system_long_wq, &sbi->old_work, delay); + sbi->work_queued = 1; + } + spin_unlock(&sbi->old_work_lock); +} + +static void cancel_old_flush(struct super_block *s) +{ + struct reiserfs_sb_info *sbi = REISERFS_SB(s); + + cancel_delayed_work_sync(&REISERFS_SB(s)->old_work); + spin_lock(&sbi->old_work_lock); + sbi->work_queued = 0; + spin_unlock(&sbi->old_work_lock); +} + static int reiserfs_freeze(struct super_block *s) { struct reiserfs_transaction_handle th; + + cancel_old_flush(s); + reiserfs_write_lock(s); if (!(s->s_flags & MS_RDONLY)) { int err = journal_begin(&th, s, 1); @@ -99,7 +137,6 @@ static int reiserfs_freeze(struct super_block *s) journal_end_sync(&th, s, 1); } } - s->s_dirt = 0; reiserfs_write_unlock(s); return 0; } @@ -483,9 +520,6 @@ static void reiserfs_put_super(struct super_block *s) reiserfs_write_lock(s); - if (s->s_dirt) - reiserfs_write_super(s); - /* change file system state to current state if it was mounted with read-write permissions */ if (!(s->s_flags & MS_RDONLY)) { if (!journal_begin(&th, s, 10)) { @@ -692,7 +726,6 @@ static const struct super_operations reiserfs_sops = { .dirty_inode = reiserfs_dirty_inode, .evict_inode = reiserfs_evict_inode, .put_super = reiserfs_put_super, - .write_super = reiserfs_write_super, .sync_fs = reiserfs_sync_fs, .freeze_fs = reiserfs_freeze, .unfreeze_fs = reiserfs_unfreeze, @@ -1400,7 +1433,6 @@ static int reiserfs_remount(struct super_block *s, int *mount_flags, char *arg) err = journal_end(&th, s, 10); if (err) goto out_err; - s->s_dirt = 0; if (!(*mount_flags & MS_RDONLY)) { dquot_resume(s, -1); @@ -1741,6 +1773,8 @@ static int reiserfs_fill_super(struct super_block *s, void *data, int silent) /* setup default block allocator options */ reiserfs_init_alloc_options(s); + spin_lock_init(&sbi->old_work_lock); + INIT_DELAYED_WORK(&sbi->old_work, flush_old_commits); mutex_init(&sbi->lock); sbi->lock_depth = -1; @@ -2003,6 +2037,8 @@ error_unlocked: reiserfs_write_unlock(s); } + cancel_delayed_work_sync(&REISERFS_SB(s)->old_work); + reiserfs_free_bitmap_cache(s); if (SB_BUFFER_WITH_SB(s)) brelse(SB_BUFFER_WITH_SB(s));