From: Artem Bityutskiy Subject: [PATCH 8/8] ext2: introduce own superblock dirty flag Date: Wed, 21 Mar 2012 18:14:35 +0200 Message-ID: <1332346475-1441-9-git-send-email-dedekind1@gmail.com> References: <1332346475-1441-1-git-send-email-dedekind1@gmail.com> Cc: Ext4 Mailing List , Linux FS Maling List , Linux Kernel Maling List To: Jan Kara Return-path: In-Reply-To: <1332346475-1441-1-git-send-email-dedekind1@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org From: Artem Bityutskiy We finally do not need VFS's 's_dirt' flag in ext2 - introduce our own 's_dirty' flag instead. Note: the final goal is to get rid of the 'sync_supers()' kernel thread which wakes up every 5 seconds and even if there is nothing to do. Thus, we are pushing superblock management from VFS down to file-systems. Signed-off-by: Artem Bityutskiy --- fs/ext2/super.c | 16 ++++++++-------- include/linux/ext2_fs_sb.h | 1 + 2 files changed, 9 insertions(+), 8 deletions(-) diff --git a/fs/ext2/super.c b/fs/ext2/super.c index 4eee017..bb12634 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -1162,7 +1162,7 @@ static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es, { struct ext2_sb_info *sbi = EXT2_SB(sb); - sb->s_dirt = 0; + sbi->s_dirty = 0; /* * Make sure we first mark the superblock as clean and then start * writing it out. @@ -1213,7 +1213,7 @@ void ext2_write_super(struct super_block *sb) if (!(sb->s_flags & MS_RDONLY)) ext2_sync_fs(sb, 1); else { - sb->s_dirt = 0; + EXT2_SB(sb)->s_dirty = 0; smp_wmb(); } } @@ -1239,7 +1239,7 @@ static void write_super(struct work_struct *work) kfree(sbwork); smp_rmb(); - if (sb->s_dirt) + if (EXT2_SB(sb)->s_dirty) return; ext2_write_super(sb); @@ -1251,12 +1251,12 @@ void ext2_mark_super_dirty(struct super_block *sb) struct sb_delayed_work *sbwork; unsigned long delay; - /* Make sure we see 's_dirt' changes ASAP */ + /* Make sure we see 's_dirty' changes ASAP */ smp_rmb(); - if (sb->s_dirt == 1) + if (sbi->s_dirty == 1) return; - sb->s_dirt = 1; - /* Make other CPUs see the 's_dirt' change as soon as possible */ + sbi->s_dirty = 1; + /* Make other CPUs see the 's_dirty' change as soon as possible */ smp_wmb(); sbwork = kmalloc(sizeof(struct sb_delayed_work), GFP_NOFS); @@ -1266,7 +1266,7 @@ void ext2_mark_super_dirty(struct super_block *sb) * trouble anyway, and the SB will be written out on unmount or * we may be luckier next time it is marked as dirty. */ - sb->s_dirt = 2; + sbi->s_dirty = 2; return; } diff --git a/include/linux/ext2_fs_sb.h b/include/linux/ext2_fs_sb.h index 75aa40e..5938744 100644 --- a/include/linux/ext2_fs_sb.h +++ b/include/linux/ext2_fs_sb.h @@ -99,6 +99,7 @@ struct ext2_sb_info { u32 s_next_generation; unsigned long s_dir_count; u8 *s_debts; + int s_dirty; /* workqueue for synchronizing the superblock */ struct workqueue_struct *sync_super_wq; struct percpu_counter s_freeblocks_counter; -- 1.7.7.6