From: "J. Bruce Fields" Subject: [PATCH] ext4: turn on i_version updates by default Date: Mon, 14 May 2012 10:06:18 -0400 Message-ID: <20120514140618.GA29902@fieldses.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-ext4@vger.kernel.org, linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org To: Theodore Ts'o Return-path: Content-Disposition: inline Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org knfsd needs i_version updates on, as will userspace nfs servers and probably others. The only effects are that inode->i_version is bumped (under the i_lock) in more places, and that ->dirty_inode(I_DIRTY_DATASYNC) may be called more frequently than once per jiffy on write (see file_update_time). However the latter appears to be mostly a no-op in that case. So, simplify our life and just keep this feature turned on all the time. Signed-off-by: J. Bruce Fields --- fs/ext4/super.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) If people are worried that the performance impact isn't obvious, I'll find the time somehow to test this properly.... diff --git a/fs/ext4/super.c b/fs/ext4/super.c index e1fb1d5..a99f827 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1483,7 +1483,7 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, sbi->s_mount_flags |= EXT4_MF_FS_ABORTED; return 1; case Opt_i_version: - sb->s_flags |= MS_I_VERSION; + /* no-op; this is on by default now */ return 1; case Opt_journal_dev: if (is_remount) { @@ -2979,6 +2979,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) goto out_free_orig; } sb->s_fs_info = sbi; + sb->s_flags |= MS_I_VERSION; sbi->s_mount_opt = 0; sbi->s_resuid = EXT4_DEF_RESUID; sbi->s_resgid = EXT4_DEF_RESGID; -- 1.7.9.5