From a26f49926da938f47561f386be56a83dd37a496d Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Mon, 2 Feb 2015 00:37:02 -0500 Subject: ext4: add optimization for the lazytime mount option Add an optimization for the MS_LAZYTIME mount option so that we will opportunistically write out any inodes with the I_DIRTY_TIME flag set in a particular inode table block when we need to update some inode in that inode table block anyway. Also add some temporary code so that we can set the lazytime mount option without needing a modified /sbin/mount program which can set MS_LAZYTIME. We can eventually make this go away once util-linux has added support. Google-Bug-Id: 18297052 Signed-off-by: Theodore Ts'o Signed-off-by: Al Viro --- fs/ext4/inode.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 62 insertions(+), 2 deletions(-) (limited to 'fs/ext4/inode.c') diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 628df5b..9193ea1 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4139,6 +4139,65 @@ static int ext4_inode_blocks_set(handle_t *handle, return 0; } +struct other_inode { + unsigned long orig_ino; + struct ext4_inode *raw_inode; +}; + +static int other_inode_match(struct inode * inode, unsigned long ino, + void *data) +{ + struct other_inode *oi = (struct other_inode *) data; + + if ((inode->i_ino != ino) || + (inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW | + I_DIRTY_SYNC | I_DIRTY_DATASYNC)) || + ((inode->i_state & I_DIRTY_TIME) == 0)) + return 0; + spin_lock(&inode->i_lock); + if (((inode->i_state & (I_FREEING | I_WILL_FREE | I_NEW | + I_DIRTY_SYNC | I_DIRTY_DATASYNC)) == 0) && + (inode->i_state & I_DIRTY_TIME)) { + struct ext4_inode_info *ei = EXT4_I(inode); + + inode->i_state &= ~(I_DIRTY_TIME | I_DIRTY_TIME_EXPIRED); + spin_unlock(&inode->i_lock); + + spin_lock(&ei->i_raw_lock); + EXT4_INODE_SET_XTIME(i_ctime, inode, oi->raw_inode); + EXT4_INODE_SET_XTIME(i_mtime, inode, oi->raw_inode); + EXT4_INODE_SET_XTIME(i_atime, inode, oi->raw_inode); + ext4_inode_csum_set(inode, oi->raw_inode, ei); + spin_unlock(&ei->i_raw_lock); + trace_ext4_other_inode_update_time(inode, oi->orig_ino); + return -1; + } + spin_unlock(&inode->i_lock); + return -1; +} + +/* + * Opportunistically update the other time fields for other inodes in + * the same inode table block. + */ +static void ext4_update_other_inodes_time(struct super_block *sb, + unsigned long orig_ino, char *buf) +{ + struct other_inode oi; + unsigned long ino; + int i, inodes_per_block = EXT4_SB(sb)->s_inodes_per_block; + int inode_size = EXT4_INODE_SIZE(sb); + + oi.orig_ino = orig_ino; + ino = orig_ino & ~(inodes_per_block - 1); + for (i = 0; i < inodes_per_block; i++, ino++, buf += inode_size) { + if (ino == orig_ino) + continue; + oi.raw_inode = (struct ext4_inode *) buf; + (void) find_inode_nowait(sb, ino, other_inode_match, &oi); + } +} + /* * Post the struct inode info into an on-disk inode location in the * buffer-cache. This gobbles the caller's reference to the @@ -4248,10 +4307,11 @@ static int ext4_do_update_inode(handle_t *handle, cpu_to_le16(ei->i_extra_isize); } } - ext4_inode_csum_set(inode, raw_inode, ei); - spin_unlock(&ei->i_raw_lock); + if (inode->i_sb->s_flags & MS_LAZYTIME) + ext4_update_other_inodes_time(inode->i_sb, inode->i_ino, + bh->b_data); BUFFER_TRACE(bh, "call ext4_handle_dirty_metadata"); rc = ext4_handle_dirty_metadata(handle, NULL, bh); -- cgit v1.1