ext4: skip conversion of uninit extents after direct IO if there isn't any

At the end of direct I/O operation, ext4_ext_direct_IO() always called
ext4_convert_unwritten_extents(), regardless of whether there were any
unwritten extents involved in the I/O or not.

This commit adds a state flag so that ext4_ext_direct_IO() only calls
ext4_convert_unwritten_extents() when necessary.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Mingming 2009-11-10 10:48:04 -05:00 committed by Theodore Ts'o
parent 109f556519
commit 5f5249507e
3 changed files with 21 additions and 6 deletions

View file

@ -322,6 +322,7 @@ static inline __u32 ext4_mask_flags(umode_t mode, __u32 flags)
#define EXT4_STATE_NO_EXPAND 0x00000008 /* No space for expansion */
#define EXT4_STATE_DA_ALLOC_CLOSE 0x00000010 /* Alloc DA blks on close */
#define EXT4_STATE_EXT_MIGRATE 0x00000020 /* Inode is migrating */
#define EXT4_STATE_DIO_UNWRITTEN 0x00000040 /* need convert on dio done*/
/* Used to pass group descriptor data when online resize is done */
struct ext4_new_group_input {

View file

@ -3048,12 +3048,18 @@ ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
ret = ext4_split_unwritten_extents(handle,
inode, path, iblock,
max_blocks, flags);
/* flag the io_end struct that we need convert when IO done */
/*
* Flag the inode(non aio case) or end_io struct (aio case)
* that this IO needs to convertion to written when IO is
* completed
*/
if (io)
io->flag = DIO_AIO_UNWRITTEN;
else
EXT4_I(inode)->i_state |= EXT4_STATE_DIO_UNWRITTEN;
goto out;
}
/* DIO end_io complete, convert the filled extent to written */
/* async DIO end_io complete, convert the filled extent to written */
if (flags == EXT4_GET_BLOCKS_DIO_CONVERT_EXT) {
ret = ext4_convert_unwritten_extents_dio(handle, inode,
path);
@ -3295,10 +3301,16 @@ int ext4_ext_get_blocks(handle_t *handle, struct inode *inode,
* To avoid unecessary convertion for every aio dio rewrite
* to the mid of file, here we flag the IO that is really
* need the convertion.
*
* For non asycn direct IO case, flag the inode state
* that we need to perform convertion when IO is done.
*/
if (io && flags == EXT4_GET_BLOCKS_DIO_CREATE_EXT)
io->flag = DIO_AIO_UNWRITTEN;
if (flags == EXT4_GET_BLOCKS_DIO_CREATE_EXT) {
if (io)
io->flag = DIO_AIO_UNWRITTEN;
else
EXT4_I(inode)->i_state |=
EXT4_STATE_DIO_UNWRITTEN;;
}
}
err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
if (err) {

View file

@ -3772,7 +3772,8 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
if (ret != -EIOCBQUEUED && ret <= 0 && iocb->private) {
ext4_free_io_end(iocb->private);
iocb->private = NULL;
} else if (ret > 0) {
} else if (ret > 0 && (EXT4_I(inode)->i_state &
EXT4_STATE_DIO_UNWRITTEN)) {
int err;
/*
* for non AIO case, since the IO is already
@ -3782,6 +3783,7 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
offset, ret);
if (err < 0)
ret = err;
EXT4_I(inode)->i_state &= ~EXT4_STATE_DIO_UNWRITTEN;
}
return ret;
}