2009-10-09 01:14:11

by Mingming Cao

[permalink] [raw]
Subject: [PATCH 2/4 v2] avoid perform unwritten convertion for direct IO over non fallocated space

ext4: avoid perform unwritten convertion for direct IO over non fallocated space

When direct IO complete, without this patch, it always check and convert
the range covered by the completed IO to be written. This is unnecessary
if the range doesn't has any preallocated area or holes. This patch add
a state flag to alart direct IO code to only run the convertion when
there is unwritten extents being covered in this IO.

Signed-off-by: Mingming Cao <[email protected]>
---
fs/ext4/ext4.h | 1 +
fs/ext4/extents.c | 22 +++++++++++++++++-----
fs/ext4/inode.c | 4 +++-
3 files changed, 21 insertions(+), 6 deletions(-)

Index: linux-2.6.31-rc4/fs/ext4/ext4.h
===================================================================
--- linux-2.6.31-rc4.orig/fs/ext4/ext4.h
+++ linux-2.6.31-rc4/fs/ext4/ext4.h
@@ -299,6 +299,7 @@ static inline __u32 ext4_mask_flags(umod
#define EXT4_STATE_XATTR 0x00000004 /* has in-inode xattrs */
#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_DIO_UNWRITTEN 0x00000020 /* need convert on dio done*/

/* Used to pass group descriptor data when online resize is done */
struct ext4_new_group_input {
Index: linux-2.6.31-rc4/fs/ext4/extents.c
===================================================================
--- linux-2.6.31-rc4.orig/fs/ext4/extents.c
+++ linux-2.6.31-rc4/fs/ext4/extents.c
@@ -3029,12 +3029,18 @@ ext4_ext_handle_uninitialized_extents(ha
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);
@@ -3276,10 +3282,16 @@ int ext4_ext_get_blocks(handle_t *handle
* 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) {
Index: linux-2.6.31-rc4/fs/ext4/inode.c
===================================================================
--- linux-2.6.31-rc4.orig/fs/ext4/inode.c
+++ linux-2.6.31-rc4/fs/ext4/inode.c
@@ -3693,7 +3693,8 @@ static ssize_t ext4_ext_direct_IO(int rw
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
@@ -3703,6 +3704,7 @@ static ssize_t ext4_ext_direct_IO(int rw
offset, ret);
if (err < 0)
ret = err;
+ EXT4_I(inode)->i_state &= ~EXT4_STATE_DIO_UNWRITTEN;
}
return ret;
}




2009-10-20 15:03:57

by Curt Wohlgemuth

[permalink] [raw]
Subject: Re: [PATCH 2/4 v2] avoid perform unwritten convertion for direct IO over non fallocated space

Hi Mingming:

On Thu, Oct 8, 2009 at 6:13 PM, Mingming <[email protected]> wrote:
> ext4: avoid perform unwritten convertion for direct IO over non fallocated space
>
> When direct IO complete, without this patch, it always check and convert
> the range covered by the completed IO to be written. This is unnecessary
> if the range doesn't has any preallocated area or holes. This patch add
> a state flag to alart direct IO code to only run the convertion when
> there is unwritten extents being covered in this IO.
>
> Signed-off-by: Mingming Cao <[email protected]>
> ---
> ?fs/ext4/ext4.h ? ?| ? ?1 +
> ?fs/ext4/extents.c | ? 22 +++++++++++++++++-----
> ?fs/ext4/inode.c ? | ? ?4 +++-
> ?3 files changed, 21 insertions(+), 6 deletions(-)
>
> Index: linux-2.6.31-rc4/fs/ext4/ext4.h
> ===================================================================
> --- linux-2.6.31-rc4.orig/fs/ext4/ext4.h
> +++ linux-2.6.31-rc4/fs/ext4/ext4.h
> @@ -299,6 +299,7 @@ static inline __u32 ext4_mask_flags(umod
> ?#define EXT4_STATE_XATTR ? ? ? ? ? ? ? 0x00000004 /* has in-inode xattrs */
> ?#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_DIO_UNWRITTEN ? ? ? 0x00000020 /* need convert on dio done*/

You'll need to change this value, since EXT4_STATE_EXT_MIGRATE has
already been assigned 0x20.

Thanks,
Curt


>
> ?/* Used to pass group descriptor data when online resize is done */
> ?struct ext4_new_group_input {
> Index: linux-2.6.31-rc4/fs/ext4/extents.c
> ===================================================================
> --- linux-2.6.31-rc4.orig/fs/ext4/extents.c
> +++ linux-2.6.31-rc4/fs/ext4/extents.c
> @@ -3029,12 +3029,18 @@ ext4_ext_handle_uninitialized_extents(ha
> ? ? ? ? ? ? ? ?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);
> @@ -3276,10 +3282,16 @@ int ext4_ext_get_blocks(handle_t *handle
> ? ? ? ? ? ? ? ? * 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) {
> Index: linux-2.6.31-rc4/fs/ext4/inode.c
> ===================================================================
> --- linux-2.6.31-rc4.orig/fs/ext4/inode.c
> +++ linux-2.6.31-rc4/fs/ext4/inode.c
> @@ -3693,7 +3693,8 @@ static ssize_t ext4_ext_direct_IO(int rw
> ? ? ? ? ? ? ? ?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
> @@ -3703,6 +3704,7 @@ static ssize_t ext4_ext_direct_IO(int rw
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?offset, ret);
> ? ? ? ? ? ? ? ? ? ? ? ?if (err < 0)
> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?ret = err;
> + ? ? ? ? ? ? ? ? ? ? ? EXT4_I(inode)->i_state &= ~EXT4_STATE_DIO_UNWRITTEN;
> ? ? ? ? ? ? ? ?}
> ? ? ? ? ? ? ? ?return ret;
> ? ? ? ?}
>
>
>

2009-10-21 22:48:10

by Mingming Cao

[permalink] [raw]
Subject: Re: [PATCH 2/4 v2] avoid perform unwritten convertion for direct IO over non fallocated space

On Tue, 2009-10-20 at 08:03 -0700, Curt Wohlgemuth wrote:
> Hi Mingming:
>
> On Thu, Oct 8, 2009 at 6:13 PM, Mingming <[email protected]> wrote:
> > ext4: avoid perform unwritten convertion for direct IO over non fallocated space
> >
> > When direct IO complete, without this patch, it always check and convert
> > the range covered by the completed IO to be written. This is unnecessary
> > if the range doesn't has any preallocated area or holes. This patch add
> > a state flag to alart direct IO code to only run the convertion when
> > there is unwritten extents being covered in this IO.
> >
> > Signed-off-by: Mingming Cao <[email protected]>
> > ---
> > fs/ext4/ext4.h | 1 +
> > fs/ext4/extents.c | 22 +++++++++++++++++-----
> > fs/ext4/inode.c | 4 +++-
> > 3 files changed, 21 insertions(+), 6 deletions(-)
> >
> > Index: linux-2.6.31-rc4/fs/ext4/ext4.h
> > ===================================================================
> > --- linux-2.6.31-rc4.orig/fs/ext4/ext4.h
> > +++ linux-2.6.31-rc4/fs/ext4/ext4.h
> > @@ -299,6 +299,7 @@ static inline __u32 ext4_mask_flags(umod
> > #define EXT4_STATE_XATTR 0x00000004 /* has in-inode xattrs */
> > #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_DIO_UNWRITTEN 0x00000020 /* need convert on dio done*/
>
> You'll need to change this value, since EXT4_STATE_EXT_MIGRATE has
> already been assigned 0x20.
>
> Thanks,
> Curt
>
thanks, The patch was originally made on a older kernel, the following
patch is rebased on the new kernel


> >
> > /* Used to pass group descriptor data when online resize is done */
> > struct ext4_new_group_input {
> > Index: linux-2.6.31-rc4/fs/ext4/extents.c
> > ===================================================================
> > --- linux-2.6.31-rc4.orig/fs/ext4/extents.c
> > +++ linux-2.6.31-rc4/fs/ext4/extents.c
> > @@ -3029,12 +3029,18 @@ ext4_ext_handle_uninitialized_extents(ha
> > 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);
> > @@ -3276,10 +3282,16 @@ int ext4_ext_get_blocks(handle_t *handle
> > * 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) {
> > Index: linux-2.6.31-rc4/fs/ext4/inode.c
> > ===================================================================
> > --- linux-2.6.31-rc4.orig/fs/ext4/inode.c
> > +++ linux-2.6.31-rc4/fs/ext4/inode.c
> > @@ -3693,7 +3693,8 @@ static ssize_t ext4_ext_direct_IO(int rw
> > 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
> > @@ -3703,6 +3704,7 @@ static ssize_t ext4_ext_direct_IO(int rw
> > offset, ret);
> > if (err < 0)
> > ret = err;
> > + EXT4_I(inode)->i_state &= ~EXT4_STATE_DIO_UNWRITTEN;
> > }
> > return ret;
> > }
> >
> >
> >
> --
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a


Attachments:
dio-avoid-convertion-for-non-fallocate.patch (3.79 kB)

2009-11-04 02:10:24

by Theodore Ts'o

[permalink] [raw]
Subject: Re: [PATCH 2/4 v2] avoid perform unwritten convertion for direct IO over non fallocated space

I fixed up some white space issues, and rewrote the patch description
as follows:

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 <[email protected]>
Signed-off-by: "Theodore Ts'o" <[email protected]>

Added to the patch queue.

- Ted