[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <4FA0B400.3090706@tao.ma>
Date: Wed, 02 May 2012 12:11:44 +0800
From: Tao Ma <tm@....ma>
To: Zheng Liu <gnehzuil.liu@...il.com>
CC: linux-ext4@...r.kernel.org
Subject: Re: [RFC][PATCH 1/3] ext4: split ext4_file_write into buffered IO
and direct IO
Hi zheng,
On 04/28/2012 11:39 AM, Zheng Liu wrote:
> From: Zheng Liu <wenqing.lz@...bao.com>
>
> ext4_file_buffered/direct_write are defined in order to split buffered IO and
> direct IO in ext4. This patch just refactor some stuff in write path.
>
> Signed-off-by: Zheng Liu <wenqing.lz@...bao.com>
> ---
> fs/ext4/file.c | 66 +++++++++++++++++++++++++++++++++++++------------------
> 1 files changed, 44 insertions(+), 22 deletions(-)
>
> diff --git a/fs/ext4/file.c b/fs/ext4/file.c
> index cb70f18..e5d6be3 100644
> --- a/fs/ext4/file.c
> +++ b/fs/ext4/file.c
> @@ -89,12 +89,51 @@ ext4_unaligned_aio(struct inode *inode, const struct iovec *iov,
> return 0;
> }
>
> +static inline ssize_t
> +ext4_file_buffered_write(struct kiocb *iocb, const struct iovec *iov,
> + unsigned long nr_segs, loff_t pos)
> +{
> + return generic_file_aio_write(iocb, iov, nr_segs, pos);
> +}
any reason you wrap generic_file_aio_write with a new function? I didn't
see you use it in the following patch either.
Thanks
Tao
> +
> +static ssize_t
> +ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
> + unsigned long nr_segs, loff_t pos)
> +{
> + struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
> + int unaligned_aio = 0;
> + ssize_t ret;
> +
> + if (!is_sync_kiocb(iocb))
> + unaligned_aio = ext4_unaligned_aio(inode, iov, nr_segs, pos);
> +
> + /* Unaligned direct AIO must be serialized; see comment above */
> + if (unaligned_aio) {
> + static unsigned long unaligned_warn_time;
> +
> + /* Warn about this once per day */
> + if (printk_timed_ratelimit(&unaligned_warn_time, 60*60*24*HZ))
> + ext4_msg(inode->i_sb, KERN_WARNING,
> + "Unaligned AIO/DIO on inode %ld by %s; "
> + "performance will be poor.",
> + inode->i_ino, current->comm);
> + mutex_lock(ext4_aio_mutex(inode));
> + ext4_aiodio_wait(inode);
> + }
> +
> + ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
> +
> + if (unaligned_aio)
> + mutex_unlock(ext4_aio_mutex(inode));
> +
> + return ret;
> +}
> +
> static ssize_t
> ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
> unsigned long nr_segs, loff_t pos)
> {
> struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
> - int unaligned_aio = 0;
> int ret;
>
> /*
> @@ -114,29 +153,12 @@ ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
> nr_segs = iov_shorten((struct iovec *)iov, nr_segs,
> sbi->s_bitmap_maxbytes - pos);
> }
> - } else if (unlikely((iocb->ki_filp->f_flags & O_DIRECT) &&
> - !is_sync_kiocb(iocb))) {
> - unaligned_aio = ext4_unaligned_aio(inode, iov, nr_segs, pos);
> - }
> -
> - /* Unaligned direct AIO must be serialized; see comment above */
> - if (unaligned_aio) {
> - static unsigned long unaligned_warn_time;
> -
> - /* Warn about this once per day */
> - if (printk_timed_ratelimit(&unaligned_warn_time, 60*60*24*HZ))
> - ext4_msg(inode->i_sb, KERN_WARNING,
> - "Unaligned AIO/DIO on inode %ld by %s; "
> - "performance will be poor.",
> - inode->i_ino, current->comm);
> - mutex_lock(ext4_aio_mutex(inode));
> - ext4_aiodio_wait(inode);
> }
>
> - ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
> -
> - if (unaligned_aio)
> - mutex_unlock(ext4_aio_mutex(inode));
> + if (unlikely(iocb->ki_filp->f_flags & O_DIRECT))
> + ret = ext4_file_dio_write(iocb, iov, nr_segs, pos);
> + else
> + ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
>
> return ret;
> }
--
To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists