From 7b7a8665edd8db733980389b098530f9e4f630b2 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 4 Sep 2013 15:04:39 +0200 Subject: direct-io: Implement generic deferred AIO completions Add support to the core direct-io code to defer AIO completions to user context using a workqueue. This replaces opencoded and less efficient code in XFS and ext4 (we save a memory allocation for each direct IO) and will be needed to properly support O_(D)SYNC for AIO. The communication between the filesystem and the direct I/O code requires a new buffer head flag, which is a bit ugly but not avoidable until the direct I/O code stops abusing the buffer_head structure for communicating with the filesystems. Currently this creates a per-superblock unbound workqueue for these completions, which is taken from an earlier patch by Jan Kara. I'm not really convinced about this use and would prefer a "normal" global workqueue with a high concurrency limit, but this needs further discussion. JK: Fixed ext4 part, dynamic allocation of the workqueue. Signed-off-by: Christoph Hellwig Signed-off-by: Jan Kara Signed-off-by: Al Viro --- fs/ext4/page-io.c | 30 +++++++----------------------- 1 file changed, 7 insertions(+), 23 deletions(-) (limited to 'fs/ext4/page-io.c') diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index 6625d210fb45..d7d0c7b46ed4 100644 --- a/fs/ext4/page-io.c +++ b/fs/ext4/page-io.c @@ -123,10 +123,6 @@ static void ext4_release_io_end(ext4_io_end_t *io_end) ext4_finish_bio(bio); bio_put(bio); } - if (io_end->flag & EXT4_IO_END_DIRECT) - inode_dio_done(io_end->inode); - if (io_end->iocb) - aio_complete(io_end->iocb, io_end->result, 0); kmem_cache_free(io_end_cachep, io_end); } @@ -204,19 +200,14 @@ static void ext4_add_complete_io(ext4_io_end_t *io_end) struct workqueue_struct *wq; unsigned long flags; - BUG_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN)); + /* Only reserved conversions from writeback should enter here */ + WARN_ON(!(io_end->flag & EXT4_IO_END_UNWRITTEN)); + WARN_ON(!io_end->handle); spin_lock_irqsave(&ei->i_completed_io_lock, flags); - if (io_end->handle) { - wq = EXT4_SB(io_end->inode->i_sb)->rsv_conversion_wq; - if (list_empty(&ei->i_rsv_conversion_list)) - queue_work(wq, &ei->i_rsv_conversion_work); - list_add_tail(&io_end->list, &ei->i_rsv_conversion_list); - } else { - wq = EXT4_SB(io_end->inode->i_sb)->unrsv_conversion_wq; - if (list_empty(&ei->i_unrsv_conversion_list)) - queue_work(wq, &ei->i_unrsv_conversion_work); - list_add_tail(&io_end->list, &ei->i_unrsv_conversion_list); - } + wq = EXT4_SB(io_end->inode->i_sb)->rsv_conversion_wq; + if (list_empty(&ei->i_rsv_conversion_list)) + queue_work(wq, &ei->i_rsv_conversion_work); + list_add_tail(&io_end->list, &ei->i_rsv_conversion_list); spin_unlock_irqrestore(&ei->i_completed_io_lock, flags); } @@ -256,13 +247,6 @@ void ext4_end_io_rsv_work(struct work_struct *work) ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_rsv_conversion_list); } -void ext4_end_io_unrsv_work(struct work_struct *work) -{ - struct ext4_inode_info *ei = container_of(work, struct ext4_inode_info, - i_unrsv_conversion_work); - ext4_do_flush_completed_IO(&ei->vfs_inode, &ei->i_unrsv_conversion_list); -} - ext4_io_end_t *ext4_init_io_end(struct inode *inode, gfp_t flags) { ext4_io_end_t *io = kmem_cache_zalloc(io_end_cachep, flags); -- cgit v1.2.3-59-g8ed1b