From d808f617ad00a413585b806de340feda5ad9a2da Mon Sep 17 00:00:00 2001 From: Dave Chinner Date: Tue, 2 Feb 2010 10:13:42 +1100 Subject: xfs: Don't issue buffer IO direct from AIL push V2 All buffers logged into the AIL are marked as delayed write. When the AIL needs to push the buffer out, it issues an async write of the buffer. This means that IO patterns are dependent on the order of buffers in the AIL. Instead of flushing the buffer, promote the buffer in the delayed write list so that the next time the xfsbufd is run the buffer will be flushed by the xfsbufd. Return the state to the xfsaild that the buffer was promoted so that the xfsaild knows that it needs to cause the xfsbufd to run to flush the buffers that were promoted. Using the xfsbufd for issuing the IO allows us to dispatch all buffer IO from the one queue. This means that we can make much more enlightened decisions on what order to flush buffers to disk as we don't have multiple places issuing IO. Optimisations to xfsbufd will be in a future patch. Version 2 - kill XFS_ITEM_FLUSHING as it is now unused. Signed-off-by: Dave Chinner Reviewed-by: Christoph Hellwig --- fs/xfs/xfs_trans.h | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs/xfs/xfs_trans.h') diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h index ca64f33c63a3..c93e3a102857 100644 --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -861,8 +861,7 @@ typedef struct xfs_item_ops { #define XFS_ITEM_SUCCESS 0 #define XFS_ITEM_PINNED 1 #define XFS_ITEM_LOCKED 2 -#define XFS_ITEM_FLUSHING 3 -#define XFS_ITEM_PUSHBUF 4 +#define XFS_ITEM_PUSHBUF 3 /* * This structure is used to maintain a list of block ranges that have been -- cgit v1.2.3