[10/10] xfbtree: let the buffer cache flush dirty buffers to the xfile

Commit Message

Darrick J. Wong Dec. 31, 2023, 10:17 p.m. UTC

From: Darrick J. Wong <[e-mail]>

As a performance optimization, when we're committing xfbtree updates,
let the buffer cache flush the dirty buffers to disk when it's ready
instead of writing everything at every transaction commit.  This is a
bit sketchy but it's an ephemeral tree so we can play fast and loose.

Signed-off-by: Darrick J. Wong <[e-mail]>
---
 libxfs/xfbtree.c |   17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

Patch

diff --git a/libxfs/xfbtree.c b/libxfs/xfbtree.c
index 3cca7b5494c..c4dd706f4f7 100644
--- a/libxfs/xfbtree.c
+++ b/libxfs/xfbtree.c
@@ -699,7 +699,6 @@  xfbtree_trans_commit(
 	struct xfbtree		*xfbt,
 	struct xfs_trans	*tp)
 {
-	LIST_HEAD(buffer_list);
 	struct xfs_log_item	*lip, *n;
 	bool			corrupt = false;
 	bool			tp_dirty = false;
@@ -733,12 +732,16 @@  xfbtree_trans_commit(
 			 * If the buffer fails verification, log the failure
 			 * but continue walking the transaction items so that
 			 * we remove all ephemeral btree buffers.
+			 *
+			 * Since the userspace buffer cache supports marking
+			 * buffers dirty and flushing them later, use this to
+			 * reduce the number of writes to the xfile.
 			 */
 			if (fa) {
 				corrupt = true;
 				xfs_verifier_error(bp, -EFSCORRUPTED, fa);
 			} else {
-				xfs_buf_delwri_queue_here(bp, &buffer_list);
+				libxfs_buf_mark_dirty(bp);
 			}
 		}
 
@@ -752,15 +755,9 @@  xfbtree_trans_commit(
 	tp->t_flags = (tp->t_flags & ~XFS_TRANS_DIRTY) |
 			(tp_dirty ? XFS_TRANS_DIRTY : 0);
 
-	if (corrupt) {
-		xfs_buf_delwri_cancel(&buffer_list);
+	if (corrupt)
 		return -EFSCORRUPTED;
-	}
-
-	if (list_empty(&buffer_list))
-		return 0;
-
-	return xfs_buf_delwri_submit(&buffer_list);
+	return 0;
 }
 
 /*