Commit 26de6462 authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: read leaf blocks when computing keys for bulkloading into node blocks 



When constructing a new btree, xfs_btree_bload_node needs to read the
btree blocks for level N to compute the keyptrs for the blocks that will
be loaded into level N+1.  The level N blocks must be formatted at that
point.

A subsequent patch will change the btree bulkloader to write new btree
blocks in 256K chunks to moderate memory consumption if the new btree is
very large.  As a consequence of that, it's possible that the buffers
for lower level blocks might have been reclaimed by the time the node
builder comes back to the block.

Therefore, change xfs_btree_bload_node to read the lower level blocks
to handle the reclaimed buffer case.  As a side effect, the read will
increase the LRU refs, which will bias towards keeping new btree buffers
in memory after the new btree commits.

Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
parent c1e0f8e6

fs/xfs/libxfs/xfs_btree.c

+1 −1
Original line number Diff line number Diff line
@@ -1330,7 +1330,7 @@ xfs_btree_get_buf_block( 
 * Read in the buffer at the given ptr and return the buffer and

 * the block pointer within the buffer.

 */

STATIC int

int

xfs_btree_read_buf_block(

	struct xfs_btree_cur		*cur,

	const union xfs_btree_ptr	*ptr,

fs/xfs/libxfs/xfs_btree.h

+3 −0
Original line number Diff line number Diff line
@@ -700,6 +700,9 @@ void xfs_btree_set_ptr_null(struct xfs_btree_cur *cur, 
int xfs_btree_get_buf_block(struct xfs_btree_cur *cur,

		const union xfs_btree_ptr *ptr, struct xfs_btree_block **block,

		struct xfs_buf **bpp);

int xfs_btree_read_buf_block(struct xfs_btree_cur *cur,

		const union xfs_btree_ptr *ptr, int flags,

		struct xfs_btree_block **block, struct xfs_buf **bpp);

void xfs_btree_set_sibling(struct xfs_btree_cur *cur,

		struct xfs_btree_block *block, const union xfs_btree_ptr *ptr,

		int lr);

fs/xfs/libxfs/xfs_btree_staging.c

+6 −1
Original line number Diff line number Diff line
@@ -489,7 +489,12 @@ xfs_btree_bload_node( 


		ASSERT(!xfs_btree_ptr_is_null(cur, child_ptr));



		ret = xfs_btree_get_buf_block(cur, child_ptr, &child_block,

		/*

		 * Read the lower-level block in case the buffer for it has

		 * been reclaimed.  LRU refs will be set on the block, which is

		 * desirable if the new btree commits.

		 */

		ret = xfs_btree_read_buf_block(cur, child_ptr, 0, &child_block,

				&child_bp);

		if (ret)

			return ret;