linux/fs/xfs/scrub/trace.c
Darrick J. Wong 3934e8ebb7 xfs: create a big array data structure
Create a simple 'big array' data structure for storage of fixed-size
metadata records that will be used to reconstruct a btree index.  For
repair operations, the most important operations are append, iterate,
and sort.

Earlier implementations of the big array used linked lists and suffered
from severe problems -- pinning all records in kernel memory was not a
good idea and frequently lead to OOM situations; random access was very
inefficient; and record overhead for the lists was unacceptably high at
40-60%.

Therefore, the big memory array relies on the 'xfile' abstraction, which
creates a memfd file and stores the records in page cache pages.  Since
the memfd is created in tmpfs, the memory pages can be pushed out to
disk if necessary and we have a built-in usage limit of 50% of physical
memory.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Kent Overstreet <kent.overstreet@linux.dev>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2023-08-10 07:48:04 -07:00

43 lines
1.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2017-2023 Oracle. All Rights Reserved.
* Author: Darrick J. Wong <djwong@kernel.org>
*/
#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_shared.h"
#include "xfs_format.h"
#include "xfs_log_format.h"
#include "xfs_trans_resv.h"
#include "xfs_mount.h"
#include "xfs_inode.h"
#include "xfs_btree.h"
#include "xfs_ag.h"
#include "scrub/scrub.h"
#include "scrub/xfile.h"
#include "scrub/xfarray.h"
/* Figure out which block the btree cursor was pointing to. */
static inline xfs_fsblock_t
xchk_btree_cur_fsbno(
struct xfs_btree_cur *cur,
int level)
{
if (level < cur->bc_nlevels && cur->bc_levels[level].bp)
return XFS_DADDR_TO_FSB(cur->bc_mp,
xfs_buf_daddr(cur->bc_levels[level].bp));
if (level == cur->bc_nlevels - 1 &&
(cur->bc_flags & XFS_BTREE_ROOT_IN_INODE))
return XFS_INO_TO_FSB(cur->bc_mp, cur->bc_ino.ip->i_ino);
return NULLFSBLOCK;
}
/*
* We include this last to have the helpers above available for the trace
* event implementations.
*/
#define CREATE_TRACE_POINTS
#include "scrub/trace.h"