linux_dsm_epyc7002/fs/xfs/libxfs/xfs_defer.h
Brian Foster 44fd294681 xfs: pack holes in xfs_defer_ops and xfs_trans
Both structures have holes due to member alignment. Move dop_low to
the end of xfs_defer ops to sanitize the cache line alignment and
move t_flags to save 8 bytes in xfs_trans.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2018-07-26 10:15:13 -07:00

89 lines
3.2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2016 Oracle. All Rights Reserved.
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*/
#ifndef __XFS_DEFER_H__
#define __XFS_DEFER_H__
struct xfs_defer_op_type;
/*
* Save a log intent item and a list of extents, so that we can replay
* whatever action had to happen to the extent list and file the log done
* item.
*/
struct xfs_defer_pending {
const struct xfs_defer_op_type *dfp_type; /* function pointers */
struct list_head dfp_list; /* pending items */
void *dfp_intent; /* log intent item */
void *dfp_done; /* log done item */
struct list_head dfp_work; /* work items */
unsigned int dfp_count; /* # extent items */
};
/*
* Header for deferred operation list.
*
* dop_low is used by the allocator to activate the lowspace algorithm -
* when free space is running low the extent allocator may choose to
* allocate an extent from an AG without leaving sufficient space for
* a btree split when inserting the new extent. In this case the allocator
* will enable the lowspace algorithm which is supposed to allow further
* allocations (such as btree splits and newroots) to allocate from
* sequential AGs. In order to avoid locking AGs out of order the lowspace
* algorithm will start searching for free space from AG 0. If the correct
* transaction reservations have been made then this algorithm will eventually
* find all the space it needs.
*/
enum xfs_defer_ops_type {
XFS_DEFER_OPS_TYPE_BMAP,
XFS_DEFER_OPS_TYPE_REFCOUNT,
XFS_DEFER_OPS_TYPE_RMAP,
XFS_DEFER_OPS_TYPE_FREE,
XFS_DEFER_OPS_TYPE_AGFL_FREE,
XFS_DEFER_OPS_TYPE_MAX,
};
#define XFS_DEFER_OPS_NR_INODES 2 /* join up to two inodes */
#define XFS_DEFER_OPS_NR_BUFS 2 /* join up to two buffers */
struct xfs_defer_ops {
struct list_head dop_intake; /* unlogged pending work */
struct list_head dop_pending; /* logged pending work */
/* relog these with each roll */
struct xfs_inode *dop_inodes[XFS_DEFER_OPS_NR_INODES];
struct xfs_buf *dop_bufs[XFS_DEFER_OPS_NR_BUFS];
bool dop_low; /* alloc in low mode */
};
void xfs_defer_add(struct xfs_defer_ops *dop, enum xfs_defer_ops_type type,
struct list_head *h);
int xfs_defer_finish(struct xfs_trans **tp, struct xfs_defer_ops *dop);
void xfs_defer_cancel(struct xfs_defer_ops *dop);
void xfs_defer_init(struct xfs_trans *tp, struct xfs_defer_ops *dop);
bool xfs_defer_has_unfinished_work(struct xfs_defer_ops *dop);
int xfs_defer_ijoin(struct xfs_defer_ops *dop, struct xfs_inode *ip);
int xfs_defer_bjoin(struct xfs_defer_ops *dop, struct xfs_buf *bp);
/* Description of a deferred type. */
struct xfs_defer_op_type {
enum xfs_defer_ops_type type;
unsigned int max_items;
void (*abort_intent)(void *);
void *(*create_done)(struct xfs_trans *, void *, unsigned int);
int (*finish_item)(struct xfs_trans *, struct xfs_defer_ops *,
struct list_head *, void *, void **);
void (*finish_cleanup)(struct xfs_trans *, void *, int);
void (*cancel_item)(struct list_head *);
int (*diff_items)(void *, struct list_head *, struct list_head *);
void *(*create_intent)(struct xfs_trans *, uint);
void (*log_item)(struct xfs_trans *, void *, struct list_head *);
};
void xfs_defer_init_op_type(const struct xfs_defer_op_type *type);
#endif /* __XFS_DEFER_H__ */