mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 10:40:15 +02:00 
			
		
		
		
	In doing an investigation into AIL push stalls, I was looking at the log force code to see if an async CIL push could be done instead. This lead me to xfs_log_force_lsn() and looking at how it works. xfs_log_force_lsn() is only called from inode synchronisation contexts such as fsync(), and it takes the ip->i_itemp->ili_last_lsn value as the LSN to sync the log to. This gets passed to xlog_cil_force_lsn() via xfs_log_force_lsn() to flush the CIL to the journal, and then used by xfs_log_force_lsn() to flush the iclogs to the journal. The problem is that ip->i_itemp->ili_last_lsn does not store a log sequence number. What it stores is passed to it from the ->iop_committing method, which is called by xfs_log_commit_cil(). The value this passes to the iop_committing method is the CIL context sequence number that the item was committed to. As it turns out, xlog_cil_force_lsn() converts the sequence to an actual commit LSN for the related context and returns that to xfs_log_force_lsn(). xfs_log_force_lsn() overwrites it's "lsn" variable that contained a sequence with an actual LSN and then uses that to sync the iclogs. This caused me some confusion for a while, even though I originally wrote all this code a decade ago. ->iop_committing is only used by a couple of log item types, and only inode items use the sequence number it is passed. Let's clean up the API, CIL structures and inode log item to call it a sequence number, and make it clear that the high level code is using CIL sequence numbers and not on-disk LSNs for integrity synchronisation purposes. Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Allison Henderson <allison.henderson@oracle.com> Signed-off-by: Darrick J. Wong <djwong@kernel.org>
		
			
				
	
	
		
			299 lines
		
	
	
	
		
			9.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			299 lines
		
	
	
	
		
			9.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
 | 
						|
/*
 | 
						|
 * Copyright (c) 2000-2002,2005 Silicon Graphics, Inc.
 | 
						|
 * All Rights Reserved.
 | 
						|
 */
 | 
						|
#ifndef	__XFS_TRANS_H__
 | 
						|
#define	__XFS_TRANS_H__
 | 
						|
 | 
						|
/* kernel only transaction subsystem defines */
 | 
						|
 | 
						|
struct xfs_buf;
 | 
						|
struct xfs_buftarg;
 | 
						|
struct xfs_efd_log_item;
 | 
						|
struct xfs_efi_log_item;
 | 
						|
struct xfs_inode;
 | 
						|
struct xfs_item_ops;
 | 
						|
struct xfs_log_iovec;
 | 
						|
struct xfs_mount;
 | 
						|
struct xfs_trans;
 | 
						|
struct xfs_trans_res;
 | 
						|
struct xfs_dquot_acct;
 | 
						|
struct xfs_rud_log_item;
 | 
						|
struct xfs_rui_log_item;
 | 
						|
struct xfs_btree_cur;
 | 
						|
struct xfs_cui_log_item;
 | 
						|
struct xfs_cud_log_item;
 | 
						|
struct xfs_bui_log_item;
 | 
						|
struct xfs_bud_log_item;
 | 
						|
 | 
						|
struct xfs_log_item {
 | 
						|
	struct list_head		li_ail;		/* AIL pointers */
 | 
						|
	struct list_head		li_trans;	/* transaction list */
 | 
						|
	xfs_lsn_t			li_lsn;		/* last on-disk lsn */
 | 
						|
	struct xfs_mount		*li_mountp;	/* ptr to fs mount */
 | 
						|
	struct xfs_ail			*li_ailp;	/* ptr to AIL */
 | 
						|
	uint				li_type;	/* item type */
 | 
						|
	unsigned long			li_flags;	/* misc flags */
 | 
						|
	struct xfs_buf			*li_buf;	/* real buffer pointer */
 | 
						|
	struct list_head		li_bio_list;	/* buffer item list */
 | 
						|
	const struct xfs_item_ops	*li_ops;	/* function list */
 | 
						|
 | 
						|
	/* delayed logging */
 | 
						|
	struct list_head		li_cil;		/* CIL pointers */
 | 
						|
	struct xfs_log_vec		*li_lv;		/* active log vector */
 | 
						|
	struct xfs_log_vec		*li_lv_shadow;	/* standby vector */
 | 
						|
	xfs_csn_t			li_seq;		/* CIL commit seq */
 | 
						|
};
 | 
						|
 | 
						|
/*
 | 
						|
 * li_flags use the (set/test/clear)_bit atomic interfaces because updates can
 | 
						|
 * race with each other and we don't want to have to use the AIL lock to
 | 
						|
 * serialise all updates.
 | 
						|
 */
 | 
						|
#define	XFS_LI_IN_AIL	0
 | 
						|
#define	XFS_LI_ABORTED	1
 | 
						|
#define	XFS_LI_FAILED	2
 | 
						|
#define	XFS_LI_DIRTY	3	/* log item dirty in transaction */
 | 
						|
 | 
						|
#define XFS_LI_FLAGS \
 | 
						|
	{ (1 << XFS_LI_IN_AIL),		"IN_AIL" }, \
 | 
						|
	{ (1 << XFS_LI_ABORTED),	"ABORTED" }, \
 | 
						|
	{ (1 << XFS_LI_FAILED),		"FAILED" }, \
 | 
						|
	{ (1 << XFS_LI_DIRTY),		"DIRTY" }
 | 
						|
 | 
						|
struct xfs_item_ops {
 | 
						|
	unsigned flags;
 | 
						|
	void (*iop_size)(struct xfs_log_item *, int *, int *);
 | 
						|
	void (*iop_format)(struct xfs_log_item *, struct xfs_log_vec *);
 | 
						|
	void (*iop_pin)(struct xfs_log_item *);
 | 
						|
	void (*iop_unpin)(struct xfs_log_item *, int remove);
 | 
						|
	uint (*iop_push)(struct xfs_log_item *, struct list_head *);
 | 
						|
	void (*iop_committing)(struct xfs_log_item *lip, xfs_csn_t seq);
 | 
						|
	void (*iop_release)(struct xfs_log_item *);
 | 
						|
	xfs_lsn_t (*iop_committed)(struct xfs_log_item *, xfs_lsn_t);
 | 
						|
	int (*iop_recover)(struct xfs_log_item *lip,
 | 
						|
			   struct list_head *capture_list);
 | 
						|
	bool (*iop_match)(struct xfs_log_item *item, uint64_t id);
 | 
						|
	struct xfs_log_item *(*iop_relog)(struct xfs_log_item *intent,
 | 
						|
			struct xfs_trans *tp);
 | 
						|
};
 | 
						|
 | 
						|
/* Is this log item a deferred action intent? */
 | 
						|
static inline bool
 | 
						|
xlog_item_is_intent(struct xfs_log_item *lip)
 | 
						|
{
 | 
						|
	return lip->li_ops->iop_recover != NULL &&
 | 
						|
	       lip->li_ops->iop_match != NULL;
 | 
						|
}
 | 
						|
 | 
						|
/* Is this a log intent-done item? */
 | 
						|
static inline bool
 | 
						|
xlog_item_is_intent_done(struct xfs_log_item *lip)
 | 
						|
{
 | 
						|
	return lip->li_ops->iop_unpin == NULL &&
 | 
						|
	       lip->li_ops->iop_push == NULL;
 | 
						|
}
 | 
						|
 | 
						|
/*
 | 
						|
 * Release the log item as soon as committed.  This is for items just logging
 | 
						|
 * intents that never need to be written back in place.
 | 
						|
 */
 | 
						|
#define XFS_ITEM_RELEASE_WHEN_COMMITTED	(1 << 0)
 | 
						|
 | 
						|
void	xfs_log_item_init(struct xfs_mount *mp, struct xfs_log_item *item,
 | 
						|
			  int type, const struct xfs_item_ops *ops);
 | 
						|
 | 
						|
/*
 | 
						|
 * Return values for the iop_push() routines.
 | 
						|
 */
 | 
						|
#define XFS_ITEM_SUCCESS	0
 | 
						|
#define XFS_ITEM_PINNED		1
 | 
						|
#define XFS_ITEM_LOCKED		2
 | 
						|
#define XFS_ITEM_FLUSHING	3
 | 
						|
 | 
						|
/*
 | 
						|
 * Deferred operation item relogging limits.
 | 
						|
 */
 | 
						|
#define XFS_DEFER_OPS_NR_INODES	2	/* join up to two inodes */
 | 
						|
#define XFS_DEFER_OPS_NR_BUFS	2	/* join up to two buffers */
 | 
						|
 | 
						|
/*
 | 
						|
 * This is the structure maintained for every active transaction.
 | 
						|
 */
 | 
						|
typedef struct xfs_trans {
 | 
						|
	unsigned int		t_magic;	/* magic number */
 | 
						|
	unsigned int		t_log_res;	/* amt of log space resvd */
 | 
						|
	unsigned int		t_log_count;	/* count for perm log res */
 | 
						|
	unsigned int		t_blk_res;	/* # of blocks resvd */
 | 
						|
	unsigned int		t_blk_res_used;	/* # of resvd blocks used */
 | 
						|
	unsigned int		t_rtx_res;	/* # of rt extents resvd */
 | 
						|
	unsigned int		t_rtx_res_used;	/* # of resvd rt extents used */
 | 
						|
	unsigned int		t_flags;	/* misc flags */
 | 
						|
	xfs_fsblock_t		t_firstblock;	/* first block allocated */
 | 
						|
	struct xlog_ticket	*t_ticket;	/* log mgr ticket */
 | 
						|
	struct xfs_mount	*t_mountp;	/* ptr to fs mount struct */
 | 
						|
	struct xfs_dquot_acct   *t_dqinfo;	/* acctg info for dquots */
 | 
						|
	int64_t			t_icount_delta;	/* superblock icount change */
 | 
						|
	int64_t			t_ifree_delta;	/* superblock ifree change */
 | 
						|
	int64_t			t_fdblocks_delta; /* superblock fdblocks chg */
 | 
						|
	int64_t			t_res_fdblocks_delta; /* on-disk only chg */
 | 
						|
	int64_t			t_frextents_delta;/* superblock freextents chg*/
 | 
						|
	int64_t			t_res_frextents_delta; /* on-disk only chg */
 | 
						|
	int64_t			t_dblocks_delta;/* superblock dblocks change */
 | 
						|
	int64_t			t_agcount_delta;/* superblock agcount change */
 | 
						|
	int64_t			t_imaxpct_delta;/* superblock imaxpct change */
 | 
						|
	int64_t			t_rextsize_delta;/* superblock rextsize chg */
 | 
						|
	int64_t			t_rbmblocks_delta;/* superblock rbmblocks chg */
 | 
						|
	int64_t			t_rblocks_delta;/* superblock rblocks change */
 | 
						|
	int64_t			t_rextents_delta;/* superblocks rextents chg */
 | 
						|
	int64_t			t_rextslog_delta;/* superblocks rextslog chg */
 | 
						|
	struct list_head	t_items;	/* log item descriptors */
 | 
						|
	struct list_head	t_busy;		/* list of busy extents */
 | 
						|
	struct list_head	t_dfops;	/* deferred operations */
 | 
						|
	unsigned long		t_pflags;	/* saved process flags state */
 | 
						|
} xfs_trans_t;
 | 
						|
 | 
						|
/*
 | 
						|
 * XFS transaction mechanism exported interfaces that are
 | 
						|
 * actually macros.
 | 
						|
 */
 | 
						|
#define	xfs_trans_set_sync(tp)		((tp)->t_flags |= XFS_TRANS_SYNC)
 | 
						|
 | 
						|
/*
 | 
						|
 * XFS transaction mechanism exported interfaces.
 | 
						|
 */
 | 
						|
int		xfs_trans_alloc(struct xfs_mount *mp, struct xfs_trans_res *resp,
 | 
						|
			uint blocks, uint rtextents, uint flags,
 | 
						|
			struct xfs_trans **tpp);
 | 
						|
int		xfs_trans_alloc_empty(struct xfs_mount *mp,
 | 
						|
			struct xfs_trans **tpp);
 | 
						|
void		xfs_trans_mod_sb(xfs_trans_t *, uint, int64_t);
 | 
						|
 | 
						|
int xfs_trans_get_buf_map(struct xfs_trans *tp, struct xfs_buftarg *target,
 | 
						|
		struct xfs_buf_map *map, int nmaps, xfs_buf_flags_t flags,
 | 
						|
		struct xfs_buf **bpp);
 | 
						|
 | 
						|
static inline int
 | 
						|
xfs_trans_get_buf(
 | 
						|
	struct xfs_trans	*tp,
 | 
						|
	struct xfs_buftarg	*target,
 | 
						|
	xfs_daddr_t		blkno,
 | 
						|
	int			numblks,
 | 
						|
	uint			flags,
 | 
						|
	struct xfs_buf		**bpp)
 | 
						|
{
 | 
						|
	DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
 | 
						|
	return xfs_trans_get_buf_map(tp, target, &map, 1, flags, bpp);
 | 
						|
}
 | 
						|
 | 
						|
int		xfs_trans_read_buf_map(struct xfs_mount *mp,
 | 
						|
				       struct xfs_trans *tp,
 | 
						|
				       struct xfs_buftarg *target,
 | 
						|
				       struct xfs_buf_map *map, int nmaps,
 | 
						|
				       xfs_buf_flags_t flags,
 | 
						|
				       struct xfs_buf **bpp,
 | 
						|
				       const struct xfs_buf_ops *ops);
 | 
						|
 | 
						|
static inline int
 | 
						|
xfs_trans_read_buf(
 | 
						|
	struct xfs_mount	*mp,
 | 
						|
	struct xfs_trans	*tp,
 | 
						|
	struct xfs_buftarg	*target,
 | 
						|
	xfs_daddr_t		blkno,
 | 
						|
	int			numblks,
 | 
						|
	xfs_buf_flags_t		flags,
 | 
						|
	struct xfs_buf		**bpp,
 | 
						|
	const struct xfs_buf_ops *ops)
 | 
						|
{
 | 
						|
	DEFINE_SINGLE_BUF_MAP(map, blkno, numblks);
 | 
						|
	return xfs_trans_read_buf_map(mp, tp, target, &map, 1,
 | 
						|
				      flags, bpp, ops);
 | 
						|
}
 | 
						|
 | 
						|
struct xfs_buf	*xfs_trans_getsb(struct xfs_trans *);
 | 
						|
 | 
						|
void		xfs_trans_brelse(xfs_trans_t *, struct xfs_buf *);
 | 
						|
void		xfs_trans_bjoin(xfs_trans_t *, struct xfs_buf *);
 | 
						|
void		xfs_trans_bhold(xfs_trans_t *, struct xfs_buf *);
 | 
						|
void		xfs_trans_bhold_release(xfs_trans_t *, struct xfs_buf *);
 | 
						|
void		xfs_trans_binval(xfs_trans_t *, struct xfs_buf *);
 | 
						|
void		xfs_trans_inode_buf(xfs_trans_t *, struct xfs_buf *);
 | 
						|
void		xfs_trans_stale_inode_buf(xfs_trans_t *, struct xfs_buf *);
 | 
						|
bool		xfs_trans_ordered_buf(xfs_trans_t *, struct xfs_buf *);
 | 
						|
void		xfs_trans_dquot_buf(xfs_trans_t *, struct xfs_buf *, uint);
 | 
						|
void		xfs_trans_inode_alloc_buf(xfs_trans_t *, struct xfs_buf *);
 | 
						|
void		xfs_trans_ichgtime(struct xfs_trans *, struct xfs_inode *, int);
 | 
						|
void		xfs_trans_ijoin(struct xfs_trans *, struct xfs_inode *, uint);
 | 
						|
void		xfs_trans_log_buf(struct xfs_trans *, struct xfs_buf *, uint,
 | 
						|
				  uint);
 | 
						|
void		xfs_trans_dirty_buf(struct xfs_trans *, struct xfs_buf *);
 | 
						|
bool		xfs_trans_buf_is_dirty(struct xfs_buf *bp);
 | 
						|
void		xfs_trans_log_inode(xfs_trans_t *, struct xfs_inode *, uint);
 | 
						|
 | 
						|
int		xfs_trans_commit(struct xfs_trans *);
 | 
						|
int		xfs_trans_roll(struct xfs_trans **);
 | 
						|
int		xfs_trans_roll_inode(struct xfs_trans **, struct xfs_inode *);
 | 
						|
void		xfs_trans_cancel(xfs_trans_t *);
 | 
						|
int		xfs_trans_ail_init(struct xfs_mount *);
 | 
						|
void		xfs_trans_ail_destroy(struct xfs_mount *);
 | 
						|
 | 
						|
void		xfs_trans_buf_set_type(struct xfs_trans *, struct xfs_buf *,
 | 
						|
				       enum xfs_blft);
 | 
						|
void		xfs_trans_buf_copy_type(struct xfs_buf *dst_bp,
 | 
						|
					struct xfs_buf *src_bp);
 | 
						|
 | 
						|
extern kmem_zone_t	*xfs_trans_zone;
 | 
						|
 | 
						|
static inline struct xfs_log_item *
 | 
						|
xfs_trans_item_relog(
 | 
						|
	struct xfs_log_item	*lip,
 | 
						|
	struct xfs_trans	*tp)
 | 
						|
{
 | 
						|
	return lip->li_ops->iop_relog(lip, tp);
 | 
						|
}
 | 
						|
 | 
						|
struct xfs_dquot;
 | 
						|
 | 
						|
int xfs_trans_alloc_inode(struct xfs_inode *ip, struct xfs_trans_res *resv,
 | 
						|
		unsigned int dblocks, unsigned int rblocks, bool force,
 | 
						|
		struct xfs_trans **tpp);
 | 
						|
int xfs_trans_alloc_icreate(struct xfs_mount *mp, struct xfs_trans_res *resv,
 | 
						|
		struct xfs_dquot *udqp, struct xfs_dquot *gdqp,
 | 
						|
		struct xfs_dquot *pdqp, unsigned int dblocks,
 | 
						|
		struct xfs_trans **tpp);
 | 
						|
int xfs_trans_alloc_ichange(struct xfs_inode *ip, struct xfs_dquot *udqp,
 | 
						|
		struct xfs_dquot *gdqp, struct xfs_dquot *pdqp, bool force,
 | 
						|
		struct xfs_trans **tpp);
 | 
						|
 | 
						|
static inline void
 | 
						|
xfs_trans_set_context(
 | 
						|
	struct xfs_trans	*tp)
 | 
						|
{
 | 
						|
	ASSERT(current->journal_info == NULL);
 | 
						|
	tp->t_pflags = memalloc_nofs_save();
 | 
						|
	current->journal_info = tp;
 | 
						|
}
 | 
						|
 | 
						|
static inline void
 | 
						|
xfs_trans_clear_context(
 | 
						|
	struct xfs_trans	*tp)
 | 
						|
{
 | 
						|
	if (current->journal_info == tp) {
 | 
						|
		memalloc_nofs_restore(tp->t_pflags);
 | 
						|
		current->journal_info = NULL;
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
static inline void
 | 
						|
xfs_trans_switch_context(
 | 
						|
	struct xfs_trans	*old_tp,
 | 
						|
	struct xfs_trans	*new_tp)
 | 
						|
{
 | 
						|
	ASSERT(current->journal_info == old_tp);
 | 
						|
	new_tp->t_pflags = old_tp->t_pflags;
 | 
						|
	old_tp->t_pflags = 0;
 | 
						|
	current->journal_info = new_tp;
 | 
						|
}
 | 
						|
 | 
						|
#endif	/* __XFS_TRANS_H__ */
 |