xfs: check tp->t_dqinfo value instead of the XFS_TRANS_DQ_DIRTY flag

Nowadays the only things that the XFS_TRANS_DQ_DIRTY flag seems to do
are indicates the tp->t_dqinfo->dqs[XFS_QM_TRANS_{USR,GRP,PRJ}] values
changed and check in xfs_trans_apply_dquot_deltas() and the unreserve
variant xfs_trans_unreserve_and_mod_dquots(). Actually, we also can
use the tp->t_dqinfo value instead of the XFS_TRANS_DQ_DIRTY flag, that
is to say, we allocate the new tp->t_dqinfo only when the qtrx values
changed, so the tp->t_dqinfo value isn't NULL equals the XFS_TRANS_DQ_DIRTY
flag is set, we only need to check if tp->t_dqinfo == NULL in
xfs_trans_apply_dquot_deltas() and its unreserve variant to determine
whether lock all of the dquots and join them to the transaction.

Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

fs/xfs/libxfs/xfs_shared.h

@@ -62,7 +62,6 @@ void	xfs_log_get_max_trans_res(struct xfs_mount *mp,
 #define	XFS_TRANS_SB_DIRTY	0x02	/* superblock is modified */
 #define	XFS_TRANS_PERM_LOG_RES	0x04	/* xact took a permanent log res */
 #define	XFS_TRANS_SYNC		0x08	/* make commit synchronous */
-#define XFS_TRANS_DQ_DIRTY	0x10	/* at least one dquot in trx dirty */
 #define XFS_TRANS_RESERVE	0x20    /* OK to use reserved data blocks */
 #define XFS_TRANS_NO_WRITECOUNT 0x40	/* do not elevate SB writecount */
 #define XFS_TRANS_RES_FDBLKS	0x80	/* reserve newly freed blocks */

fs/xfs/xfs_inode.c

@@ -959,7 +959,6 @@ xfs_dir_ialloc(
 	xfs_buf_t	*ialloc_context = NULL;
 	int		code;
 	void		*dqinfo;
-	uint		tflags;
 
 	tp = *tpp;
 	ASSERT(tp->t_flags & XFS_TRANS_PERM_LOG_RES);
@@ -1018,23 +1017,18 @@ xfs_dir_ialloc(
 		 * and attach it to the next transaction.
 		 */
 		dqinfo = NULL;
-		tflags = 0;
 		if (tp->t_dqinfo) {
 			dqinfo = (void *)tp->t_dqinfo;
 			tp->t_dqinfo = NULL;
-			tflags = tp->t_flags & XFS_TRANS_DQ_DIRTY;
-			tp->t_flags &= ~(XFS_TRANS_DQ_DIRTY);
 		}
 
 		code = xfs_trans_roll(&tp);
 
 		/*
 		 * Re-attach the quota info that we detached from prev trx.
 		 */
-		if (dqinfo) {
+		if (dqinfo)
 			tp->t_dqinfo = dqinfo;
-			tp->t_flags |= tflags;
-		}
 
 		if (code) {
 			xfs_buf_relse(ialloc_context);

fs/xfs/xfs_trans_dquot.c

@@ -84,13 +84,6 @@ xfs_trans_dup_dqinfo(
 
 	xfs_trans_alloc_dqinfo(ntp);
 
-	/*
-	 * Because the quota blk reservation is carried forward,
-	 * it is also necessary to carry forward the DQ_DIRTY flag.
-	 */
-	if (otp->t_flags & XFS_TRANS_DQ_DIRTY)
-		ntp->t_flags |= XFS_TRANS_DQ_DIRTY;
-
 	for (j = 0; j < XFS_QM_TRANS_DQTYPES; j++) {
 		oqa = otp->t_dqinfo->dqs[j];
 		nqa = ntp->t_dqinfo->dqs[j];
@@ -270,8 +263,6 @@ xfs_trans_mod_dquot(
 
 	if (delta)
 		trace_xfs_trans_mod_dquot_after(qtrx);
-
-	tp->t_flags |= XFS_TRANS_DQ_DIRTY;
 }
 
 
@@ -348,7 +339,7 @@ xfs_trans_apply_dquot_deltas(
 	int64_t			totalbdelta;
 	int64_t			totalrtbdelta;
 
-	if (!(tp->t_flags & XFS_TRANS_DQ_DIRTY))
+	if (!tp->t_dqinfo)
 		return;
 
 	ASSERT(tp->t_dqinfo);
@@ -490,7 +481,7 @@ xfs_trans_unreserve_and_mod_dquots(
 	struct xfs_dqtrx	*qtrx, *qa;
 	bool			locked;
 
-	if (!tp->t_dqinfo || !(tp->t_flags & XFS_TRANS_DQ_DIRTY))
+	if (!tp->t_dqinfo)
 		return;
 
 	for (j = 0; j < XFS_QM_TRANS_DQTYPES; j++) {