[XFS] optimize XFS_IS_REALTIME_INODE w/o realtime config

Use XFS_IS_REALTIME_INODE in more places, and #define it to 0 if
CONFIG_XFS_RT is off. This should be safe because mount checks in
xfs_rtmount_init:

so if we get mounted w/o CONFIG_XFS_RT, no realtime inodes should be
encountered after that.

Defining XFS_IS_REALTIME_INODE to 0 saves a bit of stack space,
presumeably gcc can optimize around the various "if (0)" type checks:

xfs_alloc_file_space -8 xfs_bmap_adjacent -16 xfs_bmapi -8
xfs_bmap_rtalloc -16 xfs_bunmapi -28 xfs_free_file_space -64 xfs_imap +8
<-- ? hmm. xfs_iomap_write_direct -12 xfs_qm_dqusage_adjust -4
xfs_qm_vop_chown_reserve -4

SGI-PV: 971186
SGI-Modid: xfs-linux-melb:xfs-kern:30014a

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c
index 36dadc4..e051952 100644
--- a/fs/xfs/linux-2.6/xfs_aops.c
+++ b/fs/xfs/linux-2.6/xfs_aops.c
@@ -113,7 +113,7 @@
 {
 	struct xfs_mount	*mp = ip->i_mount;
 
-	if (ip->i_d.di_flags & XFS_DIFLAG_REALTIME)
+	if (XFS_IS_REALTIME_INODE(ip))
 		return mp->m_rtdev_targp->bt_bdev;
 	else
 		return mp->m_ddev_targp->bt_bdev;
diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c
index daa351a..4c82a05 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl.c
+++ b/fs/xfs/linux-2.6/xfs_ioctl.c
@@ -741,7 +741,7 @@
 	case XFS_IOC_DIOINFO: {
 		struct dioattr	da;
 		xfs_buftarg_t	*target =
-			(ip->i_d.di_flags & XFS_DIFLAG_REALTIME) ?
+			XFS_IS_REALTIME_INODE(ip) ?
 			mp->m_rtdev_targp : mp->m_ddev_targp;
 
 		da.d_mem = da.d_miniosz = 1 << target->bt_sshift;
diff --git a/fs/xfs/linux-2.6/xfs_iops.c b/fs/xfs/linux-2.6/xfs_iops.c
index 9ddef91..1ecd86a 100644
--- a/fs/xfs/linux-2.6/xfs_iops.c
+++ b/fs/xfs/linux-2.6/xfs_iops.c
@@ -612,7 +612,7 @@
 				   sysv_minor(ip->i_df.if_u2.if_rdev));
 		break;
 	default:
-		if (ip->i_d.di_flags & XFS_DIFLAG_REALTIME) {
+		if (XFS_IS_REALTIME_INODE(ip)) {
 			/*
 			 * If the file blocks are being allocated from a
 			 * realtime volume, then return the inode's realtime
diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c
index 459d364..19a1f07 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -202,7 +202,7 @@
 
 	if (unlikely(ioflags & IO_ISDIRECT)) {
 		xfs_buftarg_t	*target =
-			(ip->i_d.di_flags & XFS_DIFLAG_REALTIME) ?
+			XFS_IS_REALTIME_INODE(ip) ?
 				mp->m_rtdev_targp : mp->m_ddev_targp;
 		if ((*offset & target->bt_smask) ||
 		    (size & target->bt_smask)) {
@@ -657,7 +657,7 @@
 
 	if (ioflags & IO_ISDIRECT) {
 		xfs_buftarg_t	*target =
-			(xip->i_d.di_flags & XFS_DIFLAG_REALTIME) ?
+			XFS_IS_REALTIME_INODE(xip) ?
 				mp->m_rtdev_targp : mp->m_ddev_targp;
 
 		if ((pos & target->bt_smask) || (count & target->bt_smask)) {
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index b02452b..aca51e7 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -2969,7 +2969,7 @@
 xfs_bmap_alloc(
 	xfs_bmalloca_t	*ap)		/* bmap alloc argument struct */
 {
-	if ((ap->ip->i_d.di_flags & XFS_DIFLAG_REALTIME) && ap->userdata)
+	if (XFS_IS_REALTIME_INODE(ap->ip) && ap->userdata)
 		return xfs_bmap_rtalloc(ap);
 	return xfs_bmap_btalloc(ap);
 }
@@ -3096,8 +3096,7 @@
 		/*
 		 * Realtime allocation.  Free it and record di_nblocks update.
 		 */
-		if (whichfork == XFS_DATA_FORK &&
-		    (ip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
+		if (whichfork == XFS_DATA_FORK && XFS_IS_REALTIME_INODE(ip)) {
 			xfs_fsblock_t	bno;
 			xfs_filblks_t	len;
 
diff --git a/fs/xfs/xfs_bmap_btree.c b/fs/xfs/xfs_bmap_btree.c
index 32b49ec..c4181d8 100644
--- a/fs/xfs/xfs_bmap_btree.c
+++ b/fs/xfs/xfs_bmap_btree.c
@@ -2062,8 +2062,7 @@
 				pcur->bc_private.b.allocated;
 			pcur->bc_private.b.allocated = 0;
 			ASSERT((cur->bc_private.b.firstblock != NULLFSBLOCK) ||
-			       (cur->bc_private.b.ip->i_d.di_flags &
-				XFS_DIFLAG_REALTIME));
+			       XFS_IS_REALTIME_INODE(cur->bc_private.b.ip));
 			cur->bc_private.b.firstblock =
 				pcur->bc_private.b.firstblock;
 			ASSERT(cur->bc_private.b.flist ==
diff --git a/fs/xfs/xfs_dfrag.c b/fs/xfs/xfs_dfrag.c
index 4ad29cb..03a42d2 100644
--- a/fs/xfs/xfs_dfrag.c
+++ b/fs/xfs/xfs_dfrag.c
@@ -185,8 +185,7 @@
 	}
 
 	/* Verify both files are either real-time or non-realtime */
-	if ((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) !=
-	    (tip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
+	if (XFS_IS_REALTIME_INODE(ip) != XFS_IS_REALTIME_INODE(tip)) {
 		error = XFS_ERROR(EINVAL);
 		goto error0;
 	}
diff --git a/fs/xfs/xfs_dinode.h b/fs/xfs/xfs_dinode.h
index dedd7135..85030cb 100644
--- a/fs/xfs/xfs_dinode.h
+++ b/fs/xfs/xfs_dinode.h
@@ -273,6 +273,12 @@
 #define XFS_DIFLAG_NODEFRAG      (1 << XFS_DIFLAG_NODEFRAG_BIT)
 #define XFS_DIFLAG_FILESTREAM    (1 << XFS_DIFLAG_FILESTREAM_BIT)
 
+#ifdef CONFIG_XFS_RT
+#define XFS_IS_REALTIME_INODE(ip) ((ip)->i_d.di_flags & XFS_DIFLAG_REALTIME)
+#else
+#define XFS_IS_REALTIME_INODE(ip) (0)
+#endif
+
 #define XFS_DIFLAG_ANY \
 	(XFS_DIFLAG_REALTIME | XFS_DIFLAG_PREALLOC | XFS_DIFLAG_NEWRTBM | \
 	 XFS_DIFLAG_IMMUTABLE | XFS_DIFLAG_APPEND | XFS_DIFLAG_SYNC | \
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 805cab7..815ae97 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -1296,7 +1296,10 @@
 	if ((ip->i_d.di_mode & S_IFMT) != S_IFREG)
 		return;
 
-	if (ip->i_d.di_flags & (XFS_DIFLAG_REALTIME | XFS_DIFLAG_EXTSIZE))
+	if (XFS_IS_REALTIME_INODE(ip))
+		return;
+
+	if (ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE)
 		return;
 
 	nimaps = 2;
diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
index 637a244..fde37f8 100644
--- a/fs/xfs/xfs_iomap.c
+++ b/fs/xfs/xfs_iomap.c
@@ -141,7 +141,7 @@
 		iomapp->iomap_bsize = XFS_FSB_TO_B(mp, imap->br_blockcount);
 		iomapp->iomap_flags = flags;
 
-		if (ip->i_d.di_flags & XFS_DIFLAG_REALTIME) {
+		if (XFS_IS_REALTIME_INODE(ip)) {
 			iomapp->iomap_flags |= IOMAP_REALTIME;
 			iomapp->iomap_target = mp->m_rtdev_targp;
 		} else {
@@ -298,7 +298,7 @@
 	xfs_extlen_t	align;
 	int		eof, error;
 
-	if (ip->i_d.di_flags & XFS_DIFLAG_REALTIME)
+	if (XFS_IS_REALTIME_INODE(ip))
 		;
 	/*
 	 * If mounted with the "-o swalloc" option, roundup the allocation
@@ -524,7 +524,7 @@
 	}
 
 	if (unlikely(!imap.br_startblock &&
-		     !(ip->i_d.di_flags & XFS_DIFLAG_REALTIME))) {
+		     !(XFS_IS_REALTIME_INODE(ip)))) {
 		error = xfs_cmn_err_fsblock_zero(ip, &imap);
 		goto error_out;
 	}
@@ -687,7 +687,7 @@
 	}
 
 	if (unlikely(!imap[0].br_startblock &&
-		     !(ip->i_d.di_flags & XFS_DIFLAG_REALTIME)))
+		     !(XFS_IS_REALTIME_INODE(ip))))
 		return xfs_cmn_err_fsblock_zero(ip, &imap[0]);
 
 	*ret_imap = imap[0];
@@ -932,7 +932,7 @@
 			return XFS_ERROR(error);
 
 		if (unlikely(!imap.br_startblock &&
-			     !(ip->i_d.di_flags & XFS_DIFLAG_REALTIME)))
+			     !(XFS_IS_REALTIME_INODE(ip))))
 			return xfs_cmn_err_fsblock_zero(ip, &imap);
 
 		if ((numblks_fsb = imap.br_blockcount) == 0) {
diff --git a/fs/xfs/xfs_rtalloc.h b/fs/xfs/xfs_rtalloc.h
index 799c1f8..8d8dcd2 100644
--- a/fs/xfs/xfs_rtalloc.h
+++ b/fs/xfs/xfs_rtalloc.h
@@ -21,8 +21,6 @@
 struct xfs_mount;
 struct xfs_trans;
 
-#define XFS_IS_REALTIME_INODE(ip) ((ip)->i_d.di_flags & XFS_DIFLAG_REALTIME)
-
 /* Min and max rt extent sizes, specified in bytes */
 #define	XFS_MAX_RTEXTSIZE	(1024 * 1024 * 1024)	/* 1GB */
 #define	XFS_DFL_RTEXTSIZE	(64 * 1024)	        /* 64KB */
diff --git a/fs/xfs/xfs_rw.h b/fs/xfs/xfs_rw.h
index bcfe07a..f87db53 100644
--- a/fs/xfs/xfs_rw.h
+++ b/fs/xfs/xfs_rw.h
@@ -32,7 +32,7 @@
 static inline xfs_daddr_t
 xfs_fsb_to_db(struct xfs_inode *ip, xfs_fsblock_t fsb)
 {
-	return (((ip)->i_d.di_flags & XFS_DIFLAG_REALTIME) ? \
+	return (XFS_IS_REALTIME_INODE(ip) ? \
 		 (xfs_daddr_t)XFS_FSB_TO_BB((ip)->i_mount, (fsb)) : \
 		 XFS_FSB_TO_DADDR((ip)->i_mount, (fsb)));
 }
@@ -53,7 +53,7 @@
 {
 	xfs_extlen_t	extsz;
 
-	if (unlikely(ip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
+	if (unlikely(XFS_IS_REALTIME_INODE(ip))) {
 		extsz = (ip->i_d.di_flags & XFS_DIFLAG_EXTSIZE)
 				? ip->i_d.di_extsize
 				: ip->i_mount->m_sb.sb_rextsize;
diff --git a/fs/xfs/xfs_vnodeops.c b/fs/xfs/xfs_vnodeops.c
index d964e21..5322d9f 100644
--- a/fs/xfs/xfs_vnodeops.c
+++ b/fs/xfs/xfs_vnodeops.c
@@ -136,7 +136,7 @@
 	default:
 		vap->va_rdev = 0;
 
-		if (!(ip->i_d.di_flags & XFS_DIFLAG_REALTIME)) {
+		if (!(XFS_IS_REALTIME_INODE(ip))) {
 			vap->va_blocksize = xfs_preferred_iosize(mp);
 		} else {
 
@@ -508,7 +508,7 @@
 		 */
 		if ((ip->i_d.di_nextents || ip->i_delayed_blks) &&
 		    (mask & XFS_AT_XFLAGS) &&
-		    (ip->i_d.di_flags & XFS_DIFLAG_REALTIME) !=
+		    (XFS_IS_REALTIME_INODE(ip)) !=
 		    (vap->va_xflags & XFS_XFLAG_REALTIME)) {
 			code = XFS_ERROR(EINVAL);	/* EFBIG? */
 			goto error_return;
@@ -520,7 +520,7 @@
 		if ((mask & XFS_AT_EXTSIZE) && vap->va_extsize != 0) {
 			xfs_extlen_t	size;
 
-			if ((ip->i_d.di_flags & XFS_DIFLAG_REALTIME) ||
+			if (XFS_IS_REALTIME_INODE(ip) ||
 			    ((mask & XFS_AT_XFLAGS) &&
 			    (vap->va_xflags & XFS_XFLAG_REALTIME))) {
 				size = mp->m_sb.sb_rextsize <<
@@ -1144,7 +1144,7 @@
 		 * If this inode is on the RT dev we need to flush that
 		 * cache as well.
 		 */
-		if (ip->i_d.di_flags & XFS_DIFLAG_REALTIME)
+		if (XFS_IS_REALTIME_INODE(ip))
 			xfs_blkdev_issue_flush(ip->i_mount->m_rtdev_targp);
 	}
 
@@ -4044,7 +4044,7 @@
 	int			error = 0;
 
 	bp = xfs_buf_get_noaddr(mp->m_sb.sb_blocksize,
-				ip->i_d.di_flags & XFS_DIFLAG_REALTIME ?
+				XFS_IS_REALTIME_INODE(ip) ?
 				mp->m_rtdev_targp : mp->m_ddev_targp);
 
 	for (offset = startoff; offset <= endoff; offset = lastoffset + 1) {
@@ -4141,7 +4141,7 @@
 	error = 0;
 	if (len <= 0)	/* if nothing being freed */
 		return error;
-	rt = (ip->i_d.di_flags & XFS_DIFLAG_REALTIME);
+	rt = XFS_IS_REALTIME_INODE(ip);
 	startoffset_fsb	= XFS_B_TO_FSB(mp, offset);
 	end_dmi_offset = offset + len;
 	endoffset_fsb = XFS_B_TO_FSBT(mp, end_dmi_offset);