xfs: switch perag iteration from the for_each macros to a while based iterator

Christoph Hellwig · Darrick J. Wong · commit 86437e6abbd2 · 2024-11-05T13:38:28.000-08:00
The current for_each_perag* macros are a bit annoying in that they
require the caller to both provide an object and an index iterator, and
also somewhat obsfucate the underlying control flow mechanism.

Switch to open coded while loops using new xfs_perag_next{,_from,_range}
helpers that return the next pag structure to iterate on based on the
previous one or NULL for the loop start.

Signed-off-by: Christoph Hellwig &lt;hch@lst.de&gt;
Reviewed-by: Darrick J. Wong &lt;djwong@kernel.org&gt;
Signed-off-by: Darrick J. Wong &lt;djwong@kernel.org&gt;
diff --git a/fs/xfs/libxfs/xfs_ag.h b/fs/xfs/libxfs/xfs_ag.h
@@ -208,6 +208,34 @@ xfs_perag_rele(
 	xfs_group_rele(pag_group(pag));
 }
 
+static inline struct xfs_perag *
+xfs_perag_next_range(
+	struct xfs_mount	*mp,
+	struct xfs_perag	*pag,
+	xfs_agnumber_t		start_agno,
+	xfs_agnumber_t		end_agno)
+{
+	return to_perag(xfs_group_next_range(mp, pag ? pag_group(pag) : NULL,
+			start_agno, end_agno, XG_TYPE_AG));
+}
+
+static inline struct xfs_perag *
+xfs_perag_next_from(
+	struct xfs_mount	*mp,
+	struct xfs_perag	*pag,
+	xfs_agnumber_t		start_agno)
+{
+	return xfs_perag_next_range(mp, pag, start_agno, mp->m_sb.sb_agcount - 1);
+}
+
+static inline struct xfs_perag *
+xfs_perag_next(
+	struct xfs_mount	*mp,
+	struct xfs_perag	*pag)
+{
+	return xfs_perag_next_from(mp, pag, 0);
+}
+
 /*
  * Per-ag geometry infomation and validation
  */
@@ -273,40 +301,6 @@ xfs_ag_contains_log(struct xfs_mount *mp, xfs_agnumber_t agno)
 	       agno == XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart);
 }
 
-/*
- * Perag iteration APIs
- */
-static inline struct xfs_perag *
-xfs_perag_next(
-	struct xfs_perag	*pag,
-	xfs_agnumber_t		*agno,
-	xfs_agnumber_t		end_agno)
-{
-	struct xfs_mount	*mp = pag_mount(pag);
-
-	*agno = pag_agno(pag) + 1;
-	xfs_perag_rele(pag);
-	while (*agno <= end_agno) {
-		pag = xfs_perag_grab(mp, *agno);
-		if (pag)
-			return pag;
-		(*agno)++;
-	}
-	return NULL;
-}
-
-#define for_each_perag_range(mp, agno, end_agno, pag) \
-	for ((pag) = xfs_perag_grab((mp), (agno)); \
-		(pag) != NULL; \
-		(pag) = xfs_perag_next((pag), &(agno), (end_agno)))
-
-#define for_each_perag_from(mp, agno, pag) \
-	for_each_perag_range((mp), (agno), (mp)->m_sb.sb_agcount - 1, (pag))
-
-#define for_each_perag(mp, agno, pag) \
-	(agno) = 0; \
-	for_each_perag_from((mp), (agno), (pag))
-
 static inline struct xfs_perag *
 xfs_perag_next_wrap(
 	struct xfs_perag	*pag,
diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
@@ -1109,14 +1109,13 @@ int
 xfs_update_secondary_sbs(
 	struct xfs_mount	*mp)
 {
-	struct xfs_perag	*pag;
-	xfs_agnumber_t		agno = 1;
+	struct xfs_perag	*pag = NULL;
 	int			saved_error = 0;
 	int			error = 0;
 	LIST_HEAD		(buffer_list);
 
 	/* update secondary superblocks. */
-	for_each_perag_from(mp, agno, pag) {
+	while ((pag = xfs_perag_next_from(mp, pag, 1))) {
 		struct xfs_buf		*bp;
 
 		error = xfs_buf_get(mp->m_ddev_targp,
@@ -1146,7 +1145,7 @@ xfs_update_secondary_sbs(
 		xfs_buf_relse(bp);
 
 		/* don't hold too many buffers at once */
-		if (agno % 16)
+		if (pag_agno(pag) % 16)
 			continue;
 
 		error = xfs_buf_delwri_submit(&buffer_list);
@@ -1160,12 +1159,8 @@ xfs_update_secondary_sbs(
 		}
 	}
 	error = xfs_buf_delwri_submit(&buffer_list);
-	if (error) {
-		xfs_warn(mp,
-		"write error %d updating a secondary superblock near ag %d",
-			error, agno);
-	}
-
+	if (error)
+		xfs_warn(mp, "error %d writing secondary superblocks", error);
 	return saved_error ? saved_error : error;
 }
 
diff --git a/fs/xfs/libxfs/xfs_types.c b/fs/xfs/libxfs/xfs_types.c
@@ -170,13 +170,12 @@ xfs_icount_range(
 	unsigned long long	*max)
 {
 	unsigned long long	nr_inos = 0;
-	struct xfs_perag	*pag;
-	xfs_agnumber_t		agno;
+	struct xfs_perag	*pag = NULL;
 
 	/* root, rtbitmap, rtsum all live in the first chunk */
 	*min = XFS_INODES_PER_CHUNK;
 
-	for_each_perag(mp, agno, pag)
+	while ((pag = xfs_perag_next(mp, pag)))
 		nr_inos += pag->agino_max - pag->agino_min + 1;
 	*max = nr_inos;
 }
diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c
@@ -760,11 +760,10 @@ xchk_bmap_check_rmaps(
 	struct xfs_scrub	*sc,
 	int			whichfork)
 {
-	struct xfs_perag	*pag;
-	xfs_agnumber_t		agno;
+	struct xfs_perag	*pag = NULL;
 	int			error;
 
-	for_each_perag(sc->mp, agno, pag) {
+	while ((pag = xfs_perag_next(sc->mp, pag))) {
 		error = xchk_bmap_check_ag_rmaps(sc, whichfork, pag);
 		if (error ||
 		    (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) {
diff --git a/fs/xfs/scrub/bmap_repair.c b/fs/xfs/scrub/bmap_repair.c
@@ -407,12 +407,11 @@ xrep_bmap_find_mappings(
 	struct xrep_bmap	*rb)
 {
 	struct xfs_scrub	*sc = rb->sc;
-	struct xfs_perag	*pag;
-	xfs_agnumber_t		agno;
+	struct xfs_perag	*pag = NULL;
 	int			error = 0;
 
 	/* Iterate the rmaps for extents. */
-	for_each_perag(sc->mp, agno, pag) {
+	while ((pag = xfs_perag_next(sc->mp, pag))) {
 		error = xrep_bmap_scan_ag(rb, pag);
 		if (error) {
 			xfs_perag_rele(pag);
diff --git a/fs/xfs/scrub/fscounters.c b/fs/xfs/scrub/fscounters.c
@@ -74,10 +74,9 @@ xchk_fscount_warmup(
 	struct xfs_buf		*agi_bp = NULL;
 	struct xfs_buf		*agf_bp = NULL;
 	struct xfs_perag	*pag = NULL;
-	xfs_agnumber_t		agno;
 	int			error = 0;
 
-	for_each_perag(mp, agno, pag) {
+	while ((pag = xfs_perag_next(mp, pag))) {
 		if (xchk_should_terminate(sc, &error))
 			break;
 		if (xfs_perag_initialised_agi(pag) &&
@@ -295,9 +294,8 @@ xchk_fscount_aggregate_agcounts(
 	struct xchk_fscounters	*fsc)
 {
 	struct xfs_mount	*mp = sc->mp;
-	struct xfs_perag	*pag;
+	struct xfs_perag	*pag = NULL;
 	uint64_t		delayed;
-	xfs_agnumber_t		agno;
 	int			tries = 8;
 	int			error = 0;
 
@@ -306,7 +304,7 @@ xchk_fscount_aggregate_agcounts(
 	fsc->ifree = 0;
 	fsc->fdblocks = 0;
 
-	for_each_perag(mp, agno, pag) {
+	while ((pag = xfs_perag_next(mp, pag))) {
 		if (xchk_should_terminate(sc, &error))
 			break;
 
@@ -327,7 +325,7 @@ xchk_fscount_aggregate_agcounts(
 		if (xfs_has_lazysbcount(sc->mp)) {
 			fsc->fdblocks += pag->pagf_btreeblks;
 		} else {
-			error = xchk_fscount_btreeblks(sc, fsc, agno);
+			error = xchk_fscount_btreeblks(sc, fsc, pag_agno(pag));
 			if (error)
 				break;
 		}
diff --git a/fs/xfs/scrub/health.c b/fs/xfs/scrub/health.c
@@ -160,12 +160,11 @@ STATIC void
 xchk_mark_all_healthy(
 	struct xfs_mount	*mp)
 {
-	struct xfs_perag	*pag;
-	xfs_agnumber_t		agno;
+	struct xfs_perag	*pag = NULL;
 
 	xfs_fs_mark_healthy(mp, XFS_SICK_FS_INDIRECT);
 	xfs_rt_mark_healthy(mp, XFS_SICK_RT_INDIRECT);
-	for_each_perag(mp, agno, pag)
+	while ((pag = xfs_perag_next(mp, pag)))
 		xfs_ag_mark_healthy(pag, XFS_SICK_AG_INDIRECT);
 }
 
@@ -294,9 +293,7 @@ xchk_health_record(
 	struct xfs_scrub	*sc)
 {
 	struct xfs_mount	*mp = sc->mp;
-	struct xfs_perag	*pag;
-	xfs_agnumber_t		agno;
-
+	struct xfs_perag	*pag = NULL;
 	unsigned int		sick;
 	unsigned int		checked;
 
@@ -308,7 +305,7 @@ xchk_health_record(
 	if (sick & XFS_SICK_RT_PRIMARY)
 		xchk_set_corrupt(sc);
 
-	for_each_perag(mp, agno, pag) {
+	while ((pag = xfs_perag_next(mp, pag))) {
 		xfs_ag_measure_sickness(pag, &sick, &checked);
 		if (sick & XFS_SICK_AG_PRIMARY)
 			xchk_set_corrupt(sc);
diff --git a/fs/xfs/scrub/inode_repair.c b/fs/xfs/scrub/inode_repair.c
@@ -761,14 +761,13 @@ STATIC int
 xrep_dinode_count_rmaps(
 	struct xrep_inode	*ri)
 {
-	struct xfs_perag	*pag;
-	xfs_agnumber_t		agno;
+	struct xfs_perag	*pag = NULL;
 	int			error;
 
 	if (!xfs_has_rmapbt(ri->sc->mp) || xfs_has_realtime(ri->sc->mp))
 		return -EOPNOTSUPP;
 
-	for_each_perag(ri->sc->mp, agno, pag) {
+	while ((pag = xfs_perag_next(ri->sc->mp, pag))) {
 		error = xrep_dinode_count_ag_rmaps(ri, pag);
 		if (error) {
 			xfs_perag_rele(pag);
diff --git a/fs/xfs/xfs_discard.c b/fs/xfs/xfs_discard.c
@@ -387,8 +387,8 @@ xfs_trim_datadev_extents(
 {
 	xfs_agnumber_t		start_agno, end_agno;
 	xfs_agblock_t		start_agbno, end_agbno;
+	struct xfs_perag	*pag = NULL;
 	xfs_daddr_t		ddev_end;
-	struct xfs_perag	*pag;
 	int			last_error = 0, error;
 
 	ddev_end = min_t(xfs_daddr_t, end,
@@ -399,10 +399,10 @@ xfs_trim_datadev_extents(
 	end_agno = xfs_daddr_to_agno(mp, ddev_end);
 	end_agbno = xfs_daddr_to_agbno(mp, ddev_end);
 
-	for_each_perag_range(mp, start_agno, end_agno, pag) {
+	while ((pag = xfs_perag_next_range(mp, pag, start_agno, end_agno))) {
 		xfs_agblock_t	agend = pag->block_count;
 
-		if (start_agno == end_agno)
+		if (pag_agno(pag) == end_agno)
 			agend = end_agbno;
 		error = xfs_trim_perag_extents(pag, start_agbno, agend, minlen);
 		if (error)
diff --git a/fs/xfs/xfs_extent_busy.c b/fs/xfs/xfs_extent_busy.c
@@ -629,11 +629,10 @@ void
 xfs_extent_busy_wait_all(
 	struct xfs_mount	*mp)
 {
-	struct xfs_perag	*pag;
+	struct xfs_perag	*pag = NULL;
 	DEFINE_WAIT		(wait);
-	xfs_agnumber_t		agno;
 
-	for_each_perag(mp, agno, pag) {
+	while ((pag = xfs_perag_next(mp, pag))) {
 		do {
 			prepare_to_wait(&pag->pagb_wait, &wait, TASK_KILLABLE);
 			if  (RB_EMPTY_ROOT(&pag->pagb_tree))
diff --git a/fs/xfs/xfs_fsmap.c b/fs/xfs/xfs_fsmap.c
@@ -460,11 +460,11 @@ __xfs_getfsmap_datadev(
 	void				*priv)
 {
 	struct xfs_mount		*mp = tp->t_mountp;
-	struct xfs_perag		*pag;
+	struct xfs_perag		*pag = NULL;
 	struct xfs_btree_cur		*bt_cur = NULL;
 	xfs_fsblock_t			start_fsb;
 	xfs_fsblock_t			end_fsb;
-	xfs_agnumber_t			start_ag, end_ag, ag;
+	xfs_agnumber_t			start_ag, end_ag;
 	uint64_t			eofs;
 	int				error = 0;
 
@@ -512,8 +512,7 @@ __xfs_getfsmap_datadev(
 	start_ag = XFS_FSB_TO_AGNO(mp, start_fsb);
 	end_ag = XFS_FSB_TO_AGNO(mp, end_fsb);
 
-	ag = start_ag;
-	for_each_perag_range(mp, ag, end_ag, pag) {
+	while ((pag = xfs_perag_next_range(mp, pag, start_ag, end_ag))) {
 		/*
 		 * Set the AG high key from the fsmap high key if this
 		 * is the last AG that we're querying.
diff --git a/fs/xfs/xfs_fsops.c b/fs/xfs/xfs_fsops.c
@@ -528,13 +528,12 @@ int
 xfs_fs_reserve_ag_blocks(
 	struct xfs_mount	*mp)
 {
-	xfs_agnumber_t		agno;
-	struct xfs_perag	*pag;
+	struct xfs_perag	*pag = NULL;
 	int			error = 0;
 	int			err2;
 
 	mp->m_finobt_nores = false;
-	for_each_perag(mp, agno, pag) {
+	while ((pag = xfs_perag_next(mp, pag))) {
 		err2 = xfs_ag_resv_init(pag, NULL);
 		if (err2 && !error)
 			error = err2;
@@ -556,9 +555,8 @@ void
 xfs_fs_unreserve_ag_blocks(
 	struct xfs_mount	*mp)
 {
-	xfs_agnumber_t		agno;
-	struct xfs_perag	*pag;
+	struct xfs_perag	*pag = NULL;
 
-	for_each_perag(mp, agno, pag)
+	while ((pag = xfs_perag_next(mp, pag)))
 		xfs_ag_resv_free(pag);
 }
diff --git a/fs/xfs/xfs_health.c b/fs/xfs/xfs_health.c
@@ -28,8 +28,7 @@ void
 xfs_health_unmount(
 	struct xfs_mount	*mp)
 {
-	struct xfs_perag	*pag;
-	xfs_agnumber_t		agno;
+	struct xfs_perag	*pag = NULL;
 	unsigned int		sick = 0;
 	unsigned int		checked = 0;
 	bool			warn = false;
@@ -38,7 +37,7 @@ xfs_health_unmount(
 		return;
 
 	/* Measure AG corruption levels. */
-	for_each_perag(mp, agno, pag) {
+	while ((pag = xfs_perag_next(mp, pag))) {
 		xfs_ag_measure_sickness(pag, &sick, &checked);
 		if (sick) {
 			trace_xfs_ag_unfixed_corruption(pag, sick);
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
@@ -1383,13 +1383,12 @@ void
 xfs_blockgc_stop(
 	struct xfs_mount	*mp)
 {
-	struct xfs_perag	*pag;
-	xfs_agnumber_t		agno;
+	struct xfs_perag	*pag = NULL;
 
 	if (!xfs_clear_blockgc_enabled(mp))
 		return;
 
-	for_each_perag(mp, agno, pag)
+	while ((pag = xfs_perag_next(mp, pag)))
 		cancel_delayed_work_sync(&pag->pag_blockgc_work);
 	trace_xfs_blockgc_stop(mp, __return_address);
 }
diff --git a/fs/xfs/xfs_iwalk.c b/fs/xfs/xfs_iwalk.c
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c

Original file line number	Diff line number	Diff line change
`@@ -170,13 +170,12 @@ xfs_icount_range(`
`170`	`170`	`unsigned long long *max)`
`171`	`171`	`{`
`172`	`172`	`unsigned long long nr_inos = 0;`
`173`		`- struct xfs_perag *pag;`
`174`		`- xfs_agnumber_t agno;`
	`173`	`+ struct xfs_perag *pag = NULL;`
`175`	`174`
`176`	`175`	`/* root, rtbitmap, rtsum all live in the first chunk */`
`177`	`176`	`*min = XFS_INODES_PER_CHUNK;`
`178`	`177`
`179`		`- for_each_perag(mp, agno, pag)`
	`178`	`+ while ((pag = xfs_perag_next(mp, pag)))`
`180`	`179`	`nr_inos += pag->agino_max - pag->agino_min + 1;`
`181`	`180`	`*max = nr_inos;`
`182`	`181`	`}`