[PATCH 4.9 53/78] xfs: remove xfs_trans_ail_delete_bulk

From: Greg Kroah-Hartman
Date: Mon Sep 18 2017 - 05:24:38 EST


4.9-stable review patch. If anyone has any objections, please let me know.

------------------

commit 27af1bbf524459962d1477a38ac6e0b7f79aaecc upstream.

xfs_iflush_done uses an on-stack variable length array to pass the log
items to be deleted to xfs_trans_ail_delete_bulk. On-stack VLAs are a
nasty gcc extension that can lead to unbounded stack allocations, but
fortunately we can easily avoid them by simply open coding
xfs_trans_ail_delete_bulk in xfs_iflush_done, which is the only caller
of it except for the single-item xfs_trans_ail_delete.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/xfs/xfs_inode_item.c | 29 +++++++++++--------
fs/xfs/xfs_trans_ail.c | 73 +++++++++++++++++++++++-------------------------
fs/xfs/xfs_trans_priv.h | 15 +--------
3 files changed, 56 insertions(+), 61 deletions(-)

--- a/fs/xfs/xfs_inode_item.c
+++ b/fs/xfs/xfs_inode_item.c
@@ -731,22 +731,27 @@ xfs_iflush_done(
* holding the lock before removing the inode from the AIL.
*/
if (need_ail) {
- struct xfs_log_item *log_items[need_ail];
- int i = 0;
+ bool mlip_changed = false;
+
+ /* this is an opencoded batch version of xfs_trans_ail_delete */
spin_lock(&ailp->xa_lock);
for (blip = lip; blip; blip = blip->li_bio_list) {
- iip = INODE_ITEM(blip);
- if (iip->ili_logged &&
- blip->li_lsn == iip->ili_flush_lsn) {
- log_items[i++] = blip;
- }
- ASSERT(i <= need_ail);
+ if (INODE_ITEM(blip)->ili_logged &&
+ blip->li_lsn == INODE_ITEM(blip)->ili_flush_lsn)
+ mlip_changed |= xfs_ail_delete_one(ailp, blip);
}
- /* xfs_trans_ail_delete_bulk() drops the AIL lock. */
- xfs_trans_ail_delete_bulk(ailp, log_items, i,
- SHUTDOWN_CORRUPT_INCORE);
- }

+ if (mlip_changed) {
+ if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount))
+ xlog_assign_tail_lsn_locked(ailp->xa_mount);
+ if (list_empty(&ailp->xa_ail))
+ wake_up_all(&ailp->xa_empty);
+ }
+ spin_unlock(&ailp->xa_lock);
+
+ if (mlip_changed)
+ xfs_log_space_wake(ailp->xa_mount);
+ }

/*
* clean up and unlock the flush lock now we are done. We can clear the
--- a/fs/xfs/xfs_trans_ail.c
+++ b/fs/xfs/xfs_trans_ail.c
@@ -684,8 +684,23 @@ xfs_trans_ail_update_bulk(
}
}

-/*
- * xfs_trans_ail_delete_bulk - remove multiple log items from the AIL
+bool
+xfs_ail_delete_one(
+ struct xfs_ail *ailp,
+ struct xfs_log_item *lip)
+{
+ struct xfs_log_item *mlip = xfs_ail_min(ailp);
+
+ trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn);
+ xfs_ail_delete(ailp, lip);
+ lip->li_flags &= ~XFS_LI_IN_AIL;
+ lip->li_lsn = 0;
+
+ return mlip == lip;
+}
+
+/**
+ * Remove a log items from the AIL
*
* @xfs_trans_ail_delete_bulk takes an array of log items that all need to
* removed from the AIL. The caller is already holding the AIL lock, and done
@@ -706,52 +721,36 @@ xfs_trans_ail_update_bulk(
* before returning.
*/
void
-xfs_trans_ail_delete_bulk(
+xfs_trans_ail_delete(
struct xfs_ail *ailp,
- struct xfs_log_item **log_items,
- int nr_items,
+ struct xfs_log_item *lip,
int shutdown_type) __releases(ailp->xa_lock)
{
- xfs_log_item_t *mlip;
- int mlip_changed = 0;
- int i;
-
- mlip = xfs_ail_min(ailp);
-
- for (i = 0; i < nr_items; i++) {
- struct xfs_log_item *lip = log_items[i];
- if (!(lip->li_flags & XFS_LI_IN_AIL)) {
- struct xfs_mount *mp = ailp->xa_mount;
-
- spin_unlock(&ailp->xa_lock);
- if (!XFS_FORCED_SHUTDOWN(mp)) {
- xfs_alert_tag(mp, XFS_PTAG_AILDELETE,
- "%s: attempting to delete a log item that is not in the AIL",
- __func__);
- xfs_force_shutdown(mp, shutdown_type);
- }
- return;
- }
+ struct xfs_mount *mp = ailp->xa_mount;
+ bool mlip_changed;

- trace_xfs_ail_delete(lip, mlip->li_lsn, lip->li_lsn);
- xfs_ail_delete(ailp, lip);
- lip->li_flags &= ~XFS_LI_IN_AIL;
- lip->li_lsn = 0;
- if (mlip == lip)
- mlip_changed = 1;
+ if (!(lip->li_flags & XFS_LI_IN_AIL)) {
+ spin_unlock(&ailp->xa_lock);
+ if (!XFS_FORCED_SHUTDOWN(mp)) {
+ xfs_alert_tag(mp, XFS_PTAG_AILDELETE,
+ "%s: attempting to delete a log item that is not in the AIL",
+ __func__);
+ xfs_force_shutdown(mp, shutdown_type);
+ }
+ return;
}

+ mlip_changed = xfs_ail_delete_one(ailp, lip);
if (mlip_changed) {
- if (!XFS_FORCED_SHUTDOWN(ailp->xa_mount))
- xlog_assign_tail_lsn_locked(ailp->xa_mount);
+ if (!XFS_FORCED_SHUTDOWN(mp))
+ xlog_assign_tail_lsn_locked(mp);
if (list_empty(&ailp->xa_ail))
wake_up_all(&ailp->xa_empty);
- spin_unlock(&ailp->xa_lock);
+ }

+ spin_unlock(&ailp->xa_lock);
+ if (mlip_changed)
xfs_log_space_wake(ailp->xa_mount);
- } else {
- spin_unlock(&ailp->xa_lock);
- }
}

int
--- a/fs/xfs/xfs_trans_priv.h
+++ b/fs/xfs/xfs_trans_priv.h
@@ -106,18 +106,9 @@ xfs_trans_ail_update(
xfs_trans_ail_update_bulk(ailp, NULL, &lip, 1, lsn);
}

-void xfs_trans_ail_delete_bulk(struct xfs_ail *ailp,
- struct xfs_log_item **log_items, int nr_items,
- int shutdown_type)
- __releases(ailp->xa_lock);
-static inline void
-xfs_trans_ail_delete(
- struct xfs_ail *ailp,
- xfs_log_item_t *lip,
- int shutdown_type) __releases(ailp->xa_lock)
-{
- xfs_trans_ail_delete_bulk(ailp, &lip, 1, shutdown_type);
-}
+bool xfs_ail_delete_one(struct xfs_ail *ailp, struct xfs_log_item *lip);
+void xfs_trans_ail_delete(struct xfs_ail *ailp, struct xfs_log_item *lip,
+ int shutdown_type) __releases(ailp->xa_lock);

static inline void
xfs_trans_ail_remove(