xfs: remove xfs_trans_ail_delete_bulk

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@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

3 files changed, 55 insertions, 60 deletions

diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c
index d90e7811ccdd..08cb7d1a4a3a 100644
--- 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
diff --git a/fs/xfs/xfs_trans_ail.c b/fs/xfs/xfs_trans_ail.c
index d6c9c3e9e02b..9056c0f34a3c 100644
--- 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;
+        struct xfs_mount        *mp = ailp->xa_mount;
+        bool                    mlip_changed;
 
-        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;
+        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);
                 }
-
-                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;
+                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
diff --git a/fs/xfs/xfs_trans_priv.h b/fs/xfs/xfs_trans_priv.h
index 49931b72da8a..d91706c56c63 100644
--- 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(