diff --git a/fs/xfs/scrub/common.c b/fs/xfs/scrub/common.c
index 8558ca05e11d..06b697f72f23 100644
--- a/fs/xfs/scrub/common.c
+++ b/fs/xfs/scrub/common.c
@@ -884,6 +884,7 @@ xchk_stop_reaping(
 {
 	sc->flags |= XCHK_REAPING_DISABLED;
 	xfs_blockgc_stop(sc->mp);
+	xfs_inodegc_stop(sc->mp);
 }
 
 /* Restart background reaping of resources. */
@@ -891,6 +892,12 @@ void
 xchk_start_reaping(
 	struct xfs_scrub	*sc)
 {
+	/*
+	 * Readonly filesystems do not perform inactivation, so there's no
+	 * need to restart the worker.
+	 */
+	if (!(sc->mp->m_flags & XFS_MOUNT_RDONLY))
+		xfs_inodegc_start(sc->mp);
 	xfs_blockgc_start(sc->mp);
 	sc->flags &= ~XCHK_REAPING_DISABLED;
 }
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index b9214733d0c3..fedfa40e3cd6 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -213,7 +213,7 @@ xfs_blockgc_queue(
 {
 	rcu_read_lock();
 	if (radix_tree_tagged(&pag->pag_ici_root, XFS_ICI_BLOCKGC_TAG))
-		queue_delayed_work(pag->pag_mount->m_gc_workqueue,
+		queue_delayed_work(pag->pag_mount->m_blockgc_wq,
 				   &pag->pag_blockgc_work,
 				   msecs_to_jiffies(xfs_blockgc_secs * 1000));
 	rcu_read_unlock();
@@ -450,6 +450,21 @@ xfs_iget_check_free_state(
 	return 0;
 }
 
+/* Make all pending inactivation work start immediately. */
+static void
+xfs_inodegc_queue_all(
+	struct xfs_mount	*mp)
+{
+	struct xfs_inodegc	*gc;
+	int			cpu;
+
+	for_each_online_cpu(cpu) {
+		gc = per_cpu_ptr(mp->m_inodegc, cpu);
+		if (!llist_empty(&gc->list))
+			queue_work_on(cpu, mp->m_inodegc_wq, &gc->work);
+	}
+}
+
 /*
  * Check the validity of the inode we just found it the cache
  */
@@ -482,13 +497,30 @@ xfs_iget_cache_hit(
 	 * reclaimable state, wait for the initialisation to complete
 	 * before continuing.
 	 *
+	 * If we're racing with the inactivation worker we also want to wait.
+	 * If we're creating a new file, it's possible that the worker
+	 * previously marked the inode as free on disk but hasn't finished
+	 * updating the incore state yet.  The AGI buffer will be dirty and
+	 * locked to the icreate transaction, so a synchronous push of the
+	 * inodegc workers would result in deadlock.  For a regular iget, the
+	 * worker is running already, so we might as well wait.
+	 *
 	 * XXX(hch): eventually we should do something equivalent to
 	 *	     wait_on_inode to wait for these flags to be cleared
 	 *	     instead of polling for it.
 	 */
-	if (ip->i_flags & (XFS_INEW | XFS_IRECLAIM))
+	if (ip->i_flags & (XFS_INEW | XFS_IRECLAIM | XFS_INACTIVATING))
 		goto out_skip;
 
+	if (ip->i_flags & XFS_NEED_INACTIVE) {
+		/* Unlinked inodes cannot be re-grabbed. */
+		if (VFS_I(ip)->i_nlink == 0) {
+			error = -ENOENT;
+			goto out_error;
+		}
+		goto out_inodegc_flush;
+	}
+
 	/*
 	 * Check the inode free state is valid. This also detects lookup
 	 * racing with unlinks.
@@ -536,6 +568,17 @@ xfs_iget_cache_hit(
 	spin_unlock(&ip->i_flags_lock);
 	rcu_read_unlock();
 	return error;
+
+out_inodegc_flush:
+	spin_unlock(&ip->i_flags_lock);
+	rcu_read_unlock();
+	/*
+	 * Do not wait for the workers, because the caller could hold an AGI
+	 * buffer lock.  We're just going to sleep in a loop anyway.
+	 */
+	if (xfs_is_inodegc_enabled(mp))
+		xfs_inodegc_queue_all(mp);
+	return -EAGAIN;
 }
 
 static int
@@ -863,6 +906,7 @@ xfs_reclaim_inode(
 
 	xfs_iflags_clear(ip, XFS_IFLUSHING);
 reclaim:
+	trace_xfs_inode_reclaiming(ip);
 
 	/*
 	 * Because we use RCU freeing we need to ensure the inode always appears
@@ -1340,6 +1384,8 @@ xfs_blockgc_start(
 
 /* Don't try to run block gc on an inode that's in any of these states. */
 #define XFS_BLOCKGC_NOGRAB_IFLAGS	(XFS_INEW | \
+					 XFS_NEED_INACTIVE | \
+					 XFS_INACTIVATING | \
 					 XFS_IRECLAIMABLE | \
 					 XFS_IRECLAIM)
 /*
@@ -1741,25 +1787,13 @@ xfs_check_delalloc(
 #define xfs_check_delalloc(ip, whichfork)	do { } while (0)
 #endif
 
-/*
- * We set the inode flag atomically with the radix tree tag.
- * Once we get tag lookups on the radix tree, this inode flag
- * can go away.
- */
-void
-xfs_inode_mark_reclaimable(
+/* Schedule the inode for reclaim. */
+static void
+xfs_inodegc_set_reclaimable(
 	struct xfs_inode	*ip)
 {
 	struct xfs_mount	*mp = ip->i_mount;
 	struct xfs_perag	*pag;
-	bool			need_inactive = xfs_inode_needs_inactive(ip);
-
-	if (!need_inactive) {
-		/* Going straight to reclaim, so drop the dquots. */
-		xfs_qm_dqdetach(ip);
-	} else {
-		xfs_inactive(ip);
-	}
 
 	if (!XFS_FORCED_SHUTDOWN(mp) && ip->i_delayed_blks) {
 		xfs_check_delalloc(ip, XFS_DATA_FORK);
@@ -1767,30 +1801,276 @@ xfs_inode_mark_reclaimable(
 		ASSERT(0);
 	}
 
+	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
+	spin_lock(&pag->pag_ici_lock);
+	spin_lock(&ip->i_flags_lock);
+
+	trace_xfs_inode_set_reclaimable(ip);
+	ip->i_flags &= ~(XFS_NEED_INACTIVE | XFS_INACTIVATING);
+	ip->i_flags |= XFS_IRECLAIMABLE;
+	xfs_perag_set_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
+			XFS_ICI_RECLAIM_TAG);
+
+	spin_unlock(&ip->i_flags_lock);
+	spin_unlock(&pag->pag_ici_lock);
+	xfs_perag_put(pag);
+}
+
+/*
+ * Free all speculative preallocations and possibly even the inode itself.
+ * This is the last chance to make changes to an otherwise unreferenced file
+ * before incore reclamation happens.
+ */
+static void
+xfs_inodegc_inactivate(
+	struct xfs_inode	*ip)
+{
+	struct xfs_mount        *mp = ip->i_mount;
+
+	/*
+	* Inactivation isn't supposed to run when the fs is frozen because
+	* we don't want kernel threads to block on transaction allocation.
+	*/
+	ASSERT(mp->m_super->s_writers.frozen < SB_FREEZE_FS);
+
+	trace_xfs_inode_inactivating(ip);
+	xfs_inactive(ip);
+	xfs_inodegc_set_reclaimable(ip);
+}
+
+void
+xfs_inodegc_worker(
+	struct work_struct	*work)
+{
+	struct xfs_inodegc	*gc = container_of(work, struct xfs_inodegc,
+							work);
+	struct llist_node	*node = llist_del_all(&gc->list);
+	struct xfs_inode	*ip, *n;
+
+	WRITE_ONCE(gc->items, 0);
+
+	if (!node)
+		return;
+
+	ip = llist_entry(node, struct xfs_inode, i_gclist);
+	trace_xfs_inodegc_worker(ip->i_mount, __return_address);
+
+	llist_for_each_entry_safe(ip, n, node, i_gclist) {
+		xfs_iflags_set(ip, XFS_INACTIVATING);
+		xfs_inodegc_inactivate(ip);
+	}
+}
+
+/*
+ * Force all currently queued inode inactivation work to run immediately, and
+ * wait for the work to finish. Two pass - queue all the work first pass, wait
+ * for it in a second pass.
+ */
+void
+xfs_inodegc_flush(
+	struct xfs_mount	*mp)
+{
+	struct xfs_inodegc	*gc;
+	int			cpu;
+
+	if (!xfs_is_inodegc_enabled(mp))
+		return;
+
+	trace_xfs_inodegc_flush(mp, __return_address);
+
+	xfs_inodegc_queue_all(mp);
+
+	for_each_online_cpu(cpu) {
+		gc = per_cpu_ptr(mp->m_inodegc, cpu);
+		flush_work(&gc->work);
+	}
+}
+
+/*
+ * Flush all the pending work and then disable the inode inactivation background
+ * workers and wait for them to stop.
+ */
+void
+xfs_inodegc_stop(
+	struct xfs_mount	*mp)
+{
+	struct xfs_inodegc	*gc;
+	int			cpu;
+
+	if (!xfs_clear_inodegc_enabled(mp))
+		return;
+
+	xfs_inodegc_queue_all(mp);
+
+	for_each_online_cpu(cpu) {
+		gc = per_cpu_ptr(mp->m_inodegc, cpu);
+		cancel_work_sync(&gc->work);
+	}
+	trace_xfs_inodegc_stop(mp, __return_address);
+}
+
+/*
+ * Enable the inode inactivation background workers and schedule deferred inode
+ * inactivation work if there is any.
+ */
+void
+xfs_inodegc_start(
+	struct xfs_mount	*mp)
+{
+	if (xfs_set_inodegc_enabled(mp))
+		return;
+
+	trace_xfs_inodegc_start(mp, __return_address);
+	xfs_inodegc_queue_all(mp);
+}
+
+/*
+ * Schedule the inactivation worker when:
+ *
+ *  - We've accumulated more than one inode cluster buffer's worth of inodes.
+ */
+static inline bool
+xfs_inodegc_want_queue_work(
+	struct xfs_inode	*ip,
+	unsigned int		items)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+
+	if (items > mp->m_ino_geo.inodes_per_cluster)
+		return true;
+
+	return false;
+}
+
+/*
+ * Upper bound on the number of inodes in each AG that can be queued for
+ * inactivation at any given time, to avoid monopolizing the workqueue.
+ */
+#define XFS_INODEGC_MAX_BACKLOG		(4 * XFS_INODES_PER_CHUNK)
+
+/*
+ * Make the frontend wait for inactivations when:
+ *
+ *  - The queue depth exceeds the maximum allowable percpu backlog.
+ */
+static inline bool
+xfs_inodegc_want_flush_work(
+	struct xfs_inode	*ip,
+	unsigned int		items)
+{
+	if (items > XFS_INODEGC_MAX_BACKLOG)
+		return true;
+
+	return false;
+}
+
+/*
+ * Queue a background inactivation worker if there are inodes that need to be
+ * inactivated and higher level xfs code hasn't disabled the background
+ * workers.
+ */
+static void
+xfs_inodegc_queue(
+	struct xfs_inode	*ip)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	struct xfs_inodegc	*gc;
+	int			items;
+
+	trace_xfs_inode_set_need_inactive(ip);
+	spin_lock(&ip->i_flags_lock);
+	ip->i_flags |= XFS_NEED_INACTIVE;
+	spin_unlock(&ip->i_flags_lock);
+
+	gc = get_cpu_ptr(mp->m_inodegc);
+	llist_add(&ip->i_gclist, &gc->list);
+	items = READ_ONCE(gc->items);
+	WRITE_ONCE(gc->items, items + 1);
+	put_cpu_ptr(gc);
+
+	if (!xfs_is_inodegc_enabled(mp))
+		return;
+
+	if (xfs_inodegc_want_queue_work(ip, items)) {
+		trace_xfs_inodegc_queue(mp, __return_address);
+		queue_work(mp->m_inodegc_wq, &gc->work);
+	}
+
+	if (xfs_inodegc_want_flush_work(ip, items)) {
+		trace_xfs_inodegc_throttle(mp, __return_address);
+		flush_work(&gc->work);
+	}
+}
+
+/*
+ * Fold the dead CPU inodegc queue into the current CPUs queue.
+ */
+void
+xfs_inodegc_cpu_dead(
+	struct xfs_mount	*mp,
+	unsigned int		dead_cpu)
+{
+	struct xfs_inodegc	*dead_gc, *gc;
+	struct llist_node	*first, *last;
+	unsigned int		count = 0;
+
+	dead_gc = per_cpu_ptr(mp->m_inodegc, dead_cpu);
+	cancel_work_sync(&dead_gc->work);
+
+	if (llist_empty(&dead_gc->list))
+		return;
+
+	first = dead_gc->list.first;
+	last = first;
+	while (last->next) {
+		last = last->next;
+		count++;
+	}
+	dead_gc->list.first = NULL;
+	dead_gc->items = 0;
+
+	/* Add pending work to current CPU */
+	gc = get_cpu_ptr(mp->m_inodegc);
+	llist_add_batch(first, last, &gc->list);
+	count += READ_ONCE(gc->items);
+	WRITE_ONCE(gc->items, count);
+	put_cpu_ptr(gc);
+
+	trace_xfs_inodegc_queue(mp, __return_address);
+	queue_work(mp->m_inodegc_wq, &gc->work);
+}
+
+/*
+ * We set the inode flag atomically with the radix tree tag.  Once we get tag
+ * lookups on the radix tree, this inode flag can go away.
+ *
+ * We always use background reclaim here because even if the inode is clean, it
+ * still may be under IO and hence we have wait for IO completion to occur
+ * before we can reclaim the inode. The background reclaim path handles this
+ * more efficiently than we can here, so simply let background reclaim tear down
+ * all inodes.
+ */
+void
+xfs_inode_mark_reclaimable(
+	struct xfs_inode	*ip)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	bool			need_inactive;
+
 	XFS_STATS_INC(mp, vn_reclaim);
 
 	/*
-	 * We should never get here with one of the reclaim flags already set.
+	 * We should never get here with any of the reclaim flags already set.
 	 */
-	ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_IRECLAIMABLE));
-	ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_IRECLAIM));
+	ASSERT_ALWAYS(!xfs_iflags_test(ip, XFS_ALL_IRECLAIM_FLAGS));
 
-	/*
-	 * We always use background reclaim here because even if the inode is
-	 * clean, it still may be under IO and hence we have wait for IO
-	 * completion to occur before we can reclaim the inode. The background
-	 * reclaim path handles this more efficiently than we can here, so
-	 * simply let background reclaim tear down all inodes.
-	 */
-	pag = xfs_perag_get(mp, XFS_INO_TO_AGNO(mp, ip->i_ino));
-	spin_lock(&pag->pag_ici_lock);
-	spin_lock(&ip->i_flags_lock);
-
-	xfs_perag_set_inode_tag(pag, XFS_INO_TO_AGINO(mp, ip->i_ino),
-			XFS_ICI_RECLAIM_TAG);
-	__xfs_iflags_set(ip, XFS_IRECLAIMABLE);
+	need_inactive = xfs_inode_needs_inactive(ip);
+	if (need_inactive) {
+		xfs_inodegc_queue(ip);
+		return;
+	}
 
-	spin_unlock(&ip->i_flags_lock);
-	spin_unlock(&pag->pag_ici_lock);
-	xfs_perag_put(pag);
+	/* Going straight to reclaim, so drop the dquots. */
+	xfs_qm_dqdetach(ip);
+	xfs_inodegc_set_reclaimable(ip);
 }
diff --git a/fs/xfs/xfs_icache.h b/fs/xfs/xfs_icache.h
index d0062ebb3f7a..8175148afd50 100644
--- a/fs/xfs/xfs_icache.h
+++ b/fs/xfs/xfs_icache.h
@@ -74,4 +74,10 @@ int xfs_icache_inode_is_allocated(struct xfs_mount *mp, struct xfs_trans *tp,
 void xfs_blockgc_stop(struct xfs_mount *mp);
 void xfs_blockgc_start(struct xfs_mount *mp);
 
+void xfs_inodegc_worker(struct work_struct *work);
+void xfs_inodegc_flush(struct xfs_mount *mp);
+void xfs_inodegc_stop(struct xfs_mount *mp);
+void xfs_inodegc_start(struct xfs_mount *mp);
+void xfs_inodegc_cpu_dead(struct xfs_mount *mp, unsigned int cpu);
+
 #endif
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index e3137bbc7b14..1f62b481d8c5 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -42,6 +42,7 @@ typedef struct xfs_inode {
 	mrlock_t		i_lock;		/* inode lock */
 	mrlock_t		i_mmaplock;	/* inode mmap IO lock */
 	atomic_t		i_pincount;	/* inode pin count */
+	struct llist_node	i_gclist;	/* deferred inactivation list */
 
 	/*
 	 * Bitsets of inode metadata that have been checked and/or are sick.
@@ -240,6 +241,7 @@ static inline bool xfs_inode_has_bigtime(struct xfs_inode *ip)
 #define __XFS_IPINNED_BIT	8	 /* wakeup key for zero pin count */
 #define XFS_IPINNED		(1 << __XFS_IPINNED_BIT)
 #define XFS_IEOFBLOCKS		(1 << 9) /* has the preallocblocks tag set */
+#define XFS_NEED_INACTIVE	(1 << 10) /* see XFS_INACTIVATING below */
 /*
  * If this unlinked inode is in the middle of recovery, don't let drop_inode
  * truncate and free the inode.  This can happen if we iget the inode during
@@ -248,6 +250,21 @@ static inline bool xfs_inode_has_bigtime(struct xfs_inode *ip)
 #define XFS_IRECOVERY		(1 << 11)
 #define XFS_ICOWBLOCKS		(1 << 12)/* has the cowblocks tag set */
 
+/*
+ * If we need to update on-disk metadata before this IRECLAIMABLE inode can be
+ * freed, then NEED_INACTIVE will be set.  Once we start the updates, the
+ * INACTIVATING bit will be set to keep iget away from this inode.  After the
+ * inactivation completes, both flags will be cleared and the inode is a
+ * plain old IRECLAIMABLE inode.
+ */
+#define XFS_INACTIVATING	(1 << 13)
+
+/* All inode state flags related to inode reclaim. */
+#define XFS_ALL_IRECLAIM_FLAGS	(XFS_IRECLAIMABLE | \
+				 XFS_IRECLAIM | \
+				 XFS_NEED_INACTIVE | \
+				 XFS_INACTIVATING)
+
 /*
  * Per-lifetime flags need to be reset when re-using a reclaimable inode during
  * inode lookup. This prevents unintended behaviour on the new inode from
@@ -255,7 +272,8 @@ static inline bool xfs_inode_has_bigtime(struct xfs_inode *ip)
  */
 #define XFS_IRECLAIM_RESET_FLAGS	\
 	(XFS_IRECLAIMABLE | XFS_IRECLAIM | \
-	 XFS_IDIRTY_RELEASE | XFS_ITRUNCATED)
+	 XFS_IDIRTY_RELEASE | XFS_ITRUNCATED | XFS_NEED_INACTIVE | \
+	 XFS_INACTIVATING)
 
 /*
  * Flags for inode locking.
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 1721fce2ec94..a98d2429d795 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -2786,6 +2786,13 @@ xlog_recover_process_iunlinks(
 		}
 		xfs_buf_rele(agibp);
 	}
+
+	/*
+	 * Flush the pending unlinked inodes to ensure that the inactivations
+	 * are fully completed on disk and the incore inodes can be reclaimed
+	 * before we signal that recovery is complete.
+	 */
+	xfs_inodegc_flush(mp);
 }
 
 STATIC void
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index baf7b323cb15..1f7e9a608f38 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -514,7 +514,8 @@ xfs_check_summary_counts(
  * Flush and reclaim dirty inodes in preparation for unmount. Inodes and
  * internal inode structures can be sitting in the CIL and AIL at this point,
  * so we need to unpin them, write them back and/or reclaim them before unmount
- * can proceed.
+ * can proceed.  In other words, callers are required to have inactivated all
+ * inodes.
  *
  * An inode cluster that has been freed can have its buffer still pinned in
  * memory because the transaction is still sitting in a iclog. The stale inodes
@@ -546,6 +547,7 @@ xfs_unmount_flush_inodes(
 	mp->m_flags |= XFS_MOUNT_UNMOUNTING;
 
 	xfs_ail_push_all_sync(mp->m_ail);
+	xfs_inodegc_stop(mp);
 	cancel_delayed_work_sync(&mp->m_reclaim_work);
 	xfs_reclaim_inodes(mp);
 	xfs_health_unmount(mp);
@@ -782,6 +784,9 @@ xfs_mountfs(
 	if (error)
 		goto out_log_dealloc;
 
+	/* Enable background inode inactivation workers. */
+	xfs_inodegc_start(mp);
+
 	/*
 	 * Get and sanity-check the root inode.
 	 * Save the pointer to it in the mount structure.
@@ -942,6 +947,15 @@ xfs_mountfs(
 	xfs_irele(rip);
 	/* Clean out dquots that might be in memory after quotacheck. */
 	xfs_qm_unmount(mp);
+
+	/*
+	 * Inactivate all inodes that might still be in memory after a log
+	 * intent recovery failure so that reclaim can free them.  Metadata
+	 * inodes and the root directory shouldn't need inactivation, but the
+	 * mount failed for some reason, so pull down all the state and flee.
+	 */
+	xfs_inodegc_flush(mp);
+
 	/*
 	 * Flush all inode reclamation work and flush the log.
 	 * We have to do this /after/ rtunmount and qm_unmount because those
@@ -989,6 +1003,16 @@ xfs_unmountfs(
 	uint64_t		resblks;
 	int			error;
 
+	/*
+	 * Perform all on-disk metadata updates required to inactivate inodes
+	 * that the VFS evicted earlier in the unmount process.  Freeing inodes
+	 * and discarding CoW fork preallocations can cause shape changes to
+	 * the free inode and refcount btrees, respectively, so we must finish
+	 * this before we discard the metadata space reservations.  Metadata
+	 * inodes and the root directory do not require inactivation.
+	 */
+	xfs_inodegc_flush(mp);
+
 	xfs_blockgc_stop(mp);
 	xfs_fs_unreserve_ag_blocks(mp);
 	xfs_qm_unmount_quotas(mp);
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index ed7064596f94..03d59a023bbb 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -56,6 +56,15 @@ struct xfs_error_cfg {
 	long		retry_timeout;	/* in jiffies, -1 = infinite */
 };
 
+/*
+ * Per-cpu deferred inode inactivation GC lists.
+ */
+struct xfs_inodegc {
+	struct llist_head	list;
+	struct work_struct	work;
+	unsigned int		items;
+};
+
 /*
  * The struct xfsmount layout is optimised to separate read-mostly variables
  * from variables that are frequently modified. We put the read-mostly variables
@@ -83,6 +92,8 @@ typedef struct xfs_mount {
 	xfs_buftarg_t		*m_logdev_targp;/* ptr to log device */
 	xfs_buftarg_t		*m_rtdev_targp;	/* ptr to rt device */
 	struct list_head	m_mount_list;	/* global mount list */
+	void __percpu		*m_inodegc;	/* percpu inodegc structures */
+
 	/*
 	 * Optional cache of rt summary level per bitmap block with the
 	 * invariant that m_rsum_cache[bbno] <= the minimum i for which
@@ -95,8 +106,9 @@ typedef struct xfs_mount {
 	struct workqueue_struct	*m_unwritten_workqueue;
 	struct workqueue_struct	*m_cil_workqueue;
 	struct workqueue_struct	*m_reclaim_workqueue;
-	struct workqueue_struct *m_gc_workqueue;
 	struct workqueue_struct	*m_sync_workqueue;
+	struct workqueue_struct *m_blockgc_wq;
+	struct workqueue_struct *m_inodegc_wq;
 
 	int			m_bsize;	/* fs logical block size */
 	uint8_t			m_blkbit_log;	/* blocklog + NBBY */
@@ -137,6 +149,7 @@ typedef struct xfs_mount {
 	struct xfs_ino_geometry	m_ino_geo;	/* inode geometry */
 	struct xfs_trans_resv	m_resv;		/* precomputed res values */
 						/* low free space thresholds */
+	unsigned long		m_opstate;	/* dynamic state flags */
 	bool			m_always_cow;
 	bool			m_fail_unmount;
 	bool			m_finobt_nores; /* no per-AG finobt resv. */
@@ -259,6 +272,29 @@ typedef struct xfs_mount {
 #define XFS_MOUNT_DAX_ALWAYS	(1ULL << 26)
 #define XFS_MOUNT_DAX_NEVER	(1ULL << 27)
 
+/*
+ * If set, inactivation worker threads will be scheduled to process queued
+ * inodegc work.  If not, queued inodes remain in memory waiting to be
+ * processed.
+ */
+#define XFS_STATE_INODEGC_ENABLED	0
+
+#define __XFS_IS_STATE(name, NAME) \
+static inline bool xfs_is_ ## name (struct xfs_mount *mp) \
+{ \
+	return test_bit(XFS_STATE_ ## NAME, &mp->m_opstate); \
+} \
+static inline bool xfs_clear_ ## name (struct xfs_mount *mp) \
+{ \
+	return test_and_clear_bit(XFS_STATE_ ## NAME, &mp->m_opstate); \
+} \
+static inline bool xfs_set_ ## name (struct xfs_mount *mp) \
+{ \
+	return test_and_set_bit(XFS_STATE_ ## NAME, &mp->m_opstate); \
+}
+
+__XFS_IS_STATE(inodegc_enabled, INODEGC_ENABLED)
+
 /*
  * Max and min values for mount-option defined I/O
  * preallocation sizes.
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index e0b97e4c8e16..ade192ea4230 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -530,21 +530,29 @@ xfs_init_mount_workqueues(
 	if (!mp->m_reclaim_workqueue)
 		goto out_destroy_cil;
 
-	mp->m_gc_workqueue = alloc_workqueue("xfs-gc/%s",
-			WQ_SYSFS | WQ_UNBOUND | WQ_FREEZABLE | WQ_MEM_RECLAIM,
+	mp->m_blockgc_wq = alloc_workqueue("xfs-blockgc/%s",
+			XFS_WQFLAGS(WQ_UNBOUND | WQ_FREEZABLE | WQ_MEM_RECLAIM),
 			0, mp->m_super->s_id);
-	if (!mp->m_gc_workqueue)
+	if (!mp->m_blockgc_wq)
 		goto out_destroy_reclaim;
 
+	mp->m_inodegc_wq = alloc_workqueue("xfs-inodegc/%s",
+			XFS_WQFLAGS(WQ_FREEZABLE | WQ_MEM_RECLAIM),
+			1, mp->m_super->s_id);
+	if (!mp->m_inodegc_wq)
+		goto out_destroy_blockgc;
+
 	mp->m_sync_workqueue = alloc_workqueue("xfs-sync/%s",
 			XFS_WQFLAGS(WQ_FREEZABLE), 0, mp->m_super->s_id);
 	if (!mp->m_sync_workqueue)
-		goto out_destroy_eofb;
+		goto out_destroy_inodegc;
 
 	return 0;
 
-out_destroy_eofb:
-	destroy_workqueue(mp->m_gc_workqueue);
+out_destroy_inodegc:
+	destroy_workqueue(mp->m_inodegc_wq);
+out_destroy_blockgc:
+	destroy_workqueue(mp->m_blockgc_wq);
 out_destroy_reclaim:
 	destroy_workqueue(mp->m_reclaim_workqueue);
 out_destroy_cil:
@@ -562,7 +570,8 @@ xfs_destroy_mount_workqueues(
 	struct xfs_mount	*mp)
 {
 	destroy_workqueue(mp->m_sync_workqueue);
-	destroy_workqueue(mp->m_gc_workqueue);
+	destroy_workqueue(mp->m_blockgc_wq);
+	destroy_workqueue(mp->m_inodegc_wq);
 	destroy_workqueue(mp->m_reclaim_workqueue);
 	destroy_workqueue(mp->m_cil_workqueue);
 	destroy_workqueue(mp->m_unwritten_workqueue);
@@ -724,6 +733,8 @@ xfs_fs_sync_fs(
 {
 	struct xfs_mount	*mp = XFS_M(sb);
 
+	trace_xfs_fs_sync_fs(mp, __return_address);
+
 	/*
 	 * Doing anything during the async pass would be counterproductive.
 	 */
@@ -740,6 +751,25 @@ xfs_fs_sync_fs(
 		flush_delayed_work(&mp->m_log->l_work);
 	}
 
+	/*
+	 * Flush all deferred inode inactivation work so that the free space
+	 * counters will reflect recent deletions.  Do not force the log again
+	 * because log recovery can restart the inactivation from the info that
+	 * we just wrote into the ondisk log.
+	 *
+	 * For regular operation this isn't strictly necessary since we aren't
+	 * required to guarantee that unlinking frees space immediately, but
+	 * that is how XFS historically behaved.
+	 *
+	 * If, however, the filesystem is at FREEZE_PAGEFAULTS, this is our
+	 * last chance to complete the inactivation work before the filesystem
+	 * freezes and the log is quiesced.  The background worker will not
+	 * activate again until the fs is thawed because the VFS won't evict
+	 * any more inodes until freeze_super drops s_umount and we disable the
+	 * worker in xfs_fs_freeze.
+	 */
+	xfs_inodegc_flush(mp);
+
 	return 0;
 }
 
@@ -854,6 +884,17 @@ xfs_fs_freeze(
 	 */
 	flags = memalloc_nofs_save();
 	xfs_blockgc_stop(mp);
+
+	/*
+	 * Stop the inodegc background worker.  freeze_super already flushed
+	 * all pending inodegc work when it sync'd the filesystem after setting
+	 * SB_FREEZE_PAGEFAULTS, and it holds s_umount, so we know that inodes
+	 * cannot enter xfs_fs_destroy_inode until the freeze is complete.
+	 * If the filesystem is read-write, inactivated inodes will queue but
+	 * the worker will not run until the filesystem thaws or unmounts.
+	 */
+	xfs_inodegc_stop(mp);
+
 	xfs_save_resvblks(mp);
 	ret = xfs_log_quiesce(mp);
 	memalloc_nofs_restore(flags);
@@ -869,6 +910,14 @@ xfs_fs_unfreeze(
 	xfs_restore_resvblks(mp);
 	xfs_log_work_queue(mp);
 	xfs_blockgc_start(mp);
+
+	/*
+	 * Don't reactivate the inodegc worker on a readonly filesystem because
+	 * inodes are sent directly to reclaim.
+	 */
+	if (!(mp->m_flags & XFS_MOUNT_RDONLY))
+		xfs_inodegc_start(mp);
+
 	return 0;
 }
 
@@ -994,6 +1043,35 @@ xfs_destroy_percpu_counters(
 	percpu_counter_destroy(&mp->m_delalloc_blks);
 }
 
+static int
+xfs_inodegc_init_percpu(
+	struct xfs_mount	*mp)
+{
+	struct xfs_inodegc	*gc;
+	int			cpu;
+
+	mp->m_inodegc = alloc_percpu(struct xfs_inodegc);
+	if (!mp->m_inodegc)
+		return -ENOMEM;
+
+	for_each_possible_cpu(cpu) {
+		gc = per_cpu_ptr(mp->m_inodegc, cpu);
+		init_llist_head(&gc->list);
+		gc->items = 0;
+                INIT_WORK(&gc->work, xfs_inodegc_worker);
+	}
+	return 0;
+}
+
+static void
+xfs_inodegc_free_percpu(
+	struct xfs_mount	*mp)
+{
+	if (!mp->m_inodegc)
+		return;
+	free_percpu(mp->m_inodegc);
+}
+
 static void
 xfs_fs_put_super(
 	struct super_block	*sb)
@@ -1011,6 +1089,7 @@ xfs_fs_put_super(
 	xfs_freesb(mp);
 	free_percpu(mp->m_stats.xs_stats);
 	xfs_mount_list_del(mp);
+	xfs_inodegc_free_percpu(mp);
 	xfs_destroy_percpu_counters(mp);
 	xfs_destroy_mount_workqueues(mp);
 	xfs_close_devices(mp);
@@ -1382,6 +1461,10 @@ xfs_fs_fill_super(
 	if (error)
 		goto out_destroy_workqueues;
 
+	error = xfs_inodegc_init_percpu(mp);
+	if (error)
+		goto out_destroy_counters;
+
 	/*
 	 * All percpu data structures requiring cleanup when a cpu goes offline
 	 * must be allocated before adding this @mp to the cpu-dead handler's
@@ -1393,7 +1476,7 @@ xfs_fs_fill_super(
 	mp->m_stats.xs_stats = alloc_percpu(struct xfsstats);
 	if (!mp->m_stats.xs_stats) {
 		error = -ENOMEM;
-		goto out_destroy_counters;
+		goto out_destroy_inodegc;
 	}
 
 	error = xfs_readsb(mp, flags);
@@ -1596,8 +1679,10 @@ xfs_fs_fill_super(
 	xfs_freesb(mp);
  out_free_stats:
 	free_percpu(mp->m_stats.xs_stats);
+ out_destroy_inodegc:
+	xfs_mount_list_del(mp);
+	xfs_inodegc_free_percpu(mp);
  out_destroy_counters:
-	xfs_mount_list_del(mp);
 	xfs_destroy_percpu_counters(mp);
  out_destroy_workqueues:
 	xfs_destroy_mount_workqueues(mp);
@@ -1680,6 +1765,9 @@ xfs_remount_rw(
 	if (error && error != -ENOSPC)
 		return error;
 
+	/* Re-enable the background inode inactivation worker. */
+	xfs_inodegc_start(mp);
+
 	return 0;
 }
 
@@ -1702,6 +1790,15 @@ xfs_remount_ro(
 		return error;
 	}
 
+	/*
+	 * Stop the inodegc background worker.  xfs_fs_reconfigure already
+	 * flushed all pending inodegc work when it sync'd the filesystem.
+	 * The VFS holds s_umount, so we know that inodes cannot enter
+	 * xfs_fs_destroy_inode during a remount operation.  In readonly mode
+	 * we send inodes straight to reclaim, so no inodes will be queued.
+	 */
+	xfs_inodegc_stop(mp);
+
 	/* Free the per-AG metadata reservation pool. */
 	error = xfs_fs_unreserve_ag_blocks(mp);
 	if (error) {
@@ -2102,7 +2199,7 @@ xfs_cpu_dead(
 	spin_lock(&xfs_mount_list_lock);
 	list_for_each_entry_safe(mp, n, &xfs_mount_list, m_mount_list) {
 		spin_unlock(&xfs_mount_list_lock);
-		/* xfs_subsys_dead(mp, cpu); */
+		xfs_inodegc_cpu_dead(mp, cpu);
 		spin_lock(&xfs_mount_list_lock);
 	}
 	spin_unlock(&xfs_mount_list_lock);
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 19260291ff8b..bd8abb50b33a 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -157,6 +157,48 @@ DEFINE_PERAG_REF_EVENT(xfs_perag_put);
 DEFINE_PERAG_REF_EVENT(xfs_perag_set_inode_tag);
 DEFINE_PERAG_REF_EVENT(xfs_perag_clear_inode_tag);
 
+#define XFS_STATE_FLAGS \
+	{ (1UL << XFS_STATE_INODEGC_ENABLED),		"inodegc" }
+
+DECLARE_EVENT_CLASS(xfs_fs_class,
+	TP_PROTO(struct xfs_mount *mp, void *caller_ip),
+	TP_ARGS(mp, caller_ip),
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__field(unsigned long long, mflags)
+		__field(unsigned long, opstate)
+		__field(unsigned long, sbflags)
+		__field(void *, caller_ip)
+	),
+	TP_fast_assign(
+		if (mp) {
+			__entry->dev = mp->m_super->s_dev;
+			__entry->mflags = mp->m_flags;
+			__entry->opstate = mp->m_opstate;
+			__entry->sbflags = mp->m_super->s_flags;
+		}
+		__entry->caller_ip = caller_ip;
+	),
+	TP_printk("dev %d:%d m_flags 0x%llx opstate (%s) s_flags 0x%lx caller %pS",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->mflags,
+		  __print_flags(__entry->opstate, "|", XFS_STATE_FLAGS),
+		  __entry->sbflags,
+		  __entry->caller_ip)
+);
+
+#define DEFINE_FS_EVENT(name)	\
+DEFINE_EVENT(xfs_fs_class, name,					\
+	TP_PROTO(struct xfs_mount *mp, void *caller_ip), \
+	TP_ARGS(mp, caller_ip))
+DEFINE_FS_EVENT(xfs_inodegc_flush);
+DEFINE_FS_EVENT(xfs_inodegc_start);
+DEFINE_FS_EVENT(xfs_inodegc_stop);
+DEFINE_FS_EVENT(xfs_inodegc_worker);
+DEFINE_FS_EVENT(xfs_inodegc_queue);
+DEFINE_FS_EVENT(xfs_inodegc_throttle);
+DEFINE_FS_EVENT(xfs_fs_sync_fs);
+
 DECLARE_EVENT_CLASS(xfs_ag_class,
 	TP_PROTO(struct xfs_mount *mp, xfs_agnumber_t agno),
 	TP_ARGS(mp, agno),
@@ -616,14 +658,17 @@ DECLARE_EVENT_CLASS(xfs_inode_class,
 	TP_STRUCT__entry(
 		__field(dev_t, dev)
 		__field(xfs_ino_t, ino)
+		__field(unsigned long, iflags)
 	),
 	TP_fast_assign(
 		__entry->dev = VFS_I(ip)->i_sb->s_dev;
 		__entry->ino = ip->i_ino;
+		__entry->iflags = ip->i_flags;
 	),
-	TP_printk("dev %d:%d ino 0x%llx",
+	TP_printk("dev %d:%d ino 0x%llx iflags 0x%lx",
 		  MAJOR(__entry->dev), MINOR(__entry->dev),
-		  __entry->ino)
+		  __entry->ino,
+		  __entry->iflags)
 )
 
 #define DEFINE_INODE_EVENT(name) \
@@ -667,6 +712,10 @@ DEFINE_INODE_EVENT(xfs_inode_free_eofblocks_invalid);
 DEFINE_INODE_EVENT(xfs_inode_set_cowblocks_tag);
 DEFINE_INODE_EVENT(xfs_inode_clear_cowblocks_tag);
 DEFINE_INODE_EVENT(xfs_inode_free_cowblocks_invalid);
+DEFINE_INODE_EVENT(xfs_inode_set_reclaimable);
+DEFINE_INODE_EVENT(xfs_inode_reclaiming);
+DEFINE_INODE_EVENT(xfs_inode_set_need_inactive);
+DEFINE_INODE_EVENT(xfs_inode_inactivating);
 
 /*
  * ftrace's __print_symbolic requires that all enum values be wrapped in the
