5 files changed, 95 insertions, 0 deletions

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index 8169a1465db1..11e0a633fd76 100644
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -1983,6 +1983,7 @@ end:
 
 void btrfs_reclaim_bgs(struct btrfs_fs_info *fs_info)
 {
+	btrfs_reclaim_sweep(fs_info);
 	spin_lock(&fs_info->unused_bgs_lock);
 	if (!list_empty(&fs_info->reclaim_bgs))
 		queue_work(system_unbound_wq, &fs_info->reclaim_bgs_work);
@@ -3681,6 +3682,7 @@ int btrfs_update_block_group(struct btrfs_trans_handle *trans,
 		old_val += num_bytes;
 		cache->used = old_val;
 		cache->reserved -= num_bytes;
+		cache->reclaim_mark = 0;
 		space_info->bytes_reserved -= num_bytes;
 		space_info->bytes_used += num_bytes;
 		space_info->disk_used += num_bytes * factor;
diff --git a/fs/btrfs/block-group.h b/fs/btrfs/block-group.h
index 85e2d4cd12dc..8656b38f1fa5 100644
--- a/fs/btrfs/block-group.h
+++ b/fs/btrfs/block-group.h
@@ -263,6 +263,7 @@ struct btrfs_block_group {
 	struct work_struct zone_finish_work;
 	struct extent_buffer *last_eb;
 	enum btrfs_block_group_size_class size_class;
+	u64 reclaim_mark;
 };
 
 static inline u64 btrfs_block_group_end(struct btrfs_block_group *block_group)
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 5b1940432ff3..75ffe8c99b0a 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -1969,3 +1969,54 @@ int btrfs_calc_reclaim_threshold(struct btrfs_space_info *space_info)
 		return calc_dynamic_reclaim_threshold(space_info);
 	return READ_ONCE(space_info->bg_reclaim_threshold);
 }
+
+static int do_reclaim_sweep(struct btrfs_fs_info *fs_info,
+			    struct btrfs_space_info *space_info, int raid)
+{
+	struct btrfs_block_group *bg;
+	int thresh_pct;
+
+	spin_lock(&space_info->lock);
+	thresh_pct = btrfs_calc_reclaim_threshold(space_info);
+	spin_unlock(&space_info->lock);
+
+	down_read(&space_info->groups_sem);
+	list_for_each_entry(bg, &space_info->block_groups[raid], list) {
+		u64 thresh;
+		bool reclaim = false;
+
+		btrfs_get_block_group(bg);
+		spin_lock(&bg->lock);
+		thresh = mult_perc(bg->length, thresh_pct);
+		if (bg->used < thresh && bg->reclaim_mark)
+			reclaim = true;
+		bg->reclaim_mark++;
+		spin_unlock(&bg->lock);
+		if (reclaim)
+			btrfs_mark_bg_to_reclaim(bg);
+		btrfs_put_block_group(bg);
+	}
+	up_read(&space_info->groups_sem);
+	return 0;
+}
+
+int btrfs_reclaim_sweep(struct btrfs_fs_info *fs_info)
+{
+	int ret;
+	int raid;
+	struct btrfs_space_info *space_info;
+
+	list_for_each_entry(space_info, &fs_info->space_info, list) {
+		if (space_info->flags & BTRFS_BLOCK_GROUP_SYSTEM)
+			continue;
+		if (!READ_ONCE(space_info->periodic_reclaim))
+			continue;
+		for (raid = 0; raid < BTRFS_NR_RAID_TYPES; raid++) {
+			ret = do_reclaim_sweep(fs_info, space_info, raid);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return ret;
+}
diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h
index 2cac771321c7..ae4a1f7d5856 100644
--- a/fs/btrfs/space-info.h
+++ b/fs/btrfs/space-info.h
@@ -190,6 +190,12 @@ struct btrfs_space_info {
 	 * fixed bg_reclaim_threshold.
 	 */
 	bool dynamic_reclaim;
+
+	/*
+	 * Periodically check all block groups against the reclaim
+	 * threshold in the cleaner thread.
+	 */
+	bool periodic_reclaim;
 };
 
 struct reserve_ticket {
@@ -273,5 +279,6 @@ void btrfs_init_async_reclaim_work(struct btrfs_fs_info *fs_info);
 u64 btrfs_account_ro_block_groups_free_space(struct btrfs_space_info *sinfo);
 
 int btrfs_calc_reclaim_threshold(struct btrfs_space_info *space_info);
+int btrfs_reclaim_sweep(struct btrfs_fs_info *fs_info);
 
 #endif /* BTRFS_SPACE_INFO_H */
diff --git a/fs/btrfs/sysfs.c b/fs/btrfs/sysfs.c
index 360d6093476f..c58cea0da597 100644
--- a/fs/btrfs/sysfs.c
+++ b/fs/btrfs/sysfs.c
@@ -973,6 +973,39 @@ BTRFS_ATTR_RW(space_info, dynamic_reclaim,
 	      btrfs_sinfo_dynamic_reclaim_show,
 	      btrfs_sinfo_dynamic_reclaim_store);
 
+static ssize_t btrfs_sinfo_periodic_reclaim_show(struct kobject *kobj,
+						struct kobj_attribute *a,
+						char *buf)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+
+	return sysfs_emit(buf, "%d\n", READ_ONCE(space_info->periodic_reclaim));
+}
+
+static ssize_t btrfs_sinfo_periodic_reclaim_store(struct kobject *kobj,
+						 struct kobj_attribute *a,
+						 const char *buf, size_t len)
+{
+	struct btrfs_space_info *space_info = to_space_info(kobj);
+	int periodic_reclaim;
+	int ret;
+
+	ret = kstrtoint(buf, 10, &periodic_reclaim);
+	if (ret)
+		return ret;
+
+	if (periodic_reclaim < 0)
+		return -EINVAL;
+
+	WRITE_ONCE(space_info->periodic_reclaim, periodic_reclaim != 0);
+
+	return len;
+}
+
+BTRFS_ATTR_RW(space_info, periodic_reclaim,
+	      btrfs_sinfo_periodic_reclaim_show,
+	      btrfs_sinfo_periodic_reclaim_store);
+
 /*
  * Allocation information about block group types.
  *
@@ -996,6 +1029,7 @@ static struct attribute *space_info_attrs[] = {
 	BTRFS_ATTR_PTR(space_info, reclaim_count),
 	BTRFS_ATTR_PTR(space_info, reclaim_bytes),
 	BTRFS_ATTR_PTR(space_info, reclaim_errors),
+	BTRFS_ATTR_PTR(space_info, periodic_reclaim),
 #ifdef CONFIG_BTRFS_DEBUG
 	BTRFS_ATTR_PTR(space_info, force_chunk_alloc),
 #endif