diff mbox series

[10/13] btrfs: zoned: activate metadata BG on flush_space

Message ID bedcc3526ff4acc1e83ce7fdd6aa4fd41d3d0461.1656909695.git.naohiro.aota@wdc.com (mailing list archive)
State New, archived
Headers show
Series btrfs: zoned: fix active zone tracking issues | expand

Commit Message

Naohiro Aota July 4, 2022, 4:58 a.m. UTC
For metadata space on zoned btrfs, reaching ALLOC_CHUNK{,_FORCE} means we
don't have enough space left in the active_total_bytes. Before allocating a
new chunk, we can try to activate an existing block group in this case.

Also, allocating a chunk is not enough to grant a ticket for metadata space
on zoned btrfs. We need to activate the block group to increase the
active_total_bytes.

btrfs_zoned_activate_one_bg() implements the activation feature. It will
activate a block group by (maybe) finishing a block group. It will give up
activating a block group if it cannot finish any block group.

CC: stable@vger.kernel.org # 5.16+
Fixes: afba2bc036b0 ("btrfs: zoned: implement active zone tracking")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
---
 fs/btrfs/space-info.c | 20 +++++++++++++++++++
 fs/btrfs/zoned.c      | 45 +++++++++++++++++++++++++++++++++++++++++++
 fs/btrfs/zoned.h      | 10 ++++++++++
 3 files changed, 75 insertions(+)

Comments

Johannes Thumshirn July 7, 2022, 2:51 p.m. UTC | #1
Looks good,
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
diff mbox series

Patch

diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index 4ce9dfbabd97..f35f36d89660 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -9,6 +9,7 @@ 
 #include "ordered-data.h"
 #include "transaction.h"
 #include "block-group.h"
+#include "zoned.h"
 
 /*
  * HOW DOES SPACE RESERVATION WORK
@@ -724,6 +725,15 @@  static void flush_space(struct btrfs_fs_info *fs_info,
 		break;
 	case ALLOC_CHUNK:
 	case ALLOC_CHUNK_FORCE:
+		/*
+		 * For metadata space on zoned btrfs, reaching here means we
+		 * don't have enough space left in active_total_bytes. Try to
+		 * activate a block group first, because we may have inactive
+		 * block group already allocated.
+		 */
+		if (btrfs_zoned_activate_one_bg(fs_info, space_info, false))
+			break;
+
 		trans = btrfs_join_transaction(root);
 		if (IS_ERR(trans)) {
 			ret = PTR_ERR(trans);
@@ -734,6 +744,16 @@  static void flush_space(struct btrfs_fs_info *fs_info,
 				(state == ALLOC_CHUNK) ? CHUNK_ALLOC_NO_FORCE :
 					CHUNK_ALLOC_FORCE);
 		btrfs_end_transaction(trans);
+
+		/*
+		 * For metadata space on zoned btrfs, allocating a new chunk is
+		 * not enough. We still need to activate the block group. Active
+		 * the newly allocated block group by (maybe) finishing a block
+		 * group.
+		 */
+		if (ret == 1)
+			btrfs_zoned_activate_one_bg(fs_info, space_info, true);
+
 		if (ret > 0 || ret == -ENOSPC)
 			ret = 0;
 		break;
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 9cabf088b800..6441a311e658 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -2234,3 +2234,48 @@  bool btrfs_finish_one_bg(struct btrfs_fs_info *fs_info)
 
 	return ret == 0;
 }
+
+bool btrfs_zoned_activate_one_bg(struct btrfs_fs_info *fs_info,
+				 struct btrfs_space_info *space_info,
+				 bool do_finish)
+{
+	struct btrfs_block_group *bg;
+	bool need_finish;
+	int index;
+
+	if (!btrfs_is_zoned(fs_info) || (space_info->flags & BTRFS_BLOCK_GROUP_DATA))
+		return false;
+
+	/* No more block group to activate */
+	if (space_info->active_total_bytes == space_info->total_bytes)
+		return false;
+
+	for (;;) {
+		need_finish = false;
+		down_read(&space_info->groups_sem);
+		for (index = 0; index < BTRFS_NR_RAID_TYPES; index++) {
+			list_for_each_entry(bg, &space_info->block_groups[index], list) {
+				if (!spin_trylock(&bg->lock))
+					continue;
+				if (bg->zone_is_active) {
+					spin_unlock(&bg->lock);
+					continue;
+				}
+				spin_unlock(&bg->lock);
+
+				if (btrfs_zone_activate(bg)) {
+					up_read(&space_info->groups_sem);
+					return true;
+				}
+
+				need_finish = true;
+			}
+		}
+		up_read(&space_info->groups_sem);
+
+		if (!do_finish || !need_finish || !btrfs_finish_one_bg(fs_info))
+			break;
+	}
+
+	return false;
+}
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index 09a19772ee68..1beca00c69fc 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -81,6 +81,8 @@  bool btrfs_zoned_should_reclaim(struct btrfs_fs_info *fs_info);
 void btrfs_zoned_release_data_reloc_bg(struct btrfs_fs_info *fs_info, u64 logical,
 				       u64 length);
 bool btrfs_finish_one_bg(struct btrfs_fs_info *fs_info);
+bool btrfs_zoned_activate_one_bg(struct btrfs_fs_info *fs_info,
+				 struct btrfs_space_info *space_info, bool do_finish);
 #else /* CONFIG_BLK_DEV_ZONED */
 static inline int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
 				     struct blk_zone *zone)
@@ -256,6 +258,14 @@  static inline bool btrfs_finish_one_bg(struct btrfs_fs_info *fs_info)
 	return true;
 }
 
+static inline bool btrfs_zoned_activate_one_bg(struct btrfs_fs_info *fs_info,
+					       struct btrfs_space_info *space_info,
+					       bool do_finish)
+{
+	/* Consider all the BGs are active */
+	return false;
+}
+
 #endif
 
 static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)