@@ -6354,6 +6354,7 @@ static int update_block_group(struct btrfs_trans_handle *trans,
spin_lock(&info->unused_bgs_lock);
if (list_empty(&cache->bg_list)) {
btrfs_get_block_group(cache);
+ trace_btrfs_add_unused_block_group(cache);
list_add_tail(&cache->bg_list,
&info->unused_bgs);
}
@@ -10204,6 +10205,7 @@ int btrfs_read_block_groups(struct btrfs_fs_info *info)
/* Should always be true but just in case. */
if (list_empty(&cache->bg_list)) {
btrfs_get_block_group(cache);
+ trace_btrfs_add_unused_block_group(cache);
list_add_tail(&cache->bg_list,
&info->unused_bgs);
}
@@ -10391,6 +10393,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
BUG_ON(!block_group);
BUG_ON(!block_group->ro);
+ trace_btrfs_remove_block_group(block_group);
/*
* Free the reserved super bytes from this block group before
* remove it.
@@ -10755,6 +10758,7 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
* the ro check in case balance is currently acting on
* this block group.
*/
+ trace_btrfs_skip_unused_block_group(block_group);
spin_unlock(&block_group->lock);
up_write(&space_info->groups_sem);
goto next;
@@ -3984,6 +3984,7 @@ int scrub_enumerate_chunks(struct scrub_ctx *sctx,
spin_lock(&fs_info->unused_bgs_lock);
if (list_empty(&cache->bg_list)) {
btrfs_get_block_group(cache);
+ trace_btrfs_add_unused_block_group(cache);
list_add_tail(&cache->bg_list,
&fs_info->unused_bgs);
}
@@ -1810,6 +1810,48 @@ TRACE_EVENT(btrfs_inode_mod_outstanding_extents,
show_root_type(__entry->root_objectid),
(unsigned long long)__entry->ino, __entry->mod)
);
+
+DECLARE_EVENT_CLASS(btrfs__block_group,
+ TP_PROTO(const struct btrfs_block_group_cache *bg_cache),
+
+ TP_ARGS(bg_cache),
+
+ TP_STRUCT__entry_btrfs(
+ __field( u64, bytenr )
+ __field( u64, flags )
+ __field( u64, len )
+ __field( u64, used )
+ ),
+
+ TP_fast_assign_btrfs(bg_cache->fs_info,
+ __entry->bytenr = bg_cache->key.objectid,
+ __entry->len = bg_cache->key.offset,
+ __entry->flags = bg_cache->flags;
+ __entry->used = btrfs_block_group_used(&bg_cache->item);
+ ),
+
+ TP_printk_btrfs("bg bytenr=%llu len=%llu used=%llu flags=%llu(%s)",
+ __entry->bytenr, __entry->len, __entry->used, __entry->flags,
+ __print_flags(__entry->flags, "|", BTRFS_GROUP_FLAGS))
+);
+
+DEFINE_EVENT(btrfs__block_group, btrfs_remove_block_group,
+ TP_PROTO(const struct btrfs_block_group_cache *bg_cache),
+
+ TP_ARGS(bg_cache)
+);
+
+DEFINE_EVENT(btrfs__block_group, btrfs_add_unused_block_group,
+ TP_PROTO(const struct btrfs_block_group_cache *bg_cache),
+
+ TP_ARGS(bg_cache)
+);
+
+DEFINE_EVENT(btrfs__block_group, btrfs_skip_unused_block_group,
+ TP_PROTO(const struct btrfs_block_group_cache *bg_cache),
+
+ TP_ARGS(bg_cache)
+);
#endif /* _TRACE_BTRFS_H */
/* This part must be outside protection */
This patch will add the following trace events: 1) btrfs_remove_block_group For btrfs_remove_block_group() function. Triggered when a block group is really removed. 2) btrfs_add_unused_block_group Triggered which block group is added to unused_bgs list. 3) btrfs_skip_unused_block_group Triggered which unused block group is not deleted. These trace events is pretty handy to debug case related to block group auto remove. Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/extent-tree.c | 4 ++++ fs/btrfs/scrub.c | 1 + include/trace/events/btrfs.h | 42 ++++++++++++++++++++++++++++++++++++ 3 files changed, 47 insertions(+)