btrfs: add tracepoints for extent map shrinker events

Add some tracepoints for the extent map shrinker to help debug and analyse
main events. These have proved useful during development of the shrinker.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 99 insertions, 0 deletions

diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h
index 8f2497603cb5..d2d94d7c3fb5 100644
--- a/include/trace/events/btrfs.h
+++ b/include/trace/events/btrfs.h
@@ -2537,6 +2537,105 @@ TRACE_EVENT(btrfs_get_raid_extent_offset,
 			__entry->devid)
 );
 
+TRACE_EVENT(btrfs_extent_map_shrinker_count,
+
+	TP_PROTO(const struct btrfs_fs_info *fs_info, long nr),
+
+	TP_ARGS(fs_info, nr),
+
+	TP_STRUCT__entry_btrfs(
+		__field(	long,	nr	)
+	),
+
+	TP_fast_assign_btrfs(fs_info,
+		__entry->nr		= nr;
+	),
+
+	TP_printk_btrfs("nr=%ld", __entry->nr)
+);
+
+TRACE_EVENT(btrfs_extent_map_shrinker_scan_enter,
+
+	TP_PROTO(const struct btrfs_fs_info *fs_info, long nr_to_scan, long nr),
+
+	TP_ARGS(fs_info, nr_to_scan, nr),
+
+	TP_STRUCT__entry_btrfs(
+		__field(	long,	nr_to_scan	)
+		__field(	long,	nr		)
+		__field(	u64,	last_root_id	)
+		__field(	u64,	last_ino	)
+	),
+
+	TP_fast_assign_btrfs(fs_info,
+		__entry->nr_to_scan	= nr_to_scan;
+		__entry->nr		= nr;
+		__entry->last_root_id	= fs_info->extent_map_shrinker_last_root;
+		__entry->last_ino	= fs_info->extent_map_shrinker_last_ino;
+	),
+
+	TP_printk_btrfs("nr_to_scan=%ld nr=%ld last_root=%llu(%s) last_ino=%llu",
+			__entry->nr_to_scan, __entry->nr,
+			show_root_type(__entry->last_root_id), __entry->last_ino)
+);
+
+TRACE_EVENT(btrfs_extent_map_shrinker_scan_exit,
+
+	TP_PROTO(const struct btrfs_fs_info *fs_info, long nr_dropped, long nr),
+
+	TP_ARGS(fs_info, nr_dropped, nr),
+
+	TP_STRUCT__entry_btrfs(
+		__field(	long,	nr_dropped	)
+		__field(	long,	nr		)
+		__field(	u64,	last_root_id	)
+		__field(	u64,	last_ino	)
+	),
+
+	TP_fast_assign_btrfs(fs_info,
+		__entry->nr_dropped	= nr_dropped;
+		__entry->nr		= nr;
+		__entry->last_root_id	= fs_info->extent_map_shrinker_last_root;
+		__entry->last_ino	= fs_info->extent_map_shrinker_last_ino;
+	),
+
+	TP_printk_btrfs("nr_dropped=%ld nr=%ld last_root=%llu(%s) last_ino=%llu",
+			__entry->nr_dropped, __entry->nr,
+			show_root_type(__entry->last_root_id), __entry->last_ino)
+);
+
+TRACE_EVENT(btrfs_extent_map_shrinker_remove_em,
+
+	TP_PROTO(const struct btrfs_inode *inode, const struct extent_map *em),
+
+	TP_ARGS(inode, em),
+
+	TP_STRUCT__entry_btrfs(
+		__field(	u64,	ino		)
+		__field(	u64,	root_id		)
+		__field(	u64,	start		)
+		__field(	u64,	len		)
+		__field(	u64,	block_start	)
+		__field(	u32,	flags		)
+	),
+
+	TP_fast_assign_btrfs(inode->root->fs_info,
+		__entry->ino		= btrfs_ino(inode);
+		__entry->root_id	= inode->root->root_key.objectid;
+		__entry->start		= em->start;
+		__entry->len		= em->len;
+		__entry->block_start	= em->block_start;
+		__entry->flags		= em->flags;
+	),
+
+	TP_printk_btrfs(
+"ino=%llu root=%llu(%s) start=%llu len=%llu block_start=%llu(%s) flags=%s",
+			__entry->ino, show_root_type(__entry->root_id),
+			__entry->start, __entry->len,
+			show_map_type(__entry->block_start),
+			show_map_flags(__entry->flags))
+);
+
 #endif /* _TRACE_BTRFS_H */
 
 /* This part must be outside protection */