Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 393da918 authored by Liu Bo's avatar Liu Bo Committed by David Sterba
Browse files

Btrfs: add tracepoint for em's EEXIST case 



This is adding a tracepoint 'btrfs_handle_em_exist' to help debug the
subtle bugs around merge_extent_mapping.

Signed-off-by: default avatarLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: default avatarJosef Bacik <jbacik@fb.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 5d23515b

fs/btrfs/extent_map.c

+3 −0
Original line number Diff line number Diff line
@@ -551,6 +551,9 @@ int btrfs_add_extent_mapping(struct extent_map_tree *em_tree, 
		ret = 0;



		existing = search_extent_mapping(em_tree, start, len);



		trace_btrfs_handle_em_exist(existing, em, start, len);



		/*

		 * existing will always be non-NULL, since there must be

		 * extent causing the -EEXIST.

include/trace/events/btrfs.h

+35 −0
Original line number Diff line number Diff line
@@ -248,6 +248,41 @@ TRACE_EVENT_CONDITION(btrfs_get_extent, 
		  __entry->refs, __entry->compress_type)

);



TRACE_EVENT(btrfs_handle_em_exist,



	TP_PROTO(const struct extent_map *existing, const struct extent_map *map, u64 start, u64 len),



	TP_ARGS(existing, map, start, len),



	TP_STRUCT__entry(

		__field(	u64,  e_start		)

		__field(	u64,  e_len		)

		__field(	u64,  map_start		)

		__field(	u64,  map_len		)

		__field(	u64,  start		)

		__field(	u64,  len		)

	),



	TP_fast_assign(

		__entry->e_start	= existing->start;

		__entry->e_len		= existing->len;

		__entry->map_start	= map->start;

		__entry->map_len	= map->len;

		__entry->start		= start;

		__entry->len		= len;

	),



	TP_printk("start=%llu len=%llu "

		  "existing(start=%llu len=%llu) "

		  "em(start=%llu len=%llu)",

		  (unsigned long long)__entry->start,

		  (unsigned long long)__entry->len,

		  (unsigned long long)__entry->e_start,

		  (unsigned long long)__entry->e_len,

		  (unsigned long long)__entry->map_start,

		  (unsigned long long)__entry->map_len)

);



/* file extent item */

DECLARE_EVENT_CLASS(btrfs__file_extent_item_regular,