Filipe Manana fd0ddbe250 Btrfs: send, skip backreference walking for extents with many references ... Backreference walking, which is used by send to figure if it can issue clone operations instead of write operations, can be very slow and use too much memory when extents have many references. This change simply skips backreference walking when an extent has more than 64 references, in which case we fallback to a write operation instead of a clone operation. This limit is conservative and in practice I observed no signicant slowdown with up to 100 references and still low memory usage up to that limit. This is a temporary workaround until there are speedups in the backref walking code, and as such it does not attempt to add extra interfaces or knobs to tweak the threshold. Reported-by: Atemu <atemu.main@gmail.com> Link: https://lore.kernel.org/linux-btrfs/CAE4GHgkvqVADtS4AzcQJxo0Q1jKQgKaW3JGp3SGdoinVo=C9eQ@mail.gmail.com/T/#me55dc0987f9cc2acaa54372ce0492c65782be3fa CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>		2019-11-18 17:51:48 +01:00
..
tests	btrfs: add dedicated members for start and length of a block group	2019-11-18 17:51:45 +01:00
acl.c	btrfs: cleanup btrfs_setxattr_trans and drop transaction parameter	2019-04-29 19:02:44 +02:00
async-thread.c	btrfs: add __pure attribute to functions	2019-11-18 12:46:52 +01:00
async-thread.h	btrfs: add __pure attribute to functions	2019-11-18 12:46:52 +01:00
backref.c	Btrfs: fix deadlock between fiemap and transaction commits	2019-07-30 18:25:12 +02:00
backref.h	btrfs: fiemap: preallocate ulists for btrfs_check_shared	2019-07-01 13:34:53 +02:00
block-group.c	btrfs: add dedicated members for start and length of a block group	2019-11-18 17:51:45 +01:00
block-group.h	btrfs: add dedicated members for start and length of a block group	2019-11-18 17:51:45 +01:00
block-rsv.c	btrfs: use btrfs_try_granting_tickets in update_global_rsv	2019-09-09 14:59:19 +02:00
block-rsv.h	btrfs: migrate the global_block_rsv helpers to block-rsv.c	2019-07-02 12:30:55 +02:00
btrfs_inode.h	Btrfs: remove unnecessary delalloc mutex for inodes	2019-11-18 17:51:46 +01:00
check-integrity.c	btrfs: reduce stack usage for btrfsic_process_written_block	2019-09-09 14:58:58 +02:00
check-integrity.h	btrfs: replace GPL boilerplate by SPDX -- headers	2018-04-12 16:29:46 +02:00
compression.c	btrfs: compression: remove ops pointer from workspace_manager	2019-11-18 12:46:59 +01:00
compression.h	btrfs: compression: remove ops pointer from workspace_manager	2019-11-18 12:46:59 +01:00
ctree.c	btrfs: add blake2b to checksumming algorithms	2019-11-18 17:51:44 +01:00
ctree.h	btrfs: rename extent buffer block group item accessors	2019-11-18 17:51:45 +01:00
delalloc-space.c	Btrfs: remove unnecessary delalloc mutex for inodes	2019-11-18 17:51:46 +01:00
delalloc-space.h	btrfs: migrate the delalloc space stuff to it's own home	2019-07-04 17:26:17 +02:00
delayed-inode.c	btrfs: use refcount_inc_not_zero in kill_all_nodes	2019-11-18 12:46:51 +01:00
delayed-inode.h	Btrfs: delayed-inode: use rb_first_cached for ins_root and del_root	2018-10-15 17:23:33 +02:00
delayed-ref.c	btrfs: rename btrfs_space_info_add_old_bytes	2019-09-09 14:59:18 +02:00
delayed-ref.h	btrfs: migrate the delayed refs rsv code	2019-07-04 17:26:17 +02:00
dev-replace.c	btrfs: add __pure attribute to functions	2019-11-18 12:46:52 +01:00
dev-replace.h	btrfs: add __pure attribute to functions	2019-11-18 12:46:52 +01:00
dir-item.c	btrfs: remove unused parameter fs_info from btrfs_extend_item	2019-04-29 19:02:50 +02:00
disk-io.c	btrfs: Streamline btrfs_fs_info::backup_root_index semantics	2019-11-18 17:51:47 +01:00
disk-io.h	btrfs: add __cold attribute to more functions	2019-11-18 12:46:52 +01:00
export.c	btrfs: drop unused parameter is_new from btrfs_iget	2019-11-18 12:46:52 +01:00
export.h	btrfs: replace GPL boilerplate by SPDX -- headers	2018-04-12 16:29:46 +02:00
extent_io.c	btrfs: Avoid getting stuck during cyclic writebacks	2019-11-18 12:46:54 +01:00
extent_io.h	btrfs: opencode extent_buffer_get	2019-11-18 12:46:54 +01:00
extent_map.c	btrfs: assert extent_map bdevs and lookup_map and split	2019-11-18 12:47:01 +01:00
extent_map.h	btrfs: assert extent_map bdevs and lookup_map and split	2019-11-18 12:47:01 +01:00
extent-io-tree.h	btrfs: move the failrec tree stuff into extent-io-tree.h	2019-11-18 12:46:47 +01:00
extent-tree.c	btrfs: Ensure we trim ranges across block group boundary	2019-11-18 17:51:48 +01:00
file-item.c	btrfs: directly call into crypto framework for checksumming	2019-07-01 13:35:02 +02:00
file.c	btrfs: Return offset from find_desired_extent	2019-11-18 12:47:00 +01:00
free-space-cache.c	btrfs: add dedicated members for start and length of a block group	2019-11-18 17:51:45 +01:00
free-space-cache.h	btrfs: move struct io_ctl to free-space-cache.h	2019-09-09 14:59:15 +02:00
free-space-tree.c	btrfs: add dedicated members for start and length of a block group	2019-11-18 17:51:45 +01:00
free-space-tree.h	btrfs: move basic block_group definitions to their own header	2019-09-09 14:59:03 +02:00
inode-item.c	btrfs: Make btrfs_find_name_in_ext_backref return struct btrfs_inode_extref	2019-09-09 14:59:16 +02:00
inode-map.c	btrfs: qgroup: Always free PREALLOC META reserve in btrfs_delalloc_release_extents()	2019-10-15 18:50:07 +02:00
inode-map.h	btrfs: replace GPL boilerplate by SPDX -- headers	2018-04-12 16:29:46 +02:00
inode.c	Btrfs: remove unnecessary delalloc mutex for inodes	2019-11-18 17:51:46 +01:00
ioctl.c	btrfs: add dedicated members for start and length of a block group	2019-11-18 17:51:45 +01:00
Kconfig	btrfs: add sha256 to checksumming algorithm	2019-11-18 17:51:43 +01:00
locking.c	btrfs: move btrfs_unlock_up_safe to other locking functions	2019-11-18 12:46:49 +01:00
locking.h	btrfs: move btrfs_unlock_up_safe to other locking functions	2019-11-18 12:46:49 +01:00
lzo.c	btrfs: compression: inline free_workspace	2019-11-18 12:46:59 +01:00
Makefile	btrfs: migrate the block group lookup code	2019-09-09 14:59:04 +02:00
misc.h	btrfs: add 64bit safe helper for power of two checks	2019-11-18 12:46:50 +01:00
ordered-data.c	btrfs: get rid of unique workqueue helper functions	2019-11-18 12:46:48 +01:00
ordered-data.h	btrfs: don't assume ordered sums to be 4 bytes	2019-07-01 13:35:00 +02:00
orphan.c	btrfs: replace GPL boilerplate by SPDX -- sources	2018-04-12 16:29:51 +02:00
print-tree.c	btrfs: rename extent buffer block group item accessors	2019-11-18 17:51:45 +01:00
print-tree.h	btrfs: print-tree: debugging output enhancement	2018-04-20 19:18:16 +02:00
props.c	btrfs: props: remove unnecessary hash_init()	2019-11-18 12:46:55 +01:00
props.h	btrfs: delete unused function btrfs_set_prop_trans	2019-04-29 19:02:54 +02:00
qgroup.c	btrfs: opencode extent_buffer_get	2019-11-18 12:46:54 +01:00
qgroup.h	btrfs: qgroup: Move reserved data accounting from btrfs_delayed_ref_head to btrfs_qgroup_extent_record	2019-02-25 14:13:39 +01:00
raid56.c	btrfs: remove pointless local variable in lock_stripe_add()	2019-11-18 12:47:00 +01:00
raid56.h	btrfs: constify map parameter for nr_parity_stripes and nr_data_stripes	2019-07-01 13:34:58 +02:00
rcu-string.h	btrfs: replace GPL boilerplate by SPDX -- headers	2018-04-12 16:29:46 +02:00
reada.c	btrfs: add dedicated members for start and length of a block group	2019-11-18 17:51:45 +01:00
ref-verify.c	btrfs: fix uninitialized ret in ref-verify	2019-10-03 15:00:56 +02:00
ref-verify.h	btrfs: ref-verify: Use btrfs_ref to refactor btrfs_ref_tree_mod()	2019-04-29 19:02:49 +02:00
relocation.c	btrfs: add dedicated members for start and length of a block group	2019-11-18 17:51:45 +01:00
root-tree.c	btrfs: rename the btrfs_calc_*_metadata_size helpers	2019-09-09 14:59:13 +02:00
scrub.c	btrfs: clean up locking name in scrub_enumerate_chunks()	2019-11-18 17:51:47 +01:00
send.c	Btrfs: send, skip backreference walking for extents with many references	2019-11-18 17:51:48 +01:00
send.h	btrfs: replace GPL boilerplate by SPDX -- headers	2018-04-12 16:29:46 +02:00
space-info.c	Btrfs: remove wait queue from space_info structure	2019-11-18 17:51:46 +01:00
space-info.h	Btrfs: remove wait queue from space_info structure	2019-11-18 17:51:46 +01:00
struct-funcs.c	btrfs: tie extent buffer and it's token together	2019-09-09 14:59:16 +02:00
super.c	btrfs: remove cached space_info in btrfs_statfs()	2019-11-18 17:51:45 +01:00
sysfs.c	btrfs: add dedicated members for start and length of a block group	2019-11-18 17:51:45 +01:00
sysfs.h	btrfs: sysfs: move helper macros to sysfs.c	2019-09-09 14:59:08 +02:00
transaction.c	btrfs: Rename btrfs_join_transaction_nolock	2019-11-18 12:46:54 +01:00
transaction.h	btrfs: Rename btrfs_join_transaction_nolock	2019-11-18 12:46:54 +01:00
tree-checker.c	btrfs: tree-checker: Check item size before reading file extent type	2019-11-18 17:51:48 +01:00
tree-checker.h	btrfs: get fs_info from eb in btrfs_check_chunk_valid	2019-04-29 19:02:39 +02:00
tree-defrag.c	btrfs: open code now trivial btrfs_set_lock_blocking	2019-02-25 14:13:27 +01:00
tree-log.c	btrfs: opencode extent_buffer_get	2019-11-18 12:46:54 +01:00
tree-log.h	btrfs: get fs_info from trans in btrfs_set_log_full_commit	2019-04-29 19:02:41 +02:00
ulist.c	btrfs: replace GPL boilerplate by SPDX -- sources	2018-04-12 16:29:51 +02:00
ulist.h	btrfs: replace GPL boilerplate by SPDX -- headers	2018-04-12 16:29:46 +02:00
uuid-tree.c	btrfs: remove unused parameter fs_info from btrfs_extend_item	2019-04-29 19:02:50 +02:00
volumes.c	btrfs: Ensure we trim ranges across block group boundary	2019-11-18 17:51:48 +01:00
volumes.h	btrfs: Remove btrfs_bio::flags member	2019-11-18 17:51:44 +01:00
xattr.c	Btrfs: fix failure to persist compression property xattr deletion on fsync	2019-06-17 16:37:17 +02:00
xattr.h	btrfs: cleanup btrfs_setxattr_trans and drop transaction parameter	2019-04-29 19:02:44 +02:00
zlib.c	btrfs: compression: inline free_workspace	2019-11-18 12:46:59 +01:00
zstd.c	btrfs: compression: inline free_workspace	2019-11-18 12:46:59 +01:00