linux_dsm_epyc7002/fs/btrfs
Qu Wenruo e6c4efd87a btrfs: Fix and enhance merge_extent_mapping() to insert best fitted extent map
The following commit enhanced the merge_extent_mapping() to reduce
fragment in extent map tree, but it can't handle case which existing
lies before map_start:
51f39 btrfs: Use right extent length when inserting overlap extent map.

[BUG]
When existing extent map's start is before map_start,
the em->len will be minus, which will corrupt the extent map and fail to
insert the new extent map.
This will happen when someone get a large extent map, but when it is
going to insert it into extent map tree, some one has already commit
some write and split the huge extent into small parts.

[REPRODUCER]
It is very easy to tiger using filebench with randomrw personality.
It is about 100% to reproduce when using 8G preallocated file in 60s
randonrw test.

[FIX]
This patch can now handle any existing extent position.
Since it does not directly use existing->start, now it will find the
previous and next extent around map_start.
So the old existing->start < map_start bug will never happen again.

[ENHANCE]
This patch will insert the best fitted extent map into extent map tree,
other than the oldest [map_start, map_start + sectorsize) or the
relatively newer but not perfect [map_start, existing->start).

The patch will first search existing extent that does not intersects with
the desired map range [map_start, map_start + len).
The existing extent will be either before or behind map_start, and based
on the existing extent, we can find out the previous and next extent
around map_start.

So the best fitted extent would be [prev->end, next->start).
For prev or next is not found, em->start would be prev->end and em->end
wold be next->start.

With this patch, the fragment in extent map tree should be reduced much
more than the 51f39 commit and reduce an unneeded extent map tree search.

Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-18 07:14:46 -07:00
..
tests Btrfs: improve free space cache management and space allocation 2014-09-17 13:38:13 -07:00
acl.c btrfs: remove useless ACL check 2014-06-09 17:20:42 -07:00
async-thread.c Btrfs: implement repair function when direct read fails 2014-09-17 13:39:01 -07:00
async-thread.h Btrfs: implement repair function when direct read fails 2014-09-17 13:39:01 -07:00
backref.c Btrfs: make fiemap not blow when you have lots of snapshots 2014-09-17 13:38:24 -07:00
backref.h Btrfs: make fiemap not blow when you have lots of snapshots 2014-09-17 13:38:24 -07:00
btrfs_inode.h Btrfs: implement repair function when direct read fails 2014-09-17 13:39:01 -07:00
check-integrity.c Btrfs: fix wrong disk size when writing super blocks 2014-09-17 13:38:33 -07:00
check-integrity.h block: submit_bio_wait() conversions 2013-11-24 16:33:41 -07:00
compression.c btrfs: use DIV_ROUND_UP instead of open-coded variants 2014-09-17 13:37:17 -07:00
compression.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
ctree.c Btrfs: make btrfs_search_forward return with nodes unlocked 2014-09-17 13:38:02 -07:00
ctree.h Btrfs: implement repair function when direct read fails 2014-09-17 13:39:01 -07:00
delayed-inode.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
delayed-inode.h Btrfs: introduce the delayed inode ref deletion for the single link inode 2014-01-28 13:20:09 -08:00
delayed-ref.c Btrfs: rework qgroup accounting 2014-06-09 17:20:48 -07:00
delayed-ref.h Btrfs: rework qgroup accounting 2014-06-09 17:20:48 -07:00
dev-replace.c Btrfs: make the logic of source device removing more clear 2014-09-17 13:38:46 -07:00
dev-replace.h Btrfs: add new sources for device replace code 2012-12-12 17:15:41 -05:00
dir-item.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
disk-io.c Btrfs: implement repair function when direct read fails 2014-09-17 13:39:01 -07:00
disk-io.h Btrfs: implement repair function when direct read fails 2014-09-17 13:39:01 -07:00
export.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
export.h NFS support for btrfs - v3 2008-09-25 11:04:06 -04:00
extent_io.c Btrfs: cleanup the read failure record after write or when the inode is freeing 2014-09-17 13:39:02 -07:00
extent_io.h Btrfs: cleanup the read failure record after write or when the inode is freeing 2014-09-17 13:39:02 -07:00
extent_map.c Btrfs: fix NULL pointer crash when running balance and scrub concurrently 2014-06-19 14:20:55 -07:00
extent_map.h Btrfs: fix NULL pointer crash when running balance and scrub concurrently 2014-06-19 14:20:55 -07:00
extent-tree.c Btrfs: Fix misuse of chunk mutex 2014-09-17 13:38:42 -07:00
file-item.c Btrfs: load checksum data once when submitting a direct read io 2014-09-17 13:38:50 -07:00
file.c Btrfs: fix up bounds checking in lseek 2014-09-17 13:46:30 -07:00
free-space-cache.c Btrfs: improve free space cache management and space allocation 2014-09-17 13:38:13 -07:00
free-space-cache.h Btrfs: remove path arg from btrfs_truncate_free_space_cache 2013-11-11 21:51:33 -05:00
hash.c btrfs: use PTR_ERR_OR_ZERO 2014-09-17 13:37:29 -07:00
hash.h Btrfs: fix btrfs boot when compiled as built-in 2014-01-28 13:20:31 -08:00
inode-item.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
inode-map.c btrfs: cleanup ino cache members of btrfs_root 2014-09-17 13:37:09 -07:00
inode-map.h Btrfs: Support reading/writing on disk free ino cache 2011-04-25 16:46:11 +08:00
inode.c btrfs: Fix and enhance merge_extent_mapping() to insert best fitted extent map 2014-09-18 07:14:46 -07:00
ioctl.c Btrfs: fix unprotected device's variants on 32bits machine 2014-09-17 13:38:38 -07:00
Kconfig Btrfs: fix btrfs boot when compiled as built-in 2014-01-28 13:20:31 -08:00
locking.c Btrfs: fix deadlocks with trylock on tree nodes 2014-06-19 14:19:55 -07:00
locking.h Btrfs: remove btrfs_try_spin_lock 2013-03-14 14:57:10 -04:00
lzo.c btrfs: use DIV_ROUND_UP instead of open-coded variants 2014-09-17 13:37:17 -07:00
Makefile Btrfs: add sanity tests for new qgroup accounting code 2014-06-09 17:20:49 -07:00
math.h Btrfs: cleanup duplicated division functions 2012-12-11 13:31:30 -05:00
ordered-data.c Btrfs: fix task hang under heavy compressed write 2014-08-24 07:17:02 -07:00
ordered-data.h btrfs: disable strict file flushes for renames and truncates 2014-08-15 07:43:42 -07:00
orphan.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
print-tree.c btrfs: use nodesize everywhere, kill leafsize 2014-09-17 13:37:14 -07:00
print-tree.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
props.c Btrfs: add support for inode properties 2014-01-28 13:20:24 -08:00
props.h Btrfs: add support for inode properties 2014-01-28 13:20:24 -08:00
qgroup.c btrfs: don't go readonly on existing qgroup items 2014-09-17 13:38:19 -07:00
qgroup.h btrfs: qgroup: account shared subtrees during snapshot delete 2014-08-15 07:43:14 -07:00
raid56.c btrfs: use DIV_ROUND_UP instead of open-coded variants 2014-09-17 13:37:17 -07:00
raid56.h Btrfs: RAID5 and RAID6 2013-02-01 14:24:23 -05:00
rcu-string.h Btrfs: use rcu to protect device->name 2012-06-14 21:29:16 -04:00
reada.c btrfs: use nodesize everywhere, kill leafsize 2014-09-17 13:37:14 -07:00
relocation.c btrfs: use nodesize everywhere, kill leafsize 2014-09-17 13:37:14 -07:00
root-tree.c Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root 2014-06-09 17:20:40 -07:00
scrub.c Btrfs: modify clean_io_failure and make it suit direct io 2014-09-17 13:38:59 -07:00
send.c Btrfs: send, lower mem requirements for processing xattrs 2014-09-17 13:38:16 -07:00
send.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
struct-funcs.c Btrfs: rewrite BTRFS_SETGET_FUNCS 2012-07-23 16:28:06 -04:00
super.c Btrfs: fix unprotected device list access when getting the fs information 2014-09-17 13:38:41 -07:00
sysfs.c btrfs: sysfs label interface should check for read only FS 2014-09-17 13:38:01 -07:00
sysfs.h btrfs: code optimize: BTRFS_ATTR_RW could set the mode 2014-09-17 13:37:59 -07:00
transaction.c Btrfs: fix wrong device bytes_used in the super block 2014-09-17 13:38:34 -07:00
transaction.h btrfs: disable strict file flushes for renames and truncates 2014-08-15 07:43:42 -07:00
tree-defrag.c Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root 2014-06-09 17:20:40 -07:00
tree-log.c Btrfs: fix directory recovery from fsync log 2014-09-17 13:38:27 -07:00
tree-log.h Btrfs: fix fsync data loss after a ranged fsync 2014-09-08 13:56:43 -07:00
ulist.c Btrfs: do not export ulist functions 2014-01-29 07:06:27 -08:00
ulist.h Btrfs: Fix memory corruption by ulist_add_merge() on 32bit arch 2014-08-15 07:43:19 -07:00
uuid-tree.c Btrfs: make btrfs_search_forward return with nodes unlocked 2014-09-17 13:38:02 -07:00
volumes.c Btrfs: Set real mirror number for read operation on RAID0/5/6 2014-09-17 13:39:00 -07:00
volumes.h Btrfs: do file data check by sub-bio's self 2014-09-17 13:38:53 -07:00
xattr.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
xattr.h btrfs: use generic posix ACL infrastructure 2014-01-25 23:58:18 -05:00
zlib.c btrfs compression: merge inflate and deflate z_streams 2014-09-17 13:37:33 -07:00