OpenCloudOS-Kernel/fs/btrfs
Filipe David Borba Manana eb653de159 Btrfs: reduce btree node locking duration on item update
If we do a btree search with the goal of updating an existing item
without changing its size (ins_len == 0 and cow == 1), then we never
need to hold locks on upper level nodes (even when slot == 0) after we
COW their child nodes/leaves, as we won't have node splits or merges
in this scenario (that is, no key additions, removals or shifts on any
nodes or leaves).

Therefore release the locks immediately after COWing the child nodes/leaves
while navigating the btree, even if their parent slot is 0, instead of
returning a path to the caller with those nodes locked, which would get
released only when the caller releases or frees the path (or if it calls
btrfs_unlock_up_safe).

This is a common scenario, for example when updating inode items in fs
trees and block group items in the extent tree.

The following benchmarks were performed on a quad core machine with 32Gb
of ram, using a leaf/node size of 4Kb (to generate deeper fs trees more
quickly).

  sysbench --test=fileio --file-num=131072 --file-total-size=8G \
    --file-test-mode=seqwr --num-threads=512 --file-block-size=8192 \
    --max-requests=100000 --file-io-mode=sync [prepare|run]

Before this change:  49.85Mb/s (average of 5 runs)
After this change:   50.38Mb/s (average of 5 runs)

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:11 -08:00
..
tests Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
Kconfig Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2013-11-22 08:38:55 -08:00
Makefile Btrfs: add tests for btrfs_get_extent 2013-11-11 21:57:30 -05:00
acl.c btrfs: remove dead code 2014-01-28 13:19:50 -08:00
async-thread.c Btrfs: fix __btrfs_start_workers retval 2013-11-20 20:42:11 -05:00
async-thread.h Btrfs: eliminate races in worker stopping code 2013-10-04 16:02:13 -04:00
backref.c Btrfs: fix deadlock when iterating inode refs and running delayed inodes 2014-01-28 13:19:59 -08:00
backref.h Btrfs: allocate prelim_ref with a slab allocater 2013-09-01 08:16:27 -04:00
btrfs_inode.h Btrfs: introduce the delayed inode ref deletion for the single link inode 2014-01-28 13:20:09 -08:00
check-integrity.c Btrfs: fix check-integrity to look at the referenced data properly 2014-01-28 13:19:21 -08:00
check-integrity.h block: submit_bio_wait() conversions 2013-11-24 16:33:41 -07:00
compression.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
compression.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
ctree.c Btrfs: reduce btree node locking duration on item update 2014-01-28 13:20:11 -08:00
ctree.h Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
delayed-inode.c Btrfs: introduce the delayed inode ref deletion for the single link inode 2014-01-28 13:20:09 -08:00
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: skip merge part for delayed data refs 2014-01-28 13:19:23 -08:00
delayed-ref.h Btrfs: introduce a head ref rbtree 2014-01-28 13:19:22 -08:00
dev-replace.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
dev-replace.h Btrfs: add new sources for device replace code 2012-12-12 17:15:41 -05:00
dir-item.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
disk-io.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
disk-io.h Btrfs: add a sanity test for btrfs_split_item 2013-11-11 21:51:02 -05:00
export.c btrfs: remove fs/btrfs/compat.h 2013-11-11 22:03:19 -05:00
export.h NFS support for btrfs - v3 2008-09-25 11:04:06 -04:00
extent-tree.c Btrfs: stop caching thread if extent_commit_sem is contended 2014-01-28 13:20:10 -08:00
extent_io.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
extent_io.h Btrfs: move the extent buffer radix tree into the fs_info 2014-01-28 13:19:55 -08:00
extent_map.c Btrfs: fix extent_map block_len after merging 2014-01-28 13:19:51 -08:00
extent_map.h btrfs: Enclose macros with complex values within parenthesis 2013-11-11 22:12:06 -05:00
file-item.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
file.c Btrfs: fix use of uninitialized err variable 2014-01-28 13:19:57 -08:00
free-space-cache.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
free-space-cache.h Btrfs: remove path arg from btrfs_truncate_free_space_cache 2013-11-11 21:51:33 -05:00
hash.h btrfs: extended inode refs 2012-10-09 09:14:45 -04:00
inode-item.c btrfs: cleanup: removed unused 'btrfs_get_inode_ref_index' 2014-01-28 13:19:39 -08:00
inode-map.c btrfs: Use WARN_ON()'s return value in place of WARN_ON(1) 2013-11-11 22:11:53 -05:00
inode-map.h Btrfs: Support reading/writing on disk free ino cache 2011-04-25 16:46:11 +08:00
inode.c Btrfs: reduce btree node locking duration on item update 2014-01-28 13:20:11 -08:00
ioctl.c fs/btrfs: Integer overflow in btrfs_ioctl_resize() 2014-01-28 13:20:11 -08:00
locking.c btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
locking.h Btrfs: remove btrfs_try_spin_lock 2013-03-14 14:57:10 -04:00
lzo.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
math.h Btrfs: cleanup duplicated division functions 2012-12-11 13:31:30 -05:00
ordered-data.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
ordered-data.h Btrfs: don't wait for the completion of all the ordered extents 2013-11-11 22:13:44 -05:00
orphan.c btrfs: expand btrfs_find_item() to include find_orphan_item functionality 2014-01-28 13:19:37 -08:00
print-tree.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
print-tree.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
qgroup.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
raid56.c btrfs: remove fs/btrfs/compat.h 2013-11-11 22:03:19 -05:00
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: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
relocation.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
root-tree.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
scrub.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
send.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
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: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
sysfs.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
sysfs.h btrfs: publish allocation data in sysfs 2014-01-28 13:19:29 -08:00
transaction.c Btrfs: remove btrfs_end_transaction_dmeta() 2014-01-28 13:20:08 -08:00
transaction.h Btrfs: remove btrfs_end_transaction_dmeta() 2014-01-28 13:20:08 -08:00
tree-defrag.c Btrfs: cleanup dead code of defragment 2013-11-11 21:59:45 -05:00
tree-log.c btrfs: expand btrfs_find_item() to include find_orphan_item functionality 2014-01-28 13:19:37 -08:00
tree-log.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
ulist.c Btrfs: fix crash regarding to ulist_add_merge 2013-07-02 11:50:59 -04:00
ulist.h Btrfs: add a rb_tree to improve performance of ulist search 2013-05-06 15:54:44 -04:00
uuid-tree.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
volumes.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00
volumes.h btrfs: Pack struct btrfs_device 2013-11-11 22:11:26 -05:00
xattr.c btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
xattr.h fs/vfs/security: pass last path component to LSM on inode creation 2011-02-01 11:12:29 -05:00
zlib.c Btrfs: convert printk to btrfs_ and fix BTRFS prefix 2014-01-28 13:20:05 -08:00