remarkable-linux/fs/btrfs
Chris Mason bd681513fa Btrfs: switch the btrfs tree locks to reader/writer
The btrfs metadata btree is the source of significant
lock contention, especially in the root node.   This
commit changes our locking to use a reader/writer
lock.

The lock is built on top of rw spinlocks, and it
extends the lock tracking to remember if we have a
read lock or a write lock when we go to blocking.  Atomics
count the number of blocking readers or writers at any
given time.

It removes all of the adaptive spinning from the old code
and uses only the spinning/blocking hints inside of btrfs
to decide when it should continue spinning.

In read heavy workloads this is dramatically faster.  In write
heavy workloads we're still faster because of less contention
on the root node lock.

We suffer slightly in dbench because we schedule more often
during write locks, but all other benchmarks so far are improved.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-07-27 12:46:46 -04:00
..
acl.c Merge branch 'cleanups' of git://repo.or.cz/linux-2.6/btrfs-unstable into inode_numbers 2011-05-22 12:33:42 -04:00
async-thread.c Btrfs: don't walk around with task->state != TASK_RUNNING 2010-05-25 10:34:58 -04:00
async-thread.h Btrfs: fix deadlock on async thread startup 2009-10-05 09:44:45 -04:00
btrfs_inode.h Btrfs: fix enospc problems with delalloc 2011-07-27 12:46:44 -04:00
compat.h Btrfs: drop remaining LINUX_KERNEL_VERSION checks and compat code 2009-01-06 09:38:55 -05:00
compression.c Merge branch 'cleanups' of git://repo.or.cz/linux-2.6/btrfs-unstable into inode_numbers 2011-05-22 12:33:42 -04:00
compression.h btrfs: rename variables clashing with global function names 2011-05-02 13:57:19 +02:00
ctree.c Btrfs: switch the btrfs tree locks to reader/writer 2011-07-27 12:46:46 -04:00
ctree.h Btrfs: switch the btrfs tree locks to reader/writer 2011-07-27 12:46:46 -04:00
delayed-inode.c Btrfs: switch the btrfs tree locks to reader/writer 2011-07-27 12:46:46 -04:00
delayed-inode.h btrfs: fix inconsonant inode information 2011-06-27 11:34:27 -04:00
delayed-ref.c btrfs: remove old unused commented out code 2011-05-06 12:34:10 +02:00
delayed-ref.h btrfs: remove all unused functions 2011-05-06 12:34:03 +02:00
dir-item.c Btrfs: try to only do one btrfs_search_slot in do_setxattr 2011-07-11 09:58:45 -04:00
disk-io.c Btrfs: stop using highmem for extent_buffers 2011-07-27 12:46:45 -04:00
disk-io.h Merge branch 'cleanups' of git://repo.or.cz/linux-2.6/btrfs-unstable into inode_numbers 2011-05-22 12:33:42 -04:00
export.c Merge branch 'ino-alloc' of git://repo.or.cz/linux-btrfs-devel into inode_numbers 2011-05-21 09:27:38 -04:00
export.h NFS support for btrfs - v3 2008-09-25 11:04:06 -04:00
extent-tree.c Btrfs: switch the btrfs tree locks to reader/writer 2011-07-27 12:46:46 -04:00
extent_io.c Btrfs: switch the btrfs tree locks to reader/writer 2011-07-27 12:46:46 -04:00
extent_io.h Btrfs: switch the btrfs tree locks to reader/writer 2011-07-27 12:46:46 -04:00
extent_map.c btrfs: drop gfp parameter from alloc_extent_map 2011-05-02 13:57:21 +02:00
extent_map.h btrfs: drop gfp parameter from alloc_extent_map 2011-05-02 13:57:21 +02:00
file-item.c Btrfs: stop using highmem for extent_buffers 2011-07-27 12:46:45 -04:00
file.c Btrfs: fix enospc problems with delalloc 2011-07-27 12:46:44 -04:00
free-space-cache.c Btrfs: use find_or_create_page instead of grab_cache_page 2011-07-27 12:46:43 -04:00
free-space-cache.h btrfs: remove all unused functions 2011-05-06 12:34:03 +02:00
hash.h Btrfs: remove crc32c.h and use libcrc32c directly. 2009-06-10 11:29:53 -04:00
inode-item.c Btrfs: BUG_ON is deleted from the caller of btrfs_truncate_item & btrfs_extend_item 2011-05-23 13:24:39 -04:00
inode-map.c btrfs: add helper for fs_info->closing 2011-06-04 08:11:22 -04:00
inode-map.h Btrfs: Support reading/writing on disk free ino cache 2011-04-25 16:46:11 +08:00
inode.c Btrfs: stop using highmem for extent_buffers 2011-07-27 12:46:45 -04:00
ioctl.c Btrfs: fix enospc problems with delalloc 2011-07-27 12:46:44 -04:00
ioctl.h Btrfs: add mount -o auto_defrag 2011-05-26 17:52:15 -04:00
Kconfig btrfs: Add lzo compression support 2010-12-22 23:15:47 +08:00
locking.c Btrfs: switch the btrfs tree locks to reader/writer 2011-07-27 12:46:46 -04:00
locking.h Btrfs: switch the btrfs tree locks to reader/writer 2011-07-27 12:46:46 -04:00
lzo.c Btrfs: Avoid accessing unmapped kernel address 2011-02-16 15:37:58 -05:00
Makefile Merge branch 'for-chris' of git://git.kernel.org/pub/scm/linux/kernel/git/arne/btrfs-unstable-arne into inode_numbers 2011-05-23 06:30:52 -04:00
ordered-data.c Btrfs: add initial tracepoint support for btrfs 2011-03-28 05:37:33 -04:00
ordered-data.h btrfs: Allow to add new compression algorithm 2010-12-22 23:15:45 +08:00
orphan.c Btrfs: fixup return code for btrfs_del_orphan_item 2010-12-09 13:57:15 -05:00
print-tree.c btrfs: fix missing break in switch phrase 2011-01-28 16:40:37 -05:00
print-tree.h Btrfs: Create extent_buffer interface for large blocksizes 2008-09-25 11:03:56 -04:00
ref-cache.c btrfs: remove all unused functions 2011-05-06 12:34:03 +02:00
ref-cache.h btrfs: remove all unused functions 2011-05-06 12:34:03 +02:00
relocation.c Btrfs: use find_or_create_page instead of grab_cache_page 2011-07-27 12:46:43 -04:00
root-tree.c Merge branch 'cleanups_and_fixes' into inode_numbers 2011-05-23 14:37:47 -04:00
scrub.c btrfs: remove unneeded includes from scrub.c 2011-06-10 14:59:52 +02:00
struct-funcs.c Btrfs: stop using highmem for extent_buffers 2011-07-27 12:46:45 -04:00
super.c btrfs: add missing options displayed in mount output 2011-07-06 18:46:43 -04:00
sysfs.c btrfs: Remove unused sysfs code 2011-06-17 14:54:18 -04:00
transaction.c Btrfs: fix deadlock when throttling transactions 2011-07-27 12:46:46 -04:00
transaction.h Merge branch 'for-chris' of 2011-05-28 07:00:39 -04:00
tree-defrag.c btrfs: drop unused parameter from btrfs_release_path 2011-05-02 13:57:22 +02:00
tree-log.c Btrfs: switch the btrfs tree locks to reader/writer 2011-07-27 12:46:46 -04:00
tree-log.h btrfs: remove unused function prototypes 2011-05-04 14:01:26 +02:00
version.h Update Btrfs files for in-kernel usage 2008-09-25 15:41:59 -04:00
volumes.c Btrfs: don't panic if we get an error while balancing V2 2011-07-06 18:46:43 -04:00
volumes.h Merge branch 'cleanups_and_fixes' into inode_numbers 2011-05-23 14:37:47 -04:00
xattr.c Btrfs: try to only do one btrfs_search_slot in do_setxattr 2011-07-11 09:58:45 -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 zlib: slim down zlib_deflate() workspace when possible 2011-03-22 17:44:17 -07:00