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Btrfs: cache the extent state everywhere we possibly can V2

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This patch just goes through and fixes everybody that does

lock_extent()
blah
unlock_extent()

to use

lock_extent_bits()
blah
unlock_extent_cached()

and pass around a extent_state so we only have to do the searches once per
function.  This gives me about a 3 mb/s boots on my random write test.  I have
not converted some things, like the relocation and ioctl's, since they aren't
heavily used and the relocation stuff is in the middle of being re-written.  I
also changed the clear_extent_bit() to only unset the cached state if we are
clearing EXTENT_LOCKED and related stuff, so we can do things like this

lock_extent_bits()
clear delalloc bits
unlock_extent_cached()

without losing our cached state.  I tested this thoroughly and turned on
LEAK_DEBUG to make sure we weren't leaking extent states, everything worked out
fine.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Josef Bacik
2010-02-03 19:33:23 +00:00
committed by Chris Mason
parent 5a1a3df1f6
commit 2ac55d41b5
9 changed files with 148 additions and 90 deletions
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15
fs/btrfs/disk-io.c
View File

@@ -263,13 +263,15 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
static int verify_parent_transid(struct extent_io_tree *io_tree,
struct extent_buffer *eb, u64 parent_transid)
{
struct extent_state *cached_state = NULL;
int ret;
if (!parent_transid || btrfs_header_generation(eb) == parent_transid)
return 0;
lock_extent(io_tree, eb->start, eb->start + eb->len - 1, GFP_NOFS);
if (extent_buffer_uptodate(io_tree, eb) &&
lock_extent_bits(io_tree, eb->start, eb->start + eb->len - 1,
0, &cached_state, GFP_NOFS);
if (extent_buffer_uptodate(io_tree, eb, cached_state) &&
btrfs_header_generation(eb) == parent_transid) {
ret = 0;
goto out;
@@ -282,10 +284,10 @@ static int verify_parent_transid(struct extent_io_tree *io_tree,
(unsigned long long)btrfs_header_generation(eb));
}
ret = 1;
clear_extent_buffer_uptodate(io_tree, eb);
clear_extent_buffer_uptodate(io_tree, eb, &cached_state);
out:
unlock_extent(io_tree, eb->start, eb->start + eb->len - 1,
GFP_NOFS);
unlock_extent_cached(io_tree, eb->start, eb->start + eb->len - 1,
&cached_state, GFP_NOFS);
return ret;
}
@@ -2497,7 +2499,8 @@ int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid)
int ret;
struct inode *btree_inode = buf->first_page->mapping->host;
ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf);
ret = extent_buffer_uptodate(&BTRFS_I(btree_inode)->io_tree, buf,
NULL);
if (!ret)
return ret;