From d5550c6315fe0647b7ac21a6a736bf4a42620eac Mon Sep 17 00:00:00 2001
From: Chris Mason <chris.mason@oracle.com>
Date: Wed, 2 Sep 2009 15:11:07 -0400
Subject: [PATCH] Btrfs: don't lock bits in the extent tree during writepage
At writepage time, we have the page locked and we have the
extent_map entry for this extent pinned in the extent_map tree.
So, the page can't go away and its mapping can't change.
There is no need for the extra extent_state lock bits during writepage.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
---
fs/btrfs/extent_io.c | 21 ---------------------
1 file changed, 21 deletions(-)
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index c7a5e860fe21..04fafc3cffc0 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2219,16 +2219,10 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
goto done_unlocked;
}
}
- lock_extent_bits(tree, start, page_end, 0, &cached_state, GFP_NOFS);
-
- unlock_start = start;
-
if (tree->ops && tree->ops->writepage_start_hook) {
ret = tree->ops->writepage_start_hook(page, start,
page_end);
if (ret == -EAGAIN) {
- unlock_extent_cached(tree, start, page_end,
- &cached_state, GFP_NOFS);
redirty_page_for_writepage(wbc, page);
update_nr_written(page, wbc, nr_written);
unlock_page(page);
@@ -2244,13 +2238,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
update_nr_written(page, wbc, nr_written + 1);
end = page_end;
- if (test_range_bit(tree, start, page_end, EXTENT_DELALLOC, 0))
- printk(KERN_ERR "btrfs delalloc bits after lock_extent\n");
-
if (last_byte <= start) {
- clear_extent_bit(tree, start, page_end,
- EXTENT_LOCKED | EXTENT_DIRTY,
- 1, 0, NULL, GFP_NOFS);
if (tree->ops && tree->ops->writepage_end_io_hook)
tree->ops->writepage_end_io_hook(page, start,
page_end, NULL, 1);
@@ -2262,8 +2250,6 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
while (cur <= end) {
if (cur >= last_byte) {
- unlock_extent_cached(tree, unlock_start, page_end,
- &cached_state, GFP_NOFS);
if (tree->ops && tree->ops->writepage_end_io_hook)
tree->ops->writepage_end_io_hook(page, cur,
page_end, NULL, 1);
@@ -2295,10 +2281,6 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc,
*/
if (compressed || block_start == EXTENT_MAP_HOLE ||
block_start == EXTENT_MAP_INLINE) {
- unlock_extent_cached(tree, unlock_start,
- cur + iosize - 1, &cached_state,
- GFP_NOFS);
-
/*
* end_io notification does not happen here for
* compressed extents
@@ -2366,9 +2348,6 @@ done:
set_page_writeback(page);
end_page_writeback(page);
}
- if (unlock_start <= page_end)
- unlock_extent_cached(tree, unlock_start, page_end,
- &cached_state, GFP_NOFS);
unlock_page(page);
done_unlocked: