From: Chris Mason Date: Wed, 2 Sep 2009 19:11:07 +0000 (-0400) Subject: Btrfs: don't lock bits in the extent tree during writepage X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d5550c6315fe0647b7ac21a6a736bf4a42620eac;p=GitHub%2Fmt8127%2Fandroid_kernel_alcatel_ttab.git 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 --- 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: