diff mbox series

[3/5] btrfs: remove i_size restriction at try_release_extent_mapping()

Message ID c9c03b39687c2cc599725c508b354e40898d9844.1713302470.git.fdmanana@suse.com (mailing list archive)
State New
Headers show
Series btrfs: cleanups and improvements around extent map release | expand

Commit Message

Filipe Manana April 17, 2024, 11:03 a.m. UTC 
From: Filipe Manana <fdmanana@suse.com>

Currently we don't attempt to release extent maps if the inode has an
i_size that is not greater than 16M. This condition was added way back
in 2008 by commit 70dec8079d78 ("Btrfs: extent_io and extent_state
optimizations"), without any explanation about it. A quick chat with
Chris on slack revealed that the goal was probably to release the extent
maps for small files only when closing the inode. This however can be
harmful in case we have tons of such files being kept open for very long
periods of time, since we will consume more and more pages for extent
maps.

So remove the condition.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
---
 fs/btrfs/extent_io.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

Comments

Johannes Thumshirn April 17, 2024, 11:23 a.m. UTC | #1 
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>

I wonder if we should eventually backport this to stable, as it could 
mitigate OOM situations w/o the em shrinker?
diff mbox series

Patch

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index f689c53553e3..ff9132b897e3 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2402,8 +2402,7 @@  int try_release_extent_mapping(struct page *page, gfp_t mask)
 	struct extent_io_tree *io_tree = &inode->io_tree;
 	struct extent_map_tree *extent_tree = &inode->extent_tree;
 
-	if (gfpflags_allow_blocking(mask) &&
-	    page->mapping->host->i_size > SZ_16M) {
+	if (gfpflags_allow_blocking(mask)) {
 		u64 len;
 		while (start <= end) {
 			const u64 cur_gen = btrfs_get_fs_generation(inode->root->fs_info);