From: Filipe Manana <fdmanana@suse.com>
Date: Mon, 20 Oct 2025 14:53:01 +0000 (+0100)
Subject: btrfs: reduce block group critical section in unpin_extent_range()
X-Git-Tag: v6.19-rc1~167^2~79
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=36574363b75c6adf4642dc5f33b2a33870c8da3c;p=thirdparty%2Fkernel%2Flinux.git

btrfs: reduce block group critical section in unpin_extent_range()

There's no need to update the bytes_pinned, bytes_readonly and
max_extent_size fields of the space_info while inside the critical section
delimited by the block group's lock. So move that out of the block group's
critical section, but sill inside the space_info's critical section.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
---

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 36963b4a6303f..d839d8d324125 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2747,13 +2747,12 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 	struct btrfs_free_cluster *cluster = NULL;
 	u64 total_unpinned = 0;
 	u64 empty_cluster = 0;
-	bool readonly;
 	int ret = 0;
 
 	while (start <= end) {
 		u64 len;
+		bool readonly;
 
-		readonly = false;
 		if (!cache ||
 		    start >= cache->start + cache->length) {
 			if (cache)
@@ -2797,20 +2796,21 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info,
 
 		spin_lock(&space_info->lock);
 		spin_lock(&cache->lock);
+		readonly = cache->ro;
 		cache->pinned -= len;
+		spin_unlock(&cache->lock);
+
 		btrfs_space_info_update_bytes_pinned(space_info, -len);
 		space_info->max_extent_size = 0;
-		if (cache->ro) {
+
+		if (readonly) {
 			space_info->bytes_readonly += len;
-			readonly = true;
 		} else if (btrfs_is_zoned(fs_info)) {
 			/* Need reset before reusing in a zoned block group */
 			btrfs_space_info_update_bytes_zone_unusable(space_info, len);
-			readonly = true;
-		}
-		spin_unlock(&cache->lock);
-		if (!readonly && return_free_space)
+		} else if (return_free_space) {
 			btrfs_return_free_space(space_info, len);
+		}
 		spin_unlock(&space_info->lock);
 	}