From: Filipe Manana Date: Mon, 20 Oct 2025 11:47:26 +0000 (+0100) Subject: btrfs: reduce block group critical section in btrfs_free_reserved_bytes() X-Git-Tag: v6.19-rc1~167^2~86 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8b6fa164ab59f9e3f24e627fe09a0234783e7a8b;p=thirdparty%2Fkernel%2Flinux.git btrfs: reduce block group critical section in btrfs_free_reserved_bytes() There's no need to update the space_info fields (bytes_reserved, max_extent_size, bytes_readonly, bytes_zone_unusable) while holding the block group's spinlock. So move those updates to happen after we unlock the block group (and while holding the space_info locked of course), so that all we do under the block group's critical section is to update the block group itself. Reviewed-by: Johannes Thumshirn Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba --- diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index ebd4c514c2c85..856bda9c99d95 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -3858,21 +3858,24 @@ void btrfs_free_reserved_bytes(struct btrfs_block_group *cache, u64 num_bytes, bool is_delalloc) { struct btrfs_space_info *space_info = cache->space_info; + bool bg_ro; spin_lock(&space_info->lock); spin_lock(&cache->lock); - if (cache->ro) + bg_ro = cache->ro; + cache->reserved -= num_bytes; + if (is_delalloc) + cache->delalloc_bytes -= num_bytes; + spin_unlock(&cache->lock); + + if (bg_ro) space_info->bytes_readonly += num_bytes; else if (btrfs_is_zoned(cache->fs_info)) space_info->bytes_zone_unusable += num_bytes; - cache->reserved -= num_bytes; + space_info->bytes_reserved -= num_bytes; space_info->max_extent_size = 0; - if (is_delalloc) - cache->delalloc_bytes -= num_bytes; - spin_unlock(&cache->lock); - btrfs_try_granting_tickets(space_info); spin_unlock(&space_info->lock); }