Re: [PATCH] btrfs: move async csum generation out of experimental features

[David Sterba <dsterba@suse.cz>]

On Thu, Sep 03, 2026 at 06:09:41PM +0930, Qu Wenruo wrote:
> -static bool should_async_write(struct btrfs_bio *bbio)
> -{
> -	struct btrfs_fs_info *fs_info = bbio->inode->root->fs_info;
> -	bool auto_csum_mode = true;
> -
> -#ifdef CONFIG_BTRFS_EXPERIMENTAL
> -	/*
> -	 * Write bios will calculate checksum and submit bio at the same time.
> -	 * Unless explicitly required don't offload serial csum calculate and bio
> -	 * submit into a workqueue.
> -	 */
> -	return false;
> -#endif
> -
> -	/* Submit synchronously if the checksum implementation is fast. */
> -	if (auto_csum_mode && test_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags))

The fast csum implementation is not used anymore, so the
BTRFS_FS_CSUM_IMPL_FAST definition and related code can be deleted.

> -		return false;
> -
> -	/*
> -	 * Try to defer the submission to a workqueue to parallelize the
> -	 * checksum calculation unless the I/O is issued synchronously.
> -	 */
> -	if (op_is_sync(bbio->bio.bi_opf))
> -		return false;
> -
> -	/* Zoned devices require I/O to be submitted in order. */
> -	if ((bbio->bio.bi_opf & REQ_META) && btrfs_is_zoned(fs_info))
> -		return false;
> -
> -	return true;
> -}