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Date:   Thu, 8 Jun 2023 05:15:43 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Qu Wenruo <wqu@suse.com>
Cc:     linux-btrfs@vger.kernel.org, fstests@vger.kernel.org
Subject: Re: [PATCH RFC] common/btrfs: use _scratch_cycle_mount to ensure all
 page caches are dropped
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On Thu, Jun 08, 2023 at 07:48:36PM +0800, Qu Wenruo wrote:
>  	echo 3 > /proc/sys/vm/drop_caches
> +	# Above drop_caches doesn't seem to drop every pages on aarch64 with
> +	# 64K page size.
> +	# So here as a workaround, cycle mount the SCRATCH_MNT to ensure
> +	# the cache are dropped.
> +	_scratch_cycle_mount

The _scratch_cycle_mount looks ok to me, but if we do that, there is
really no point in doing the drop_caches as well.