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Date:   Mon, 13 Jul 2020 17:41:45 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Chris Down <chris@chrisdown.name>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Hugh Dickins <hughd@google.com>,
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        Tejun Heo <tj@kernel.org>, linux-mm@kvack.org,
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Subject: Re: [PATCH v6 1/2] tmpfs: Per-superblock i_ino support
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On Mon, Jul 13, 2020 at 05:15:39PM +0100, Chris Down wrote:
> +#define SHMEM_INO_BATCH 1024U
...
> +		if (unlikely((ino & ~SHMEM_INO_BATCH) == 0)) {

I don't think that works.  I think you meant to write ~(SHMEM_INO_BATCH - 1).
Or just ino % SHMEM_INO_BATCH which works even for non-power-of-two.