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	Mon, 08 Apr 2024 15:02:17 +0000
Date: Mon, 8 Apr 2024 16:02:17 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Christian Brauner <brauner@kernel.org>, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] fs: Add FOP_HUGE_PAGES
Message-ID: <20240408150217.GN538574@ZenIV>
References: <20240407201122.3783877-1-willy@infradead.org>
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On Sun, Apr 07, 2024 at 09:11:20PM +0100, Matthew Wilcox (Oracle) wrote:
> -static inline bool is_file_hugepages(struct file *file)
> +static inline bool is_file_hugepages(const struct file *file)
>  {
> -	if (file->f_op == &hugetlbfs_file_operations)
> -		return true;
> -
> -	return is_file_shm_hugepages(file);
> +	return file->f_op->fop_flags & FOP_HUGE_PAGES;
>  }

Extra cacheline to pull can be costly on a sufficiently hot path...