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Date: Sat, 13 Apr 2024 13:19:07 -0700
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Subject: Re: [RFC 05/10] fs/dax: Refactor wait for dax idle page
To: Alistair Popple <apopple@nvidia.com>, <linux-mm@kvack.org>
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From: John Hubbard <jhubbard@nvidia.com>
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On 4/10/24 5:57 PM, Alistair Popple wrote:
...
> diff --git a/include/linux/dax.h b/include/linux/dax.h
> index 22cd990..bced4d4 100644
> --- a/include/linux/dax.h
> +++ b/include/linux/dax.h
> @@ -212,6 +212,17 @@ int dax_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero,
>   int dax_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
>   		const struct iomap_ops *ops);
>   
> +static inline int dax_wait_page_idle(struct page *page,
> +				void (cb)(struct inode *),
> +				struct inode *inode)
> +{
> +	int ret;
> +
> +	ret = ___wait_var_event(page, page_ref_count(page) == 1,
> +				TASK_INTERRUPTIBLE, 0, 0, cb(inode));
> +	return ret;
> +}

Or just:
{
	return ___wait_var_event(page, page_ref_count(page) == 1,
			TASK_INTERRUPTIBLE, 0, 0, cb(inode));
}

...yes?


thanks,
-- 
John Hubbard
NVIDIA