Re: [PATCH v8 3/8] mm: Hot page tracking and promotion - pghot

[Davidlohr Bueso]

On Tue, 28 Jul 2026, Bharata B Rao wrote:

> +/**
> + * pghot_record_access() - Record page accesses from lower tier memory
> + * for the purpose of tracking page hotness and subsequent promotion.
> + *
> + * @pfn: PFN of the page
> + * @nid: Unused
> + * @src: The identifier of the sub-system that reports the access
> + * @now: Access time in jiffies
> + *
> + * Updates the frequency and time of access and marks the page as
> + * ready for migration if the frequency crosses a threshold. The pages
> + * marked for migration are migrated by kmigrated kernel thread.
> + *
> + * Return: 0 on success and -EINVAL on failure to record the access.
> + */
> +int pghot_record_access(unsigned long pfn, int nid, int src, unsigned long now)
> +{
[...]
> +}

This needs a EXPORT_SYMBOL_GPL(pghot_record_access) for any module based
sources.

Thanks,
Davidlohr