Re: [PATCH v2 3/9] xen/balloon: Share common memory reservation routines

[Oleksandr Andrushchenko <andr2000@gmail.com>]

On 06/07/2018 12:09 AM, Boris Ostrovsky wrote:
> On 06/06/2018 03:24 AM, Oleksandr Andrushchenko wrote:
>> On 06/04/2018 07:37 PM, Boris Ostrovsky wrote:
>>> On 06/01/2018 07:41 AM, Oleksandr Andrushchenko wrote:
>>>> diff --git a/include/xen/mem-reservation.h
>>>> b/include/xen/mem-reservation.h
>>>> new file mode 100644
>>>> index 000000000000..a727d65a1e61
>>>> --- /dev/null
>>>> +++ b/include/xen/mem-reservation.h
>>>> @@ -0,0 +1,65 @@
>>>> +/* SPDX-License-Identifier: GPL-2.0 */
>>>> +
>>>> +/*
>>>> + * Xen memory reservation utilities.
>>>> + *
>>>> + * Copyright (c) 2003, B Dragovic
>>>> + * Copyright (c) 2003-2004, M Williamson, K Fraser
>>>> + * Copyright (c) 2005 Dan M. Smith, IBM Corporation
>>>> + * Copyright (c) 2010 Daniel Kiper
>>>> + * Copyright (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc.
>>>> + */
>>>> +
>>>> +#ifndef _XENMEM_RESERVATION_H
>>>> +#define _XENMEM_RESERVATION_H
>>>> +
>>>> +#include <linux/kernel.h>
>>>> +#include <linux/slab.h>
>>>> +
>>>> +#include <asm/xen/hypercall.h>
>>>> +#include <asm/tlb.h>
>>>> +
>>>> +#include <xen/interface/memory.h>
>>>> +#include <xen/page.h>
>>>> +
>>>> +#ifdef CONFIG_XEN_SCRUB_PAGES
>>>> +void xenmem_reservation_scrub_page(struct page *page);
>>>> +#else
>>>> +static inline void xenmem_reservation_scrub_page(struct page *page)
>>>> +{
>>>> +}
>>>> +#endif
>>> Given that this is a wrapper around a single call I'd prefer
>>>
>>> inline void xenmem_reservation_scrub_page(struct page *page)
>>> {
>>> #ifdef CONFIG_XEN_SCRUB_PAGES
>>>       clear_highpage(page);
>>> #endif
>>> }
>> Unfortunately this can't be done because of
>> EXPORT_SYMBOL_GPL(xenmem_reservation_scrub_page);
>> which is obviously cannot be used for static inline functions.
>
>
> Why do you need to export it? It's an inline defined in the header file.
> Just like clear_highpage().
You are perfectly right, will change as you suggest
>
> -boris
Thank you,
Oleksandr
>> So, I'll keep it as is.
>>>
>>> -boris
>>>
>>>
>> Thank you,
>> Oleksandr