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

Boris Ostrovsky
2018-06-06T21:09:50Z

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().

-boris

> So, I'll keep it as is.
>>
>>
>> -boris
>>
>>
> Thank you,
> Oleksandr