[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <8735a3a0-e1aa-e64d-af67-5cca3ae2c529@redhat.com>
Date: Tue, 13 Aug 2019 12:44:35 +0200
From: David Hildenbrand <david@...hat.com>
To: Nitesh Narayan Lal <nitesh@...hat.com>,
Alexander Duyck <alexander.duyck@...il.com>
Cc: kvm list <kvm@...r.kernel.org>,
LKML <linux-kernel@...r.kernel.org>,
linux-mm <linux-mm@...ck.org>, virtio-dev@...ts.oasis-open.org,
Paolo Bonzini <pbonzini@...hat.com>, lcapitulino@...hat.com,
pagupta@...hat.com, wei.w.wang@...el.com,
Yang Zhang <yang.zhang.wz@...il.com>,
Rik van Riel <riel@...riel.com>,
"Michael S. Tsirkin" <mst@...hat.com>, dodgen@...gle.com,
Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>,
dhildenb@...hat.com, Andrea Arcangeli <aarcange@...hat.com>,
john.starks@...rosoft.com, Dave Hansen <dave.hansen@...el.com>,
Michal Hocko <mhocko@...e.com>, cohuck@...hat.com
Subject: Re: [RFC][Patch v12 1/2] mm: page_reporting: core infrastructure
On 13.08.19 12:42, Nitesh Narayan Lal wrote:
>
> On 8/13/19 6:34 AM, David Hildenbrand wrote:
>>>>>> +static int process_free_page(struct page *page,
>>>>>> + struct page_reporting_config *phconf, int count)
>>>>>> +{
>>>>>> + int mt, order, ret = 0;
> [...]
>>>>>> +/**
>>>>>> + * zone_reporting_init - For each zone initializes the page reporting fields
>>>>>> + * and allocates the respective bitmap.
>>>>>> + *
>>>>>> + * This function returns 0 on successful initialization, -ENOMEM otherwise.
>>>>>> + */
>>>>>> +static int zone_reporting_init(void)
>>>>>> +{
>>>>>> + struct zone *zone;
>>>>>> + int ret;
>>>>>> +
>>>>>> + for_each_populated_zone(zone) {
>>>>>> +#ifdef CONFIG_ZONE_DEVICE
>>>>>> + /* we can not report pages which are not in the buddy */
>>>>>> + if (zone_idx(zone) == ZONE_DEVICE)
>>>>>> + continue;
>>>>>> +#endif
>>>>> I'm pretty sure this isn't needed since I don't think the ZONE_DEVICE
>>>>> zone will be considered "populated".
>>>>>
>>>> I think you are right (although it's confusing, we will have present
>>>> sections part of a zone but the zone has no present_pages - screams like
>>>> a re factoring - leftover from ZONE_DEVICE introduction).
>>>
>>> I think in that case it is safe to have this check here.
>>> What do you guys suggest?
>> If it's not needed, I'd say drop it (eventually add a comment).
>
>
> Comment to mention that we do not expect a zone with non-buddy page to be
> initialized here?
Something along these lines, or something like
/* ZONE_DEVICE is never considered populated */
--
Thanks,
David / dhildenb
Powered by blists - more mailing lists