linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: David Hildenbrand <david@redhat.com>
To: "Michael S. Tsirkin" <mst@redhat.com>,
	Alexander Duyck <alexander.duyck@gmail.com>
Cc: Nitesh Narayan Lal <nitesh@redhat.com>,
	kvm list <kvm@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	linux-mm <linux-mm@kvack.org>,
	Paolo Bonzini <pbonzini@redhat.com>,
	lcapitulino@redhat.com, pagupta@redhat.com, wei.w.wang@intel.com,
	Yang Zhang <yang.zhang.wz@gmail.com>,
	Rik van Riel <riel@surriel.com>,
	dodgen@google.com, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
	dhildenb@redhat.com, Andrea Arcangeli <aarcange@redhat.com>
Subject: Re: [RFC][Patch v9 0/6] KVM: Guest Free Page Hinting
Date: Tue, 12 Mar 2019 20:58:36 +0100	[thread overview]
Message-ID: <2b4c800a-0f62-1016-5930-797552c63281@redhat.com> (raw)
In-Reply-To: <20190307134455-mutt-send-email-mst@kernel.org>

On 07.03.19 19:46, Michael S. Tsirkin wrote:
> On Wed, Mar 06, 2019 at 10:00:05AM -0800, Alexander Duyck wrote:
>> I have been thinking about this. Instead of stealing the page couldn't
>> you simply flag it that there is a hint in progress and simply wait in
>> arch_alloc_page until the hint has been processed? The problem is in
>> stealing pages you are going to introduce false OOM issues when the
>> memory isn't available because it is being hinted on.
> 
> Can we not give them back in an OOM notifier?
> 

In the OOM notifier we might simply return "pages made available" as
long as some pages are currently being hinted. We can use an atomic_t to
track the number of requests that are sill being processed by the
hypervisor.

The larger the page granularity we have, the less likely the issue in
running into this. But yes, it might happen if the starts align.

-- 

Thanks,

David / dhildenb

      reply	other threads:[~2019-03-12 19:58 UTC|newest]

Thread overview: 84+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-06 15:50 [RFC][Patch v9 0/6] KVM: Guest Free Page Hinting Nitesh Narayan Lal
2019-03-06 15:50 ` [RFC][Patch v9 1/6] KVM: Guest free page hinting support Nitesh Narayan Lal
2019-03-06 23:43   ` Alexander Duyck
2019-03-07 19:32     ` Nitesh Narayan Lal
2019-03-06 15:50 ` [RFC][Patch v9 2/6] KVM: Enables the kernel to isolate guest free pages Nitesh Narayan Lal
2019-03-07 18:30   ` Alexander Duyck
2019-03-07 19:23     ` Nitesh Narayan Lal
2019-03-07 19:30       ` David Hildenbrand
2019-03-07 21:32         ` Alexander Duyck
2019-03-07 21:40           ` David Hildenbrand
2019-03-07 22:35             ` Alexander Duyck
2019-03-08  2:28               ` Michael S. Tsirkin
2019-03-08  2:32               ` Michael S. Tsirkin
2019-03-08 18:06                 ` Alexander Duyck
2019-03-08 18:59                   ` Michael S. Tsirkin
2019-03-08 19:10                   ` Nitesh Narayan Lal
2019-03-08 19:25                     ` Alexander Duyck
2019-03-08 19:38                       ` Nitesh Narayan Lal
2019-03-08 21:39                         ` Alexander Duyck
2019-03-12 19:46                           ` Nitesh Narayan Lal
2019-03-12 21:13                             ` Alexander Duyck
2019-03-12 21:53                               ` David Hildenbrand
2019-03-12 22:56                                 ` Alexander Duyck
2019-03-13 11:54                               ` Nitesh Narayan Lal
2019-03-13 12:17                                 ` David Hildenbrand
2019-03-13 13:08                                   ` Nitesh Narayan Lal
2019-03-13 16:37                                   ` Alexander Duyck
2019-03-13 16:39                                     ` David Hildenbrand
2019-03-13 22:54                                       ` Alexander Duyck
2019-03-13 23:18                                         ` David Hildenbrand
2019-03-06 15:50 ` [RFC][Patch v9 3/6] KVM: Enables the kernel to report isolated pages Nitesh Narayan Lal
2019-03-06 21:30   ` Alexander Duyck
2019-03-07 13:23     ` Nitesh Narayan Lal
2019-03-06 15:50 ` [RFC][Patch v9 4/6] KVM: Reporting page poisoning value to the host Nitesh Narayan Lal
2019-03-06 15:50 ` [RFC][Patch v9 5/6] KVM: Enabling guest free page hinting via static key Nitesh Narayan Lal
2019-03-06 15:50 ` [RFC][Patch v9 6/6] KVM: Adding tracepoints for guest free page hinting Nitesh Narayan Lal
2019-03-06 15:52 ` [RFC][QEMU Patch] KVM: Enable QEMU to free the pages hinted by the guest Nitesh Narayan Lal
2019-03-06 23:49   ` Alexander Duyck
2019-03-07  0:35     ` Alexander Duyck
2019-03-07 12:23       ` Nitesh Narayan Lal
2019-03-06 16:09 ` [RFC][Patch v9 0/6] KVM: Guest Free Page Hinting Michael S. Tsirkin
2019-03-06 18:07   ` Nitesh Narayan Lal
2019-03-06 18:12     ` Michael S. Tsirkin
2019-03-06 18:30       ` Nitesh Narayan Lal
2019-03-06 18:38         ` Michael S. Tsirkin
2019-03-06 18:40           ` Nitesh Narayan Lal
2019-03-06 18:43             ` Alexander Duyck
2019-03-06 18:43         ` Michael S. Tsirkin
2019-03-06 18:59           ` David Hildenbrand
2019-03-06 19:08             ` Alexander Duyck
2019-03-06 19:18               ` David Hildenbrand
2019-03-06 19:24                 ` Alexander Duyck
2019-03-06 20:31                   ` Nitesh Narayan Lal
2019-03-06 20:32             ` Michael S. Tsirkin
2019-03-06 21:40               ` David Hildenbrand
2019-03-06 22:18                 ` Michael S. Tsirkin
2019-03-06 23:12                   ` Alexander Duyck
2019-03-14 16:42       ` Nitesh Narayan Lal
2019-03-14 16:58         ` Alexander Duyck
2019-03-18 15:57           ` Nitesh Narayan Lal
2019-03-19 13:33             ` David Hildenbrand
2019-03-19 16:04               ` Nitesh Narayan Lal
2019-03-19 17:38                 ` Alexander Duyck
2019-03-19 17:59                   ` Nitesh Narayan Lal
2019-03-20 13:18                     ` Nitesh Narayan Lal
2019-03-25 14:27                       ` Nitesh Narayan Lal
2019-03-25 15:37                         ` Michael S. Tsirkin
2019-03-25 15:42                           ` Nitesh Narayan Lal
2019-03-06 18:00 ` Alexander Duyck
2019-03-06 19:07   ` Nitesh Narayan Lal
2019-03-06 22:05     ` Alexander Duyck
2019-03-07 13:09       ` Nitesh Narayan Lal
2019-03-07 18:45         ` Alexander Duyck
2019-03-07 18:53           ` Michael S. Tsirkin
2019-03-07 19:27             ` David Hildenbrand
2019-03-08  2:24               ` Michael S. Tsirkin
2019-03-08 11:53                 ` David Hildenbrand
2019-03-07 21:14             ` Alexander Duyck
2019-03-07 21:28               ` David Hildenbrand
2019-03-07 22:19                 ` Alexander Duyck
2019-03-07 19:45           ` Nitesh Narayan Lal
2019-03-07 19:49           ` David Hildenbrand
2019-03-07 18:46   ` Michael S. Tsirkin
2019-03-12 19:58     ` David Hildenbrand [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=2b4c800a-0f62-1016-5930-797552c63281@redhat.com \
    --to=david@redhat.com \
    --cc=aarcange@redhat.com \
    --cc=alexander.duyck@gmail.com \
    --cc=dhildenb@redhat.com \
    --cc=dodgen@google.com \
    --cc=konrad.wilk@oracle.com \
    --cc=kvm@vger.kernel.org \
    --cc=lcapitulino@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mst@redhat.com \
    --cc=nitesh@redhat.com \
    --cc=pagupta@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=riel@surriel.com \
    --cc=wei.w.wang@intel.com \
    --cc=yang.zhang.wz@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).