public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Marcelo Tosatti <mtosatti@redhat.com>
To: Avi Kivity <avi@redhat.com>
Cc: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>,
	LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
Subject: Re: [PATCH 11/11] KVM: MMU: improve write flooding detected
Date: Thu, 25 Aug 2011 10:21:11 -0300	[thread overview]
Message-ID: <20110825132110.GA4384@amt.cnet> (raw)
In-Reply-To: <4E55D2A2.7050808@redhat.com>

On Thu, Aug 25, 2011 at 07:42:10AM +0300, Avi Kivity wrote:
> On 08/25/2011 05:04 AM, Marcelo Tosatti wrote:
> >>
> >>  It could increase the flood count independently of the accessed bit of
> >>  the spte being updated, zapping after 3 attempts as it is now.
> >>
> >>  But additionally reset the flood count if the gpte appears to be valid
> >>  (points to an existant gfn if the present bit is set, or if its zeroed).
> >
> >Well not zero, as thats a common pattern for non ptes.
> >
> 
> On 32-bit with 4GB RAM, practically anything is a valid gpte.

The following could be required to consider a valid gpte, for write
flood detection purposes:

- Must be present.
- PageCacheDisable must be unset.
- PageWriteThrough must be unset.



  reply	other threads:[~2011-08-25 13:47 UTC|newest]

Thread overview: 41+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-08-16  6:40 [PATCH 01/11] KVM: MMU: avoid pte_list_desc running out in kvm_mmu_pte_write Xiao Guangrong
2011-08-16  6:41 ` [PATCH 02/11] KVM: x86: tag the instructions which are used to write page table Xiao Guangrong
2011-08-22 14:32   ` Marcelo Tosatti
2011-08-22 14:36     ` Avi Kivity
2011-08-16  6:42 ` [PATCH 03/11] KVM: x86: retry non-page-table writing instruction Xiao Guangrong
2011-08-22 19:59   ` Marcelo Tosatti
2011-08-22 20:21     ` Xiao Guangrong
2011-08-22 20:42       ` Marcelo Tosatti
2011-08-16  6:42 ` [PATCH 04/11] KVM: x86: cleanup port-in/port-out emulated Xiao Guangrong
2011-08-16  6:43 ` [PATCH 05/11] KVM: MMU: do not mark access bit on pte write path Xiao Guangrong
2011-08-16  6:44 ` [PATCH 06/11] KVM: MMU: cleanup FNAME(invlpg) Xiao Guangrong
2011-08-16  6:44 ` [PATCH 07/11] KVM: MMU: fast prefetch spte on invlpg path Xiao Guangrong
2011-08-22 22:28   ` Marcelo Tosatti
2011-08-23  1:50     ` Xiao Guangrong
2011-08-16  6:45 ` [PATCH 08/11] KVM: MMU: remove unnecessary kvm_mmu_free_some_pages Xiao Guangrong
2011-08-16  6:45 ` [PATCH 09/11] KVM: MMU: split kvm_mmu_pte_write function Xiao Guangrong
2011-08-16  6:46 ` [PATCH 10/11] KVM: MMU: fix detecting misaligned accessed Xiao Guangrong
2011-08-16  6:46 ` [PATCH 11/11] KVM: MMU: improve write flooding detected Xiao Guangrong
2011-08-23  8:00   ` Marcelo Tosatti
2011-08-23 10:55     ` Xiao Guangrong
2011-08-23 12:38       ` Marcelo Tosatti
2011-08-23 16:32         ` Xiao Guangrong
2011-08-23 19:09           ` Marcelo Tosatti
2011-08-23 20:16             ` Xiao Guangrong
2011-08-24 20:05               ` Marcelo Tosatti
2011-08-25  2:04                 ` Marcelo Tosatti
2011-08-25  4:42                   ` Avi Kivity
2011-08-25 13:21                     ` Marcelo Tosatti [this message]
2011-08-25 14:06                       ` Avi Kivity
2011-08-25 14:07                         ` Avi Kivity
2011-08-25  7:40                   ` Xiao Guangrong
2011-08-25  7:57             ` Xiao Guangrong
2011-08-25 13:47               ` Marcelo Tosatti
2011-08-26  3:18                 ` Xiao Guangrong
2011-08-26 10:53                   ` Marcelo Tosatti
2011-08-26 14:24                     ` Xiao Guangrong
  -- strict thread matches above, loose matches on Subject: below --
2011-07-26 11:24 [PATCH 0/11] KVM: x86: optimize for guest page written Xiao Guangrong
2011-07-26 11:32 ` [PATCH 11/11] KVM: MMU: improve write flooding detected Xiao Guangrong
2011-07-27  9:23   ` Avi Kivity
2011-07-27 10:20     ` Xiao Guangrong
2011-07-27 11:08       ` Avi Kivity
2011-07-28  2:43         ` Xiao Guangrong

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=20110825132110.GA4384@amt.cnet \
    --to=mtosatti@redhat.com \
    --cc=avi@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=xiaoguangrong@cn.fujitsu.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