From: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
To: Avi Kivity <avi@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>,
LKML <linux-kernel@vger.kernel.org>, KVM <kvm@vger.kernel.org>
Subject: Re: [PATCH 03/11] KVM: x86: fast emulate repeat string write instructions
Date: Wed, 27 Jul 2011 17:37:51 +0800 [thread overview]
Message-ID: <4E2FDC6F.4050006@cn.fujitsu.com> (raw)
In-Reply-To: <4E2FD499.2070308@redhat.com>
On 07/27/2011 05:04 PM, Avi Kivity wrote:
> On 07/26/2011 02:26 PM, Xiao Guangrong wrote:
>> We usually use repeat string instructions to clear the page, for example,
>> we call memset to clear a page table, stosb is used in this function, and
>> repeated for 1024 times, that means we should occupy mmu lock for 1024 times
>> and walking shadow page cache for 1024 times, it is terrible
>>
>> In fact, if it is the repeat string instructions emulated and it is not a
>> IO/MMIO access, we can zap all the corresponding shadow pages and return to the
>> guest, then the mapping can became writable and directly write the page
>
> Please generalize this to fail emulation on all non-page-table instructions when emulating due to a write protected page that we can unprotect.
>
OK, will do it in the next version, thanks!
next prev parent reply other threads:[~2011-07-27 9:35 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-07-26 11:24 [PATCH 0/11] KVM: x86: optimize for guest page written Xiao Guangrong
2011-07-26 11:25 ` [PATCH 01/11] KVM: MMU: avoid pte_list_desc run out in kvm_mmu_pte_write Xiao Guangrong
2011-07-27 9:00 ` Avi Kivity
2011-07-27 9:37 ` Xiao Guangrong
2011-07-26 11:25 ` [PATCH 02/11] KVM: x86: cleanup pio/pout emulated Xiao Guangrong
2011-07-26 11:26 ` [PATCH 03/11] KVM: x86: fast emulate repeat string write instructions Xiao Guangrong
2011-07-26 12:27 ` Gleb Natapov
2011-07-26 13:53 ` Avi Kivity
2011-07-27 1:47 ` Xiao Guangrong
2011-07-27 4:26 ` Gleb Natapov
2011-07-27 6:32 ` Xiao Guangrong
2011-07-27 7:51 ` Gleb Natapov
2011-07-27 9:36 ` Xiao Guangrong
2011-07-27 9:04 ` Avi Kivity
2011-07-27 9:37 ` Xiao Guangrong [this message]
2011-07-26 11:28 ` [PATCH 04/11] KVM: MMU: do not mark access bit on pte write path Xiao Guangrong
2011-07-27 9:08 ` Avi Kivity
2011-07-27 10:04 ` Xiao Guangrong
2011-07-26 11:28 ` [PATCH 05/11] KVM: MMU: cleanup FNAME(invlpg) Xiao Guangrong
2011-07-26 11:29 ` [PATCH 06/11] KVM: MMU: fast prefetch spte on invlpg path Xiao Guangrong
2011-07-26 11:29 ` [PATCH 07/11] KVM: MMU: remove unnecessary kvm_mmu_free_some_pages Xiao Guangrong
2011-07-26 11:30 ` [PATCH 08/11] KVM: MMU: split kvm_mmu_pte_write function Xiao Guangrong
2011-07-26 11:31 ` [PATCH 09/11] KVM: MMU: remove the mismatch shadow page Xiao Guangrong
2011-07-27 9:11 ` Avi Kivity
2011-07-27 9:13 ` Avi Kivity
2011-07-27 10:05 ` Xiao Guangrong
2011-07-26 11:31 ` [PATCH 10/11] KVM: MMU: fix detecting misaligned accessed Xiao Guangrong
2011-07-27 9:15 ` Avi Kivity
2011-07-27 10:10 ` 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=4E2FDC6F.4050006@cn.fujitsu.com \
--to=xiaoguangrong@cn.fujitsu.com \
--cc=avi@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mtosatti@redhat.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.