KVM Archive on lore.kernel.org
 help / color / Atom feed
From: Paolo Bonzini <pbonzini@redhat.com>
To: Peter Xu <peterx@redhat.com>
Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
	Sean Christopherson <sean.j.christopherson@intel.com>,
	linux-mips@vger.kernel.org,
	Vitaly Kuznetsov <vkuznets@redhat.com>
Subject: Re: [PATCH RFC 0/4] KVM: MIPS: Provide arch-specific kvm_flush_remote_tlbs()
Date: Tue, 17 Mar 2020 14:33:00 +0100
Message-ID: <2db8490e-e4a0-79d0-5088-a9571b01703d@redhat.com> (raw)
In-Reply-To: <20200311183201.GK479302@xz-x1>

On 11/03/20 19:32, Peter Xu wrote:
> On Wed, Feb 12, 2020 at 01:25:30PM +0100, Paolo Bonzini wrote:
>> On 07/02/20 23:35, Peter Xu wrote:
>>> [This series is RFC because I don't have MIPS to compile and test]
>>>
>>> kvm_flush_remote_tlbs() can be arch-specific, by either:
>>>
>>> - Completely replace kvm_flush_remote_tlbs(), like ARM, who is the
>>>   only user of CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL so far
>>>
>>> - Doing something extra before kvm_flush_remote_tlbs(), like MIPS VZ
>>>   support, however still wants to have the common tlb flush to be part
>>>   of the process.  Could refer to kvm_vz_flush_shadow_all().  Then in
>>>   MIPS it's awkward to flush remote TLBs: we'll need to call the mips
>>>   hooks.
>>>
>>> It's awkward to have different ways to specialize this procedure,
>>> especially MIPS cannot use the genenal interface which is quite a
>>> pity.  It's good to make it a common interface.
>>>
>>> This patch series removes the 2nd MIPS usage above, and let it also
>>> use the common kvm_flush_remote_tlbs() interface.  It should be
>>> suggested that we always keep kvm_flush_remote_tlbs() be a common
>>> entrance for tlb flushing on all archs.
>>>
>>> This idea comes from the reading of Sean's patchset on dynamic memslot
>>> allocation, where a new dirty log specific hook is added for flushing
>>> TLBs only for the MIPS code [1].  With this patchset, logically the
>>> new hook in that patch can be dropped so we can directly use
>>> kvm_flush_remote_tlbs().
>>>
>>> TODO: We can even extend another common interface for ranged TLB, but
>>> let's see how we think about this series first.
>>>
>>> Any comment is welcomed, thanks.
>>>
>>> Peter Xu (4):
>>>   KVM: Provide kvm_flush_remote_tlbs_common()
>>>   KVM: MIPS: Drop flush_shadow_memslot() callback
>>>   KVM: MIPS: Replace all the kvm_flush_remote_tlbs() references
>>>   KVM: MIPS: Define arch-specific kvm_flush_remote_tlbs()
>>>
>>>  arch/mips/include/asm/kvm_host.h |  7 -------
>>>  arch/mips/kvm/Kconfig            |  1 +
>>>  arch/mips/kvm/mips.c             | 22 ++++++++++------------
>>>  arch/mips/kvm/trap_emul.c        | 15 +--------------
>>>  arch/mips/kvm/vz.c               | 14 ++------------
>>>  include/linux/kvm_host.h         |  1 +
>>>  virt/kvm/kvm_main.c              | 10 ++++++++--
>>>  7 files changed, 23 insertions(+), 47 deletions(-)
>>>
>>
>> Compile-tested and queued.
> 
> Just in case it fells through the crach - Paolo, do you still have
> plan to queue this again?

Yes, I wanted to make it compile first though.  I'm undecided between
queuing your series and killing KVM MIPS honestly.

Paolo


  reply index

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-07 22:35 Peter Xu
2020-02-07 22:35 ` [PATCH RFC 1/4] KVM: Provide kvm_flush_remote_tlbs_common() Peter Xu
2020-02-12 13:33   ` Paolo Bonzini
2020-02-07 22:35 ` [PATCH RFC 2/4] KVM: MIPS: Drop flush_shadow_memslot() callback Peter Xu
2020-02-07 22:35 ` [PATCH RFC 3/4] KVM: MIPS: Replace all the kvm_flush_remote_tlbs() references Peter Xu
2020-02-07 22:35 ` [PATCH RFC 4/4] KVM: MIPS: Define arch-specific kvm_flush_remote_tlbs() Peter Xu
2020-03-18  3:03   ` maobibo
2020-03-18 15:28     ` Peter Xu
2020-03-19  2:21       ` maobibo
2020-02-07 23:00 ` [PATCH RFC 0/4] KVM: MIPS: Provide " Peter Xu
2020-02-12 12:25 ` Paolo Bonzini
2020-02-12 16:30   ` Paul Burton
2020-02-12 16:40     ` Paolo Bonzini
2020-02-12 19:02       ` Philippe Mathieu-Daudé
2020-03-11 18:32   ` Peter Xu
2020-03-17 13:33     ` Paolo Bonzini [this message]
2020-03-17 14:18       ` Peter Xu

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=2db8490e-e4a0-79d0-5088-a9571b01703d@redhat.com \
    --to=pbonzini@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mips@vger.kernel.org \
    --cc=peterx@redhat.com \
    --cc=sean.j.christopherson@intel.com \
    --cc=vkuznets@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

KVM Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/kvm/0 kvm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 kvm kvm/ https://lore.kernel.org/kvm \
		kvm@vger.kernel.org
	public-inbox-index kvm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.kvm


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git