From: Paolo Bonzini <pbonzini@redhat.com>
To: Marc Zyngier <maz@kernel.org>,
kvm@vger.kernel.org, linux-mips@vger.kernel.org,
kvmarm@lists.cs.columbia.edu, linuxppc-dev@lists.ozlabs.org
Cc: Juergen Gross <jgross@suse.com>,
Huacai Chen <chenhuacai@kernel.org>,
Janosch Frank <frankja@linux.ibm.com>,
Christian Borntraeger <borntraeger@de.ibm.com>,
Sean Christopherson <seanjc@google.com>,
Anup Patel <anup.patel@wdc.com>,
David Hildenbrand <david@redhat.com>,
Nicholas Piggin <npiggin@gmail.com>,
Atish Patra <atish.patra@wdc.com>,
Aleksandar Markovic <aleksandar.qemu.devel@gmail.com>,
Paul Mackerras <paulus@samba.org>,
James Morse <james.morse@arm.com>,
kernel-team@android.com,
Claudio Imbrenda <imbrenda@linux.ibm.com>,
Alexandru Elisei <alexandru.elisei@arm.com>,
Suzuki K Poulose <suzuki.poulose@arm.com>
Subject: Re: [PATCH 0/5] KVM: Turn the vcpu array into an xarray
Date: Tue, 16 Nov 2021 16:03:40 +0100 [thread overview]
Message-ID: <dd5292e5-7387-9797-2d74-6a3350cbe4f5@redhat.com> (raw)
In-Reply-To: <20211105192101.3862492-1-maz@kernel.org>
On 11/5/21 20:20, Marc Zyngier wrote:
> The kvm structure is pretty large. A large portion of it is the vcpu
> array, which is 4kB on x86_64 and arm64 as they deal with 512 vcpu
> VMs. Of course, hardly anyone runs VMs this big, so this is often a
> net waste of memory and cache locality.
>
> A possible approach is to turn the fixed-size array into an xarray,
> which results in a net code deletion after a bit of cleanup.
>
> This series is on top of the current linux/master as it touches the
> RISC-V implementation. Only tested on arm64.
Queued, only locally until I get a review for my replacement of patch 4
(see
https://lore.kernel.org/kvm/20211116142205.719375-1-pbonzini@redhat.com/T/).
Paolo
> Marc Zyngier (5):
> KVM: Move wiping of the kvm->vcpus array to common code
> KVM: mips: Use kvm_get_vcpu() instead of open-coded access
> KVM: s390: Use kvm_get_vcpu() instead of open-coded access
> KVM: x86: Use kvm_get_vcpu() instead of open-coded access
> KVM: Convert the kvm->vcpus array to a xarray
>
> arch/arm64/kvm/arm.c | 10 +---------
> arch/mips/kvm/loongson_ipi.c | 4 ++--
> arch/mips/kvm/mips.c | 23 ++---------------------
> arch/powerpc/kvm/powerpc.c | 10 +---------
> arch/riscv/kvm/vm.c | 10 +---------
> arch/s390/kvm/kvm-s390.c | 26 ++++++--------------------
> arch/x86/kvm/vmx/posted_intr.c | 2 +-
> arch/x86/kvm/x86.c | 9 +--------
> include/linux/kvm_host.h | 7 ++++---
> virt/kvm/kvm_main.c | 33 ++++++++++++++++++++++++++-------
> 10 files changed, 45 insertions(+), 89 deletions(-)
>
next prev parent reply other threads:[~2021-11-16 15:04 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-05 19:20 [PATCH 0/5] KVM: Turn the vcpu array into an xarray Marc Zyngier
2021-11-05 19:20 ` [PATCH 1/5] KVM: Move wiping of the kvm->vcpus array to common code Marc Zyngier
2021-11-05 20:12 ` Sean Christopherson
2021-11-06 11:17 ` Marc Zyngier
2021-11-16 13:49 ` Paolo Bonzini
2021-11-08 12:12 ` Claudio Imbrenda
2021-11-05 19:20 ` [PATCH 2/5] KVM: mips: Use kvm_get_vcpu() instead of open-coded access Marc Zyngier
2021-11-06 15:56 ` Philippe Mathieu-Daudé
2021-11-05 19:20 ` [PATCH 3/5] KVM: s390: " Marc Zyngier
2021-11-08 12:13 ` Claudio Imbrenda
2021-11-05 19:21 ` [PATCH 4/5] KVM: x86: " Marc Zyngier
2021-11-05 20:03 ` Sean Christopherson
2021-11-16 14:04 ` Paolo Bonzini
2021-11-16 16:07 ` Sean Christopherson
2021-11-16 16:48 ` Paolo Bonzini
2021-11-05 19:21 ` [PATCH 5/5] KVM: Convert the kvm->vcpus array to a xarray Marc Zyngier
2021-11-05 20:21 ` Sean Christopherson
2021-11-06 11:48 ` Marc Zyngier
2021-11-08 8:23 ` Marc Zyngier
2021-11-16 14:13 ` [PATCH 0/5] KVM: Turn the vcpu array into an xarray Juergen Gross
2021-11-16 14:21 ` Paolo Bonzini
2021-11-16 14:54 ` Juergen Gross
2021-11-16 15:03 ` Paolo Bonzini [this message]
2021-11-16 15:40 ` Marc Zyngier
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=dd5292e5-7387-9797-2d74-6a3350cbe4f5@redhat.com \
--to=pbonzini@redhat.com \
--cc=aleksandar.qemu.devel@gmail.com \
--cc=alexandru.elisei@arm.com \
--cc=anup.patel@wdc.com \
--cc=atish.patra@wdc.com \
--cc=borntraeger@de.ibm.com \
--cc=chenhuacai@kernel.org \
--cc=david@redhat.com \
--cc=frankja@linux.ibm.com \
--cc=imbrenda@linux.ibm.com \
--cc=james.morse@arm.com \
--cc=jgross@suse.com \
--cc=kernel-team@android.com \
--cc=kvm@vger.kernel.org \
--cc=kvmarm@lists.cs.columbia.edu \
--cc=linux-mips@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=maz@kernel.org \
--cc=npiggin@gmail.com \
--cc=paulus@samba.org \
--cc=seanjc@google.com \
--cc=suzuki.poulose@arm.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).