mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Keir Fraser <keirf@google.com>
To: linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org,  kvm@vger.kernel.org
Cc: Eric Auger <eric.auger@redhat.com>,
	Oliver Upton <oliver.upton@linux.dev>,
	 Marc Zyngier <maz@kernel.org>, Will Deacon <will@kernel.org>,
	Paolo Bonzini <pbonzini@redhat.com>,
	 Keir Fraser <keirf@google.com>
Subject: [PATCH 0/3] KVM: Speed up MMIO registrations
Date: Tue, 24 Jun 2025 09:22:52 +0000	[thread overview]
Message-ID: <20250624092256.1105524-1-keirf@google.com> (raw)

This series improves performance of MMIO registrations, which occur
multiple times when booting a typical VM. The existing call to
synchronize_srcu() may block for a considerable time: In our tests
it was found to account for approximately 25% of a VM's startup time.

arm64 vgic code is cleaned up and made responsible for
its own setup synchronization, and the MMIO registration logic
replaces synchronize_srcu() with a deferred callback to free the old
io_bus struct.

Keir Fraser (3):
  KVM: arm64: vgic-init: Remove vgic_ready() macro
  KVM: arm64: vgic: Explicitly implement vgic_dist::ready ordering
  KVM: Avoid synchronize_srcu() in kvm_io_bus_register_dev()

 arch/arm64/kvm/vgic/vgic-init.c | 14 +++-----------
 include/kvm/arm_vgic.h          |  1 -
 include/linux/kvm_host.h        |  1 +
 virt/kvm/kvm_main.c             | 10 ++++++++--
 4 files changed, 12 insertions(+), 14 deletions(-)

-- 
2.50.0.rc2.761.g2dc52ea45b-goog


             reply	other threads:[~2025-06-24  9:23 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-06-24  9:22 Keir Fraser [this message]
2025-06-24  9:22 ` [PATCH 1/3] KVM: arm64: vgic-init: Remove vgic_ready() macro Keir Fraser
2025-06-24  9:22 ` [PATCH 2/3] KVM: arm64: vgic: Explicitly implement vgic_dist::ready ordering Keir Fraser
2025-06-24  9:22 ` [PATCH 3/3] KVM: Avoid synchronize_srcu() in kvm_io_bus_register_dev() Keir Fraser
2025-06-24 15:11   ` Sean Christopherson
2025-06-30  9:59     ` Keir Fraser
2025-07-07 18:49       ` Sean Christopherson
2025-07-10  6:51         ` Keir Fraser
2025-07-10 13:34           ` Sean Christopherson
2025-07-15 12:43         ` Keir Fraser
2025-07-15 14:01           ` Sean Christopherson

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=20250624092256.1105524-1-keirf@google.com \
    --to=keirf@google.com \
    --cc=eric.auger@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=maz@kernel.org \
    --cc=oliver.upton@linux.dev \
    --cc=pbonzini@redhat.com \
    --cc=will@kernel.org \
    /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

all inboxes | Powered by JetHome®