From patchwork Thu May 28 04:45:54 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marcelo Tosatti X-Patchwork-Id: 26661 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n4S4t1XG009118 for ; Thu, 28 May 2009 04:55:01 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751734AbZE1Eyy (ORCPT ); Thu, 28 May 2009 00:54:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751673AbZE1Eyy (ORCPT ); Thu, 28 May 2009 00:54:54 -0400 Received: from mx2.redhat.com ([66.187.237.31]:35478 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751083AbZE1Eyt (ORCPT ); Thu, 28 May 2009 00:54:49 -0400 Received: from int-mx2.corp.redhat.com (int-mx2.corp.redhat.com [172.16.27.26]) by mx2.redhat.com (8.13.8/8.13.8) with ESMTP id n4S4sqKC020742 for ; Thu, 28 May 2009 00:54:52 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx2.corp.redhat.com (8.13.1/8.13.1) with ESMTP id n4S4spRY007305; Thu, 28 May 2009 00:54:51 -0400 Received: from amt.cnet (vpn-10-6.str.redhat.com [10.32.10.6]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id n4S4snNO020726; Thu, 28 May 2009 00:54:50 -0400 Received: from amt.cnet (amt.cnet [127.0.0.1]) by amt.cnet (Postfix) with ESMTP id 63F8255804C; Thu, 28 May 2009 01:54:15 -0300 (BRT) Received: (from marcelo@localhost) by amt.cnet (8.14.3/8.14.3/Submit) id n4S4sEM8011498; Thu, 28 May 2009 01:54:14 -0300 Message-Id: <20090528044808.205238362@localhost.localdomain> References: <20090528044552.151652861@localhost.localdomain> In-Reply-To: <4A19553F.1090903@redhat.com> User-Agent: quilt/0.46-1 Date: Thu, 28 May 2009 01:45:54 -0300 From: Marcelo Tosatti To: kvm@vger.kernel.org Cc: Marcelo Tosatti Subject: [patch 2/4] KVM: move coalesced_mmio locking to its own device Content-Disposition: inline; filename=coalesced-mmio-lock X-Scanned-By: MIMEDefang 2.58 on 172.16.27.26 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Move coalesced_mmio locking to its own device, instead of relying on kvm->lock. Signed-off-by: Marcelo Tosatti Index: kvm-irqlock/virt/kvm/coalesced_mmio.c =================================================================== --- kvm-irqlock.orig/virt/kvm/coalesced_mmio.c +++ kvm-irqlock/virt/kvm/coalesced_mmio.c @@ -26,9 +26,7 @@ static int coalesced_mmio_in_range(struc if (!is_write) return 0; - /* kvm->lock is taken by the caller and must be not released before - * dev.read/write - */ + spin_lock(&dev->lock); /* Are we able to batch it ? */ @@ -41,7 +39,7 @@ static int coalesced_mmio_in_range(struc KVM_COALESCED_MMIO_MAX; if (next == dev->kvm->coalesced_mmio_ring->first) { /* full */ - return 0; + goto out_denied; } /* is it in a batchable area ? */ @@ -57,6 +55,8 @@ static int coalesced_mmio_in_range(struc addr + len <= zone->addr + zone->size) return 1; } +out_denied: + spin_unlock(&dev->lock); return 0; } @@ -67,8 +67,6 @@ static void coalesced_mmio_write(struct (struct kvm_coalesced_mmio_dev*)this->private; struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring; - /* kvm->lock must be taken by caller before call to in_range()*/ - /* copy data in first free entry of the ring */ ring->coalesced_mmio[ring->last].phys_addr = addr; @@ -76,6 +74,7 @@ static void coalesced_mmio_write(struct memcpy(ring->coalesced_mmio[ring->last].data, val, len); smp_wmb(); ring->last = (ring->last + 1) % KVM_COALESCED_MMIO_MAX; + spin_unlock(&dev->lock); } static void coalesced_mmio_destructor(struct kvm_io_device *this) @@ -90,6 +89,8 @@ int kvm_coalesced_mmio_init(struct kvm * dev = kzalloc(sizeof(struct kvm_coalesced_mmio_dev), GFP_KERNEL); if (!dev) return -ENOMEM; + spin_lock_init(&dev->lock); + dev->dev.write = coalesced_mmio_write; dev->dev.in_range = coalesced_mmio_in_range; dev->dev.destructor = coalesced_mmio_destructor; Index: kvm-irqlock/virt/kvm/coalesced_mmio.h =================================================================== --- kvm-irqlock.orig/virt/kvm/coalesced_mmio.h +++ kvm-irqlock/virt/kvm/coalesced_mmio.h @@ -12,6 +12,7 @@ struct kvm_coalesced_mmio_dev { struct kvm_io_device dev; struct kvm *kvm; + spinlock_t lock; int nb_zones; struct kvm_coalesced_mmio_zone zone[KVM_COALESCED_MMIO_ZONE_MAX]; };