From patchwork Tue Apr 20 10:56:17 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Takuya Yoshikawa X-Patchwork-Id: 93647 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter.kernel.org (8.14.3/8.14.3) with ESMTP id o3KAqdWW007026 for ; Tue, 20 Apr 2010 10:52:40 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754405Ab0DTKwh (ORCPT ); Tue, 20 Apr 2010 06:52:37 -0400 Received: from serv2.oss.ntt.co.jp ([222.151.198.100]:46761 "EHLO serv2.oss.ntt.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754141Ab0DTKwg (ORCPT ); Tue, 20 Apr 2010 06:52:36 -0400 Received: from serv2.oss.ntt.co.jp (localhost [127.0.0.1]) by serv2.oss.ntt.co.jp (Postfix) with ESMTP id 90A3224820B; Tue, 20 Apr 2010 19:52:35 +0900 (JST) Received: from serv1.oss.ntt.co.jp (serv1.oss.ntt.co.jp [172.19.0.2]) by serv2.oss.ntt.co.jp (Postfix) with ESMTP id 7F2F82481F9; Tue, 20 Apr 2010 19:52:35 +0900 (JST) Received: from yshtky3.kern.oss.ntt.co.jp (unknown [172.17.1.144]) by serv1.oss.ntt.co.jp (Postfix) with SMTP id 6369D11C11D; Tue, 20 Apr 2010 19:52:35 +0900 (JST) Date: Tue, 20 Apr 2010 19:56:17 +0900 From: Takuya Yoshikawa To: avi@redhat.com, mtosatti@redhat.com Cc: kvm@vger.kernel.org, kvm-ia64@vger.kernel.org, kvm-ppc@vger.kernel.org, fernando@oss.ntt.co.jp Subject: [PATCH RFC v2 1/6] KVM: introduce slot level dirty state management Message-Id: <20100420195617.0062cb74.yoshikawa.takuya@oss.ntt.co.jp> In-Reply-To: <20100420195349.dab60b1d.yoshikawa.takuya@oss.ntt.co.jp> References: <20100420195349.dab60b1d.yoshikawa.takuya@oss.ntt.co.jp> X-Mailer: Sylpheed 2.6.0 (GTK+ 2.16.1; i486-pc-linux-gnu) Mime-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter.kernel.org [140.211.167.41]); Tue, 20 Apr 2010 10:52:40 +0000 (UTC) diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c index d7bac1f..d60dafe 100644 --- a/arch/ia64/kvm/kvm-ia64.c +++ b/arch/ia64/kvm/kvm-ia64.c @@ -1824,6 +1824,9 @@ static int kvm_ia64_sync_dirty_log(struct kvm *kvm, base = memslot->base_gfn / BITS_PER_LONG; for (i = 0; i < n/sizeof(long); ++i) { + if (dirty_bitmap[base + i]) + memslot->is_dirty = true; + memslot->dirty_bitmap[i] = dirty_bitmap[base + i]; dirty_bitmap[base + i] = 0; } @@ -1838,7 +1841,6 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, int r; unsigned long n; struct kvm_memory_slot *memslot; - int is_dirty = 0; mutex_lock(&kvm->slots_lock); spin_lock(&kvm->arch.dirty_log_lock); @@ -1847,16 +1849,17 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, if (r) goto out; - r = kvm_get_dirty_log(kvm, log, &is_dirty); + r = kvm_get_dirty_log(kvm, log); if (r) goto out; + memslot = &kvm->memslots->memslots[log->slot]; /* If nothing is dirty, don't bother messing with page tables. */ - if (is_dirty) { + if (memslot->is_dirty) { kvm_flush_remote_tlbs(kvm); - memslot = &kvm->memslots->memslots[log->slot]; n = kvm_dirty_bitmap_bytes(memslot); memset(memslot->dirty_bitmap, 0, n); + memslot->is_dirty = false; } r = 0; out: diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c index 41c23b6..53b45cf 100644 --- a/arch/powerpc/kvm/book3s.c +++ b/arch/powerpc/kvm/book3s.c @@ -1118,20 +1118,18 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot; struct kvm_vcpu *vcpu; ulong ga, ga_end; - int is_dirty = 0; int r; unsigned long n; mutex_lock(&kvm->slots_lock); - r = kvm_get_dirty_log(kvm, log, &is_dirty); + r = kvm_get_dirty_log(kvm, log); if (r) goto out; + memslot = &kvm->memslots->memslots[log->slot]; /* If nothing is dirty, don't bother messing with page tables. */ - if (is_dirty) { - memslot = &kvm->memslots->memslots[log->slot]; - + if (memslot->is_dirty) { ga = memslot->base_gfn << PAGE_SHIFT; ga_end = ga + (memslot->npages << PAGE_SHIFT); @@ -1140,6 +1138,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, n = kvm_dirty_bitmap_bytes(memslot); memset(memslot->dirty_bitmap, 0, n); + memslot->is_dirty = false; } r = 0; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 58a96e6..76b23ed 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2724,10 +2724,9 @@ static int kvm_vm_ioctl_reinject(struct kvm *kvm, int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) { - int r, i; + int r; struct kvm_memory_slot *memslot; unsigned long n; - unsigned long is_dirty = 0; unsigned long *dirty_bitmap = NULL; mutex_lock(&kvm->slots_lock); @@ -2749,11 +2748,8 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, goto out; memset(dirty_bitmap, 0, n); - for (i = 0; !is_dirty && i < n/sizeof(long); i++) - is_dirty = memslot->dirty_bitmap[i]; - /* If nothing is dirty, don't bother messing with page tables. */ - if (is_dirty) { + if (memslot->is_dirty) { struct kvm_memslots *slots, *old_slots; spin_lock(&kvm->mmu_lock); @@ -2766,6 +2762,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots)); slots->memslots[log->slot].dirty_bitmap = dirty_bitmap; + slots->memslots[log->slot].is_dirty = false; old_slots = kvm->memslots; rcu_assign_pointer(kvm->memslots, slots); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 5583063..4446622 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -117,6 +117,7 @@ struct kvm_memory_slot { unsigned long flags; unsigned long *rmap; unsigned long *dirty_bitmap; + bool is_dirty; struct { unsigned long rmap_pde; int write_count; @@ -329,8 +330,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp, int kvm_dev_ioctl_check_extension(long ext); -int kvm_get_dirty_log(struct kvm *kvm, - struct kvm_dirty_log *log, int *is_dirty); +int kvm_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log); int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 3725605..cc78e07 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -764,13 +764,11 @@ int kvm_vm_ioctl_set_memory_region(struct kvm *kvm, return kvm_set_memory_region(kvm, mem, user_alloc); } -int kvm_get_dirty_log(struct kvm *kvm, - struct kvm_dirty_log *log, int *is_dirty) +int kvm_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) { struct kvm_memory_slot *memslot; - int r, i; + int r; unsigned long n; - unsigned long any = 0; r = -EINVAL; if (log->slot >= KVM_MEMORY_SLOTS) @@ -783,16 +781,10 @@ int kvm_get_dirty_log(struct kvm *kvm, n = kvm_dirty_bitmap_bytes(memslot); - for (i = 0; !any && i < n/sizeof(long); ++i) - any = memslot->dirty_bitmap[i]; - r = -EFAULT; if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n)) goto out; - if (any) - *is_dirty = 1; - r = 0; out: return r; @@ -1189,8 +1181,10 @@ void mark_page_dirty(struct kvm *kvm, gfn_t gfn) unsigned long rel_gfn = gfn - memslot->base_gfn; /* avoid RMW */ - if (!generic_test_le_bit(rel_gfn, memslot->dirty_bitmap)) + if (!generic_test_le_bit(rel_gfn, memslot->dirty_bitmap)) { generic___set_le_bit(rel_gfn, memslot->dirty_bitmap); + memslot->is_dirty = true; + } } }