diff options
| author | Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp> | 2011-11-14 18:23:34 +0900 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2011-12-27 11:17:19 +0200 |
| commit | 7850ac5420803996e2960d15b924021f28e0dffc (patch) | |
| tree | dc4ed43a8e5ffcfbf45b48c8d78228ffe9762efa | |
| parent | 9b9b1492364758de82c19c36f07baa9ae162c7e5 (diff) | |
KVM: Count the number of dirty pages for dirty logging
Needed for the next patch which uses this number to decide how to write
protect a slot.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
| -rw-r--r-- | arch/x86/kvm/x86.c | 9 | ||||
| -rw-r--r-- | include/linux/kvm_host.h | 1 | ||||
| -rw-r--r-- | virt/kvm/kvm_main.c | 4 |
3 files changed, 7 insertions, 7 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index a3b25a524c9b..220c83b0fbda 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -3466,10 +3466,9 @@ 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; mutex_lock(&kvm->slots_lock); @@ -3484,11 +3483,8 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, n = kvm_dirty_bitmap_bytes(memslot); - 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->nr_dirty_pages) { struct kvm_memslots *slots, *old_slots; unsigned long *dirty_bitmap; @@ -3503,6 +3499,7 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, goto out; memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots)); slots->memslots[log->slot].dirty_bitmap = dirty_bitmap; + slots->memslots[log->slot].nr_dirty_pages = 0; slots->generation++; old_slots = kvm->memslots; diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index c6a2ec925846..7c654aa46b6c 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -181,6 +181,7 @@ struct kvm_memory_slot { unsigned long *rmap; unsigned long *dirty_bitmap; unsigned long *dirty_bitmap_head; + unsigned long nr_dirty_pages; struct kvm_lpage_info *lpage_info[KVM_NR_PAGE_SIZES - 1]; unsigned long userspace_addr; int user_alloc; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 4c5b9a239674..af5c988cafcc 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -625,6 +625,7 @@ static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot) return -ENOMEM; memslot->dirty_bitmap_head = memslot->dirty_bitmap; + memslot->nr_dirty_pages = 0; return 0; } #endif /* !CONFIG_S390 */ @@ -1491,7 +1492,8 @@ void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_memory_slot *memslot, if (memslot && memslot->dirty_bitmap) { unsigned long rel_gfn = gfn - memslot->base_gfn; - __set_bit_le(rel_gfn, memslot->dirty_bitmap); + if (!__test_and_set_bit_le(rel_gfn, memslot->dirty_bitmap)) + memslot->nr_dirty_pages++; } } |