Re: [PATCH v8 08/14] KVM: selftests: Always clear dirty bitmap after iteration

[Andrew Jones]

On Tue, Mar 31, 2020 at 02:59:54PM -0400, Peter Xu wrote:
> We don't clear the dirty bitmap before because KVM_GET_DIRTY_LOG will
> clear it for us before copying the dirty log onto it.  However we'd
> still better to clear it explicitly instead of assuming the kernel
> will always do it for us.
> 
> More importantly, in the upcoming dirty ring tests we'll start to
> fetch dirty pages from a ring buffer, so no one is going to clear the
> dirty bitmap for us.
> 
> Signed-off-by: Peter Xu <peterx@xxxxxxxxxx>
> ---
>  tools/testing/selftests/kvm/dirty_log_test.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
> index 752ec158ac59..6a8275a22861 100644
> --- a/tools/testing/selftests/kvm/dirty_log_test.c
> +++ b/tools/testing/selftests/kvm/dirty_log_test.c
> @@ -195,7 +195,7 @@ static void vm_dirty_log_verify(enum vm_guest_mode mode, unsigned long *bmap)
>  				    page);
>  		}
>  
> -		if (test_bit_le(page, bmap)) {
> +		if (test_and_clear_bit_le(page, bmap)) {
>  			host_dirty_count++;
>  			/*
>  			 * If the bit is set, the value written onto
> -- 
> 2.24.1
>

Reviewed-by: Andrew Jones <drjones@xxxxxxxxxx>