From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 625F0C18E5B for ; Tue, 10 Mar 2020 14:49:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 438112146E for ; Tue, 10 Mar 2020 14:49:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727320AbgCJOtA (ORCPT ); Tue, 10 Mar 2020 10:49:00 -0400 Received: from mga17.intel.com ([192.55.52.151]:49085 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726546AbgCJOtA (ORCPT ); Tue, 10 Mar 2020 10:49:00 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Mar 2020 07:48:59 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,537,1574150400"; d="scan'208";a="276977480" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.202]) by fmsmga002.fm.intel.com with ESMTP; 10 Mar 2020 07:48:59 -0700 Date: Tue, 10 Mar 2020 07:48:59 -0700 From: Sean Christopherson To: Peter Xu Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Yan Zhao , Jason Wang , Alex Williamson , Vitaly Kuznetsov , "Dr . David Alan Gilbert" , Christophe de Dinechin , "Michael S . Tsirkin" , Kevin Tian , Paolo Bonzini Subject: Re: [PATCH v6 02/14] KVM: Cache as_id in kvm_memory_slot Message-ID: <20200310144858.GA7600@linux.intel.com> References: <20200309214424.330363-1-peterx@redhat.com> <20200309214424.330363-3-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200309214424.330363-3-peterx@redhat.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Mon, Mar 09, 2020 at 05:44:12PM -0400, Peter Xu wrote: > Cache the address space ID just like the slot ID. It will be used in > order to fill in the dirty ring entries. > > Suggested-by: Paolo Bonzini > Suggested-by: Sean Christopherson > Signed-off-by: Peter Xu > --- > include/linux/kvm_host.h | 1 + > virt/kvm/kvm_main.c | 2 ++ > 2 files changed, 3 insertions(+) > > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index bcb9b2ac0791..afa0e9034881 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -346,6 +346,7 @@ struct kvm_memory_slot { > unsigned long userspace_addr; > u32 flags; > short id; > + u8 as_id; My vote is to store this as a u16 and remove the BUILD_BUG_ON. Using a u8 doesn't save any memory since the compiler will pad out the struct. > }; > > static inline unsigned long kvm_dirty_bitmap_bytes(struct kvm_memory_slot *memslot) > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 70f03ce0e5c1..e6484dabfc59 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -1036,6 +1036,8 @@ int __kvm_set_memory_region(struct kvm *kvm, > > new = old = *slot; > > + BUILD_BUG_ON(U8_MAX < KVM_ADDRESS_SPACE_NUM); > + new.as_id = as_id; > new.id = id; > new.base_gfn = base_gfn; > new.npages = npages; > -- > 2.24.1 >