From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Date: Thu, 28 Jun 2012 03:12:51 +0000 Subject: Re: [PATCH 5/6] KVM: Separate rmap_pde from kvm_lpage_info->write_count Message-Id: <4FEBCBB3.3060707@linux.vnet.ibm.com> List-Id: References: <20120628105733.ccd9abb3.yoshikawa.takuya@oss.ntt.co.jp> <20120628110141.7b908c91.yoshikawa.takuya@oss.ntt.co.jp> In-Reply-To: <20120628110141.7b908c91.yoshikawa.takuya@oss.ntt.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Takuya Yoshikawa Cc: avi@redhat.com, mtosatti@redhat.com, agraf@suse.de, paulus@samba.org, aarcange@redhat.com, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, linux-kernel@vger.kernel.org, takuya.yoshikawa@gmail.com On 06/28/2012 10:01 AM, Takuya Yoshikawa wrote: > This makes it possible to loop over rmap_pde arrays in the same way as > we do over rmap so that we can optimize kvm_handle_hva_range() easily in > the following patch. > > Signed-off-by: Takuya Yoshikawa > --- > arch/x86/include/asm/kvm_host.h | 2 +- > arch/x86/kvm/mmu.c | 6 +++--- > arch/x86/kvm/x86.c | 11 +++++++++++ > 3 files changed, 15 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h > index 5aab8d4..aea1673 100644 > --- a/arch/x86/include/asm/kvm_host.h > +++ b/arch/x86/include/asm/kvm_host.h > @@ -499,11 +499,11 @@ struct kvm_vcpu_arch { > }; > > struct kvm_lpage_info { > - unsigned long rmap_pde; > int write_count; > }; > > struct kvm_arch_memory_slot { > + unsigned long *rmap_pde[KVM_NR_PAGE_SIZES - 1]; > struct kvm_lpage_info *lpage_info[KVM_NR_PAGE_SIZES - 1]; > }; > It looks little complex than before - need manage more alloc-ed/freed buffers. Why not just introduce a function to get the next rmap? Something like this: static unsigned long *get_next_rmap(unsigned long *rmap, int level) { struct kvm_lpage_info *linfo if (level = 1) return rmap++ linfo = container_of(rmap, struct kvm_lpage_info, rmap_pde); return &(++linfo)->rmap_pde } [ Completely untested ]