From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Subject: Re: [PATCH v3 10/11] KVM: MMU: clear write-flooding on the fast path of tracked page Date: Tue, 23 Feb 2016 12:36:25 +0800 Message-ID: <56CBE1C9.7070204@linux.intel.com> References: <1455449503-20993-1-git-send-email-guangrong.xiao@linux.intel.com> <1455449503-20993-11-git-send-email-guangrong.xiao@linux.intel.com> <56C7029F.8010106@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: gleb@kernel.org, mtosatti@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, kai.huang@linux.intel.com, jike.song@intel.com To: Paolo Bonzini Return-path: In-Reply-To: <56C7029F.8010106@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 02/19/2016 07:55 PM, Paolo Bonzini wrote: > > > On 14/02/2016 12:31, Xiao Guangrong wrote: >> If the page fault is caused by write access on write tracked page, the >> real shadow page walking is skipped, we lost the chance to clear write >> flooding for the page structure current vcpu is using >> >> Fix it by locklessly waking shadow page table to clear write flooding >> on the shadow page structure out of mmu-lock. So that we change the >> count to atomic_t > > Should this be moved earlier in the series, so that the issue never > surfaces? Okay, i will move it to the place that is behind: [PATCH v3 06/11] KVM: MMU: let page fault handler be aware tracked page