From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965105AbcBDCAg (ORCPT ); Wed, 3 Feb 2016 21:00:36 -0500 Received: from mx1.redhat.com ([209.132.183.28]:51634 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932706AbcBDCAd convert rfc822-to-8bit (ORCPT ); Wed, 3 Feb 2016 21:00:33 -0500 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 9.2 \(3112\)) Subject: Re: [PATCH 09/10] fs: ceph: Replace CURRENT_TIME by ktime_get_real_ts() From: "Yan, Zheng" In-Reply-To: <3267742.ulDeDOimis@wuerfel> Date: Thu, 4 Feb 2016 10:00:19 +0800 Cc: Deepa Dinamani , Zheng Yan , linux-fsdevel@vger.kernel.org, y2038@lists.linaro.org, Dave Chinner , "Theodore Ts'o" , linux-kernel , Sage Weil , Ilya Dryomov , ceph-devel Content-Transfer-Encoding: 8BIT Message-Id: References: <1454479670-8204-1-git-send-email-deepa.kernel@gmail.com> <20160203161720.GA9546@deepa-ubuntu> <3267742.ulDeDOimis@wuerfel> To: Arnd Bergmann Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Feb 4, 2016, at 05:27, Arnd Bergmann wrote: > > On Wednesday 03 February 2016 08:17:23 Deepa Dinamani wrote: >> On Wed, Feb 03, 2016 at 10:34:00PM +0800, Yan, Zheng wrote: >>> On Wed, Feb 3, 2016 at 2:07 PM, Deepa Dinamani wrote: >>>> --- a/fs/ceph/mds_client.c >>>> +++ b/fs/ceph/mds_client.c >>>> @@ -1721,7 +1721,7 @@ ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode) >>>> init_completion(&req->r_safe_completion); >>>> INIT_LIST_HEAD(&req->r_unsafe_item); >>>> >>>> - req->r_stamp = CURRENT_TIME; >>>> + ktime_get_real_ts(&req->r_stamp); >>> >>> I think we should use current_fs_time() here. I have squash the change >>> into another patch >> >> Ok. I missed this commit b8e69066d8afa8d2670dc697252ff0e5907aafad >> earlier which says that the r_stamp is used as ctime now. >> I had assumed that this is a message timestamp. >> >> I was not able to find any documentation on what the server does >> with the message sent by the client. Where can I find that? >> >> So, this should actually look like >> >> req->r_stamp = current_fs_time(mdsc->fsc->sb); >> >> Let me know if you want me to resend. I have already squashed the change into patch 8 > > I see that the timestamp is sent using > > ceph_encode_copy(&p, &req->r_stamp, sizeof(req->r_stamp)); this code is outdated, current code is: { struct ceph_timespec ts; ceph_encode_timespec(&ts, &req->r_stamp); ceph_encode_copy(&p, &ts, sizeof(ts)); } > > What happens with the timestamp across reboots if we change the > type? I assume the data will not be used across reboots, if it > does, we already have a problem on machines that can boot > both big-endian and little-endian kernels, or that can boot > both 32-bit and 64-bit kernels. > > Arnd