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=-6.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 D9F1AC4338F for ; Fri, 20 Aug 2021 13:43:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B9DD460FE6 for ; Fri, 20 Aug 2021 13:43:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240759AbhHTNnu (ORCPT ); Fri, 20 Aug 2021 09:43:50 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:42079 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229829AbhHTNns (ORCPT ); Fri, 20 Aug 2021 09:43:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1629466990; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4KjTjMbm6Ax2NoBz/SV8LRb7ROzLCYCzwIW7Ojvzm8c=; b=YD78ABzr1tiHYUcQ9Uf1Mp+hjDhEdBPds4spo57vKYHDE1dP7+0sxWSDjDU2Mi5FyvNc/t eXMPlVLP0WIIRKNAJHUpvkyOZbG+EiXEH6tmdyL1RgBJX/n+Ui2Mmqh7G4vIsIBkfbosGv D0PscFhC69sIV3VSvj6aOvtYho3guuA= Received: from mail-ej1-f70.google.com (mail-ej1-f70.google.com [209.85.218.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-603-gzy_ZX8bPEmHEBwKjp6i1w-1; Fri, 20 Aug 2021 09:41:46 -0400 X-MC-Unique: gzy_ZX8bPEmHEBwKjp6i1w-1 Received: by mail-ej1-f70.google.com with SMTP id s11-20020a170906060b00b005be824f15daso3732282ejb.2 for ; Fri, 20 Aug 2021 06:41:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:organization:user-agent:mime-version :content-transfer-encoding; bh=4KjTjMbm6Ax2NoBz/SV8LRb7ROzLCYCzwIW7Ojvzm8c=; b=JGTAeQX/Yro+fqudcdaUE0y1t0kylszj4e22JL1NlblfAFTVMR7asm0bRTuAzk71K9 TScUedK2wH2orOb9Jp5chO6aPhtkHva6+1dkQCwQYw7eYbkRltC/9Kc4vWoPFYP559Bt vpIJI0HDhysI1zpT1xX4NihTzh/GmKGvZgjNKrdZXa7cZnXr76pQ6yYSOdGHlfCJ72bN POGoF6YPJz2lZAmVPo5O9TbZFa/1C3GKxNin/8BwOgT9Rx7j9+nfl9X4TZFDtZyfipLN xhF0F+wEdmj1T9i3f4gqPofUpDjx2Tp2BINad0xT1CMaT2r5sERRt8F57pf+hm+VNLAj 5aHg== X-Gm-Message-State: AOAM533AxQq8FtlEUgLRs8Kz2b835G0G+2PM5xMoa/SsMUKjrUsa/EF6 caSibScu9qDqraKBiYD191c0zBKBo00+UO8AUnTFiB4WS8++Vuow7/vyrgQ/LNoAyYxbUZdpgxG ypU6xVl0fED/fiK8pVRHjzt9f X-Received: by 2002:aa7:db8b:: with SMTP id u11mr22178966edt.362.1629466893416; Fri, 20 Aug 2021 06:41:33 -0700 (PDT) X-Google-Smtp-Source: ABdhPJx0hLwN+s7rk8F847DLOmn4dy1Ao93kGJxxgV8+oY8fbxG+6Lejz40d6vR1Ye9lqW0fsphjXg== X-Received: by 2002:aa7:db8b:: with SMTP id u11mr22178939edt.362.1629466893221; Fri, 20 Aug 2021 06:41:33 -0700 (PDT) Received: from 0.7.3.c.2.b.0.0.0.3.7.8.9.5.0.2.0.0.0.0.a.d.f.f.0.b.8.0.1.0.0.2.ip6.arpa (0.7.3.c.2.b.0.0.0.3.7.8.9.5.0.2.0.0.0.0.a.d.f.f.0.b.8.0.1.0.0.2.ip6.arpa. [2001:8b0:ffda:0:2059:8730:b2:c370]) by smtp.gmail.com with ESMTPSA id g14sm3636121edr.47.2021.08.20.06.41.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Aug 2021 06:41:32 -0700 (PDT) Message-ID: <2508f12f0d2a5eedaad0c6b77657f53222b33e3c.camel@redhat.com> Subject: Re: [Cluster-devel] [PATCH v6 10/19] gfs2: Introduce flag for glock holder auto-demotion From: Steven Whitehouse To: Bob Peterson , Andreas Gruenbacher , Linus Torvalds , Alexander Viro , Christoph Hellwig , "Darrick J. Wong" Cc: Jan Kara , linux-kernel@vger.kernel.org, Matthew Wilcox , cluster-devel@redhat.com, linux-fsdevel@vger.kernel.org, ocfs2-devel@oss.oracle.com Date: Fri, 20 Aug 2021 14:41:32 +0100 In-Reply-To: References: <20210819194102.1491495-1-agruenba@redhat.com> <20210819194102.1491495-11-agruenba@redhat.com> <5e8a20a8d45043e88013c6004636eae5dadc9be3.camel@redhat.com> Organization: Red Hat UK Ltd Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.34.4 (3.34.4-1.fc31) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Fri, 2021-08-20 at 08:11 -0500, Bob Peterson wrote: > On 8/20/21 4:35 AM, Steven Whitehouse wrote: > > Hi, > > > > On Thu, 2021-08-19 at 21:40 +0200, Andreas Gruenbacher wrote: > > > From: Bob Peterson > > > > > > This patch introduces a new HIF_MAY_DEMOTE flag and > > > infrastructure > > > that > > > will allow glocks to be demoted automatically on locking > > > conflicts. > > > When a locking request comes in that isn't compatible with the > > > locking > > > state of a holder and that holder has the HIF_MAY_DEMOTE flag > > > set, > > > the > > > holder will be demoted automatically before the incoming locking > > > request > > > is granted. > > > > > I'm not sure I understand what is going on here. When there are > > locking > > conflicts we generate call backs and those result in glock > > demotion. > > There is no need for a flag to indicate that I think, since it is > > the > > default behaviour anyway. Or perhaps the explanation is just a bit > > confusing... > > I agree that the whole concept and explanation are confusing. > Andreas > and I went through several heated arguments about the symantics, > comments, patch descriptions, etc. We played around with many > different > flag name ideas, etc. We did not agree on the best way to describe > the > whole concept. He didn't like my explanation and I didn't like his. > So > yes, it is confusing. > That seems to be a good reason to take a step back and look at this a bit closer. If we are finding this confusing, then someone else looking at it at a future date, who may not be steeped in GFS2 knowledge is likely to find it almost impossible. So at least the description needs some work here I think, to make it much clearer what the overall aim is. It would be good to start with a statement of the problem that it is trying to solve which Andreas has hinted at in his reply just now, Steve. 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[2001:8b0:ffda:0:2059:8730:b2:c370]) by smtp.gmail.com with ESMTPSA id g14sm3636121edr.47.2021.08.20.06.41.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Aug 2021 06:41:32 -0700 (PDT) Message-ID: <2508f12f0d2a5eedaad0c6b77657f53222b33e3c.camel@redhat.com> From: Steven Whitehouse To: Bob Peterson , Andreas Gruenbacher , Linus Torvalds , Alexander Viro , Christoph Hellwig , "Darrick J. Wong" Date: Fri, 20 Aug 2021 14:41:32 +0100 In-Reply-To: References: <20210819194102.1491495-1-agruenba@redhat.com> <20210819194102.1491495-11-agruenba@redhat.com> <5e8a20a8d45043e88013c6004636eae5dadc9be3.camel@redhat.com> Organization: Red Hat UK Ltd User-Agent: Evolution 3.34.4 (3.34.4-1.fc31) MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=swhiteho@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Proofpoint-SPF-Result: pass X-Proofpoint-SPF-Record: v=spf1 ip4:103.23.64.2 ip4:103.23.65.2 ip4:103.23.66.26 ip4:103.23.67.26 ip4:107.21.15.141 ip4:108.177.8.0/21 ip4:128.17.0.0/20 ip4:128.17.128.0/20 ip4:128.17.192.0/20 ip4:128.17.64.0/20 ip4:128.245.0.0/20 ip4:128.245.64.0/20 ip4:13.110.208.0/21 ip4:13.110.216.0/22 ip4:13.111.0.0/16 ip4:136.147.128.0/20 ip4:136.147.176.0/20 include:spf1.redhat.com -all X-Proofpoint-SPF-VenPass: Allowed X-Source-IP: 216.205.24.124 X-ServerName: us-smtp-delivery-124.mimecast.com X-Proofpoint-SPF-Result: pass X-Proofpoint-SPF-Record: v=spf1 ip4:103.23.64.2 ip4:103.23.65.2 ip4:103.23.66.26 ip4:103.23.67.26 ip4:107.21.15.141 ip4:108.177.8.0/21 ip4:128.17.0.0/20 ip4:128.17.128.0/20 ip4:128.17.192.0/20 ip4:128.17.64.0/20 ip4:128.245.0.0/20 ip4:128.245.64.0/20 ip4:13.110.208.0/21 ip4:13.110.216.0/22 ip4:13.111.0.0/16 ip4:136.147.128.0/20 ip4:136.147.176.0/20 include:spf1.redhat.com -all X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=10081 signatures=668682 X-Proofpoint-Spam-Reason: safe X-Spam: OrgSafeList X-SpamRule: orgsafelist X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=10081 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 adultscore=0 bulkscore=0 suspectscore=0 mlxlogscore=999 phishscore=0 mlxscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2107140000 definitions=main-2108200077 Cc: Jan Kara , linux-kernel@vger.kernel.org, cluster-devel@redhat.com, linux-fsdevel@vger.kernel.org, ocfs2-devel@oss.oracle.com Subject: Re: [Ocfs2-devel] [Cluster-devel] [PATCH v6 10/19] gfs2: Introduce flag for glock holder auto-demotion X-BeenThere: ocfs2-devel@oss.oracle.com X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: ocfs2-devel-bounces@oss.oracle.com Errors-To: ocfs2-devel-bounces@oss.oracle.com X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=10081 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 bulkscore=0 malwarescore=0 mlxscore=0 spamscore=0 suspectscore=0 mlxlogscore=999 phishscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2107140000 definitions=main-2108200077 X-Proofpoint-ORIG-GUID: ldb-bxYf7idGe_qPJ6jx9mmJcRNtI6eC X-Proofpoint-GUID: ldb-bxYf7idGe_qPJ6jx9mmJcRNtI6eC Hi, On Fri, 2021-08-20 at 08:11 -0500, Bob Peterson wrote: > On 8/20/21 4:35 AM, Steven Whitehouse wrote: > > Hi, > > > > On Thu, 2021-08-19 at 21:40 +0200, Andreas Gruenbacher wrote: > > > From: Bob Peterson > > > > > > This patch introduces a new HIF_MAY_DEMOTE flag and > > > infrastructure > > > that > > > will allow glocks to be demoted automatically on locking > > > conflicts. > > > When a locking request comes in that isn't compatible with the > > > locking > > > state of a holder and that holder has the HIF_MAY_DEMOTE flag > > > set, > > > the > > > holder will be demoted automatically before the incoming locking > > > request > > > is granted. > > > > > I'm not sure I understand what is going on here. When there are > > locking > > conflicts we generate call backs and those result in glock > > demotion. > > There is no need for a flag to indicate that I think, since it is > > the > > default behaviour anyway. Or perhaps the explanation is just a bit > > confusing... > > I agree that the whole concept and explanation are confusing. > Andreas > and I went through several heated arguments about the symantics, > comments, patch descriptions, etc. We played around with many > different > flag name ideas, etc. We did not agree on the best way to describe > the > whole concept. He didn't like my explanation and I didn't like his. > So > yes, it is confusing. > That seems to be a good reason to take a step back and look at this a bit closer. If we are finding this confusing, then someone else looking at it at a future date, who may not be steeped in GFS2 knowledge is likely to find it almost impossible. So at least the description needs some work here I think, to make it much clearer what the overall aim is. It would be good to start with a statement of the problem that it is trying to solve which Andreas has hinted at in his reply just now, Steve. _______________________________________________ Ocfs2-devel mailing list Ocfs2-devel@oss.oracle.com https://oss.oracle.com/mailman/listinfo/ocfs2-devel From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Whitehouse Date: Fri, 20 Aug 2021 14:41:32 +0100 Subject: [Cluster-devel] [PATCH v6 10/19] gfs2: Introduce flag for glock holder auto-demotion In-Reply-To: References: <20210819194102.1491495-1-agruenba@redhat.com> <20210819194102.1491495-11-agruenba@redhat.com> <5e8a20a8d45043e88013c6004636eae5dadc9be3.camel@redhat.com> Message-ID: <2508f12f0d2a5eedaad0c6b77657f53222b33e3c.camel@redhat.com> List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Hi, On Fri, 2021-08-20 at 08:11 -0500, Bob Peterson wrote: > On 8/20/21 4:35 AM, Steven Whitehouse wrote: > > Hi, > > > > On Thu, 2021-08-19 at 21:40 +0200, Andreas Gruenbacher wrote: > > > From: Bob Peterson > > > > > > This patch introduces a new HIF_MAY_DEMOTE flag and > > > infrastructure > > > that > > > will allow glocks to be demoted automatically on locking > > > conflicts. > > > When a locking request comes in that isn't compatible with the > > > locking > > > state of a holder and that holder has the HIF_MAY_DEMOTE flag > > > set, > > > the > > > holder will be demoted automatically before the incoming locking > > > request > > > is granted. > > > > > I'm not sure I understand what is going on here. When there are > > locking > > conflicts we generate call backs and those result in glock > > demotion. > > There is no need for a flag to indicate that I think, since it is > > the > > default behaviour anyway. Or perhaps the explanation is just a bit > > confusing... > > I agree that the whole concept and explanation are confusing. > Andreas > and I went through several heated arguments about the symantics, > comments, patch descriptions, etc. We played around with many > different > flag name ideas, etc. We did not agree on the best way to describe > the > whole concept. He didn't like my explanation and I didn't like his. > So > yes, it is confusing. > That seems to be a good reason to take a step back and look at this a bit closer. If we are finding this confusing, then someone else looking at it at a future date, who may not be steeped in GFS2 knowledge is likely to find it almost impossible. So at least the description needs some work here I think, to make it much clearer what the overall aim is. It would be good to start with a statement of the problem that it is trying to solve which Andreas has hinted at in his reply just now, Steve.