From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f199.google.com (mail-pf0-f199.google.com [209.85.192.199]) by kanga.kvack.org (Postfix) with ESMTP id B23326B0038 for ; Wed, 18 Jan 2017 17:29:25 -0500 (EST) Received: by mail-pf0-f199.google.com with SMTP id z128so34236259pfb.4 for ; Wed, 18 Jan 2017 14:29:25 -0800 (PST) Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com. [148.163.156.1]) by mx.google.com with ESMTPS id 1si1464681plx.277.2017.01.18.14.29.24 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 18 Jan 2017 14:29:24 -0800 (PST) Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v0IMSlQN035230 for ; Wed, 18 Jan 2017 17:29:24 -0500 Received: from e35.co.us.ibm.com (e35.co.us.ibm.com [32.97.110.153]) by mx0a-001b2d01.pphosted.com with ESMTP id 282f61v94m-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 18 Jan 2017 17:29:24 -0500 Received: from localhost by e35.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 18 Jan 2017 15:29:23 -0700 Date: Wed, 18 Jan 2017 14:17:37 -0800 From: "Paul E. McKenney" Subject: Re: [PATCH RFC] mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU Reply-To: paulmck@linux.vnet.ibm.com References: <20170118110731.GA15949@linux.vnet.ibm.com> <20170118111201.GB29472@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170118111201.GB29472@bombadil.infradead.org> Message-Id: <20170118221737.GP5238@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: willy@infradead.org Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, cl@linux.com, penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com, akpm@linux-foundation.org On Wed, Jan 18, 2017 at 03:12:01AM -0800, willy@infradead.org wrote: > On Wed, Jan 18, 2017 at 03:07:32AM -0800, Paul E. McKenney wrote: > > A group of Linux kernel hackers reported chasing a bug that resulted > > from their assumption that SLAB_DESTROY_BY_RCU provided an existence > > guarantee, that is, that no block from such a slab would be reallocated > > during an RCU read-side critical section. Of course, that is not the > > case. Instead, SLAB_DESTROY_BY_RCU only prevents freeing of an entire > > slab of blocks. > > > > However, there is a phrase for this, namely "type safety". This commit > > therefore renames SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU in order > > to avoid future instances of this sort of confusion. > > This is probably the ultimate in bikeshedding, but RCU is not the > thing which is providing the typesafety. Slab is providing the > typesafety in order to help RCU. So would a better name not be > 'SLAB_TYPESAFETY_FOR_RCU', or more succinctly 'SLAB_RCU_TYPESAFE'? Actually, slab is using RCU to provide type safety to those slab users who request it. Thanx, Paul -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org