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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id CC3A8C433EF for ; Mon, 22 Nov 2021 09:26:23 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 471C06B0071; Mon, 22 Nov 2021 04:26:08 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 3F8086B0072; Mon, 22 Nov 2021 04:26:08 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2BF6D6B0073; Mon, 22 Nov 2021 04:26:08 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0175.hostedemail.com [216.40.44.175]) by kanga.kvack.org (Postfix) with ESMTP id 181096B0071 for ; Mon, 22 Nov 2021 04:26:08 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id CE819886FC for ; Mon, 22 Nov 2021 09:25:57 +0000 (UTC) X-FDA: 78836034606.05.3CCEF6C Received: from gentwo.de (gentwo.de [161.97.139.209]) by imf22.hostedemail.com (Postfix) with ESMTP id D7891192D for ; Mon, 22 Nov 2021 09:25:56 +0000 (UTC) Received: by gentwo.de (Postfix, from userid 1001) id 66113B00549; Mon, 22 Nov 2021 10:25:56 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by gentwo.de (Postfix) with ESMTP id 652C4B0049C; Mon, 22 Nov 2021 10:25:56 +0100 (CET) Date: Mon, 22 Nov 2021 10:25:56 +0100 (CET) From: Christoph Lameter X-X-Sender: cl@gentwo.de To: Wonhyuk Yang cc: linux-mm@kvack.org, Joonsoo Kim Subject: Re: [Question] The necessity of transaction ID in SLUB. In-Reply-To: Message-ID: References: User-Agent: Alpine 2.22 (DEB 394 2020-01-19) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: D7891192D Authentication-Results: imf22.hostedemail.com; dkim=none; dmarc=none; spf=none (imf22.hostedemail.com: domain of cl@gentwo.org has no SPF policy when checking 161.97.139.209) smtp.mailfrom=cl@gentwo.org X-Stat-Signature: e1y3g3bdz7gxrx9t5x6p3tusz9r3ffxg X-HE-Tag: 1637573156-143498 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sun, 21 Nov 2021, Wonhyuk Yang wrote: > 1) c->cpu_slab->page is unfrozen and frozen by another cpu. (is it possible?) Yes. > In the first case, cpu_slab structure can be different. But updating > freelist isn't a problem. It is a problem because the update can occur on a different processor without the TID which can race with another update on another processor.