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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 BDB95C3F68F for ; Sat, 8 Feb 2020 21:41:52 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 501C221741 for ; Sat, 8 Feb 2020 21:41:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 501C221741 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id AC4C16B0005; Sat, 8 Feb 2020 16:41:50 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A75026B0006; Sat, 8 Feb 2020 16:41:50 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 98A6C6B0007; Sat, 8 Feb 2020 16:41:50 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0184.hostedemail.com [216.40.44.184]) by kanga.kvack.org (Postfix) with ESMTP id 7F4D96B0005 for ; Sat, 8 Feb 2020 16:41:50 -0500 (EST) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 124A51F0A for ; Sat, 8 Feb 2020 21:41:50 +0000 (UTC) X-FDA: 76468282380.23.leg62_ffa4d40b1a0f X-HE-Tag: leg62_ffa4d40b1a0f X-Filterd-Recvd-Size: 1733 Received: from gentwo.org (gentwo.org [3.19.106.255]) by imf19.hostedemail.com (Postfix) with ESMTP for ; Sat, 8 Feb 2020 21:41:49 +0000 (UTC) Received: by gentwo.org (Postfix, from userid 1002) id 535B33F3D6; Sat, 8 Feb 2020 21:41:49 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by gentwo.org (Postfix) with ESMTP id 510343F242; Sat, 8 Feb 2020 21:41:49 +0000 (UTC) Date: Sat, 8 Feb 2020 21:41:49 +0000 (UTC) From: Christopher Lameter X-X-Sender: cl@www.lameter.com To: Wen Yang cc: Pekka Enberg , David Rientjes , Joonsoo Kim , Andrew Morton , Xunlei Pang , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/slub: Detach node lock from counting free objects In-Reply-To: <5373ce28-c369-4e40-11dd-b269e4d2cb24@linux.alibaba.com> Message-ID: References: <20200201031502.92218-1-wenyang@linux.alibaba.com> <5373ce28-c369-4e40-11dd-b269e4d2cb24@linux.alibaba.com> User-Agent: Alpine 2.21 (DEB 202 2017-01-01) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Bogosity: Ham, tests=bogofilter, spamicity=0.000016, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Sat, 8 Feb 2020, Wen Yang wrote: > I would greatly appreciate it if you kindly give me some feedback on this > patch. I think the measure is too severe given its use and the general impact on code. Maybe avoid taking the lock or reducing the time a lock is taken when reading /proc/slabinfo is the best approach? Also you could cache the value in the userspace application? Why is this value read continually?