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=-2.3 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 EE978C3A5A1 for ; Mon, 26 Aug 2019 00:48:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CF0C62080C for ; Mon, 26 Aug 2019 00:48:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729062AbfHZAsN (ORCPT ); Sun, 25 Aug 2019 20:48:13 -0400 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:48565 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726281AbfHZAsK (ORCPT ); Sun, 25 Aug 2019 20:48:10 -0400 Received: from callcc.thunk.org (guestnat-104-133-0-111.corp.google.com [104.133.0.111] (may be forged)) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id x7Q0li6E014485 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 25 Aug 2019 20:47:46 -0400 Received: by callcc.thunk.org (Postfix, from userid 15806) id A868042049E; Sun, 25 Aug 2019 20:47:44 -0400 (EDT) Date: Sun, 25 Aug 2019 20:47:44 -0400 From: "Theodore Y. Ts'o" To: Shaokun Zhang , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, Yang Guo , Andreas Dilger Subject: Re: [PATCH] ext4: change the type of ext4 cache stats to percpu_counter to improve performance Message-ID: <20190826004744.GA27472@mit.edu> Mail-Followup-To: "Theodore Y. Ts'o" , Shaokun Zhang , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, Yang Guo , Andreas Dilger References: <1566528454-13725-1-git-send-email-zhangshaokun@hisilicon.com> <20190825032524.GD5163@mit.edu> <20190825172803.GA9505@sol.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190825172803.GA9505@sol.localdomain> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Aug 25, 2019 at 10:28:03AM -0700, Eric Biggers wrote: > This patch is causing the following. Probably because there's no calls to > percpu_counter_destroy() for the new counters? Yeah, I noticed this from my test runs last night as well. It looks like original patch was never tested with CONFIG_HOTPLUG_CPU. The other problem with this patch is that it initializes es_stats_cache_hits and es_stats_cache_miesses too late. They will get used when the journal inode is loaded. This is mostly harmless, but it's also wrong. I've dropped this patch from the ext4 git tree. - Ted