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=-14.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 C8305C2B9F4 for ; Tue, 22 Jun 2021 23:38:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9DF3560FF2 for ; Tue, 22 Jun 2021 23:38:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229812AbhFVXlC (ORCPT ); Tue, 22 Jun 2021 19:41:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57800 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229704AbhFVXlB (ORCPT ); Tue, 22 Jun 2021 19:41:01 -0400 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13571C061574 for ; Tue, 22 Jun 2021 16:38:44 -0700 (PDT) Received: by mail-pj1-x1035.google.com with SMTP id s17-20020a17090a8811b029016e89654f93so2686897pjn.1 for ; Tue, 22 Jun 2021 16:38:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=M/6m21CIeeLekhwSUDpdwzXlcRZjjnme98V1uMVwYaQ=; b=oBixoQUOrEbqMLzMlyMWJm1ZV1ShFluEpoGu/t4mCDE7pRiriXXy1j+ci8fcpOZsPU 8daj4s7bQrBf44GEnZpuM/TqQRpvYlyGrJjS10o0Wpw9ZJTd3tnEbRemCcSbqPMTcPaq 4iug9g3B5OH2eAVqHBIH0uTvtPQfwUVrDmXtVXpHJOQeBGIRyQZlf27XLC65pK/4zmBY OMrUS/crvLyJzsjpOpTmGeBd9GNh1e93mH3jnMSqXZLTSap9Rvw6kHLEVG99eS32rLHD 3z3JiurCOBYLGE2MhdtJQ8QeN3/VHugNLqrsxsagjUhyroCkNt8NyfFjFMjiYBSFLoVX mLwg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=M/6m21CIeeLekhwSUDpdwzXlcRZjjnme98V1uMVwYaQ=; b=gnRx8jAsxX737tEiaAeTnpMLGZBXVShZdX2P2rsLOu+ZsVqxd0jJ55XqsBtQKTul4U /HbTy7KBZwgJnuUXpA0yvkdTLHcMyV7WyRl0NzglmmL5dK5IYPvivEYv4rUJ6SqGUCK6 OrL6BbpTwPaQSfan/K+MUp8enO9VU8OAF+MmUJtimcbfMuhbR8+vmLeqk3VZd4nfHJvv T4Evg3QJetlXCIXLo8IYTcohQlXUqVFiecpPr8O+PbPB1zty1DWdwyJp00zUHMA5GQzW +1Pv3Ds9KKV+F5/xUulPG8VL3uJWz2m2QUzCeNm60FqWfmgpqTgIS6GrSjDBn2uMDWSB KePA== X-Gm-Message-State: AOAM530qIyEFblifARnNEv7Xt5r3QTadzqALRhZp0KEUMYkm0LYoHBQv Mno7ei3sn4ch1oIElcLKmK4= X-Google-Smtp-Source: ABdhPJyeOhNsg2K3/x/qL9r1vg1bUYIKL1J6ODi4GdIG5hHpwuQvx4zAYhOW0RuU+Ob0Ke7T/fB9MA== X-Received: by 2002:a17:902:d489:b029:126:60a0:4797 with SMTP id c9-20020a170902d489b029012660a04797mr6339404plg.5.1624405123634; Tue, 22 Jun 2021 16:38:43 -0700 (PDT) Received: from google.com ([2620:15c:211:201:21b:31e:65b3:d681]) by smtp.gmail.com with ESMTPSA id y2sm352455pfa.195.2021.06.22.16.38.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 22 Jun 2021 16:38:42 -0700 (PDT) Sender: Minchan Kim Date: Tue, 22 Jun 2021 16:38:40 -0700 From: Minchan Kim To: Zhaoyang Huang Cc: Andrew Morton , Zhaoyang Huang , "open list:MEMORY MANAGEMENT" , LKML , Nitin Gupta , Sergey Senozhatsky Subject: Re: [PATCH] mm: zram: amend SLAB_RECLAIM_ACCOUNT on zspage_cachep Message-ID: References: <1623137297-29685-1-git-send-email-huangzhaoyang@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jun 21, 2021 at 10:35:26AM +0800, Zhaoyang Huang wrote: > On Sat, Jun 19, 2021 at 6:02 AM Minchan Kim wrote: > > > > On Tue, Jun 08, 2021 at 03:28:17PM +0800, Huangzhaoyang wrote: > > > From: Zhaoyang Huang > > > > > > Zspage_cachep is found be merged with other kmem cache during test, which > > > is not good for debug things(zs_pool->zspage_cachep present to be another > > > kmem cache in memory dumpfile). It is also neccessary to do so as shrinker has > > > > It's not a only problem of zsmalloc because slab want to minimize > > fragmentation so try to merge several objects if it's allowed. > > So I don't think it's particular problem of zsmalloc. > > I guess slub has some option maybe "nomerge" if you want it. > > > > > > been registered for zspage. Amending this flag can help kernel to calculate > > > SLAB_RECLAIMBLE correctly. > > > > > > Signed-off-by: Zhaoyang Huang > > > --- > > > mm/zsmalloc.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c > > > index 19b563b..0b0addd 100644 > > > --- a/mm/zsmalloc.c > > > +++ b/mm/zsmalloc.c > > > @@ -328,7 +328,7 @@ static int create_cache(struct zs_pool *pool) > > > return 1; > > > > > > pool->zspage_cachep = kmem_cache_create("zspage", sizeof(struct zspage), > > > - 0, 0, NULL); > > > + 0, SLAB_RECLAIM_ACCOUNT, NULL); > > > > How does zspage become SLAB_RECLAIM_ACCOUNT? > > > > I took the flag as "cacheable" object. IOW, when the shrinker > > ask to reclaim the object, it should reclaim(e.g., discarding) > > those objects for reclaming. However, that's not the case > > in zsmalloc. > alloc_slab will take the allocated object into account as > SLAB_RECLAIMABLE when this flag set on the kmem_cache My point is zspage_cachep is not an reclimable slab cache. Please describe why you believe it's reclaimable slab.