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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 77423C61DA4 for ; Thu, 23 Feb 2023 01:04:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233055AbjBWBEW (ORCPT ); Wed, 22 Feb 2023 20:04:22 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49620 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233038AbjBWBEU (ORCPT ); Wed, 22 Feb 2023 20:04:20 -0500 Received: from mail-pj1-x1036.google.com (mail-pj1-x1036.google.com [IPv6:2607:f8b0:4864:20::1036]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9E9332CC46 for ; Wed, 22 Feb 2023 17:03:57 -0800 (PST) Received: by mail-pj1-x1036.google.com with SMTP id l1so729529pjt.2 for ; Wed, 22 Feb 2023 17:03:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=WeVf+lvGNeVYubOJ3KmhlwMD0qDbcIcPAA2fSn/VLqI=; b=eUM2OCcj2hc2PrhAjQULqh1Ap6c6rwgKSXbSnPKR3n7tl9VN6COEM/V7oa6XtHgc1o 8DouMvF8dGS+e5bk9wKEM24Rvk5WogEf9k+aIzh52nH7XmqZVOHxCUkjICO0qMR1aiqq gm+t9gGJBUgTjaCAGYSZk1TFzoPhhTNuIO2SgjD75/lyc0QSdTZL0r6/6vmWi4EQeXGk zbEdur62BFlMDqX9n5dSHCmpWd3rkWvwwlqPAqeA+6RGWHYsD5lhFLnvgBWjVFdr9lXu IT7v6+pbqT4CXHTmaFIEIpYFWy+GCUVd5iS5UjkKtAEBhG9aZI4Z10Iq5cqF+4ezx51z y1Hw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=WeVf+lvGNeVYubOJ3KmhlwMD0qDbcIcPAA2fSn/VLqI=; b=auNjOwvtSiQlxRFkjusAfB6ajt63EWn6SlygZFmdwn7LkXlTIl6XIWGHtii8n3ATvu 0eYCrckEQt1JmYC/7/d2McR8Ow5lEq+QzI7WH5dMquObyjyd2DAA5FiGJBb8kACvbAzN eRUAgRn8dnnmEVPwN2F90fCEk2v5FSwu4zdlWsMISmNB44m9GHzuKmY3sSOB56hUV1DG U1FeVEIcKiBCaztMYutMDWiGcMAPTuTkV6CA4Bk/HRdz9d6G91bpddxNfYL+IGCARlgf M5qgec/4iZLsernBT6JjGz3NAy+JSxYOK0ARkuBz2fePLJh96Mf8qT47LfeVAugU1HpY t0Gg== X-Gm-Message-State: AO0yUKX4x8Tu+2aj9Ng6Mx9d8k8GYN9ZvBUChrkwTjExqE2lJO56E29X I+OCbeqa8+Jvl4528XA71d3KVNscRlA= X-Google-Smtp-Source: AK7set8TXzXaC2/fn0bf1HEdmolAPvXAKURAvIMr8ybRUcpKdxXj2NVbwHr01MjBJ8TL++W/fB2HVA== X-Received: by 2002:a05:6a21:329e:b0:c2:b249:fe9a with SMTP id yt30-20020a056a21329e00b000c2b249fe9amr12729950pzb.18.1677114236845; Wed, 22 Feb 2023 17:03:56 -0800 (PST) Received: from localhost ([2400:8902::f03c:93ff:fe27:642a]) by smtp.gmail.com with ESMTPSA id n15-20020aa7904f000000b005a8da960fa8sm5648149pfo.144.2023.02.22.17.03.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Feb 2023 17:03:55 -0800 (PST) Date: Thu, 23 Feb 2023 01:03:49 +0000 From: Hyeonggon Yoo <42.hyeyoo@gmail.com> To: Vernon Yang Cc: akpm@linux-foundation.org, vbabka@suse.cz, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm/slub: fix help comment of SLUB_DEBUG[_ON] Message-ID: References: <20230222232058.66971-1-vernon2gm@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230222232058.66971-1-vernon2gm@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 23, 2023 at 07:20:58AM +0800, Vernon Yang wrote: > Since commit 081248de0a02 ("kset: move /sys/slab to /sys/kernel/slab"), > the SYSFS path of slab was modified, so fix up the help comment of > SLUB_DEBUG to use the correct one. > > And now the "slub_debug" parameter on boot that is support for more > fine grained debug control, so fix up help comment of SLUB_DEBUG_ON > for "no support" to "support". > > Signed-off-by: Vernon Yang > --- > mm/Kconfig.debug | 12 ++++++------ > 1 file changed, 6 insertions(+), 6 deletions(-) > > diff --git a/mm/Kconfig.debug b/mm/Kconfig.debug > index fca699ad1fb0..732043bf56c6 100644 > --- a/mm/Kconfig.debug > +++ b/mm/Kconfig.debug > @@ -61,8 +61,8 @@ config SLUB_DEBUG > help > SLUB has extensive debug support features. Disabling these can > result in significant savings in code size. This also disables > - SLUB sysfs support. /sys/slab will not exist and there will be > - no support for cache validation etc. > + SLUB sysfs support. /sys/kernel/slab will not exist and there > + will be no support for cache validation etc. After commit ab4d5ed5eeda ("slub: Enable sysfs support for !CONFIG_SLUB_DEBUG"), "Disabling SLUB_DEBUG also disables SLUB sysfs support" is not true anymore. > config SLUB_DEBUG_ON > bool "SLUB debugging on by default" > @@ -73,10 +73,10 @@ config SLUB_DEBUG_ON > Boot with debugging on by default. SLUB boots by default with > the runtime debug capabilities switched off. Enabling this is > equivalent to specifying the "slub_debug" parameter on boot. > - There is no support for more fine grained debug control like > - possible with slub_debug=xxx. SLUB debugging may be switched > - off in a kernel built with CONFIG_SLUB_DEBUG_ON by specifying > - "slub_debug=-". > + There is support for more fine grained debug control like > + possible with slub_debug=xxx, details in Documentation/mm/slub.rst. > + SLUB debugging may be switched off in a kernel built with > + CONFIG_SLUB_DEBUG_ON by specifying "slub_debug=-". I think this is a misunderstanding. SLUB_DEBUG_ON is equivalent to passing boot parameter slub_debug=FUPZ, and what the help text says is that "You can enable slub debugging by default using this config option but there is no support for fine-grained control like what slub_debug boot parameter provides." IOW SLUB_DEBUG_ON cannot be used to have same effect as passing something like slub_debug=F. > > config PAGE_OWNER > bool "Track page owner" > -- > 2.34.1 > >