From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A993339934B for ; Thu, 24 Sep 2026 15:18:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790263139; cv=none; b=p1RukXt+HbMMygkeMGWuJ0iuqQvCZzkDqpWsXzStM5LMRtR+SKmzPE68kjKa0cFPGU4qVnZgxuRo31ZOvaQ2PL8ZdfxR2pIwk9+993P2j/+kKGiLTsAoJLXUDuoegzzzdODVT13FwjMIA0djVHcqSU5iDKJG45Ee6Aw2cw+1tfY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790263139; c=relaxed/simple; bh=RtRCphddFy8zJQ+8c8C1JPE8grvQpuSu4FeGPB4Xko4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=nTQ2XBu5E9IUu1qciYJ8UA8acMQKnzpxgEbI0YxWBExQumaV2DEM1Z3S+lX9UMgXeTGadX15SffO0s9cUrkPfPhsT54E+37Bi7LWvp+G1/o+nSf6RCEygwMycTjzRwjN1g9tylBQ/gxrqsFg5SoJjZdPRWUSUYhP+BIyViKw9K4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VVDH9WLs; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VVDH9WLs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E6A61F000FF; Thu, 24 Sep 2026 15:18:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790263138; bh=r7s1CAgd45i1qVFJKno+reNnGoGUQMAT+I7uYiP/nks=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=VVDH9WLsvrmzpUg4Z+hLDHBG/pO4qlIBnTIodD5pt0BF9Re7iMX6ULoPqbHSz2RnM mymMnw1a5pmRQCiKHNjX4xaFkJd3E2HmVEGs+O7u5jfWVN5bmkH6nlOUe7THYjtE/f mL9o7Tj6iKdrgU8ZuOjyGB03amWLl/t1FrPbO9ve033yVQ+VQR2hizSLCNpgOzVIWT 6XnXVTerX2Y6rVe8Mk+UHq65CpLKmamkWuT4mkfE3jZlWwLjl051pbc+nuoNQpiPAh +Z2Nny5WtQQtwJzs7+VmPoQhFBBLhVHeoXzW8TFatOOXvBDWsF+IG4mzjumIzBkQ0I foBvXytVcx/3g== Date: Thu, 24 Sep 2026 16:18:56 +0100 From: Harry Yoo To: "Vlastimil Babka (SUSE)" Cc: Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , Geert Uytterhoeven , Conor Dooley , Damien Le Moal , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC 0/8] replace CONFIG_SLUB_TINY with a slab_tiny boot parameter Message-ID: References: <20260923-slub_tiny_rework-v1-0-a0e66d536eb5@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260923-slub_tiny_rework-v1-0-a0e66d536eb5@kernel.org> On Wed, Sep 23, 2026 at 05:45:05PM +0200, Vlastimil Babka (SUSE) wrote: > To sum up, after this series: > > - CONFIG_SLUB_TINY is a deprecated option that has no interaction with > other options and only controls the default behavior. > > - New slab_tiny boot parameter controls the functionality (and can > override CONFIG_SLUB_TINY in both directions). > > - slab_debug=N can effectively achieve most of slab_tiny and on a > per-cache basic Allowing "slab_tiny=0" doesn't make much sense given that CONFIG_SLUB_TINY is deprecated anyway. I was assuming specifying "slab_tiny" would enable it and not specifying it would disable it unless CONFIG_SLUB_TINY is set. Also it's bit confusing to have multiple ways to achieve the same thing. Is there a reason why we can't interpret "slab_debug=N" as "slab_tiny_enabled = 1" internally and drop "slab_tiny" boot parameter? > - the implementation is simpler with many ifdefs removed > > [1] https://lore.kernel.org/all/CAHk-=wh-k04MsoEC0SGKff2Snm6bBF_e+0pHOKwaWv4umZ_SnQ@mail.gmail.com/ > > Signed-off-by: Vlastimil Babka (SUSE) > --- > Vlastimil Babka (SUSE) (8): > mm, slab: refactor slab_min/max_order handling > mm, slab: introduce slab_debug=N > mm, slab: rework KMALLOC_RECLAIM handling of SLUB_TINY > mm, slab: make SLUB_TINY handling dynamic for sizing decisions > mm, slab: convert CONFIG_SLUB_TINY checks to kmem_cache_debug() > mm, slab: remove remaining compile-time checks for CONFIG_SLUB_TINY > mm, slab: add slab_tiny boot param > mm, slab: deprecate CONFIG_SLUB_TINY and reduce its Kconfig effects > > Documentation/admin-guide/kernel-parameters.txt | 4 + > Documentation/admin-guide/mm/slab.rst | 18 ++- > include/linux/slab.h | 17 +-- > lib/Kconfig.kasan | 2 +- > mm/Kconfig | 16 ++- > mm/Kconfig.debug | 2 +- > mm/slab.h | 32 +++-- > mm/slab_common.c | 12 +- > mm/slub.c | 149 +++++++++++------------- > 9 files changed, 120 insertions(+), 132 deletions(-) > --- > base-commit: b4218126d498275444f315b0ed4cef6add6beabc > change-id: 20260911-slub_tiny_rework-8f2634dd17a7 > -- Cheers, Harry / Hyeonggon