From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-181.mta1.migadu.com (out-181.mta1.migadu.com [95.215.58.181]) (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 71DFE3C10A3 for ; Mon, 27 Jul 2026 06:22:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.181 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785133379; cv=none; b=aQfkU75+0lkmJRCfX4XcFZ78QAHTTVCJzApWqSL7zKl5Na38/4dvDO+kf5HccK+etTDu7WnBfujdDYT7qmof+7U1ADvLuADlqQuYApxCrR+1faExoJx91A+QulABEJGfEu6XuMVrDBym9QxPqBMnHv5ju/RMmE5zNY/Rf1zOBBU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785133379; c=relaxed/simple; bh=oKn0mWWTv1QZb/mmTUUqVa2q9YgHkp34zWxGkNt2S1Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=L16OH7DZjVffTLYJbbcIonwRfXGQpYClxuI6gRCP7n90CFOHfMPLAH5uNUFnzb16UjKasIoxJM1NI/KZwMd95r6MgbfPSfz3aZSMcSBNez2CSruEXoB/J3cSPxry9K7t0qF64uJLaAh6//TcYobkkIPLF3XsELjCipz2g6gjDz4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=nw9UfUv0; arc=none smtp.client-ip=95.215.58.181 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="nw9UfUv0" Date: Mon, 27 Jul 2026 14:22:39 +0800 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1785133371; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=JZmxPmsLA/v62j29nrs+JTmYYoheM7akRz2Dh6biEKQ=; b=nw9UfUv0xp3woEzgCFw5HyhW0GCyu3aS2xj0bjmL6xnk6YeODTbcjaI8uImAnTnURwcLB/ P/NnV8x8yKRmIRgc39KKTg/QlVKjw/W1rL/H2Cu6b50vm9FyUj//PtMhyEciQS9rHUXvC3 WyJnUGe4MEPLJs0AL6KAAJOQjxsa0Vs= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Hao Li To: Harry Yoo Cc: "Vlastimil Babka (SUSE)" , Suren Baghdasaryan , Shakeel Butt , Alexander Potapenko , Marco Elver , Andrew Morton , Christoph Lameter , David Rientjes , Roman Gushchin , linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Subject: Re: [PATCH v2 09/13] mm/slab: change struct slabobj_ext to a union Message-ID: References: <20260720-b4-objext_split-v2-0-2fa7c6f60dbe@kernel.org> <20260720-b4-objext_split-v2-9-2fa7c6f60dbe@kernel.org> <9b2dadb7-8e3d-4b9b-a870-969be9a7a432@kernel.org> <89662cae-b3d9-4aa4-a7fa-cf5931781dbc@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: <89662cae-b3d9-4aa4-a7fa-cf5931781dbc@kernel.org> X-Migadu-Flow: FLOW_OUT On Mon, Jul 27, 2026 at 02:41:20PM +0900, Harry Yoo wrote: > > > On 7/25/26 12:42 AM, Vlastimil Babka (SUSE) wrote: > > On 7/23/26 11:56, Hao Li wrote: > >> On Thu, Jul 23, 2026 at 03:27:51PM +0900, Harry Yoo wrote: > >>> > >>> and drop OBJEXT_FLAG_UNUSED. > >> > >> Yes, this idea is insightful and I think it may need a standalone patch without > >> blocking current patchset. > >> > >>> > >>> ...not sure how much we care about this on 32bit though. > >> > >> Yeah, 32bit is a rare arch today :) > > > > Agreed with you both. Let's deal with it later. > > Sounds reasonable. Yes, agree. > > > Also AFAICS the memory was already wasted on 32bit prior this series when > > e.g. CONFIG_MEM_ALLOC_PROFILING was disabled, so there was just 4-byte objcg > > pointer in 8-byte aligned slabobj_ext, right? > > Right. Exactly. -- Thanks, Hao