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 67BF73ABDA5; Fri, 31 Jul 2026 13:52:49 +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=1785505971; cv=none; b=mNsdNEhssES6/4m+g5o+IKXdsBu18hqUXnEctLgm01MQMWvsO1Ai+NvN+UnKI+MGkM4R35QQPvsf9l88feBhksmcC4wP87N84QD12rx7MC28O72K06NieMx/ff1z5bkfS2kh80HpCebHwGsS7P3CUUvza+doEM0jRSUT/vkZc50= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785505971; c=relaxed/simple; bh=yiZNzkBAxT1rb8hkEUElVqTNdxoiPAf9WtXQ+XVmT/M=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=i53g0zAdWCSFRwv3oiUYA+jMyTsmwoDWqcKAEf9mPqDaLc2bLn059EzyffttnJDIm9x4jQF0v0NE4d5ExBt0cAj/1D5QVTvQuBlIjq25ce2CvzfV4zO9FzgXRuwi5k2Ffq8uSPIq8IUhFr/fuxl7fzVnPfFbXvT8fsWpMipMA8M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=D0y+qJ3D; 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="D0y+qJ3D" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 304431F000E9; Fri, 31 Jul 2026 13:52:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785505968; bh=cDEHYu+1/dZP45QPh68o+tAnVQBCZEowl8E2/iwoQoc=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=D0y+qJ3DABboRQb60kuGNjDtOgqw38ZaBeCzQ9tZVgoXDBxDijdVnq49T9BPLVnWc qPNgJCPgkUkC6HgEvUw/cqle+HO5Wqj0umQtyWK2KcI8MU4ICo7VtlvHNUSNfsDTqX wEiy43u8bFodHNHkdAupn6lRtCs5sp6L2XLFHfOURqEIiFwwcCswMMFj5oY+P1jxvi UT0YcZRzTkhGAu01Ghdh/Kbouw+1FmUT/sZSl8tH51oHtIpL1YvmqZWyxxfCvLv7ze zBdPv9SLGfn/1Zgcrm1NiCLLkY3kFuTvNNSZ/l0Rdd+XcsXUgBaFg+3TJ59EgEbXC1 uoRQMBmjjHE9A== Message-ID: <4b87664a-9ec6-4499-bc35-8c6f022f0881@kernel.org> Date: Fri, 31 Jul 2026 15:52:44 +0200 Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 08/13] mm/slab: change struct slabobj_ext to a union Content-Language: en-US To: Hao Li Cc: Harry Yoo , 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 References: <20260727-b4-objext_split-v3-0-c29ef0f1f257@kernel.org> <20260727-b4-objext_split-v3-8-c29ef0f1f257@kernel.org> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/30/26 13:58, Hao Li wrote: > On Mon, Jul 27, 2026 at 02:54:02PM +0200, Vlastimil Babka (SUSE) wrote: >> @@ -7933,7 +7936,7 @@ static int calculate_sizes(struct kmem_cache_args *args, struct kmem_cache *s) >> aligned_size = ALIGN(size, s->align); >> #if defined(CONFIG_SLAB_OBJ_EXT) && defined(CONFIG_64BIT) >> if (slab_args_unmergeable(args, s->flags) && >> - (aligned_size - size >= sizeof(struct slabobj_ext))) >> + (aligned_size - size >= cache_obj_ext_size(s))) > > Nit: cache_obj_ext_size() could return 0, and the checking will always be true. > But I think this is harmless. Yeah should be harmless as then no objexts are used for the cache anyway. Thanks! >> s->flags |= SLAB_OBJ_EXT_IN_OBJ; >> #endif >> size = aligned_size; >> >> -- >> 2.55.0 >> >