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 A9F4B331ED1; Fri, 24 Jul 2026 16:31:55 +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=1784910716; cv=none; b=USUyk1hD0xtMbLT1Zs6QO2ezWHfFuJUgigTVPPyFstP/H+uSLIWJEb2B2tk80ukfv+0PCiHUrROdGtW8oox1kODAOGMv4BtYkcSzGdCm6QKUNI1ESlVe4f1cOEBaMeO5P5xSwx2snvNpQ2GLU97CywNbnCpP39EecVhu4BttEVI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784910716; c=relaxed/simple; bh=G2w6iLsaatqZ7CNkfPD+AKadfkixJdvJIetvgvFapUM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=NdIPk6IdmEZYCQV0tuF+E8jJ7UtFM6R5ietvTne3gWFHta1tk/9KnzxAmn8KeSc+KWCR2kDJ1R0t60BVAv7W6nyIFLpo8mC/kVL0Pgtj94zbZqd4bUCkVTLXNjow6gMecLQd2gXRPr5qrhjEtJELNp+/e7WJ0hxy316lsrZ+xHc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=WnAylZo5; 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="WnAylZo5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BCA661F00A3D; Fri, 24 Jul 2026 16:31:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784910715; bh=ZGnfLXs8/3ZZXMJGYBJ/MC8/fm2UhceZPaA8h6BrZ2U=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=WnAylZo5Q+efUUv2o4we0ojdl5IB/PfmSC2SdGJXKGIWWSFyDS7DILVY8LlqYG7l1 Sy8LG5Oem3ob7C49glLpBJGDH1xeGVyzdnsvKW2m79gw3cOs2eO88kJhfeTFI+w57W dPe2GKoxvgQZ9ggXMvvIpU++ahr/qkNS9XZRpKOHhCR/+AWiuVGuInFqXDPNRMer8w x7YFYzp84YlKN2m3i0itoRfgndqjaiOhHAiU8kh5CRtmuA4EPV799crK0fXIF8pU5l sn3L/tJZNS4cXZfCWA3sXJeZND7IDn0NpyqhbZd+aJqwQNmU7I3FWahBqq8JG2CM8t w9027hws69c3w== Message-ID: Date: Fri, 24 Jul 2026 18:31:51 +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 v2 12/13] mm/slab: add cache_ and slab_needs_objcg() helpers 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: <20260720-b4-objext_split-v2-0-2fa7c6f60dbe@kernel.org> <20260720-b4-objext_split-v2-12-2fa7c6f60dbe@kernel.org> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/24/26 11:41, Hao Li wrote: > On Mon, Jul 20, 2026 at 04:16:26PM +0200, Vlastimil Babka (SUSE) wrote: >> Slabs of some caches never need the objcg part of struct slabobj_ext. >> Introduce helpers to query this for a cache or a slab. >> >> Introduce SLAB_MAY_ACCOUNT flag that is currently only internal and only >> is_kmalloc_normal() caches don't have the flag. > > it seems this could be "only type == KMALLOC_NORMAL caches don't have this > flag". I think not, because with SLUB_TINY, a KMALLOC_NORMAL cache can have SLAB_RECLAIM_ACCOUNT flag and thus is not is_kmalloc_normal() and may need objcgs? Yep it's subtle :/