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 4B8553BFE34; Wed, 29 Jul 2026 09:27:13 +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=1785317234; cv=none; b=Ca3Bu4rYnnxK59+YvHBbhYSm0jYEO2JQHTxzijDZ9EAQw9IlWpAzmT5F7CxAZF2Vg4alIX0/7uiEcPjbJiRNSD/RXKRwa2MEW4rXEHejivUVgGAX4eKga/+EfSUyNxggYfUH3Le8SDGjospJuBUhERVcfr7kIjlD2Shq3ZvxZDg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785317234; c=relaxed/simple; bh=q7xIS+eUoBIC/ATETDyfJeV0KQkuKGU6BfzJ032wwxg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=NurUggrs5q0Bm5gnza231CR5BHT5fDytfaohKSF5vSCLJCmk8nnvsCRVKPd+m5sAfvjwrDOsSipDeEflJM4cMW3s80MZxmI+Pbu33NTQ2Dkt+IPERyc4qq72ihvyNsyY4CoiltpyHiKhnkimtBhaxKoeWE3Ju+Ao/5PQPaj0DbU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=lRGtm4ZG; 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="lRGtm4ZG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8843E1F00A3A; Wed, 29 Jul 2026 09:27:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785317233; bh=nEkM6tHdYvAmijWhRzhBNP+8NQIT97ZMVC9D6UXN+gI=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=lRGtm4ZGd7Di3ehxNoi+3eL7Fgoc1gHNi6kcJKeuVlAvImOajZ9Q6mr3gRJfZII3J xPNBMqf4XMsMHo7FLiqQU+FcA2fBytFdQuJu5fcvqLbhTQNWlSVjhT/pbJemPH96Q+ iTuB1Zg8Y1HI7FuWjR96a68daX9m/tRpvOHefmP6G4ciZtkAE12nFtxthoYlxJmVBK QSBXTu5wjwplFXHTUvLtgW75EmCgA6Sfp5xB4Drgl929hGe0/cdkVXV73WnF+jZTTS wuX7oC+htDdcGVYGrs+lVfKN8y5+QGZbWgjyoDvPQ7etcQuHUpYrp0ZGZ75Nakjs0I pgtPY/0vsDHKw== Message-ID: <49d7454b-b76b-43e7-a359-b2182545dbcc@kernel.org> Date: Wed, 29 Jul 2026 11:27:08 +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 07/13] mm/slab: replace slab.stride with obj_exts_in_object Content-Language: en-US To: Harry Yoo Cc: Suren Baghdasaryan , Hao Li , 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-v3-7-c29ef0f1f257@kernel.org> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/29/26 08:40, Harry Yoo wrote: > On Mon, Jul 27, 2026 at 02:54:01PM +0200, Vlastimil Babka (SUSE) wrote: >> The stride field is used to convert object index to an slabobj_ext so >> both compact arrays (kmalloc() or in-slab-leftover) and spread >> in-object-padding obj_ext layouts are supported. >> >> In practice thus the stride is always sizeof(slabobj_ext) or s->size. >> >> This simplifies the calculations, but with the upcoming slabobj_ext >> handling changes, it will be easier to stop storing the stride and >> instead just have a flag whether obj_ext is in the object padding. >> obj_exts_in_object() can then rely on this flag and slab_obj_ext() >> can use that to determine the stride. >> >> No functional change intended. Performance impact TBD, hopefully >> in the noise. > > Performance impact is not TBD anymore? Ah right, thanks. Since I didn't measure this commit separately, will remove the note completely and leave it to cover letter -> merge commit only. >> Reviewed-by: Suren Baghdasaryan >> Reviewed-by: Hao Li >> Signed-off-by: Vlastimil Babka (SUSE) >> --- > > Looks good to me, > Reviewed-by: Harry Yoo (Oracle) Thanks!