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 68AC42877DA; Wed, 29 Jul 2026 06:41:00 +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=1785307261; cv=none; b=TloZINfxKNIM9sxiY5A9YCywn6PVK3tlZqUpYBAp4xga+7zf8tQZuThKqkyqMUf2x68Plu+jqx3Y3mvmSobEtQ1rtM8m1iL4NhSlhoID+6IQFEb7V+OHOwpGgEi0JK1iEUU5fFloUzkzcDBP5bPhvZ2MLLwMvnyHMfl0PC+3kYQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785307261; c=relaxed/simple; bh=Gjr+SPEN/khoSfSsCZZAaZFy1cjB7tcQFOXmwxDkf9c=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UWXujnJP4M97aLLSmT5C3/L6xrlgZJ05ueyCUfCKOhCHl8x7h99TB+B1bsb9/vFj+V8PyjP2O2wo4B55XrqUYLBPjNlw2gBsS0XFuRGleyN7ydEhtZAY2qRR9XNBvsQEpsZfJLfQSt2YRtYDReFShGbFGiGd73moVmKUi5u4D2w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=h/0JUvwr; 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="h/0JUvwr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 67C3E1F000E9; Wed, 29 Jul 2026 06:40:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785307259; bh=aJ+OYo0jt+7rELKxSKj63C782hUiaz6ZZJLz2l3U6Os=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=h/0JUvwrqc9fADdYseINnuUR81h0pXXKxeyvG4vnTsM35njoUbwZSEWo09fw0WCpN h+tgKdMHVHw3x6r/HjuZnAC+ELyh2JJzhDRGjSJU2omixz7cX4r3bQAwy/S4ldY2le ReLMjgqoU6252ken+TyS1q/mANDObeevQS33DrY0K8bfkPEEld0y9pSweCadeKStvO M/VADi1/oYAAft8yswpZc6KQwI1ECNYcDQSiwEqqIsavRlWGJ8JwJSTQnV5WFxRX1q SbxrxW+VhZ78tPB52sv8Q2yFuw9RwG3/mrD2ddNazOX3YPbhH/f33XG9OsmxX5jCPu XDpe4tQrka7RQ== Date: Wed, 29 Jul 2026 06:40:57 +0000 From: Harry Yoo To: "Vlastimil Babka (SUSE)" 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 Subject: Re: [PATCH v3 07/13] mm/slab: replace slab.stride with obj_exts_in_object Message-ID: References: <20260727-b4-objext_split-v3-0-c29ef0f1f257@kernel.org> <20260727-b4-objext_split-v3-7-c29ef0f1f257@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: <20260727-b4-objext_split-v3-7-c29ef0f1f257@kernel.org> 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? > Reviewed-by: Suren Baghdasaryan > Reviewed-by: Hao Li > Signed-off-by: Vlastimil Babka (SUSE) > --- Looks good to me, Reviewed-by: Harry Yoo (Oracle)