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 291F03783AF; Wed, 27 May 2026 09:38:27 +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=1779874712; cv=none; b=MysC2jQJ34MBzE3FJu6CCeH8wYY4scxPJr6HloU4yLEUIxSuEjeb7eTlrFbBklDPP9/Qr9+kR6/1yH4IqwUOXqIbukhclx4BGwHQjWdj8Fsa7rCVUTuQf34hb57OYEFqLxVcDNJJT3O8EHuRQoGdbqQCuUJuwGrMO2ddCQkhpH0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779874712; c=relaxed/simple; bh=6qZqFcxUhtLffjqo4KyIWK1FZl81UuCOmaM2W18nhxo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=n/Ny6VOrpjqO45RWryhtf3kP9dMhBFakx2Qo0LlP/frNjN1ZhqIu+SBphv3XgHS+VkXVzZraVWbRCzGHudpeCm2xUbGlpRh1W84dl2mwi+oAQJGg/e3wgbZkYokG0eCRDIvnkOycDMHZjyoNET28QUo871Du2dFOTH2QJxSu0T4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fr7UQCUm; 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="fr7UQCUm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4D8211F000E9; Wed, 27 May 2026 09:38:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779874706; bh=5EPgL4FAe9Q1HpUW4tud1I2dVamBDFhNI1A3ygm0Wgw=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=fr7UQCUm5cprOrQGU5TbDClX+R7dEqRJjoGjS0k5gjydzKuG1ACoNftI/UA+F9ZYV kUAjPhUGoVpcUj8H4cLZ00oBUZK5oxIBiyuxLccRqsuZPv8L6vnbNO6e5AbFUsmP9O hRwUh+bWssxFUwT9RMOkWFh8U0sQ6pY/o6w/hkJRkSaESagT8LptRA8x3Y6kR6O2Z/ BryXQg098y6OJ9ZI3SMWHBpn8H0MU7+hO95viQNGdondhORmhsxy0aY1XgSfmfWjVo LgyOBf7KaZ/RLeZLaociiRSH30fkZbJGbXxZVcFCRxRM/JvjIbfEYFdTcCXGWYVypC Mhd7NZs0NEfyQ== Message-ID: Date: Wed, 27 May 2026 11:38:21 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm/slab: improve kmem_cache_alloc_bulk Content-Language: en-US To: Christoph Hellwig , Harry Yoo , Andrew Morton Cc: Hao Li , Christoph Lameter , David Rientjes , Roman Gushchin , Jesper Dangaard Brouer , linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, io-uring@vger.kernel.org, kasan-dev@googlegroups.com, bpf@vger.kernel.org, netdev@vger.kernel.org References: <20260527070239.2252948-1-hch@lst.de> <20260527070239.2252948-2-hch@lst.de> From: "Vlastimil Babka (SUSE)" Autocrypt: addr=vbabka@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 5/27/26 09:02, Christoph Hellwig wrote: > The kmem_cache_alloc_bulk return value is weird. It returns the number > of allocated objects, but that must always be 0 or the requested number > based on the implementations and the handling in the callers, but that > assumption is not actually documented anywhere, which confuses automated > review tools. > > Fix this by returning a bool if the allocation succeeded and adding a > kerneldoc comment explaining the API. > > Signed-off-by: Christoph Hellwig Would 0 / -ENOMEM be more like what people would expect? I guess both that and bool are better than the current API.