From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) (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 8213114B959 for ; Thu, 26 Sep 2024 15:26:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.185 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727364363; cv=none; b=MCOtdyQg0+NP3jlXyH2kbwWFIel0V8I6R0jDo2Sxtr7f1HsfiGFMpBE7VdqIKZN8HTWsoBMdEzpjZorLsDSm/QYwWnrIMBlJFmvsGBqjFsU/OBhucq5V0DkgzeGpw+X4T689HIbivwME6FtykPQT8pUxE/WKhyCBwGwjlW/uHPk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727364363; c=relaxed/simple; bh=8O97gAQSQMSTIA1LZZJBwR/Vypo4UoHG527XvQ/bhCI=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=UvJlVe/tY75wmemBRWRBgc/nVGU39UR9s3dvpxVpFFqQbWQXXVCRbsoKYEhAHnN+Zfjh573LAGh0Nq8IUeSNY9sriwAOhqQBj1irBVFjLmuOUs0JETRAp/nqo0m00m9AnhyFJsB5XLUof4+uHTLiNyCa80K0hlzD6xIteWGBjo4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=KY4U4I7h; arc=none smtp.client-ip=91.218.175.185 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="KY4U4I7h" Message-ID: <8d19d735-c2a8-456a-ac97-7f8d86cd7ed1@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1727364359; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Z4ZlEW2hvu2WiB0zyG9qp5Yw8aOdRlroBQryAcoNJJ4=; b=KY4U4I7hrDGJSp6YKullSWSD5lP2OkyMVPJoqQhWbnI4jzplUfAvFTcH639OiAiefibyig EzCYgm91vBGkKuRpLuN/KhwHYK/O42gr6CaSUJTQEZAxRtOSKYdnq+NwFp6FmlTkJW++Bd m/OHo6S1IFun6CIEdK6Zrm2+S87b158= Date: Thu, 26 Sep 2024 23:25:33 +0800 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [MAINLINE 0/2] Enable DIM for legacy ULPs and use it in RDS To: Leon Romanovsky Cc: Haakon Bugge , Christoph Hellwig , Jason Gunthorpe , Allison Henderson , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , OFED mailing list , "linux-kernel@vger.kernel.org" , "netdev@vger.kernel.org" , "rds-devel@oss.oracle.com" References: <525e9a31-31ee-4acf-a25c-8bf3a617283f@linux.dev> <1ad540cb-bf1b-456b-be2d-6c35999bdaa8@linux.dev> <66A7418F-4989-4765-AC0F-1D23342C6950@oracle.com> <5b86861b-60f7-4c90-bc0e-d863b422850f@linux.dev> <20240925092645.GD967758@unreal> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Zhu Yanjun In-Reply-To: <20240925092645.GD967758@unreal> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 2024/9/25 17:26, Leon Romanovsky 写道: > On Wed, Sep 25, 2024 at 10:04:21AM +0800, Zhu Yanjun wrote: >> 在 2024/9/24 23:16, Haakon Bugge 写道: >>> >>> >>>> On 24 Sep 2024, at 15:59, Zhu Yanjun wrote: >>>> >>>> 在 2024/9/24 14:54, Christoph Hellwig 写道: >>>>> On Tue, Sep 24, 2024 at 09:58:24AM +0800, Zhu Yanjun wrote: >>>>>> The users that I mentioned is not in the kernel tree. >>>>> And why do you think that would matter the slightest? >>>> >>>> I noticed that the same cq functions are used. And I also made tests with this patch series. Without this patch series, dim mechanism will not be invoked. >>> >>> Christoph alluded to say: Do not modify the old cq_create_cq() code in order to support DIM, it is better to change the ULP to use ib_alloc_cq(), and get DIM enabled that way. >> >> Hi, Haakon >> >> To be honest, I like your original commit that enable DIM for legacy ULPs >> because this can fix this problem once for all and improve the old >> ib_create_cq function. >> >> The idea from Christoph will cause a lot of changes in ULPs. I am not very >> sure if these changes cause risks or not. >> >> Thus, I prefer to your original commit. But I will follow the advice from >> Leon and Jason. > > Christoph was very clear and he summarized our position very well. We > said similar thing to SMC folks in 2022 [1] and RDS is no different here. Thanks, Leon. I will read this link carefully. > > So no, "old ib_create_cq" shouldn't be used by ULPs. Got it. I have replaced ib_create_cq with ib cq pool APIs. Perhaps drivers/infiniband/ulp/srpt/ib_srpt.c is a good example to use ib cq pool APIs. Best Regards, Zhu Yanjun > > Thanks > > [1] https://lore.kernel.org/netdev/YePesYRnrKCh1vFy@unreal/ > >> >> Zhu Yanjun >> >>> >>> >>> Thxs, Håkon >>> >> >>