From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id E6B31A052A; Wed, 27 Jan 2021 15:57:09 +0100 (CET) Received: from [217.70.189.124] (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 5B33D140E24; Wed, 27 Jan 2021 15:57:09 +0100 (CET) Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by mails.dpdk.org (Postfix) with ESMTP id 51162140E23 for ; Wed, 27 Jan 2021 15:57:08 +0100 (CET) IronPort-SDR: hZC7lpmnIYOrXWTG87hz3GuDEa9PNMJgHXhuZN2LDeYvZn05ZAX0/R3tW7fKKChzx1npwoiTE1 jmVVRp+60Kdg== X-IronPort-AV: E=McAfee;i="6000,8403,9877"; a="241606879" X-IronPort-AV: E=Sophos;i="5.79,379,1602572400"; d="scan'208";a="241606879" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Jan 2021 06:57:07 -0800 IronPort-SDR: SyuxlPcfpBGhYtlLcYzLrDYflhBj5apUmIIUuSfh6u6ILLLJYCXXWGMCjMUjK03A6/ax69QpU4 JvkdaiI06soA== X-IronPort-AV: E=Sophos;i="5.79,379,1602572400"; d="scan'208";a="430121985" Received: from fyigit-mobl1.ger.corp.intel.com (HELO [10.213.208.215]) ([10.213.208.215]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Jan 2021 06:57:06 -0800 To: Liron Himi , Jerin Jacob Kollanukkaran Cc: "dev@dpdk.org" References: <20201202101212.4717-1-lironh@marvell.com> <20210122191925.24308-1-lironh@marvell.com> <20210122191925.24308-27-lironh@marvell.com> <78541fad-ec6d-401a-37c8-45df28e942b0@intel.com> <6200e955-7a00-651a-2389-ad3756a8290a@intel.com> From: Ferruh Yigit Message-ID: <8584803a-4993-32ea-b0fd-1d55ef3bdbba@intel.com> Date: Wed, 27 Jan 2021 14:57:02 +0000 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Subject: Re: [dpdk-dev] [EXT] Re: [PATCH v2 26/37] net/mvpp2: introduce fixup for fifo overrun X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" On 1/27/2021 2:46 PM, Liron Himi wrote: > > -----Original Message----- > From: Ferruh Yigit > Sent: Wednesday, 27 January 2021 16:35 > To: Liron Himi ; Jerin Jacob Kollanukkaran > Cc: dev@dpdk.org > Subject: Re: [EXT] Re: [dpdk-dev] [PATCH v2 26/37] net/mvpp2: introduce fixup for fifo overrun > > On 1/27/2021 2:08 PM, Liron Himi wrote: >> >> >> Liron Himi >> Staff Software Engineer >> >> >> >> Park Azorim, Kyriat Arie, Petah Tikva, 49527, Israel >> Mobile: +972.52.3329169 >> >> -----Original Message----- >> From: Ferruh Yigit >> Sent: Wednesday, 27 January 2021 01:50 >> To: Liron Himi ; Jerin Jacob Kollanukkaran >> >> Cc: dev@dpdk.org >> Subject: [EXT] Re: [dpdk-dev] [PATCH v2 26/37] net/mvpp2: introduce >> fixup for fifo overrun >> >> External Email >> >> ---------------------------------------------------------------------- >> On 1/22/2021 7:19 PM, lironh@marvell.com wrote: >>> From: Liron Himi >>> >>> Currently the HW is configured with only one pool which its buffer >>> size may be larger than the rx-fifo-size. >>> In that situation, frame size larger than the fifo-size is gets >>> dropped due to fifo overrun. >>> this is cause because the HW works in cut-through mode which waits to >>> have in the fifo at least the amount of bytes as define in the >>> smallest pool's buffer size. >>> >>> This patch add a dummy pool which its buffer size is very small >>> (smaller than 64B frame). this tricks the HW and any frame size is >>> gets passed from the FIFO to the PP2. >>> >>> Signed-off-by: Liron Himi >> >> so this is fixing the FIFO overrun, can you please provide the fixes line? >> [L.H.] it is kind of combination of HW fifo size (which defined by kernel driver), given buffer size and incoming pkt size. I don't think I can point to a line in DPDK driver code that this patch is fixing. >> it is a kind of WA for a HW issue. >> > > Is HW FIFO size or HW behavior (to wait at least smallest pool's buffer size) changed with recent kernel driver or MUSDK to cause this problem? If so can you please mention/reference that change in the commit log? > [L.H.] I don't think it was related to a change. But this combination was just tested by our QA team. > I think it may have more affect when the buffer size is of 9K which in some cases may exceed the fifo size of a specific port. > OK, thanks for clarification. >> And should this patch backported? >> [L.H.] it cannot be backported as it depends on MUSDK api change. >> > > Is the fix or problem depends on the MUSDK API change? If the fix has a dependency will this be a problem, since it means latest driver won't be usable with old MUSDK version? > Can you please clarify the dependency in the commit log? > [L.H.] I already updated the doc that latest driver (including meson stuff) required new MUSDK version. > > Thanks, > ferruh >