From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ferruh Yigit Subject: Re: [PATCH] net/mlx5: fix Tx doorbell Date: Thu, 5 Jan 2017 18:17:06 +0000 Message-ID: <92aca8e0-302b-731d-0cba-36e6297f17a6@intel.com> References: <1481290078-4530-1-git-send-email-nelio.laranjeiro@6wind.com> <2da35386-f774-a1ca-c4f2-cc77f74f6e2c@intel.com> <20170105163226.GP12822@6wind.com> <20170105165223.GQ12822@6wind.com> <20170105181212.GR12822@6wind.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: Nelio Laranjeiro , dev@dpdk.org To: Adrien Mazarguil Return-path: Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id 4670329CF for ; Thu, 5 Jan 2017 19:17:09 +0100 (CET) In-Reply-To: <20170105181212.GR12822@6wind.com> 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 1/5/2017 6:12 PM, Adrien Mazarguil wrote: > On Thu, Jan 05, 2017 at 05:01:27PM +0000, Ferruh Yigit wrote: >> On 1/5/2017 4:52 PM, Adrien Mazarguil wrote: >>> On Thu, Jan 05, 2017 at 05:32:26PM +0100, Adrien Mazarguil wrote: >>>> Hi Ferruh, >>>> >>>> On Thu, Jan 05, 2017 at 03:19:35PM +0000, Ferruh Yigit wrote: >>>>> On 12/9/2016 1:27 PM, Nelio Laranjeiro wrote: >>>>>> Too much data is uselessly written to the Tx doorbell. >>>>>> >>>>>> Fixes: 1d88ba171942 ("net/mlx5: refactor Tx data path") >>>>>> >>>>>> Signed-off-by: Nelio Laranjeiro >>>>>> Acked-by: Adrien Mazarguil >>>>>> >>>>> >>>>> Applied to dpdk-next-net/master, thanks. >>>>> >>>>> Is not CC'ing stable intentional, since this patch depends on a patch >>>>> introduced in this release? If not intentional, please CC stable. >>>> >>>> I intended to update the commit message for this patch as in the meantime we >>>> discovered it addresses a significant regression introduced in v16.11. >>>> >>>> CC'ing stable now. >>>> >>>> If possible, can you amend the commit log with: >>>> >>>> --- >>>> >>>> net/mlx5: fix Tx doorbell >>>> >>>> Too much data is uselessly written to the Tx doorbell, which since v16.11 >>>> may also cause Tx queues to behave erratically and crash applications. >>>> >>>> This regression was seen on VF devices when the BlueFlame buffer size is >>>> zero (txq->cqe_n == 0) due to the following change: >>>> >>>> - cqe = &(*txq->cqes)[ci & (txq->cqe_n - 1)].cqe64; >>>> + cqe = &(*txq->cqes)[ci & ((1 << txq->cqe_n) - 1)]; >>>> >>>> Fixes: 1d88ba171942 ("net/mlx5: refactor Tx data path") >>>> Fixes: e2f116ee3cac ("net/mlx5: reduce memory overhead for CQE handling") >>>> >>>> Signed-off-by: Nelio Laranjeiro >>>> Acked-by: Adrien Mazarguil >>>> Cc: stable@dpdk.org >>>> >>>> --- >>> >>> I mixed the commit that introduced the regression with a similar looking yet >>> harmless one, here is the proper message to use, sorry for the noise: >>> >>> --- >>> >>> net/mlx5: fix Tx doorbell >>> >>> Too much data is uselessly written to the Tx doorbell, which since v16.11 >>> may also cause Tx queues to behave erratically and crash applications. >>> >>> This regression was seen on VF devices when the BlueFlame buffer size is >>> zero (txq->bf_buf_size) due to the following change: >>> >>> - txq->bf_offset ^= txq->bf_buf_size; >>> + txq->bf_offset ^= (1 << txq->bf_buf_size); >>> >>> Fixes: 1d88ba171942 ("net/mlx5: refactor Tx data path") >>> Fixes: d5793daefec8 ("net/mlx5: reduce memory overhead for BF handling") >>> >>> Signed-off-by: Nelio Laranjeiro >>> Acked-by: Adrien Mazarguil >>> Cc: stable@dpdk.org >>> >>> --- >>> >> >> Can you please confirm commit in latest next-net? > > Not sure if the "Cc: stable@dpdk.org" line should have been kept, No, we are removing it from the commit. It is useful in the patch since "git send-email" ensures the stable mail list is added into CC. But it is not that useful in the git history. > otherwise it's perfect, thanks Ferruh! OK, thanks. >