From mboxrd@z Thu Jan 1 00:00:00 1970 From: Olivier Matz Subject: Re: [RFC] mbuf: new flag when vlan is stripped Date: Mon, 23 May 2016 09:59:56 +0200 Message-ID: <5742B87C.5070308@6wind.com> References: <57222193.2040907@6wind.com> <1462897493-6567-1-git-send-email-olivier.matz@6wind.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: "konstantin.ananyev@intel.com" , "helin.zhang@intel.com" , "adrien.mazarguil@6wind.com" , "rahul.lakkireddy@chelsio.com" , "alejandro.lucero@netronome.com" , "sony.chacko@qlogic.com" To: "John Daley (johndale)" , "dev@dpdk.org" Return-path: Received: from mail.droids-corp.org (zoll.droids-corp.org [94.23.50.67]) by dpdk.org (Postfix) with ESMTP id 1A1AE66DA for ; Mon, 23 May 2016 10:00:13 +0200 (CEST) In-Reply-To: List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Hi John, On 05/12/2016 10:36 PM, John Daley (johndale) wrote: >> ... This is a draft patch that implements what was previously >> discussed, except the packet_type, which does not exist for vlan >> today (and I think it is not mandatory for now, let's do it in >> another patch). >> >> After doing this patch, it appeared that ixgbe was the only driver >> that had a different behavior for the PKT_RX_VLAN_PKT flag. An >> alternative to this patch would be to only change the behavior of >> the ixgbe driver, and just document better document the >> PKT_RX_VLAN_PKT flags in rte_mbuf.h without adding new flags. I >> think this is a better option. >> >> Comments are welcome. >> > There are applications depending on the current behavior of > PKT_RX_VLAN_PKT as confusing as it may be. I know of one that has > VLAN stripping disabled and uses the flag to determine if the packet > delivered to the app has a VLAN tag. This is actually how the flag > behaves for ixgbe, and they patched enic and maybe other drivers to > act accordingly. To avoid breaking the app (and any others like it), > I think we should keep the flag behavior the same and add the new > flag PKT_RX_VLAN_STRIPPED . OK, thanks for your comment. So it means the v1 will be the same than RFC. I'm submitting it. > We should follow on with the new packet type since it enables a nice > performance improvement by not forcing apps to break open the packet > just to see if there is a VLAN tag. Yep, agree. Thanks, Olivier