From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.droids-corp.org (zoll.droids-corp.org [94.23.50.67]) by dpdk.org (Postfix) with ESMTP id DF9358DA0 for ; Wed, 25 Apr 2018 22:00:17 +0200 (CEST) Received: from [37.173.100.35] (helo=droids-corp.org) by mail.droids-corp.org with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1fBQaQ-0000QY-UG; Wed, 25 Apr 2018 22:00:20 +0200 Received: by droids-corp.org (sSMTP sendmail emulation); Wed, 25 Apr 2018 22:00:10 +0200 Date: Wed, 25 Apr 2018 22:00:10 +0200 From: Olivier Matz To: Yongseok Koh Cc: Andrew Rybchenko , Wenzhuo Lu , Jingjing Wu , "dev@dpdk.org" , Konstantin Ananyev , Adrien Mazarguil , =?iso-8859-1?Q?N=E9lio?= Laranjeiro Message-ID: <20180425200010.beqchgnm4lboqdp5@neon> References: <20180310012532.15809-1-yskoh@mellanox.com> <20180424013854.33749-1-yskoh@mellanox.com> <934e714e-3cba-7f5d-9fcf-4f96611d758f@solarflare.com> <20180424160244.bggifhilvadxcjb2@neon> <20180425082821.ktbzjrnxbo4nhqgg@neon> <915EB643-1009-4016-9E18-7DAB43FFDC9F@mellanox.com> <22EF1A3B-ECFF-4A4F-955D-43F992B4F135@mellanox.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <22EF1A3B-ECFF-4A4F-955D-43F992B4F135@mellanox.com> User-Agent: NeoMutt/20170113 (1.7.2) Subject: Re: [dpdk-dev] [PATCH v4 1/2] mbuf: support attaching external buffer to mbuf X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 25 Apr 2018 20:00:18 -0000 On Wed, Apr 25, 2018 at 09:19:32AM +0000, Yongseok Koh wrote: > > On Apr 25, 2018, at 2:08 AM, Yongseok Koh wrote: > >> On Apr 25, 2018, at 1:28 AM, Olivier Matz wrote: > >> > >> Hi Yongseok, > >> > >> On Tue, Apr 24, 2018 at 06:02:44PM +0200, Olivier Matz wrote: > >>>>> @@ -688,14 +704,33 @@ rte_mbuf_to_baddr(struct rte_mbuf *md) > >>>>> } > >>>>> /** > >>>>> + * Returns TRUE if given mbuf is cloned by mbuf indirection, or FALSE > >>>>> + * otherwise. > >>>>> + * > >>>>> + * If a mbuf has its data in another mbuf and references it by mbuf > >>>>> + * indirection, this mbuf can be defined as a cloned mbuf. > >>>>> + */ > >>>>> +#define RTE_MBUF_CLONED(mb) ((mb)->ol_flags & IND_ATTACHED_MBUF) > >>>>> + > >>>>> +/** > >>>>> * Returns TRUE if given mbuf is indirect, or FALSE otherwise. > >>>>> */ > >>>>> -#define RTE_MBUF_INDIRECT(mb) ((mb)->ol_flags & IND_ATTACHED_MBUF) > >>>>> +#define RTE_MBUF_INDIRECT(mb) RTE_MBUF_CLONED(mb) > >>>> > >>>> It is still confusing that INDIRECT != !DIRECT. > >>>> May be we have no good options right now, but I'd suggest to at least > >>>> deprecate > >>>> RTE_MBUF_INDIRECT() and completely remove it in the next release. > >>> > >>> Agree. I may have missed something, but is my previous suggestion > >>> not doable? > >>> > >>> - direct = embeds its own data (and indirect = !direct) > >>> - clone (or another name) = data is another mbuf > >>> - extbuf = data is in an external buffer > >> > >> Any comment about this option? > > > > I liked your idea, so I defined RTE_MBUF_CLONED() and wanted to deprecate > > RTE_MBUF_INDIRECT() in the coming release. But RTE_MBUF_DIRECT() can't be > > (!RTE_MBUF_INDIRECT()) because it will logically include RTE_MBUF_HAS_EXTBUF(). > > I'm not sure I understand you correctly. > > > > Can you please give me more guidelines so that I can take you idea? > > Maybe, did you mean the following? Looks like doable but RTE_MBUF_DIRECT() > can't logically mean 'mbuf embeds its own data', right? > > #define RTE_MBUF_INDIRECT(mb) ((mb)->ol_flags & IND_ATTACHED_MBUF) > #define RTE_MBUF_DIRECT(mb) (!RTE_MBUF_INDIRECT(mb)) > > #define RTE_MBUF_HAS_EXTBUF(mb) ((mb)->ol_flags & EXT_ATTACHED_MBUF) > #define RTE_MBUF_CLONED(mb) ((mb)->ol_flags & IND_ATTACHED_MBUF) I was thinking about something like this: #define RTE_MBUF_HAS_EXTBUF(mb) ((mb)->ol_flags & EXT_ATTACHED_MBUF) #define RTE_MBUF_CLONED(mb) ((mb)->ol_flags & IND_ATTACHED_MBUF) #define RTE_MBUF_DIRECT(mb) (!RTE_MBUF_HAS_EXTBUF(mb) && !RTE_MBUF_CLONED(mb)) #define RTE_MBUF_INDIRECT(mb) (!RTE_MBUF_DIRECT(mb))