From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Marchand Subject: Re: [PATCH v4 1/2] mbuf: add function returning default buffer address Date: Fri, 11 Jan 2019 09:11:39 +0100 Message-ID: References: <20190109085426.39965-1-yskoh@mellanox.com> <20190110224030.2671-1-yskoh@mellanox.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Cc: Olivier Matz , Shahaf Shuler , dev@dpdk.org, roszenrami@gmail.com To: Yongseok Koh , Thomas Monjalon Return-path: Received: from mail-vs1-f68.google.com (mail-vs1-f68.google.com [209.85.217.68]) by dpdk.org (Postfix) with ESMTP id 5F2151B946 for ; Fri, 11 Jan 2019 09:11:52 +0100 (CET) Received: by mail-vs1-f68.google.com with SMTP id y27so8736695vsi.1 for ; Fri, 11 Jan 2019 00:11:52 -0800 (PST) In-Reply-To: <20190110224030.2671-1-yskoh@mellanox.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 Thu, Jan 10, 2019 at 11:40 PM Yongseok Koh wrote: > This patch introduces two new functions - rte_mbuf_buf_addr() and > rte_mbuf_data_addr_default(). > > rte_mbuf_buf_addr() reutrns the default buffer address of given mbuf which > returns > comes after mbuf structure and private data. > > rte_mbuf_data_addr_default() returns the default address of mbuf data > taking the headroom into account. > > Signed-off-by: Yongseok Koh > --- > > Please ignore v3, there were errors with some compilers. > > v4: > * fix compilation error due to the experimental tag > * add warning of experimental tag to the comments > > v3: > * rename functions > > v2: > * initial implementation > > lib/librte_mbuf/rte_mbuf.h | 46 > ++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 46 insertions(+) > > diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h > index bc562dc8a9..5787616999 100644 > --- a/lib/librte_mbuf/rte_mbuf.h > +++ b/lib/librte_mbuf/rte_mbuf.h > @@ -788,8 +788,54 @@ rte_mbuf_from_indirect(struct rte_mbuf *mi) > } > > /** > + * Return the default buffer address of the mbuf. > Nit: missed it... s/default // + * > + * @warning > + * @b EXPERIMENTAL: This API may change without prior notice. > + * This will be used by rte_mbuf_to_baddr() which has redundant code once > + * experimental tag is removed. > Good point. I wonder if we have a "todolist" for release n+2 so that we don't forget about such things to do. Thomas ? + * > + * @param mb > + * The pointer to the mbuf. > + * @param mp > + * The pointer to the mempool of the mbuf. > + * @return > + * The pointer of the mbuf buffer. > + */ > +static inline char * __rte_experimental > +rte_mbuf_buf_addr(struct rte_mbuf *mb, struct rte_mempool *mp) > +{ > + char *buffer_addr; > + > + buffer_addr = (char *)mb + sizeof(*mb) + rte_pktmbuf_priv_size(mp); > + return buffer_addr; > +} > Nit: + return (char *)mb + sizeof(*mb) + rte_pktmbuf_priv_size(mp); + > +/** > + * Return the default address of the beginning of the mbuf data. > + * > + * @warning > + * @b EXPERIMENTAL: This API may change without prior notice. > + * > + * @param mb > + * The pointer to the mbuf. > + * @return > + * The pointer of the beginning of the mbuf data. > + */ > +static inline char * __rte_experimental > +rte_mbuf_data_addr_default(struct rte_mbuf *mb) > +{ > + return rte_mbuf_buf_addr(mb, mb->pool) + RTE_PKTMBUF_HEADROOM; > +} > + > +/** > * Return the buffer address embedded in the given mbuf. > * > + * @note: Accessing mempool pointer of a mbuf is expensive because the > + * pointer is stored in the 2nd cache line of mbuf. If mempool is known, > it > + * is better not to reference the mempool pointer in mbuf but calling > + * rte_mbuf_buf_addr() would be more efficient. > + * > * @param md > * The pointer to the mbuf. > * @return > -- > 2.11.0 > > Thanks Yongseok. Reviewed-by: David Marchand -- David Marchand