From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [PATCH v3 ] ethdev: introduce lock-free txq capability flag Date: Tue, 18 Jul 2017 16:43:55 +0300 Message-ID: <13765612.oLuGorxqyg@xps> References: <20170706062120.3895-1-jerin.jacob@caviumnetworks.com> <20170710165946.31080-1-jerin.jacob@caviumnetworks.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: dev@dpdk.org, Hemant Agrawal , john.mcnamara@intel.com To: Jerin Jacob Return-path: Received: from out1-smtp.messagingengine.com (out1-smtp.messagingengine.com [66.111.4.25]) by dpdk.org (Postfix) with ESMTP id 695413253 for ; Tue, 18 Jul 2017 15:43:58 +0200 (CEST) In-Reply-To: List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" 13/07/2017 15:02, Hemant Agrawal: > On 7/10/2017 10:29 PM, Jerin Jacob wrote: > > Introducing the DEV_TX_OFFLOAD_MT_LOCKFREE TX capability flag. > > if a PMD advertises DEV_TX_OFFLOAD_MT_LOCKFREE capable, multiple threads > > can invoke rte_eth_tx_burst() concurrently on the same tx queue without > > SW lock. This PMD feature will be useful in the following use cases and > > found in the OCTEON family of NPUs. > > > > 1) Remove explicit spinlock in some applications where lcores > > to TX queues are not mapped 1:1. > > example: OVS has such instance > > https://github.com/openvswitch/ovs/blob/master/lib/netdev-dpdk.c#L299 > > https://github.com/openvswitch/ovs/blob/master/lib/netdev-dpdk.c#L1859 > > See the the usage of tx_lock spinlock. > > > > 2) In the eventdev use case, avoid dedicating a separate TX core for > > transmitting and thus enables more scaling as all workers can > > send the packets. > > > > Signed-off-by: Jerin Jacob > > You may also like to add this capability in "doc/guides/nics/features/*.ini" I've just added the feature "Lock-free Tx queue" in features/default.ini. > Acked-by: Hemant Agrawal Applied, thanks