From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Monjalon Subject: Re: [dpdk-stable] [PATCH v2 2/2] eal: restrict ctrl threads to startup cpu affinity Date: Tue, 19 Feb 2019 17:03:03 +0100 Message-ID: <4081676.pH4rpHE09Y@xps> References: <1550074412-31285-1-git-send-email-david.marchand@redhat.com> <6d3960bc-9798-fa79-2538-339d63caf81b@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Cc: stable@dpdk.org, dev@dpdk.org, Olivier Matz , Kevin Traynor To: David Marchand , "Burakov, Anatoly" Return-path: 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" 19/02/2019 12:51, David Marchand: > On Tue, Feb 19, 2019 at 12:38 PM Burakov, Anatoly > wrote: > > On 14-Feb-19 1:30 PM, David Marchand wrote: > > > --- a/doc/guides/prog_guide/env_abstraction_layer.rst > > > +++ b/doc/guides/prog_guide/env_abstraction_layer.rst > > > +Control Thread API > > > +~~~~~~~~~~~~~~~~~~ > > > + > > > +It is possible to create Control Threads using the public API > > ``rte_ctrl_thread_create()``. > > > +Those threads can be used for management/infrastructure tasks and are > > used internally by DPDK for multi process support and interrupt handling. > > > + > > > +Those threads will be scheduled on cpus part of the original process > > cpu affinity from which the dataplane and service lcores are excluded. > > > + > > > +For example, on a 8 cpus system, starting a dpdk application with -l > > 2,3 (dataplane cores), then depending on the affinity configuration which > > can be controlled with tools like taskset (Linux) or cpuset (FreeBSD), > > > + > > > +- with no affinity configuration, the Control Threads will end up on > > 0-1,4-7 cpus. > > > +- with affinity restricted to 2-4, the Control Threads will end up on > > cpu 4. > > > +- with affinity restricted to 2-3, the Control Threads will end up on > > cpu 2 (master lcore, which is the default when no cpu is available). > > > > You're not winning anything by foregoing the 80 char limit on > > documentation (doxygen will still generate this correctly), but you're > > losing in readability when working in terminal. I would prefer if you > > didn't do those long lines :) > > I don't really care, I will just wait for Thomas opinion. > > > Thomas, do we want checkpatch to warn about this? http://doc.dpdk.org/guides/contributing/documentation.html#line-length Lines should not exceed 80 chars. There is a tradition of being very flexible in docs. The best is to wrap at the end of a logical group of words, like after commas or dots. So the doc updates patches are easier to read.