From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0573EC4360F for ; Fri, 5 Apr 2019 00:04:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CF1E2217D7 for ; Fri, 5 Apr 2019 00:04:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730217AbfDEAEj (ORCPT ); Thu, 4 Apr 2019 20:04:39 -0400 Received: from mga06.intel.com ([134.134.136.31]:58288 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727398AbfDEAEj (ORCPT ); Thu, 4 Apr 2019 20:04:39 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Apr 2019 17:04:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,309,1549958400"; d="asc'?scan'208";a="148177123" Received: from aphull-mobl2.amr.corp.intel.com ([10.251.24.28]) by orsmga002.jf.intel.com with ESMTP; 04 Apr 2019 17:04:38 -0700 Message-ID: <461c66428b411644e78ad5a9a44c47442c9b6edf.camel@intel.com> Subject: Re: [next-queue PATCH v1] igb: Fix limiting the number of queues to number of cpus From: Jeff Kirsher To: Vinicius Costa Gomes , intel-wired-lan@lists.osuosl.org Cc: netdev@vger.kernel.org, Bhagath Singh Karunakaran Date: Thu, 04 Apr 2019 17:04:36 -0700 In-Reply-To: <20190404215632.9881-1-vinicius.gomes@intel.com> References: <20190404215632.9881-1-vinicius.gomes@intel.com> Content-Type: multipart/signed; micalg="pgp-sha512"; protocol="application/pgp-signature"; boundary="=-h87IY61mJ6B9fLD616Qz" User-Agent: Evolution 3.30.5 (3.30.5-1.fc29) MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org --=-h87IY61mJ6B9fLD616Qz Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Thu, 2019-04-04 at 14:56 -0700, Vinicius Costa Gomes wrote: > We have seen some reports[1] of users complaining that they aren't > able to use some queues when their machines have less than 4 cpus. > This affects some TSN workloads, as different traffic classes are > assigned different queues. The current behavior limits the number of > traffic classes that can be reliably handled. >=20 > In practice, what is not working, it returns an invalid parameter > error, in hosts with less than 4 cpus is something like this: >=20 > $ tc qdisc replace dev IFACE parent root mqprio \ > num_tc 3 map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \ > queues 1@0 1@1 2@2 hw 0 >=20 > Because changing the default logic of the allocation of queues could > bring other effects, we propose adding a module parameter so expert > users may override that decision. >=20 > [1] https://github.com/jeez/iproute2/issues/1 >=20 > Reported-by: Bhagath Singh Karunakaran > Signed-off-by: Vinicius Costa Gomes > --- >=20 > A similar fix should also be needed for igc, even if I don't have the > hardware to test, I can produce a patch, if others are able to test. >=20 > I am not totally sure that using a module parameter is the best > solution, so, suggestions are welcome. >=20 > drivers/net/ethernet/intel/igb/igb_main.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) A module parameter maybe fine for our out-of-tree driver, but not for the kernel driver. NACK on the basis that a new module parameter is being introduced for the driver. This is not acceptable by Dave Miller or myself. As of now, I do not have a alternative solution to propose unfortunately. I will discuss the issue with my fellow developers and hopefully we can come up with a kernel interface that all drivers can use to handle this issue. --=-h87IY61mJ6B9fLD616Qz Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part Content-Transfer-Encoding: 7bit -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEiTyZWz+nnTrOJ1LZ5W/vlVpL7c4FAlymm5UACgkQ5W/vlVpL 7c5k/w/8DU9fLsL7nd/hQhwaQUSJRayOPVvnK7GYVa98noog4nTc3mmGNagw7sRu 4/yNOdGwl702GTIbyYS/fOJRK5+4T//xCgq1mSp7WUTHx0NgYYbSWF77mMozR3PF TyM0JHWqWkYPEvGUiTFb32vjpQ/bmf4V3iSgOtUDLCIGISYjFi7xdARuzGhEnoBr NDQ7z2ELNYp7ISO/0nhbNCHAkEQcXFgF/4fJT6fHieIqOno6DaRhzNz/55HptU9J NVDe3GQbdynsYkkhu1R59pQxYCJpQWNKmyaYa6N8sfMGG8KUZytYdxOAuHzzeUIq E7B7gqZxJCUDQouUBLITXIITJay0hw2jUQCFmaIJMAPpsRioDL9gX3AGaICuFgPM U8/fnlB0yR59ZTu2Zf1thin6Diinjb+YmYAWS8v0QGQsa7Id5ETUoZTxU6A6ElXz 03CoKIvMUWdgjCZTuWg5OXS20WO0ibPHiYZbOnOIZg4VgiTDw/PnwtBu/OGPOtSB HmRytZnS6k8E19SDTMGtmhtGlzN2ptojbV89+v5yGUTXXyxawT6St2SJPHxxzSsd AQz0fKOjJzc3xsyBOd0eFWS2UhtaOsLWm7aDNRXpKBoyl0bNp98uUo0+od1RNUk6 Gak0lycxvenxYHf+HT4UsIpyo6V1If87b8x+1vSBm2EeV6T+xpY= =smuc -----END PGP SIGNATURE----- --=-h87IY61mJ6B9fLD616Qz-- From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Kirsher Date: Thu, 04 Apr 2019 17:04:36 -0700 Subject: [Intel-wired-lan] [next-queue PATCH v1] igb: Fix limiting the number of queues to number of cpus In-Reply-To: <20190404215632.9881-1-vinicius.gomes@intel.com> References: <20190404215632.9881-1-vinicius.gomes@intel.com> Message-ID: <461c66428b411644e78ad5a9a44c47442c9b6edf.camel@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: On Thu, 2019-04-04 at 14:56 -0700, Vinicius Costa Gomes wrote: > We have seen some reports[1] of users complaining that they aren't > able to use some queues when their machines have less than 4 cpus. > This affects some TSN workloads, as different traffic classes are > assigned different queues. The current behavior limits the number of > traffic classes that can be reliably handled. > > In practice, what is not working, it returns an invalid parameter > error, in hosts with less than 4 cpus is something like this: > > $ tc qdisc replace dev IFACE parent root mqprio \ > num_tc 3 map 2 2 1 0 2 2 2 2 2 2 2 2 2 2 2 2 \ > queues 1 at 0 1 at 1 2 at 2 hw 0 > > Because changing the default logic of the allocation of queues could > bring other effects, we propose adding a module parameter so expert > users may override that decision. > > [1] https://github.com/jeez/iproute2/issues/1 > > Reported-by: Bhagath Singh Karunakaran > Signed-off-by: Vinicius Costa Gomes > --- > > A similar fix should also be needed for igc, even if I don't have the > hardware to test, I can produce a patch, if others are able to test. > > I am not totally sure that using a module parameter is the best > solution, so, suggestions are welcome. > > drivers/net/ethernet/intel/igb/igb_main.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) A module parameter maybe fine for our out-of-tree driver, but not for the kernel driver. NACK on the basis that a new module parameter is being introduced for the driver. This is not acceptable by Dave Miller or myself. As of now, I do not have a alternative solution to propose unfortunately. I will discuss the issue with my fellow developers and hopefully we can come up with a kernel interface that all drivers can use to handle this issue. -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 833 bytes Desc: This is a digitally signed message part URL: