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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6962CC433FE for ; Tue, 4 Oct 2022 09:52:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229967AbiJDJwG (ORCPT ); Tue, 4 Oct 2022 05:52:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57336 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229914AbiJDJv3 (ORCPT ); Tue, 4 Oct 2022 05:51:29 -0400 Received: from eu-smtp-delivery-151.mimecast.com (eu-smtp-delivery-151.mimecast.com [185.58.86.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1B58B14086 for ; Tue, 4 Oct 2022 02:50:28 -0700 (PDT) Received: from AcuMS.aculab.com (156.67.243.121 [156.67.243.121]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id uk-mta-255-MG7cYJhuPgCC3BXGXVgJRg-1; Tue, 04 Oct 2022 10:50:25 +0100 X-MC-Unique: MG7cYJhuPgCC3BXGXVgJRg-1 Received: from AcuMS.Aculab.com (10.202.163.4) by AcuMS.aculab.com (10.202.163.4) with Microsoft SMTP Server (TLS) id 15.0.1497.38; Tue, 4 Oct 2022 10:50:23 +0100 Received: from AcuMS.Aculab.com ([::1]) by AcuMS.aculab.com ([::1]) with mapi id 15.00.1497.040; Tue, 4 Oct 2022 10:50:23 +0100 From: David Laight To: 'John Stultz' , Qais Yousef CC: LKML , Connor O'Brien , John Dias , Rick Yiu , John Kacur , Chris Redpath , "Abhijeet Dharmapurikar" , Peter Zijlstra , Ingo Molnar , Juri Lelli , "Vincent Guittot" , Dietmar Eggemann , Steven Rostedt , "Thomas Gleixner" , "kernel-team@android.com" , "J . Avila" Subject: RE: [RFC PATCH v3 2/3] sched: Avoid placing RT threads on cores handling long softirqs Thread-Topic: [RFC PATCH v3 2/3] sched: Avoid placing RT threads on cores handling long softirqs Thread-Index: AQHY10jsHNFiDQffOUaXThhlaEqTKa39+a/w Date: Tue, 4 Oct 2022 09:50:23 +0000 Message-ID: References: <20220921012550.3288570-1-jstultz@google.com> <20220921012550.3288570-3-jstultz@google.com> <20220928125517.ei64pxfucaem55cr@wubuntu> In-Reply-To: Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: base64 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org RnJvbTogSm9obiBTdHVsdHoNCj4gU2VudDogMDMgT2N0b2JlciAyMDIyIDE3OjU1DQo+IA0KPiBP biBXZWQsIFNlcCAyOCwgMjAyMiBhdCA1OjU1IEFNIFFhaXMgWW91c2VmIDxxYWlzLnlvdXNlZkBh cm0uY29tPiB3cm90ZToNCj4gPiBPbiAwOS8yMS8yMiAwMToyNSwgSm9obiBTdHVsdHogd3JvdGU6 DQo+ID4gPiBkaWZmIC0tZ2l0IGEvaW5jbHVkZS9saW51eC9pbnRlcnJ1cHQuaCBiL2luY2x1ZGUv bGludXgvaW50ZXJydXB0LmgNCj4gPiA+IGluZGV4IGE3NDlhODY2Mzg0MS4uMWQxMjZiODQ5NWJj IDEwMDY0NA0KPiA+ID4gLS0tIGEvaW5jbHVkZS9saW51eC9pbnRlcnJ1cHQuaA0KPiA+ID4gKysr IGIvaW5jbHVkZS9saW51eC9pbnRlcnJ1cHQuaA0KPiA+ID4gQEAgLTU4Miw2ICs1ODIsMTIgQEAg ZW51bQ0KPiA+ID4gICAqIF8gSVJRX1BPTEw6IGlycV9wb2xsX2NwdV9kZWFkKCkgbWlncmF0ZXMg dGhlIHF1ZXVlDQo+ID4gPiAgICovDQo+ID4gPiAgI2RlZmluZSBTT0ZUSVJRX0hPVFBMVUdfU0FG RV9NQVNLIChCSVQoUkNVX1NPRlRJUlEpIHwgQklUKElSUV9QT0xMX1NPRlRJUlEpKQ0KPiA+ID4g Ky8qIFNvZnRpcnEncyB3aGVyZSB0aGUgaGFuZGxpbmcgbWlnaHQgYmUgbG9uZzogKi8NCj4gPiA+ ICsjZGVmaW5lIExPTkdfU09GVElSUV9NQVNLICgoMSA8PCBORVRfVFhfU09GVElSUSkgICAgICAg fCBcDQo+ID4gPiArICAgICAgICAgICAgICAgICAgICAgICAgKDEgPDwgTkVUX1JYX1NPRlRJUlEp ICAgICAgIHwgXA0KPiA+ID4gKyAgICAgICAgICAgICAgICAgICAgICAgICgxIDw8IEJMT0NLX1NP RlRJUlEpICAgICAgICB8IFwNCj4gPiA+ICsgICAgICAgICAgICAgICAgICAgICAgICAoMSA8PCBJ UlFfUE9MTF9TT0ZUSVJRKSB8IFwNCj4gPiA+ICsgICAgICAgICAgICAgICAgICAgICAgICAoMSA8 PCBUQVNLTEVUX1NPRlRJUlEpKQ0KPiA+DQo+ID4gSSdtIG5vdCBzdXJlIGFib3V0IHRoZSBUQVNL TEVULiBJIGNhbiB1bmRlcnN0YW5kIE5FVCBhbmQgQkxPQ0sgcmVxdWlyZSBoaWdoDQo+ID4gdGhy b3VnaHB1dCwgaGVuY2UgY291bGQgZW5kIHVwIGluIHNvZnRpcnEgZm9yIGEgbG9uZyB0aW1lLiBC dXQgVEFTS0xFVCBzZWVtcw0KPiA+IGFsbG93aW5nIHNsb3BwaW5lc3MuIEkgZG9uJ3QgZmVlbCBz dHJvbmdseSBhYm91dCBpdCwgYnV0IHdvcnRoIGRlYmF0aW5nIGlmIHdlDQo+ID4gcmVhbGx5IG5l ZWQgdG8gaW5jbHVkZSBpdC4NCj4gDQo+IFRoYXQncyBmYWlyLiBEaWdnaW5nIHRocm91Z2ggdGhl IHBhdGNoIGhpc3RvcnkgaW4gdGhlIEFuZHJvaWQgdHJlZXMsDQo+IHRoZSBmaXJzdCBwYXNzIHdh cyBmb3IgYWxsIHNvZnRpcnFzIGJ1dCB0aGVuIHJlc3RyaWN0ZWQgdG8gcmVtb3ZlDQo+IGtub3du IHNob3J0LXJ1bm5pbmcgb25lcy4NCj4gRnJvbSB0aGUgYnVnIGhpc3RvcnkgYW5kIHdoYXQgSSBj YW4gZGlyZWN0bHkgcmVwcm9kdWNlLCB0aGUgbmV0IGFuZA0KPiBibG9jayBzb2Z0aXJxcyBoYXZl IGRlZmluaXRlbHkgY2F1c2VkIHRyb3VibGUsIGJ1dCBJIGRvbid0IHNlZSBhDQo+IHNwZWNpZmlj IGV4YW1wbGUgZnJvbSBUQVNLTEVULCAgc28gSSdtIG9rIGRyb3BwaW5nIHRoYXQgZm9yIG5vdywg YW5kDQo+IHNob3VsZCB3ZSBnZXQgc3BlY2lmaWMgZXZpZGVuY2Ugd2UgY2FuIGFyZ3VlIGZvciBp dCBpbiBhIGZ1dHVyZSBwYXRjaC4NCj4gDQo+IFNvIEknbGwgZHJvcCBUQVNLTEVUIGZyb20gdGhl IGxpc3QgaGVyZS4gVGhhbmtzIGZvciB0aGUgc3VnZ2VzdGlvbiENCg0KSSd2ZSBhbHNvIHNlZW4g dGhlIGNvZGUgdGhhdCBmaW5hbGx5IGZyZWVzIG1lbW9yeSBmcmVlZCB1bmRlciByY3UNCnRha2Ug YSBsb25nIHRpbWUuDQpUaGF0IHdhcyBhIHdvcmtsb2FkIHNlbmRpbmcgYSBsb3Qgb2YgVURQL1JU UCBmcm9tIGEgcmF3IHNvY2tldCB1c2luZw0KSVBfSERSSU5DIC0gZWFjaCBzZW5kIGFsbG9jYXRl ZCBhIHN0cnVjdHVyZSAoZmliPykgdGhhdCB3YXMgZnJlZWQgZnJvbQ0KdGhlIHJjdSAodGltZXI/ KSBzb2Z0aW50IGNhbGxiYWNrLg0KDQpCdXQsIGFjdHVhbGx5LCBvbmUgb2YgdGhlIGJpZ2dlc3Qg Y2F1c2VzIG9mIFJUIHdha2V1cCBsYXRlbmN5DQp3YXMgYSBub3JtYWwgdGhyZWFkIGxvb3Bpbmcg d2l0aG91dCBhIGNvbmRfcmVzY2hlZCgpIGNhbGwuDQpJbiBteSBjYXNlIHNvbWUgZ3JhcGhpY3Mg ZHJpdmVyIGRvaW5nIHBhZ2UgZmx1c2hlcyBvZiB0aGUNCmRpc3BsYXkgbWVtb3J5Lg0KDQouLi4N Cj4gPiA+ICAgICAgICAgICAgICAgaW50IHRhcmdldCA9IGZpbmRfbG93ZXN0X3JxKHApOw0KPiA+ ID4gQEAgLTE2NTYsMTEgKzE2OTksMTQgQEAgc2VsZWN0X3Rhc2tfcnFfcnQoc3RydWN0IHRhc2tf c3RydWN0ICpwLCBpbnQgY3B1LCBpbnQgZmxhZ3MpDQo+ID4gPiAgICAgICAgICAgICAgICAgICAg ICAgZ290byBvdXRfdW5sb2NrOw0KPiA+ID4NCj4gPiA+ICAgICAgICAgICAgICAgLyoNCj4gPiA+ IC0gICAgICAgICAgICAgICogRG9uJ3QgYm90aGVyIG1vdmluZyBpdCBpZiB0aGUgZGVzdGluYXRp b24gQ1BVIGlzDQo+ID4gPiArICAgICAgICAgICAgICAqIElmIGNwdSBpcyBub24tcHJlZW1wdGli bGUsIHByZWZlciByZW1vdGUgY3B1DQo+ID4gPiArICAgICAgICAgICAgICAqIGV2ZW4gaWYgaXQn cyBydW5uaW5nIGEgaGlnaGVyLXByaW8gdGFzay4NCj4gPiA+ICsgICAgICAgICAgICAgICogT3Ro ZXJ3aXNlOiBEb24ndCBib3RoZXIgbW92aW5nIGl0IGlmIHRoZSBkZXN0aW5hdGlvbiBDUFUgaXMN Cj4gPiA+ICAgICAgICAgICAgICAgICogbm90IHJ1bm5pbmcgYSBsb3dlciBwcmlvcml0eSB0YXNr Lg0KPiA+ID4gICAgICAgICAgICAgICAgKi8NCj4gPiA+ICAgICAgICAgICAgICAgaWYgKHRhcmdl dCAhPSAtMSAmJg0KPiA+ID4gLSAgICAgICAgICAgICAgICAgcC0+cHJpbyA8IGNwdV9ycSh0YXJn ZXQpLT5ydC5oaWdoZXN0X3ByaW8uY3VycikNCj4gPiA+ICsgICAgICAgICAgICAgICAgIChtYXlf bm90X3ByZWVtcHQgfHwNCj4gPiA+ICsgICAgICAgICAgICAgICAgICBwLT5wcmlvIDwgY3B1X3Jx KHRhcmdldCktPnJ0LmhpZ2hlc3RfcHJpby5jdXJyKSkNCj4gPiA+ICAgICAgICAgICAgICAgICAg ICAgICBjcHUgPSB0YXJnZXQ7DQo+ID4NCj4gPiBJJ20gbm90IHN1cmUgdGhpcyBtYWtlcyBzZW5z ZS4gWW91IGFzc3VtZSBhIGhpZ2hlciBwcmlvcml0eSB0YXNrIHdpbGwgY2F1c2UNCj4gPiBsZXNz IGRlbGF5IHRoYW4gc29mdGlycXMuIFdoaWNoIEkgdGhpbmsgaXMgYW4gb3B0aW1pc3RpYyBhc3N1 bXB0aW9uPw0KPiA+DQo+ID4gSSB0aGluayB3ZSBzaG91bGQganVzdCBtaW1pYyB0aGUgc2FtZSBm YWxsYmFjayBiZWhhdmlvciB3aGVuIHdlIGZhaWwgdG8gZmluZA0KPiA+IGEgQ1BVIHRoYXQgZml0 cyB0aGUgY2FwYWNpdHkgcmVxdWlyZW1lbnQuIEtlZXBzIHRoaW5ncyBtb3JlIGNvbnNpc3RlbnQg SU1PLg0KPiANCj4gVGhpcyBzb3VuZHMgcmVhc29uYWJsZS4gIEkgZG8gZnJldCB0aGF0IGxvbmct cnVubmluZyBydCB0YXNrcyBhcmUgbGVzcw0KPiBjb21tb24gdGhlbiB0aGUgbG9uZyBydW5uaW5n IHNvZnRpcnFzLCBzbyB0aGlzIG1heSBoYXZlIGFuIGltcGFjdCB0bw0KPiB0aGUgZWZmZWN0aXZl bmVzcyBvZiB0aGUgcGF0Y2gsIGJ1dCBJIGFsc28gc3VzcGVjdCBpdCdzIGV2ZW4gbW9yZSByYXJl DQo+IHRvIGhhdmUgYWxsIHRoZSBvdGhlciBjcHVzIGJ1c3kgd2l0aCBydCB0YXNrcywgc28gaXRz IHByb2JhYmx5IHZlcnkNCj4gdW5saWtlbHkuDQoNCkkndmUgYSB3b3JrbG9hZCB0aGF0IGlzIHZl cnkgbXVjaCBsaWtlIHRoYXQgOi0pDQpUaGUgc2FtZSBSVFAgYXVkaW8gcHJvZ3JhbS4NClJ1bm5p bmcgMzUgUlQgdGhyZWFkcyAob24gNDAgY3B1KSB0aGF0IGFsbCBtaWdodCBydW4gZm9yDQo5bXMg aW4gZXZlcnkgMTBtcy4NClRoZSBvdGhlciA1IGNwdSBtaWdodCBhbHNvIGJlIHJ1bm5pbmcgUlQg dGhyZWFkcyBzaW5jZSBJDQpoYXZlIHRvIHVzZSB0aHJlYWRlZCBOQVBJIGFuZCBtYWtlIHRoZSBO QVBJIHRocmVhZHMgUlQNCmluIG9yZGVyIHRvIGF2b2lkIGRyb3BwaW5nIHBhY2tldHMuDQpNb3N0 IG9mIHRoZSB3YWtldXBzIGNhbiBqdXN0IHdhaXQgZm9yIHRoZSBwcmV2aW91cyBjcHUNCnRvIGJl Y29tZSBhdmFpbGFibGUsIG9ubHkgdGhlIHNsZWVwIG9uIGEgaGlnaC1yZXMgdGltZXINCndvdWxk IGJlbmVmaXQgZnJvbSBjaGFuZ2luZyB0aGUgY3B1Lg0KDQpUaGUgcmVhbCBzY2hlZHVsaW5nIHBy b2JsZW0gd2Fzbid0IGFjdHVhbGx5IHdha2V1cHMgYXQgYWxsLg0KVGhlIHByb2JsZW0gaXMgdGhl IHNvZnRpbnQgY29kZSBydW5uaW5nIHdoaWxlIHRoZSBSVCB0aHJlYWQNCmhlbGQgYSBjdiAtIHdo aWNoIHN0b3BwZWQgYWxsIHRoZSBvdGhlciB0aHJlYWRzIGluIHRoZWlyDQp0cmFja3MuDQpJIGhh ZCB0byByZXBsYWNlIGFsbCB0aGUgJ2hvdCcgY3Ygd2l0aCBhdG9taWMgb3BlcmF0aW9ucy4NCg0K VGhlIG9ubHkgJ3dha2V1cCcgcHJvYmxlbSBJIGhhZCB3YXMgdGhhdCBjdl9icm9hZGNhc3QoKSB3 b2tlDQplYWNoIFJUIHRhc2sgaW4gdHVybiAtIHNvIGlmIG9uZSB3YWl0ZWQgZm9yIHRoZSBzb2Z0 aW50IGNvZGUNCnRvIGZpbmlzaCB0aGVuIHNvIHdvdWxkIGFsbCB0aGUgcmVzdC4NCihGaXhlZCBi eSB1c2luZyBhIHNlcGFyYXRlIGN2IGZvciBlYWNoIHRocmVhZC4pDQoNCglEYXZpZA0KDQotDQpS ZWdpc3RlcmVkIEFkZHJlc3MgTGFrZXNpZGUsIEJyYW1sZXkgUm9hZCwgTW91bnQgRmFybSwgTWls dG9uIEtleW5lcywgTUsxIDFQVCwgVUsNClJlZ2lzdHJhdGlvbiBObzogMTM5NzM4NiAoV2FsZXMp DQo=