From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f70.google.com (mail-oi0-f70.google.com [209.85.218.70]) by kanga.kvack.org (Postfix) with ESMTP id 3886B6B0003 for ; Wed, 25 Jul 2018 01:02:51 -0400 (EDT) Received: by mail-oi0-f70.google.com with SMTP id m197-v6so6459373oig.18 for ; Tue, 24 Jul 2018 22:02:51 -0700 (PDT) Received: from g4t3425.houston.hpe.com (g4t3425.houston.hpe.com. [15.241.140.78]) by mx.google.com with ESMTPS id u142-v6si3043425oif.412.2018.07.24.22.02.49 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 24 Jul 2018 22:02:49 -0700 (PDT) From: "Elliott, Robert (Persistent Memory)" Subject: RE: [PATCH v2] RFC: clear 1G pages with streaming stores on x86 Date: Wed, 25 Jul 2018 05:02:46 +0000 Message-ID: References: <20180724210923.GA20168@bombadil.infradead.org> <20180725023728.44630-1-cannonmatthews@google.com> In-Reply-To: <20180725023728.44630-1-cannonmatthews@google.com> Content-Language: en-US Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Cannon Matthews , Michal Hocko , Mike Kravetz , Andrew Morton , Matthew Wilcox , "Kirill A. Shutemov" Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Andres Lagar-Cavilla , Salman Qazi , Paul Turner , David Matlack , Peter Feiner , Alain Trinh DQoNCj4gLS0tLS1PcmlnaW5hbCBNZXNzYWdlLS0tLS0NCj4gRnJvbTogbGludXgta2VybmVsLW93 bmVyQHZnZXIua2VybmVsLm9yZyA8bGludXgta2VybmVsLQ0KPiBvd25lckB2Z2VyLmtlcm5lbC5v cmc+IE9uIEJlaGFsZiBPZiBDYW5ub24gTWF0dGhld3MNCj4gU2VudDogVHVlc2RheSwgSnVseSAy NCwgMjAxOCA5OjM3IFBNDQo+IFN1YmplY3Q6IFJlOiBbUEFUQ0ggdjJdIFJGQzogY2xlYXIgMUcg cGFnZXMgd2l0aCBzdHJlYW1pbmcgc3RvcmVzIG9uDQo+IHg4Ng0KPiANCj4gUmVpbXBsZW1lbnQg Y2xlYXJfZ2lnYW50aWNfcGFnZSgpIHRvIGNsZWFyIGdpZ2FieXRlcyBwYWdlcyB1c2luZyB0aGUN Cj4gbm9uLXRlbXBvcmFsIHN0cmVhbWluZyBzdG9yZSBpbnN0cnVjdGlvbnMgdGhhdCBieXBhc3Mg dGhlIGNhY2hlDQo+IChtb3ZudGkpLCBzaW5jZSBhbiBlbnRpcmUgMUdpQiByZWdpb24gd2lsbCBu b3QgZml0IGluIHRoZSBjYWNoZQ0KPiBhbnl3YXkuDQo+DQo+IERvaW5nIGFuIG1sb2NrKCkgb24g YSA1MTJHaUIgMUctaHVnZXRsYiByZWdpb24gcHJldmlvdXNseSB3b3VsZCB0YWtlDQo+IG9uIGF2 ZXJhZ2UgMTM0IHNlY29uZHMsIGFib3V0IDI2MG1zL0dpQiB3aGljaCBpcyBxdWl0ZSBzbG93LiBV c2luZw0KPiBgbW92bnRpYCBhbmQgb3B0aW1pemluZyB0aGUgY29udHJvbCBmbG93IG92ZXIgdGhl IGNvbnN0aXR1ZW50IHNtYWxsDQo+IHBhZ2VzLCB0aGlzIGNhbiBiZSBpbXByb3ZlZCByb3VnaGx5 IGJ5IGEgZmFjdG9yIG9mIDMtNHgsIHdpdGggdGhlDQo+IDUxMkdpQiBtbG9jaygpIHRha2luZyBv bmx5IDM0IHNlY29uZHMgb24gYXZlcmFnZSwgb3IgNjdtcy9HaUIuDQoNCi4uLg0KPiAtIEFyZSB0 aGVyZSBhbnkgb2J2aW91cyBwaXRmYWxscyBvciBjYXZlYXRzIHRoYXQgaGF2ZSBub3QgYmVlbg0K PiBjb25zaWRlcmVkPyANCg0KTm90ZSB0aGF0IEtpcmlsbCBhdHRlbXB0ZWQgc29tZXRoaW5nIGxp a2UgdGhpcyBpbiAyMDEyIC0gc2VlDQpodHRwczovL3d3dy5zcGluaWNzLm5ldC9saXN0cy9saW51 eC1tbS9tc2c0MDU3NS5odG1sDQoNCi4uLg0KPiArKysgYi9hcmNoL3g4Ni9saWIvY2xlYXJfZ2ln YW50aWNfcGFnZS5jDQo+IEBAIC0wLDAgKzEsMjkgQEANCj4gKyNpbmNsdWRlIDxhc20vcGFnZS5o Pg0KPiArDQo+ICsjaW5jbHVkZSA8bGludXgva2VybmVsLmg+DQo+ICsjaW5jbHVkZSA8bGludXgv bW0uaD4NCj4gKyNpbmNsdWRlIDxsaW51eC9zY2hlZC5oPg0KPiArDQo+ICsjaWYgZGVmaW5lZChD T05GSUdfVFJBTlNQQVJFTlRfSFVHRVBBR0UpIHx8DQo+IGRlZmluZWQoQ09ORklHX0hVR0VUTEJG UykNCj4gKyNkZWZpbmUgUEFHRVNfQkVUV0VFTl9SRVNDSEVEIDY0DQo+ICt2b2lkIGNsZWFyX2dp Z2FudGljX3BhZ2Uoc3RydWN0IHBhZ2UgKnBhZ2UsDQo+ICsJCQkJdW5zaWduZWQgbG9uZyBhZGRy LA0KDQpUaGUgcHJldmlvdXMgYXR0ZW1wdCB1c2VkIGNhY2hlYWJsZSBzdG9yZXMgaW4gdGhlIHBh Z2UgY29udGFpbmluZw0KYWRkciB0byBwcmV2ZW50IGFuIGluZXZpdGFibGUgY2FjaGUgbWlzcyBh ZnRlciB0aGUgY2xlYXJpbmcgY29tcGxldGVzLg0KVGhpcyBmdW5jdGlvbiBpcyBub3QgdXNpbmcg YWRkciBhdCBhbGwuDQoNCj4gKwkJCQl1bnNpZ25lZCBpbnQgcGFnZXNfcGVyX2h1Z2VfcGFnZSkN Cj4gK3sNCj4gKwlpbnQgaTsNCj4gKwl2b2lkICpkZXN0ID0gcGFnZV90b192aXJ0KHBhZ2UpOw0K PiArCWludCByZXNjaGVkX2NvdW50ID0gMDsNCj4gKw0KPiArCUJVR19PTihwYWdlc19wZXJfaHVn ZV9wYWdlICUgUEFHRVNfQkVUV0VFTl9SRVNDSEVEICE9IDApOw0KPiArCUJVR19PTighZGVzdCk7 DQoNCkFyZSB0aG9zZSByZWFsbHkgcG9zc2libGUgY29uZGl0aW9ucz8gIElzIHRoZXJlIGEgc2Fm ZXIgZmFsbGJhY2sNCnRoYW4gY3Jhc2hpbmcgdGhlIHdob2xlIGtlcm5lbD8NCg0KPiArDQo+ICsJ Zm9yIChpID0gMDsgaSA8IHBhZ2VzX3Blcl9odWdlX3BhZ2U7IGkgKz0NCj4gUEFHRVNfQkVUV0VF Tl9SRVNDSEVEKSB7DQo+ICsJCV9fY2xlYXJfcGFnZV9udChkZXN0ICsgKGkgKiBQQUdFX1NJWkUp LA0KPiArCQkJCVBBR0VTX0JFVFdFRU5fUkVTQ0hFRCAqIFBBR0VfU0laRSk7DQo+ICsJCXJlc2No ZWRfY291bnQgKz0gY29uZF9yZXNjaGVkKCk7DQo+ICsJfQ0KPiArCS8qIF9fY2xlYXJfcGFnZV9u dCByZXF1cmlyZXMgYW5kIGBzZmVuY2VgIGJhcnJpZXIuICovDQoNCnJlcXVpcmVzIGFuDQoNCi4u Lg0KPiBkaWZmIC0tZ2l0IGEvYXJjaC94ODYvbGliL2NsZWFyX3BhZ2VfNjQuUw0KLi4uDQo+ICsv Kg0KPiArICogWmVybyBtZW1vcnkgdXNpbmcgbm9uIHRlbXBvcmFsIHN0b3JlcywgYnlwYXNzaW5n IHRoZSBjYWNoZS4NCj4gKyAqIFJlcXVpcmVzIGFuIGBzZmVuY2VgICh3bWIoKSkgYWZ0ZXJ3YXJk cy4NCj4gKyAqICVyZGkgLSBkZXN0aW5hdGlvbi4NCj4gKyAqICVyc2kgLSBwYWdlIHNpemUuIE11 c3QgYmUgNjQgYml0IGFsaWduZWQuDQo+ICsqLw0KPiArRU5UUlkoX19jbGVhcl9wYWdlX250KQ0K PiArCWxlYXEJKCVyZGksJXJzaSksICVyZHgNCj4gKwl4b3JsCSVlYXgsICVlYXgNCj4gKwkucDJh bGlnbiA0LCwxMA0KPiArCS5wMmFsaWduIDMNCj4gKy5MMjoNCj4gKwltb3ZudGkJJXJheCwgKCVy ZGkpDQo+ICsJYWRkcQkkOCwgJXJkaQ0KDQpBbHNvIGNvbnNpZGVyIHVzaW5nIHRoZSBBVlggdm1v dm50ZHEgaW5zdHJ1Y3Rpb24gKGlmIGF2YWlsYWJsZSksIHRoZQ0KbW9zdCByZWNlbnQgb2Ygd2hp Y2ggZG9lcyA2NC1ieXRlIChjYWNoZSBsaW5lKSBzaXplZCB0cmFuc2ZlcnMgdG8NCnptbSByZWdp c3RlcnMuIFRoZXJlJ3MgYSBoZWZ0eSBjb250ZXh0IHN3aXRjaGluZyBvdmVyaGVhZCAoZS5nLiwN CjMwNCBjbG9ja3MpLCBidXQgaXQgbWlnaHQgYmUgd29ydGh3aGlsZSBmb3IgMSBHaUIgKHdoaWNo DQppcyAxNiw3NzcsMjE2IGNhY2hlIGxpbmVzKS4NCg0KZ2xpYmMgbWVtY3B5KCkgbWFrZXMgdGhh dCBjaG9pY2UgZm9yIHRyYW5zZmVycyA+IDc1JSBvZiB0aGUgTDMgY2FjaGUNCnNpemUgZGl2aWRl ZCBieSB0aGUgbnVtYmVyIG9mIGNvcmVzLiAgKGxhc3QgSSB0cmllZCwgaXQgd2FzIHN0aWxsDQpz ZWxlY3RpbmcgInJlcCBzdG9zYiIgZm9yIGxhcmdlIG1lbXNldCgpcywgYWx0aG91Z2ggaXQgaGFz IGFuDQpBVlgtNTEyIGZ1bmN0aW9uIGF2YWlsYWJsZSkNCg0KRXZlbiB3aXRoIHRoYXQsIG9uZSBD UFUgY29yZSB3b24ndCBzYXR1cmF0ZSB0aGUgbWVtb3J5IGJ1czsgbXVsdGlwbGUNCkNQVSBjb3Jl cyAocHJlZmVyYWJseSBvbiB0aGUgc2FtZSBOVU1BIG5vZGUgYXMgdGhlIG1lbW9yeSkgbmVlZCB0 bw0Kc2hhcmUgdGhlIHdvcmsuDQoNCi0tLQ0KUm9iZXJ0IEVsbGlvdHQsIEhQRSBQZXJzaXN0ZW50 IE1lbW9yeQ0KDQoNCg0K