Received: by 2002:a05:6a10:8c0a:0:0:0:0 with SMTP id go10csp339481pxb; Thu, 25 Feb 2021 04:07:32 -0800 (PST) X-Google-Smtp-Source: ABdhPJznNopRhNWpDwY8hukQplmIT6j7uzO0I/+vH0erFwHCkDGdbc71xLo5ScnzdGvjKufhV8fb X-Received: by 2002:a17:906:4c51:: with SMTP id d17mr2284219ejw.533.1614254852608; Thu, 25 Feb 2021 04:07:32 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1614254852; cv=none; d=google.com; s=arc-20160816; b=DhDZJvA/i1KiI/4/7NF7qc0T1x9rein8r3uo2fM2owhGOq7CeGvRQ8pKoQ7rH7wLqw 8M4KUwje85SMRSGs1NMFAAtjLEWDzbnTAwZEJ6EjH3i3FNW91N7BiV0C8B8F3Na7EfJX mYWcVi2Qpdft1KIi+aVXiLWdUxUbjkDRcgGdP6uQ7YDBKe962r2s1gcC68kM5jbQs8We dHKo3cipmmDguH2WRmeCKjB/51swu0YWDzeVmGSjGDkCRSOrX4xYrEXiJBZztXhVG73M jd8ib2McX3EIacVBEpC9R1Kyl4MoHNwG6h4I7bz9jc9LXnAUyEzO2aWgvIJ6R/C0WGQI bQdw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:mime-version:content-transfer-encoding :content-language:accept-language:in-reply-to:references:message-id :date:thread-index:thread-topic:subject:cc:to:from; bh=QetWo2+V8CWYVTdWTSKISrJcTi/f09sAIWyVgYZnLmU=; b=KpCDHQiIJQVItriaJW1o+BWy01CxzZcdg/D073iZr7gCHUGUKtfUDYu0Mw2BCmg4ka 9mcN4s/AeiMeuhn/8G99WCPqaPkiCB1x1hu8m/5uBTecWRShehSYGvJy4N2P9IcDtCX9 pjM76rMGb2HqOMkFtbwtSDasF147mIwInfxkkb68knv3OP6YqESbnTGhnyJLh9/iX0ZN V1BFHgLGH80usVRcC9CH/BmsqbFB/9qJU2V+NCrWwtQ2G4FZgAkdMqfs/VrGolNmk6dS l/04eOhFqu1Hm63qFbiOEUlgkLvf/vEzGILefYhDhNjoHWqiNgNYskC703A9mJF9FmKn RFzQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id e23si3127984edu.203.2021.02.25.04.07.10; Thu, 25 Feb 2021 04:07:32 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233375AbhBYMET (ORCPT + 99 others); Thu, 25 Feb 2021 07:04:19 -0500 Received: from szxga01-in.huawei.com ([45.249.212.187]:2588 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229769AbhBYMEK (ORCPT ); Thu, 25 Feb 2021 07:04:10 -0500 Received: from DGGEMM404-HUB.china.huawei.com (unknown [172.30.72.55]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4DmWZh1bwBzW7yC; Thu, 25 Feb 2021 20:00:44 +0800 (CST) Received: from dggemm751-chm.china.huawei.com (10.1.198.57) by DGGEMM404-HUB.china.huawei.com (10.3.20.212) with Microsoft SMTP Server (TLS) id 14.3.498.0; Thu, 25 Feb 2021 20:03:19 +0800 Received: from dggeme758-chm.china.huawei.com (10.3.19.104) by dggemm751-chm.china.huawei.com (10.1.198.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2106.2; Thu, 25 Feb 2021 20:03:19 +0800 Received: from dggeme758-chm.china.huawei.com ([10.6.80.69]) by dggeme758-chm.china.huawei.com ([10.6.80.69]) with mapi id 15.01.2106.006; Thu, 25 Feb 2021 20:03:19 +0800 From: "Wanghongzhe (Hongzhe, EulerOS)" To: Andy Lutomirski CC: "keescook@chromium.org" , "andrii@kernel.org" , "ast@kernel.org" , "bpf@vger.kernel.org" , "daniel@iogearbox.net" , "john.fastabend@gmail.com" , "kafai@fb.com" , "kpsingh@kernel.org" , "linux-kernel@vger.kernel.org" , "netdev@vger.kernel.org" , "songliubraving@fb.com" , "wad@chromium.org" , "yhs@fb.com" , tongxiaomeng Subject: RE: [PATCH v3] seccomp: Improve performace by optimizing rmb() Thread-Topic: [PATCH v3] seccomp: Improve performace by optimizing rmb() Thread-Index: AQHXCoNzuX/zLaYh0E+0oBVdFxPnyKpm9kQAgAHQ2PA= Date: Thu, 25 Feb 2021 12:03:19 +0000 Message-ID: References: <1614156585-18842-1-git-send-email-wanghongzhe@huawei.com> <638D44BA-0ACA-4041-8213-217233656A70@amacapital.net> In-Reply-To: <638D44BA-0ACA-4041-8213-217233656A70@amacapital.net> Accept-Language: en-US Content-Language: zh-CN X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.174.176.70] Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 MIME-Version: 1.0 X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org PiA+IE9uIEZlYiAyNCwgMjAyMSwgYXQgMTI6MDMgQU0sIHdhbmdob25nemhlIDx3YW5naG9uZ3po ZUBodWF3ZWkuY29tPg0KPiB3cm90ZToNCj4gPg0KPiA+IO+7v0FzIEtlZXMgaGF2ZWQgYWNjZXB0 ZWQgdGhlIHYyIHBhdGNoIGF0IGEzODFiNzBhMSB3aGljaCBqdXN0IHJlcGxhY2VkDQo+ID4gcm1i KCkgd2l0aCBzbXBfcm1iKCksIHRoaXMgcGF0Y2ggd2lsbCBiYXNlIG9uIHRoYXQgYW5kIGp1c3Qg YWRqdXN0IHRoZQ0KPiA+IHNtcF9ybWIoKSB0byB0aGUgY29ycmVjdCBwb3NpdGlvbi4NCj4gPg0K PiA+IEFzIHRoZSBvcmlnaW5hbCBjb21tZW50IHNob3duIChhbmQgaW5kZWVkIGl0IHNob3VsZCBi ZSk6DQo+ID4gICAvKg0KPiA+ICAgICogTWFrZSBzdXJlIHRoYXQgYW55IGNoYW5nZXMgdG8gbW9k ZSBmcm9tIGFub3RoZXIgdGhyZWFkIGhhdmUNCj4gPiAgICAqIGJlZW4gc2VlbiBhZnRlciBTWVND QUxMX1dPUktfU0VDQ09NUCB3YXMgc2Vlbi4NCj4gPiAgICAqLw0KPiA+IHRoZSBzbXBfcm1iKCkg c2hvdWxkIGJlIHB1dCBiZXR3ZWVuIHJlYWRpbmcgU1lTQ0FMTF9XT1JLX1NFQ0NPTVANCj4gYW5k DQo+ID4gcmVhZGluZyBzZWNjb21wLm1vZGUgdG8gbWFrZSBzdXJlIHRoYXQgYW55IGNoYW5nZXMg dG8gbW9kZSBmcm9tDQo+ID4gYW5vdGhlciB0aHJlYWQgaGF2ZSBiZWVuIHNlZW4gYWZ0ZXIgU1lT Q0FMTF9XT1JLX1NFQ0NPTVAgd2FzIHNlZW4sDQo+IGZvcg0KPiA+IFRTWU5DIHNpdHVhdGlvbi4g SG93ZXZlciwgaXQgaXMgbWlzcGxhY2VkIGJldHdlZW4gcmVhZGluZyBzZWNjb21wLm1vZGUNCj4g PiBhbmQgc2VjY29tcC0+ZmlsdGVyLiBUaGlzIGlzc3VlIHNlZW1zIHRvIGJlIG1pc2ludHJvZHVj ZWQgYXQNCj4gPiAxM2FhNzJmMGZkMGE5Zjk4YTQxY2VmYjY2MjQ4NzI2OWUyZjFhZDY1IHdoaWNo IGFpbXMgdG8gcmVmYWN0b3IgdGhlDQo+ID4gZmlsdGVyIGNhbGxiYWNrIGFuZCB0aGUgQVBJLiBT byBsZXQncyBqdXN0IGFkanVzdCB0aGUNCj4gPiBzbXBfcm1iKCkgdG8gdGhlIGNvcnJlY3QgcG9z aXRpb24uDQo+ID4NCj4gPiBBIG5leHQgb3B0aW1pemF0aW9uIHBhdGNoIHdpbGwgYmUgcHJvdmlk ZWQgaWYgdGhpcyBhanVzdG1lbnQgaXMgYXBwcm9wcmlhdGUuDQo+IA0KPiBXb3VsZCBpdCBiZSBi ZXR0ZXIgdG8gbWFrZSB0aGUgc3lzY2FsbCB3b3JrIHJlYWQgYmUgc21wX2xvYWRfYWNxdWlyZSgp Pw0KPiANCj4gPg0KPiA+IHYyIC0+IHYzOg0KPiA+IC0gbW92ZSB0aGUgc21wX3JtYigpIHRvIHRo ZSBjb3JyZWN0IHBvc2l0aW9uDQo+ID4NCj4gPiB2MSAtPiB2MjoNCj4gPiAtIG9ubHkgcmVwbGFj ZSBybWIoKSB3aXRoIHNtcF9ybWIoKQ0KPiA+IC0gcHJvdmlkZSB0aGUgcGVyZm9ybWFuY2UgdGVz dCBudW1iZXINCj4gPg0KPiA+IFJGQyAtPiB2MToNCj4gPiAtIHJlcGxhY2Ugcm1iKCkgd2l0aCBz bXBfcm1iKCkNCj4gPiAtIG1vdmUgdGhlIHNtcF9ybWIoKSBsb2dpYyB0byB0aGUgbWlkZGxlIGJl dHdlZW4gVElGX1NFQ0NPTVAgYW5kIG1vZGUNCj4gPg0KPiA+IFNpZ25lZC1vZmYtYnk6IHdhbmdo b25nemhlIDx3YW5naG9uZ3poZUBodWF3ZWkuY29tPg0KPiA+IC0tLQ0KPiA+IGtlcm5lbC9zZWNj b21wLmMgfCAxNSArKysrKysrLS0tLS0tLS0NCj4gPiAxIGZpbGUgY2hhbmdlZCwgNyBpbnNlcnRp b25zKCspLCA4IGRlbGV0aW9ucygtKQ0KPiA+DQo+ID4gZGlmZiAtLWdpdCBhL2tlcm5lbC9zZWNj b21wLmMgYi9rZXJuZWwvc2VjY29tcC5jIGluZGV4DQo+ID4gMWQ2MGZjMmM5OTg3Li42NGIyMzZj YjhhN2YgMTAwNjQ0DQo+ID4gLS0tIGEva2VybmVsL3NlY2NvbXAuYw0KPiA+ICsrKyBiL2tlcm5l bC9zZWNjb21wLmMNCj4gPiBAQCAtMTE2MCwxMiArMTE2MCw2IEBAIHN0YXRpYyBpbnQgX19zZWNj b21wX2ZpbHRlcihpbnQgdGhpc19zeXNjYWxsLCBjb25zdA0KPiBzdHJ1Y3Qgc2VjY29tcF9kYXRh ICpzZCwNCj4gPiAgICBpbnQgZGF0YTsNCj4gPiAgICBzdHJ1Y3Qgc2VjY29tcF9kYXRhIHNkX2xv Y2FsOw0KPiA+DQo+ID4gLSAgICAvKg0KPiA+IC0gICAgICogTWFrZSBzdXJlIHRoYXQgYW55IGNo YW5nZXMgdG8gbW9kZSBmcm9tIGFub3RoZXIgdGhyZWFkIGhhdmUNCj4gPiAtICAgICAqIGJlZW4g c2VlbiBhZnRlciBTWVNDQUxMX1dPUktfU0VDQ09NUCB3YXMgc2Vlbi4NCj4gPiAtICAgICAqLw0K PiA+IC0gICAgc21wX3JtYigpOw0KPiA+IC0NCj4gPiAgICBpZiAoIXNkKSB7DQo+ID4gICAgICAg IHBvcHVsYXRlX3NlY2NvbXBfZGF0YSgmc2RfbG9jYWwpOw0KPiA+ICAgICAgICBzZCA9ICZzZF9s b2NhbDsNCj4gPiBAQCAtMTI5MSw3ICsxMjg1LDYgQEAgc3RhdGljIGludCBfX3NlY2NvbXBfZmls dGVyKGludCB0aGlzX3N5c2NhbGwsDQo+ID4gY29uc3Qgc3RydWN0IHNlY2NvbXBfZGF0YSAqc2Qs DQo+ID4NCj4gPiBpbnQgX19zZWN1cmVfY29tcHV0aW5nKGNvbnN0IHN0cnVjdCBzZWNjb21wX2Rh dGEgKnNkKSB7DQo+ID4gLSAgICBpbnQgbW9kZSA9IGN1cnJlbnQtPnNlY2NvbXAubW9kZTsNCj4g PiAgICBpbnQgdGhpc19zeXNjYWxsOw0KPiA+DQo+ID4gICAgaWYgKElTX0VOQUJMRUQoQ09ORklH X0NIRUNLUE9JTlRfUkVTVE9SRSkgJiYgQEAgLTEzMDEsNw0KPiArMTI5NCwxMyBAQA0KPiA+IGlu dCBfX3NlY3VyZV9jb21wdXRpbmcoY29uc3Qgc3RydWN0IHNlY2NvbXBfZGF0YSAqc2QpDQo+ID4g ICAgdGhpc19zeXNjYWxsID0gc2QgPyBzZC0+bnIgOg0KPiA+ICAgICAgICBzeXNjYWxsX2dldF9u cihjdXJyZW50LCBjdXJyZW50X3B0X3JlZ3MoKSk7DQo+ID4NCj4gPiAtICAgIHN3aXRjaCAobW9k ZSkgew0KPiA+ICsgICAgLyoNCj4gPiArICAgICAqIE1ha2Ugc3VyZSB0aGF0IGFueSBjaGFuZ2Vz IHRvIG1vZGUgZnJvbSBhbm90aGVyIHRocmVhZCBoYXZlDQo+ID4gKyAgICAgKiBiZWVuIHNlZW4g YWZ0ZXIgU1lTQ0FMTF9XT1JLX1NFQ0NPTVAgd2FzIHNlZW4uDQo+ID4gKyAgICAgKi8NCj4gPiAr ICAgIHNtcF9ybWIoKTsNCj4gPiArDQo+ID4gKyAgICBzd2l0Y2ggKGN1cnJlbnQtPnNlY2NvbXAu bW9kZSkgew0KPiA+ICAgIGNhc2UgU0VDQ09NUF9NT0RFX1NUUklDVDoNCj4gPiAgICAgICAgX19z ZWN1cmVfY29tcHV0aW5nX3N0cmljdCh0aGlzX3N5c2NhbGwpOyAgLyogbWF5IGNhbGwgZG9fZXhp dCAqLw0KPiA+ICAgICAgICByZXR1cm4gMDsNCj4gPiAtLQ0KPiA+IDIuMTkuMQ0KPiA+DQo+IFdv dWxkIGl0IGJlIGJldHRlciB0byBtYWtlIHRoZSBzeXNjYWxsIHdvcmsgcmVhZCBiZSBzbXBfbG9h ZF9hY3F1aXJlKCk/DQpNYXliZSB3ZSBjYW4gZG8gc29tZXRoaW5nIGxpa2UgdGhpcyAodW50ZXN0 ZWQpOiANCl9fc3lzY2FsbF9lbnRlcl9mcm9tX3VzZXJfd29yayhzdHJ1Y3QgcHRfcmVncyAqcmVn cywgbG9uZyBzeXNjYWxsKQ0Kew0KLSAgICAgIHVuc2lnbmVkIGxvbmcgd29yayA9IFJFQURfT05D RShjdXJyZW50X3RocmVhZF9pbmZvKCktPnN5c2NhbGxfd29yayk7DQorICAgICB1bnNpZ25lZCBs b25nIHdvcmsgPSBzbXBfbG9hZF9hY3F1aXJlICgmKGN1cnJlbnRfdGhyZWFkX2luZm8oKS0+c3lz Y2FsbF93b3JrKSk7DQoNCiAgICAgICBpZiAod29yayAmIFNZU0NBTExfV09SS19FTlRFUikNCiAg ICAgICAgICAgICAgc3lzY2FsbCA9IHN5c2NhbGxfdHJhY2VfZW50ZXIocmVncywgc3lzY2FsbCwg d29yayk7DQpIb3dldmVyLCB0aGlzIG1heSBpbnNlcnQgYSBtZW1vcnkgYmFycmllciBhbmQgc2xv dyBkb3duIGFsbCB3b3JrcyANCmJlaGluZCBpdCBpbiBTWVNDQUxMX1dPUktfRU5URVIsIG5vdCBq dXN0IHNlY2NvbXAsIHdoaWNoICBpcyBub3QgDQp3ZSB3YW50LiBBbmQgaW4gb3JkZXIgdG8gbWF0 Y2ggd2l0aCB0aGUgc21wX21iX19iZWZvcmVfYXRvbWljKCkgaW4gDQpzZWNjb21wX2Fzc2lnbl9t b2RlKCkgd2hpY2ggY2FsbGVkIGluIHNlY2NvbXBfc3luY190aHJlYWRzKCksIGl0IGlzIA0KYmV0 dGVyIHRvIHVzZSBzbXBfcm1iKCkgYmV0d2VlbiB0aGUgd29yayBhbmQgbW9kZSByZWFkOg0KICAg ICAgIHRhc2stPnNlY2NvbXAubW9kZSA9IHNlY2NvbXBfbW9kZTsNCiAgICAgICAvKg0KICAgICAg ICogTWFrZSBzdXJlIFNZU0NBTExfV09SS19TRUNDT01QIGNhbm5vdCBiZSBzZXQgYmVmb3JlIHRo ZSBtb2RlIChhbmQNCiAgICAgICAqIGZpbHRlcikgaXMgc2V0Lg0KICAgICAgICovDQoqICAgICAg c21wX21iX19iZWZvcmVfYXRvbWljKCk7DQogICAgICAgLyogQXNzdW1lIGRlZmF1bHQgc2VjY29t cCBwcm9jZXNzZXMgd2FudCBzcGVjIGZsYXcgbWl0aWdhdGlvbi4gKi8NCiAgICAgICBpZiAoKGZs YWdzICYgU0VDQ09NUF9GSUxURVJfRkxBR19TUEVDX0FMTE9XKSA9PSAwKQ0KICAgICAgICAgICAg ICBhcmNoX3NlY2NvbXBfc3BlY19taXRpZ2F0ZSh0YXNrKTsNCiAgICAgICBzZXRfdGFza19zeXNj YWxsX3dvcmsodGFzaywgU0VDQ09NUCk7DQoNCg==