From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751699AbdF1Pk6 (ORCPT ); Wed, 28 Jun 2017 11:40:58 -0400 Received: from mail-sn1nam02on0084.outbound.protection.outlook.com ([104.47.36.84]:47804 "EHLO NAM02-SN1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751566AbdF1Pkw (ORCPT ); Wed, 28 Jun 2017 11:40:52 -0400 From: "Deucher, Alexander" To: "'Gustavo A. R. Silva'" , "Koenig, Christian" , David Airlie CC: "amd-gfx@lists.freedesktop.org" , "dri-devel@lists.freedesktop.org" , "linux-kernel@vger.kernel.org" Subject: RE: [gpu-drm-radeon] question about potential dead code in vce_v2_0_enable_mgcg() Thread-Topic: [gpu-drm-radeon] question about potential dead code in vce_v2_0_enable_mgcg() Thread-Index: AQHS8Bn8SxoT2DaM9UC/vW5M3X/elqI6aUxg Date: Wed, 28 Jun 2017 15:40:49 +0000 Message-ID: References: <20170628092229.Horde.Hsk18WJyYojTJE5OKzhVd3d@gator4166.hostgator.com> In-Reply-To: <20170628092229.Horde.Hsk18WJyYojTJE5OKzhVd3d@gator4166.hostgator.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: embeddedor.com; dkim=none (message not signed) header.d=none;embeddedor.com; dmarc=none action=none header.from=amd.com; x-originating-ip: [165.204.55.251] x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;BN6PR12MB1300;20:1a5anVCQhF38+ZQseCAERKcvNhL0Eued8BKxtKNPI6Ax/lN5DfQH1Zn1D7AkqC+sV1exCPTUky7cqXKP7aD859bD/uEX+v8aMRs7RRFiEOaJVjivdna0SSlVmRvYZmMPL5ENUvIgPepIqu2BPrLbZVTvZdNS2tNIkwW5TJR6Jyi6I1/wAl9TEyKm0/Ue0R8nnAPzBkcNudLlR9+LQYnVf5uqdx3WAoue/PzodcCkE2BetseWjpO8hl6PRm9wHub0 x-forefront-antispam-report: SFV:SKI;SCL:-1SFV:NSPM;SFS:(10009020)(6009001)(39450400003)(39840400002)(39850400002)(39860400002)(39410400002)(39400400002)(53754006)(13464003)(377454003)(3846002)(6116002)(54356999)(54906002)(99286003)(55016002)(9686003)(6436002)(3660700001)(33656002)(6506006)(2906002)(25786009)(4326008)(3280700002)(2900100001)(53546010)(7736002)(81166006)(8676002)(189998001)(66066001)(8936002)(230783001)(7696004)(5660300001)(478600001)(72206003)(53936002)(2950100002)(14454004)(6246003)(229853002)(38730400002)(86362001)(305945005)(76176999)(74316002)(77096006)(50986999)(15760500002);DIR:OUT;SFP:1101;SCL:1;SRVR:BN6PR12MB1300;H:BN6PR12MB1652.namprd12.prod.outlook.com;FPR:;SPF:None;MLV:sfv;LANG:en; x-ms-office365-filtering-correlation-id: ee8099c3-5d34-4765-ec89-08d4be3c0d2e x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: UriScan:;BCL:0;PCL:0;RULEID:(300000500095)(300135000095)(300000501095)(300135300095)(22001)(300000502095)(300135100095)(2017030254075)(300000503095)(300135400095)(48565401081)(201703131423075)(201703031133081)(300000504095)(300135200095)(300000505095)(300135600095)(300000506095)(300135500095);SRVR:BN6PR12MB1300; x-ms-traffictypediagnostic: BN6PR12MB1300: x-microsoft-antispam-prvs: x-exchange-antispam-report-test: UriScan:(236129657087228)(9452136761055)(217544274631240); x-exchange-antispam-report-cfa-test: BCL:0;PCL:0;RULEID:(100000700101)(100105000095)(100000701101)(100105300095)(100000702101)(100105100095)(6040450)(601004)(2401047)(8121501046)(5005006)(100000703101)(100105400095)(10201501046)(93006095)(93001095)(3002001)(6055026)(6041248)(20161123555025)(201703131423075)(201702281528075)(201703061421075)(201703061406153)(20161123562025)(20161123558100)(20161123560025)(20161123564025)(6072148)(100000704101)(100105200095)(100000705101)(100105500095);SRVR:BN6PR12MB1300;BCL:0;PCL:0;RULEID:(100000800101)(100110000095)(100000801101)(100110300095)(100000802101)(100110100095)(100000803101)(100110400095)(100000804101)(100110200095)(100000805101)(100110500095);SRVR:BN6PR12MB1300; x-forefront-prvs: 03524FBD26 spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-originalarrivaltime: 28 Jun 2017 15:40:49.3483 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN6PR12MB1300 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id v5SFf4tL006638 > -----Original Message----- > From: Gustavo A. R. Silva [mailto:garsilva@embeddedor.com] > Sent: Wednesday, June 28, 2017 10:22 AM > To: Deucher, Alexander; Koenig, Christian; David Airlie > Cc: amd-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org; linux- > kernel@vger.kernel.org > Subject: [gpu-drm-radeon] question about potential dead code in > vce_v2_0_enable_mgcg() > > > Hello everybody, > > While looking into Coverity ID 1198635 I ran into the following piece > of code at drivers/gpu/drm/radeon/vce_v2_0.c:107: > > 107void vce_v2_0_enable_mgcg(struct radeon_device *rdev, bool enable) > 108{ > 109 bool sw_cg = false; > 110 > 111 if (enable && (rdev->cg_flags & > RADEON_CG_SUPPORT_VCE_MGCG)) { > 112 if (sw_cg) > 113 vce_v2_0_set_sw_cg(rdev, true); > 114 else > 115 vce_v2_0_set_dyn_cg(rdev, true); > 116 } else { > 117 vce_v2_0_disable_cg(rdev); > 118 > 119 if (sw_cg) > 120 vce_v2_0_set_sw_cg(rdev, false); > 121 else > 122 vce_v2_0_set_dyn_cg(rdev, false); > 123 } > 124} > > The issue here is that local variable sw_cg is never updated again > after its initialization; which cause some code to be logically dead. > > My question here is if such variable is there for testing purposes or > if it is a sort of an old code leftover that should be removed? > > In any case I can send a patch to add a comment or remove the dead code. > > I'd really appreciate any comments on this. I wanted to leave the code in for debugging if we ran into problems with dynamic clockgating. Alex From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Deucher, Alexander" Subject: RE: [gpu-drm-radeon] question about potential dead code in vce_v2_0_enable_mgcg() Date: Wed, 28 Jun 2017 15:40:49 +0000 Message-ID: References: <20170628092229.Horde.Hsk18WJyYojTJE5OKzhVd3d@gator4166.hostgator.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20170628092229.Horde.Hsk18WJyYojTJE5OKzhVd3d-fU+oOHjIBR1LoJgMfuPDHBfZZeVsHd8q@public.gmane.org> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: amd-gfx-bounces-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Sender: "amd-gfx" To: "'Gustavo A. R. Silva'" , "Koenig, Christian" , David Airlie Cc: "dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org" , "amd-gfx-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: dri-devel@lists.freedesktop.org PiAtLS0tLU9yaWdpbmFsIE1lc3NhZ2UtLS0tLQ0KPiBGcm9tOiBHdXN0YXZvIEEuIFIuIFNpbHZh IFttYWlsdG86Z2Fyc2lsdmFAZW1iZWRkZWRvci5jb21dDQo+IFNlbnQ6IFdlZG5lc2RheSwgSnVu ZSAyOCwgMjAxNyAxMDoyMiBBTQ0KPiBUbzogRGV1Y2hlciwgQWxleGFuZGVyOyBLb2VuaWcsIENo cmlzdGlhbjsgRGF2aWQgQWlybGllDQo+IENjOiBhbWQtZ2Z4QGxpc3RzLmZyZWVkZXNrdG9wLm9y ZzsgZHJpLWRldmVsQGxpc3RzLmZyZWVkZXNrdG9wLm9yZzsgbGludXgtDQo+IGtlcm5lbEB2Z2Vy Lmtlcm5lbC5vcmcNCj4gU3ViamVjdDogW2dwdS1kcm0tcmFkZW9uXSBxdWVzdGlvbiBhYm91dCBw b3RlbnRpYWwgZGVhZCBjb2RlIGluDQo+IHZjZV92Ml8wX2VuYWJsZV9tZ2NnKCkNCj4gDQo+IA0K PiBIZWxsbyBldmVyeWJvZHksDQo+IA0KPiBXaGlsZSBsb29raW5nIGludG8gQ292ZXJpdHkgSUQg MTE5ODYzNSBJIHJhbiBpbnRvIHRoZSBmb2xsb3dpbmcgcGllY2UNCj4gb2YgY29kZSBhdCBkcml2 ZXJzL2dwdS9kcm0vcmFkZW9uL3ZjZV92Ml8wLmM6MTA3Og0KPiANCj4gMTA3dm9pZCB2Y2VfdjJf MF9lbmFibGVfbWdjZyhzdHJ1Y3QgcmFkZW9uX2RldmljZSAqcmRldiwgYm9vbCBlbmFibGUpDQo+ IDEwOHsNCj4gMTA5ICAgICAgICBib29sIHN3X2NnID0gZmFsc2U7DQo+IDExMA0KPiAxMTEgICAg ICAgIGlmIChlbmFibGUgJiYgKHJkZXYtPmNnX2ZsYWdzICYNCj4gUkFERU9OX0NHX1NVUFBPUlRf VkNFX01HQ0cpKSB7DQo+IDExMiAgICAgICAgICAgICAgICBpZiAoc3dfY2cpDQo+IDExMyAgICAg ICAgICAgICAgICAgICAgICAgIHZjZV92Ml8wX3NldF9zd19jZyhyZGV2LCB0cnVlKTsNCj4gMTE0 ICAgICAgICAgICAgICAgIGVsc2UNCj4gMTE1ICAgICAgICAgICAgICAgICAgICAgICAgdmNlX3Yy XzBfc2V0X2R5bl9jZyhyZGV2LCB0cnVlKTsNCj4gMTE2ICAgICAgICB9IGVsc2Ugew0KPiAxMTcg ICAgICAgICAgICAgICAgdmNlX3YyXzBfZGlzYWJsZV9jZyhyZGV2KTsNCj4gMTE4DQo+IDExOSAg ICAgICAgICAgICAgICBpZiAoc3dfY2cpDQo+IDEyMCAgICAgICAgICAgICAgICAgICAgICAgIHZj ZV92Ml8wX3NldF9zd19jZyhyZGV2LCBmYWxzZSk7DQo+IDEyMSAgICAgICAgICAgICAgICBlbHNl DQo+IDEyMiAgICAgICAgICAgICAgICAgICAgICAgIHZjZV92Ml8wX3NldF9keW5fY2cocmRldiwg ZmFsc2UpOw0KPiAxMjMgICAgICAgIH0NCj4gMTI0fQ0KPiANCj4gVGhlIGlzc3VlIGhlcmUgaXMg dGhhdCBsb2NhbCB2YXJpYWJsZSBzd19jZyBpcyBuZXZlciB1cGRhdGVkIGFnYWluDQo+IGFmdGVy IGl0cyBpbml0aWFsaXphdGlvbjsgd2hpY2ggY2F1c2Ugc29tZSBjb2RlIHRvIGJlIGxvZ2ljYWxs eSBkZWFkLg0KPiANCj4gTXkgcXVlc3Rpb24gaGVyZSBpcyBpZiBzdWNoIHZhcmlhYmxlIGlzIHRo ZXJlIGZvciB0ZXN0aW5nIHB1cnBvc2VzIG9yDQo+IGlmIGl0IGlzIGEgc29ydCBvZiBhbiBvbGQg Y29kZSBsZWZ0b3ZlciB0aGF0IHNob3VsZCBiZSByZW1vdmVkPw0KPiANCj4gSW4gYW55IGNhc2Ug SSBjYW4gc2VuZCBhIHBhdGNoIHRvIGFkZCBhIGNvbW1lbnQgb3IgcmVtb3ZlIHRoZSBkZWFkIGNv ZGUuDQo+IA0KPiBJJ2QgcmVhbGx5IGFwcHJlY2lhdGUgYW55IGNvbW1lbnRzIG9uIHRoaXMuDQoN Ckkgd2FudGVkIHRvIGxlYXZlIHRoZSBjb2RlIGluIGZvciBkZWJ1Z2dpbmcgaWYgd2UgcmFuIGlu dG8gcHJvYmxlbXMgd2l0aCBkeW5hbWljIGNsb2NrZ2F0aW5nLg0KDQpBbGV4DQoNCl9fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmFtZC1nZnggbWFpbGluZyBs aXN0CmFtZC1nZnhAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlzdHMuZnJlZWRlc2t0 b3Aub3JnL21haWxtYW4vbGlzdGluZm8vYW1kLWdmeAo=