From mboxrd@z Thu Jan 1 00:00:00 1970 From: Samuel Pitoiset Subject: Re: [PATCH] nouveau: fix nv40_perfctr_next() cleanup regression Date: Wed, 16 Mar 2016 20:34:57 +0100 Message-ID: <56E9B561.3060401@gmail.com> References: <1457965458-3319933-1-git-send-email-arnd@arndb.de> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; Format="flowed" Content-Transfer-Encoding: base64 Return-path: Received: from mail-wm0-x236.google.com (mail-wm0-x236.google.com [IPv6:2a00:1450:400c:c09::236]) by gabe.freedesktop.org (Postfix) with ESMTPS id 1936C6E2C3 for ; Wed, 16 Mar 2016 19:35:02 +0000 (UTC) Received: by mail-wm0-x236.google.com with SMTP id p65so87374171wmp.0 for ; Wed, 16 Mar 2016 12:35:02 -0700 (PDT) In-Reply-To: <1457965458-3319933-1-git-send-email-arnd@arndb.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Arnd Bergmann , David Airlie Cc: Ben Skeggs , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org List-Id: dri-devel@lists.freedesktop.org UmV2aWV3ZWQtYnk6IFNhbXVlbCBQaXRvaXNldCA8c2FtdWVsLnBpdG9pc2V0QGdtYWlsLmNvbT4K Ck9uIDAzLzE0LzIwMTYgMDM6MjQgUE0sIEFybmQgQmVyZ21hbm4gd3JvdGU6Cj4gZ2NjLTYgd2Fy bnMgYWJvdXQgY29kZSBpbiB0aGUgbm91dmVhdSBkcml2ZXIgdGhhdCBpcyBvYnZpb3VzbHkgc2ls bHk6Cj4KPiBkcml2ZXJzL2dwdS9kcm0vbm91dmVhdS9udmttL2VuZ2luZS9wbS9udjQwLmM6IElu IGZ1bmN0aW9uICdudjQwX3BlcmZjdHJfbmV4dCc6Cj4gZHJpdmVycy9ncHUvZHJtL25vdXZlYXUv bnZrbS9lbmdpbmUvcG0vbnY0MC5jOjYyOjE5OiB3YXJuaW5nOiBzZWxmLWNvbXBhcmlzb24gYWx3 YXlzIGV2YWx1YXRzIHRvIGZhbHNlIFstV3RhdXRvbG9naWNhbC1jb21wYXJlXQo+ICAgIGlmIChw bS0+c2VxdWVuY2UgIT0gcG0tPnNlcXVlbmNlKSB7Cj4KPiBUaGUgYmVoYXZpb3Igd2FzIGFjY2lk ZW50YWxseSBpbnRyb2R1Y2VkIGluIGEgcGF0Y2ggZGVzY3JpYmVkIGFzICJUaGlzIGlzCj4gcHVy ZWx5IHByZXBhcmF0aW9uIGZvciB1cGNvbWluZyBjb21taXRzLCB0aGVyZSBzaG91bGQgYmUgbm8g Y29kZSBjaGFuZ2VzIGhlcmUuIi4KPiBBcyBmYXIgYXMgSSBjYW4gdGVsbCwgdGhhdCB3YXMgdHJ1 ZSBmb3IgdGhlIHJlc3Qgb2YgdGhhdCBwYXRjaCBleGNlcHQgZm9yCj4gdGhpcyBvbmUgZnVuY3Rp b24sIHdoaWNoIGhhcyBiZWVuIGNoYW5nZWQgdG8gYSBOT1AuCj4KPiBUaGlzIHBhdGNoIHJlc3Rv cmVzIHRoZSBvcmlnaW5hbCBiZWhhdmlvci4KPgo+IFNpZ25lZC1vZmYtYnk6IEFybmQgQmVyZ21h bm4gPGFybmRAYXJuZGIuZGU+Cj4gRml4ZXM6IDhjMWFlYWExMzk1NCAoImRybS9ub3V2ZWF1L3Bt OiBjb3NtZXRpYyBjaGFuZ2VzIikKPiAtLS0KPiAgIGRyaXZlcnMvZ3B1L2RybS9ub3V2ZWF1L252 a20vZW5naW5lL3BtL252NDAuYyB8IDYgKysrKy0tCj4gICAxIGZpbGUgY2hhbmdlZCwgNCBpbnNl cnRpb25zKCspLCAyIGRlbGV0aW9ucygtKQo+Cj4gZGlmZiAtLWdpdCBhL2RyaXZlcnMvZ3B1L2Ry bS9ub3V2ZWF1L252a20vZW5naW5lL3BtL252NDAuYyBiL2RyaXZlcnMvZ3B1L2RybS9ub3V2ZWF1 L252a20vZW5naW5lL3BtL252NDAuYwo+IGluZGV4IDRiZWY3MmE5ZDEwNi4uM2ZkYTU5NDcwMGUw IDEwMDY0NAo+IC0tLSBhL2RyaXZlcnMvZ3B1L2RybS9ub3V2ZWF1L252a20vZW5naW5lL3BtL252 NDAuYwo+ICsrKyBiL2RyaXZlcnMvZ3B1L2RybS9ub3V2ZWF1L252a20vZW5naW5lL3BtL252NDAu Ywo+IEBAIC01OSw5ICs1OSwxMSBAQCBzdGF0aWMgdm9pZAo+ICAgbnY0MF9wZXJmY3RyX25leHQo c3RydWN0IG52a21fcG0gKnBtLCBzdHJ1Y3QgbnZrbV9wZXJmZG9tICpkb20pCj4gICB7Cj4gICAJ c3RydWN0IG52a21fZGV2aWNlICpkZXZpY2UgPSBwbS0+ZW5naW5lLnN1YmRldi5kZXZpY2U7Cj4g LQlpZiAocG0tPnNlcXVlbmNlICE9IHBtLT5zZXF1ZW5jZSkgewo+ICsJc3RydWN0IG52NDBfcG0g Km52NDBwbSA9IGNvbnRhaW5lcl9vZihwbSwgc3RydWN0IG52NDBfcG0sIGJhc2UpOwo+ICsKPiAr CWlmIChudjQwcG0tPnNlcXVlbmNlICE9IHBtLT5zZXF1ZW5jZSkgewo+ICAgCQludmttX3dyMzIo ZGV2aWNlLCAweDQwMDA4NCwgMHgwMDAwMDAyMCk7Cj4gLQkJcG0tPnNlcXVlbmNlID0gcG0tPnNl cXVlbmNlOwo+ICsJCW52NDBwbS0+c2VxdWVuY2UgPSBwbS0+c2VxdWVuY2U7Cj4gICAJfQo+ICAg fQo+Cj4KX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KZHJp LWRldmVsIG1haWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBz Oi8vbGlzdHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vZHJpLWRldmVsCg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934465AbcCPTfF (ORCPT ); Wed, 16 Mar 2016 15:35:05 -0400 Received: from mail-wm0-f45.google.com ([74.125.82.45]:36987 "EHLO mail-wm0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755335AbcCPTfB (ORCPT ); Wed, 16 Mar 2016 15:35:01 -0400 Subject: Re: [PATCH] nouveau: fix nv40_perfctr_next() cleanup regression To: Arnd Bergmann , David Airlie References: <1457965458-3319933-1-git-send-email-arnd@arndb.de> Cc: Ben Skeggs , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org From: Samuel Pitoiset Message-ID: <56E9B561.3060401@gmail.com> Date: Wed, 16 Mar 2016 20:34:57 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <1457965458-3319933-1-git-send-email-arnd@arndb.de> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Reviewed-by: Samuel Pitoiset On 03/14/2016 03:24 PM, Arnd Bergmann wrote: > gcc-6 warns about code in the nouveau driver that is obviously silly: > > drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c: In function 'nv40_perfctr_next': > drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c:62:19: warning: self-comparison always evaluats to false [-Wtautological-compare] > if (pm->sequence != pm->sequence) { > > The behavior was accidentally introduced in a patch described as "This is > purely preparation for upcoming commits, there should be no code changes here.". > As far as I can tell, that was true for the rest of that patch except for > this one function, which has been changed to a NOP. > > This patch restores the original behavior. > > Signed-off-by: Arnd Bergmann > Fixes: 8c1aeaa13954 ("drm/nouveau/pm: cosmetic changes") > --- > drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c b/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c > index 4bef72a9d106..3fda594700e0 100644 > --- a/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c > +++ b/drivers/gpu/drm/nouveau/nvkm/engine/pm/nv40.c > @@ -59,9 +59,11 @@ static void > nv40_perfctr_next(struct nvkm_pm *pm, struct nvkm_perfdom *dom) > { > struct nvkm_device *device = pm->engine.subdev.device; > - if (pm->sequence != pm->sequence) { > + struct nv40_pm *nv40pm = container_of(pm, struct nv40_pm, base); > + > + if (nv40pm->sequence != pm->sequence) { > nvkm_wr32(device, 0x400084, 0x00000020); > - pm->sequence = pm->sequence; > + nv40pm->sequence = pm->sequence; > } > } > >