From mboxrd@z Thu Jan 1 00:00:00 1970 From: Maarten Lankhorst Subject: Re: [PATCH] drm/irq: BUG_ON() -> WARN_ON() Date: Mon, 10 Nov 2014 12:33:58 +0100 Message-ID: <5460A2A6.1020904@canonical.com> References: <1415459779-30961-1-git-send-email-robdclark@gmail.com> <87sihrz5dm.fsf@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from youngberry.canonical.com (youngberry.canonical.com [91.189.89.112]) by gabe.freedesktop.org (Postfix) with ESMTP id 77A0D6E790 for ; Mon, 10 Nov 2014 03:34:00 -0800 (PST) In-Reply-To: <87sihrz5dm.fsf@intel.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: Jani Nikula , Rob Clark , dri-devel@lists.freedesktop.org, LKML List-Id: dri-devel@lists.freedesktop.org SGV5LAoKT3AgMTAtMTEtMTQgb20gMTI6MDEgc2NocmVlZiBKYW5pIE5pa3VsYToKPiBPbiBTYXQs IDA4IE5vdiAyMDE0LCBSb2IgQ2xhcmsgPHJvYmRjbGFya0BnbWFpbC5jb20+IHdyb3RlOgo+PiBM ZXQncyBtYWtlIHRoaW5ncyBhIGJpdCBlYXNpZXIgdG8gZGVidWcgd2hlbiB0aGluZ3MgZ28gYmFk IChwb3RlbnRpYWxseQo+PiB1bmRlciBjb25zb2xlX2xvY2spLgo+Pgo+PiBTaWduZWQtb2ZmLWJ5 OiBSb2IgQ2xhcmsgPHJvYmRjbGFya0BnbWFpbC5jb20+Cj4+IC0tLQo+PiAgZHJpdmVycy9ncHUv ZHJtL2RybV9pcnEuYyB8IDMgKystCj4+ICAxIGZpbGUgY2hhbmdlZCwgMiBpbnNlcnRpb25zKCsp LCAxIGRlbGV0aW9uKC0pCj4+Cj4+IGRpZmYgLS1naXQgYS9kcml2ZXJzL2dwdS9kcm0vZHJtX2ly cS5jIGIvZHJpdmVycy9ncHUvZHJtL2RybV9pcnEuYwo+PiBpbmRleCA1ZWYwM2MyLi5jNGVkZWE5 IDEwMDY0NAo+PiAtLS0gYS9kcml2ZXJzL2dwdS9kcm0vZHJtX2lycS5jCj4+ICsrKyBiL2RyaXZl cnMvZ3B1L2RybS9kcm1faXJxLmMKPj4gQEAgLTEwMjksNyArMTAyOSw4IEBAIHZvaWQgZHJtX3Zi bGFua19wdXQoc3RydWN0IGRybV9kZXZpY2UgKmRldiwgaW50IGNydGMpCj4+ICB7Cj4+ICAJc3Ry dWN0IGRybV92YmxhbmtfY3J0YyAqdmJsYW5rID0gJmRldi0+dmJsYW5rW2NydGNdOwo+PiAgCj4+ IC0JQlVHX09OKGF0b21pY19yZWFkKCZ2YmxhbmstPnJlZmNvdW50KSA9PSAwKTsKPj4gKwlpZiAo V0FSTl9PTihhdG9taWNfcmVhZCgmdmJsYW5rLT5yZWZjb3VudCkgPT0gMCkpCj4+ICsJCXJldHVy bjsKPiBXaGlsZSBJIGFwcHJvdmUgb2YgdGhlIGNoYW5nZSwgSSdkIGxpa2UgdG8gcHJvbW90ZSB0 aGUgdXNlIG9mIFdBUk4gd2l0aAo+IGEgbWVzc2FnZSBpbnN0ZWFkIG9mIFdBUk5fT04uIFNlZSBb MV0uIEluIGZhY3QgaXQgbGVhZCB0byB1cyByZWRlZmluaW5nCj4gV0FSTl9PTiBpbiBpOTE1IFsy XS4KSSBsb3ZlIHRoZSByZWRlZmluaXRpb24gb2YgV0FSTiwgYnV0IEkgdGhpbmsgdGhpcyBzaG91 bGQgbm90IGJlIG92ZXJyaWRkZW4gbG9jYWxseSwgaW5zdGVhZCBpdCBzaG91bGQgYmUgYSBrZXJu ZWwgZGVidWcgb3B0aW9uLgoKfk1hYXJ0ZW4KCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fCmRyaS1kZXZlbCBtYWlsaW5nIGxpc3QKZHJpLWRldmVsQGxpc3Rz LmZyZWVkZXNrdG9wLm9yZwpodHRwOi8vbGlzdHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlz dGluZm8vZHJpLWRldmVsCg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752595AbaKJLeC (ORCPT ); Mon, 10 Nov 2014 06:34:02 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:51019 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752577AbaKJLeA (ORCPT ); Mon, 10 Nov 2014 06:34:00 -0500 Message-ID: <5460A2A6.1020904@canonical.com> Date: Mon, 10 Nov 2014 12:33:58 +0100 From: Maarten Lankhorst User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Jani Nikula , Rob Clark , dri-devel@lists.freedesktop.org, LKML Subject: Re: [PATCH] drm/irq: BUG_ON() -> WARN_ON() References: <1415459779-30961-1-git-send-email-robdclark@gmail.com> <87sihrz5dm.fsf@intel.com> In-Reply-To: <87sihrz5dm.fsf@intel.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hey, Op 10-11-14 om 12:01 schreef Jani Nikula: > On Sat, 08 Nov 2014, Rob Clark wrote: >> Let's make things a bit easier to debug when things go bad (potentially >> under console_lock). >> >> Signed-off-by: Rob Clark >> --- >> drivers/gpu/drm/drm_irq.c | 3 ++- >> 1 file changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c >> index 5ef03c2..c4edea9 100644 >> --- a/drivers/gpu/drm/drm_irq.c >> +++ b/drivers/gpu/drm/drm_irq.c >> @@ -1029,7 +1029,8 @@ void drm_vblank_put(struct drm_device *dev, int crtc) >> { >> struct drm_vblank_crtc *vblank = &dev->vblank[crtc]; >> >> - BUG_ON(atomic_read(&vblank->refcount) == 0); >> + if (WARN_ON(atomic_read(&vblank->refcount) == 0)) >> + return; > While I approve of the change, I'd like to promote the use of WARN with > a message instead of WARN_ON. See [1]. In fact it lead to us redefining > WARN_ON in i915 [2]. I love the redefinition of WARN, but I think this should not be overridden locally, instead it should be a kernel debug option. ~Maarten