Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756208AbaGWOFc (ORCPT ); Wed, 23 Jul 2014 10:05:32 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:49178 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754275AbaGWOFb (ORCPT ); Wed, 23 Jul 2014 10:05:31 -0400 Message-ID: <53CFC121.6040109@canonical.com> Date: Wed, 23 Jul 2014 16:05:21 +0200 From: Maarten Lankhorst User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: =?UTF-8?B?Q2hyaXN0aWFuIEvDtm5pZw==?= , Daniel Vetter CC: =?UTF-8?B?Q2hyaXN0aWFuIEvDtm5pZw==?= , Thomas Hellstrom , nouveau , LKML , dri-devel , Ben Skeggs , "Deucher, Alexander" Subject: Re: [Nouveau] [PATCH 09/17] drm/radeon: use common fence implementation for fences References: <20140709093124.11354.3774.stgit@patser> <53CF5EFE.6070307@canonical.com> <53CF63C2.7070407@vodafone.de> <53CF6622.6060803@amd.com> <53CF699D.9070902@canonical.com> <53CF6B18.5070107@vodafone.de> <53CF7035.2060808@amd.com> <53CF7191.2090008@canonical.com> <53CF765E.7020802@vodafone.de> <53CF8010.9060809@amd.com> <53CF822E.7050601@amd.com> <53CF84C7.2020507@vodafone.de> <53CF8693.1040006@canonical.com> <53CF8AB1.2000009@amd.com> <53CFAC38.9050501@amd.com> <53CFB5C2.7060207@canonical.com> In-Reply-To: <53CFB5C2.7060207@canonical.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org op 23-07-14 15:16, Maarten Lankhorst schreef: > op 23-07-14 14:36, Christian König schreef: >> Am 23.07.2014 12:52, schrieb Daniel Vetter: >>> On Wed, Jul 23, 2014 at 12:13 PM, Christian König >>> wrote: >>>>> And the dma-buf would still have fences belonging to both drivers, and it >>>>> would still call from outside the driver. >>>> Calling from outside the driver is fine as long as the driver can do >>>> everything necessary to complete it's work and isn't forced into any ugly >>>> hacks and things that are not 100% reliable. >>>> >>>> So I don't see much other approach as integrating recovery code for not >>>> firing interrupts and some kind of lockup handling into the fence code as >>>> well. >>> That approach doesn't really work at that well since every driver has >>> it's own reset semantics. And we're trying to move away from global >>> reset to fine-grained reset. So stop-the-world reset is out of >>> fashion, at least for i915. As you said, reset is normal in gpus and >>> we're trying to make reset less invasive. I really don't see a point >>> in imposing a reset scheme upon all drivers and I think you have about >>> as much motivation to convert radeon to the scheme used by i915 as >>> I'll have for converting to the one used by radeon. If it would fit at >>> all. >> Oh my! No, I didn't wanted to suggest any global reset infrastructure. >> >> My idea was more that the fence framework provides a fence->process_signaling callback that is periodically called after enable_signaling is called to trigger manual signal processing in the driver. >> >> This would both be suitable as a fallback in case of not working interrupts as well as a chance for any driver to do necessary lockup handling. > I managed to do it without needing it to be part of the interface? I'm not sure whether radeon_fence_driver_recheck needs exclusive_lock, but if so it's a small change.. > > diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h > index 7fbfd41479f1..51b646b9c8bb 100644 > --- a/drivers/gpu/drm/radeon/radeon.h > +++ b/drivers/gpu/drm/radeon/radeon.h > @@ -345,6 +345,9 @@ struct radeon_fence_driver { > uint64_t sync_seq[RADEON_NUM_RINGS]; > atomic64_t last_seq; > bool initialized; > + struct delayed_work work; > + struct radeon_device *rdev; > + unsigned ring; > }; > > struct radeon_fence_cb { > diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c > index da83f36dd708..955c825946ad 100644 > --- a/drivers/gpu/drm/radeon/radeon_fence.c > +++ b/drivers/gpu/drm/radeon/radeon_fence.c > @@ -231,6 +231,9 @@ static bool __radeon_fence_process(struct radeon_device *rdev, int ring) > } > } while (atomic64_xchg(&rdev->fence_drv[ring].last_seq, seq) > seq); > > + if (!wake && last_seq < last_emitted) > + schedule_delayed_work(&rdev->fence_drv[ring].work, jiffies_to_msecs(10)); > + > When trying this: if (seq < last_emitted) is probably a better check. ~Maarten -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/