From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755573AbaGVPR6 (ORCPT ); Tue, 22 Jul 2014 11:17:58 -0400 Received: from mail-ie0-f177.google.com ([209.85.223.177]:62804 "EHLO mail-ie0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751105AbaGVPR5 convert rfc822-to-8bit (ORCPT ); Tue, 22 Jul 2014 11:17:57 -0400 MIME-Version: 1.0 X-Originating-IP: [84.73.67.144] In-Reply-To: <53CE6AFA.1060807@vodafone.de> References: <20140709093124.11354.3774.stgit@patser> <20140709122953.11354.46381.stgit@patser> <53CE2421.5040906@amd.com> <20140722114607.GL15237@phenom.ffwll.local> <20140722115737.GN15237@phenom.ffwll.local> <53CE56ED.4040109@vodafone.de> <20140722132652.GO15237@phenom.ffwll.local> <53CE6AFA.1060807@vodafone.de> Date: Tue, 22 Jul 2014 17:17:56 +0200 Message-ID: Subject: Re: [Nouveau] [PATCH 09/17] drm/radeon: use common fence implementation for fences From: Daniel Vetter To: =?UTF-8?Q?Christian_K=C3=B6nig?= Cc: =?UTF-8?Q?Christian_K=C3=B6nig?= , Dave Airlie , Maarten Lankhorst , Thomas Hellstrom , nouveau , LKML , dri-devel , Ben Skeggs , "Deucher, Alexander" 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 On Tue, Jul 22, 2014 at 3:45 PM, Christian König wrote: >> Would that be something you can agree to? > > > No, the whole enable_signaling stuff should go away. No callback from the > driver into the fence code, only the other way around. > > fence->signaled as well as fence->wait should become mandatory and only > called from process context without holding any locks, neither atomic nor > any mutex/semaphore (rcu might be ok). So for the enable_signaling, that's optional already. It's only for drivers that don't want to keep interrupts enabled all the time. You can opt out of that easily. Wrt holding no locks at all while calling into any fence functions, that's just not going to work out. The point here is to make different drivers work together and we can rework all the ttm and i915 code to work locklessly in all cases where they need to wait for someone to complete rendering. Or at least I don't think that's feasible. So if you insist that no one might call into radeon code then we simply need to exclude radeon from participating in any shared fencing. But that's a bit pointless. >> Like I've said I think restricting the insanity other people are willing >> to live with just because you don't like it isn't right. But it is >> certainly right for you to insist on not being forced into any such >> design. I think the above would achieve this. > > > I don't think so. If it's just me I would say that I'm just to cautious and > the idea is still save to apply to the whole kernel. > > But since Dave, Jerome and Ben seems to have similar concerns I think we > need to agree to a minimum and save interface for all drivers. Well I haven't yet seen a proposal that actually works. From an intel pov I don't care that much since we don't care about desktop prime, so if radeon/nouveau don't want to do that, meh. Imo the design as-is is fairly sound, and as simple as it can get given the requirements. I haven't heard an argument convincing me otherwise, so I guess we won't have prime support on linux that actually works, ever. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH 09/17] drm/radeon: use common fence implementation for fences Date: Tue, 22 Jul 2014 17:17:56 +0200 Message-ID: References: <20140709093124.11354.3774.stgit@patser> <20140709122953.11354.46381.stgit@patser> <53CE2421.5040906@amd.com> <20140722114607.GL15237@phenom.ffwll.local> <20140722115737.GN15237@phenom.ffwll.local> <53CE56ED.4040109@vodafone.de> <20140722132652.GO15237@phenom.ffwll.local> <53CE6AFA.1060807@vodafone.de> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <53CE6AFA.1060807-ANTagKRnAhcb1SvskN2V4Q@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: nouveau-bounces-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Sender: "Nouveau" To: =?UTF-8?Q?Christian_K=C3=B6nig?= Cc: Thomas Hellstrom , nouveau , LKML , dri-devel , "Deucher, Alexander" , Ben Skeggs , =?UTF-8?Q?Christian_K=C3=B6nig?= List-Id: nouveau.vger.kernel.org T24gVHVlLCBKdWwgMjIsIDIwMTQgYXQgMzo0NSBQTSwgQ2hyaXN0aWFuIEvDtm5pZwo8ZGVhdGhz aW1wbGVAdm9kYWZvbmUuZGU+IHdyb3RlOgo+PiBXb3VsZCB0aGF0IGJlIHNvbWV0aGluZyB5b3Ug Y2FuIGFncmVlIHRvPwo+Cj4KPiBObywgdGhlIHdob2xlIGVuYWJsZV9zaWduYWxpbmcgc3R1ZmYg c2hvdWxkIGdvIGF3YXkuIE5vIGNhbGxiYWNrIGZyb20gdGhlCj4gZHJpdmVyIGludG8gdGhlIGZl bmNlIGNvZGUsIG9ubHkgdGhlIG90aGVyIHdheSBhcm91bmQuCj4KPiBmZW5jZS0+c2lnbmFsZWQg YXMgd2VsbCBhcyBmZW5jZS0+d2FpdCBzaG91bGQgYmVjb21lIG1hbmRhdG9yeSBhbmQgb25seQo+ IGNhbGxlZCBmcm9tIHByb2Nlc3MgY29udGV4dCB3aXRob3V0IGhvbGRpbmcgYW55IGxvY2tzLCBu ZWl0aGVyIGF0b21pYyBub3IKPiBhbnkgbXV0ZXgvc2VtYXBob3JlIChyY3UgbWlnaHQgYmUgb2sp LgoKU28gZm9yIHRoZSBlbmFibGVfc2lnbmFsaW5nLCB0aGF0J3Mgb3B0aW9uYWwgYWxyZWFkeS4g SXQncyBvbmx5IGZvcgpkcml2ZXJzIHRoYXQgZG9uJ3Qgd2FudCB0byBrZWVwIGludGVycnVwdHMg ZW5hYmxlZCBhbGwgdGhlIHRpbWUuIFlvdQpjYW4gb3B0IG91dCBvZiB0aGF0IGVhc2lseS4KCldy dCBob2xkaW5nIG5vIGxvY2tzIGF0IGFsbCB3aGlsZSBjYWxsaW5nIGludG8gYW55IGZlbmNlIGZ1 bmN0aW9ucywKdGhhdCdzIGp1c3Qgbm90IGdvaW5nIHRvIHdvcmsgb3V0LiBUaGUgcG9pbnQgaGVy ZSBpcyB0byBtYWtlIGRpZmZlcmVudApkcml2ZXJzIHdvcmsgdG9nZXRoZXIgYW5kIHdlIGNhbiBy ZXdvcmsgYWxsIHRoZSB0dG0gYW5kIGk5MTUgY29kZSB0bwp3b3JrIGxvY2tsZXNzbHkgaW4gYWxs IGNhc2VzIHdoZXJlIHRoZXkgbmVlZCB0byB3YWl0IGZvciBzb21lb25lIHRvCmNvbXBsZXRlIHJl bmRlcmluZy4gT3IgYXQgbGVhc3QgSSBkb24ndCB0aGluayB0aGF0J3MgZmVhc2libGUuIFNvIGlm CnlvdSBpbnNpc3QgdGhhdCBubyBvbmUgbWlnaHQgY2FsbCBpbnRvIHJhZGVvbiBjb2RlIHRoZW4g d2Ugc2ltcGx5IG5lZWQKdG8gZXhjbHVkZSByYWRlb24gZnJvbSBwYXJ0aWNpcGF0aW5nIGluIGFu eSBzaGFyZWQgZmVuY2luZy4gQnV0IHRoYXQncwphIGJpdCBwb2ludGxlc3MuCgo+PiBMaWtlIEkn dmUgc2FpZCBJIHRoaW5rIHJlc3RyaWN0aW5nIHRoZSBpbnNhbml0eSBvdGhlciBwZW9wbGUgYXJl IHdpbGxpbmcKPj4gdG8gbGl2ZSB3aXRoIGp1c3QgYmVjYXVzZSB5b3UgZG9uJ3QgbGlrZSBpdCBp c24ndCByaWdodC4gQnV0IGl0IGlzCj4+IGNlcnRhaW5seSByaWdodCBmb3IgeW91IHRvIGluc2lz dCBvbiBub3QgYmVpbmcgZm9yY2VkIGludG8gYW55IHN1Y2gKPj4gZGVzaWduLiBJIHRoaW5rIHRo ZSBhYm92ZSB3b3VsZCBhY2hpZXZlIHRoaXMuCj4KPgo+IEkgZG9uJ3QgdGhpbmsgc28uIElmIGl0 J3MganVzdCBtZSBJIHdvdWxkIHNheSB0aGF0IEknbSBqdXN0IHRvIGNhdXRpb3VzIGFuZAo+IHRo ZSBpZGVhIGlzIHN0aWxsIHNhdmUgdG8gYXBwbHkgdG8gdGhlIHdob2xlIGtlcm5lbC4KPgo+IEJ1 dCBzaW5jZSBEYXZlLCBKZXJvbWUgYW5kIEJlbiBzZWVtcyB0byBoYXZlIHNpbWlsYXIgY29uY2Vy bnMgSSB0aGluayB3ZQo+IG5lZWQgdG8gYWdyZWUgdG8gYSBtaW5pbXVtIGFuZCBzYXZlIGludGVy ZmFjZSBmb3IgYWxsIGRyaXZlcnMuCgpXZWxsIEkgaGF2ZW4ndCB5ZXQgc2VlbiBhIHByb3Bvc2Fs IHRoYXQgYWN0dWFsbHkgd29ya3MuIEZyb20gYW4gaW50ZWwKcG92IEkgZG9uJ3QgY2FyZSB0aGF0 IG11Y2ggc2luY2Ugd2UgZG9uJ3QgY2FyZSBhYm91dCBkZXNrdG9wIHByaW1lLCBzbwppZiByYWRl b24vbm91dmVhdSBkb24ndCB3YW50IHRvIGRvIHRoYXQsIG1laC4gSW1vIHRoZSBkZXNpZ24gYXMt aXMgaXMKZmFpcmx5IHNvdW5kLCBhbmQgYXMgc2ltcGxlIGFzIGl0IGNhbiBnZXQgZ2l2ZW4gdGhl IHJlcXVpcmVtZW50cy4gSQpoYXZlbid0IGhlYXJkIGFuICBhcmd1bWVudCBjb252aW5jaW5nIG1l IG90aGVyd2lzZSwgc28gSSBndWVzcyB3ZQp3b24ndCBoYXZlIHByaW1lIHN1cHBvcnQgb24gbGlu dXggdGhhdCBhY3R1YWxseSB3b3JrcywgZXZlci4KLURhbmllbAotLSAKRGFuaWVsIFZldHRlcgpT b2Z0d2FyZSBFbmdpbmVlciwgSW50ZWwgQ29ycG9yYXRpb24KKzQxICgwKSA3OSAzNjUgNTcgNDgg LSBodHRwOi8vYmxvZy5mZndsbC5jaApfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fXwpOb3V2ZWF1IG1haWxpbmcgbGlzdApOb3V2ZWF1QGxpc3RzLmZyZWVkZXNr dG9wLm9yZwpodHRwOi8vbGlzdHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vbm91 dmVhdQo=