From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jerome Glisse Subject: Re: [RFC PATCH 00/13] SVM (share virtual memory) with HMM in nouveau Date: Tue, 13 Mar 2018 10:31:00 -0400 Message-ID: <20180313143100.GC3828@redhat.com> References: <20180310032141.6096-1-jglisse@redhat.com> <20180312173009.GN8589@phenom.ffwll.local> <20180312175057.GC4214@redhat.com> <39139ff7-76ad-960c-53f6-46b57525b733@nvidia.com> <20180313132940.GB3304@bombadil.infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: <20180313132940.GB3304-PfSpb0PWhxZc2C7mugBRk2EX/6BAtgUQ@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: nouveau-bounces-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org Sender: "Nouveau" To: Matthew Wilcox Cc: Ralph Campbell , "Bridgman, John" , Felix Kuehling , dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, Evgeny Baskakov , nouveau-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org, christian.koenig-5C7GfCeVMHo@public.gmane.org List-Id: nouveau.vger.kernel.org T24gVHVlLCBNYXIgMTMsIDIwMTggYXQgMDY6Mjk6NDBBTSAtMDcwMCwgTWF0dGhldyBXaWxjb3gg d3JvdGU6Cj4gT24gTW9uLCBNYXIgMTIsIDIwMTggYXQgMTE6MTQ6NDdQTSAtMDcwMCwgSm9obiBI dWJiYXJkIHdyb3RlOgo+ID4gWWVzLCBvbiBOVklESUEgR1BVcywgdGhlIEhvc3QvRklGTyB1bml0 IGlzIGxpbWl0ZWQgdG8gNDAtYml0IGFkZHJlc3Nlcywgc28KPiA+IHRoaW5ncyBzdWNoIGFzIHRo ZSBmb2xsb3dpbmcgbmVlZCB0byBiZSBiZWxvdyAoMSA8PCA0MCksIGFuZCBhbHNvIGFjY2Vzc2li bGUgCj4gPiB0byBib3RoIENQVSAodXNlciBzcGFjZSkgYW5kIEdQVSBoYXJkd2FyZS4gCj4gPiAg ICAgLS0gY29tbWFuZCBidWZmZXJzIChDUFUgdXNlciBzcGFjZSBkcml2ZXIgZmlsbHMgdGhlbSwg R1BVIGNvbnN1bWVzIHRoZW0pLCAKPiA+ICAgICAtLSBzZW1hcGhvcmVzIChoZXJlLCBhIEdQVS1j ZW50cmljIHRlcm0sIHJhdGhlciB0aGFuIE9TLXR5cGU6IHRoZXNlIGFyZQo+ID4gICAgICAgIG1l bW9yeSBsb2NhdGlvbnMgdGhhdCwgZm9yIGV4YW1wbGUsIHRoZSBHUFUgaGFyZHdhcmUgbWlnaHQg d3JpdGUgdG8sIGluCj4gPiAgICAgICAgb3JkZXIgdG8gaW5kaWNhdGUgd29yayBjb21wbGV0aW9u OyB0aGVyZSBhcmUgb3RoZXIgdXNlcyBhcyB3ZWxsKSwgCj4gPiAgICAgLS0gYSBmZXcgb3RoZXIg dGhpbmdzIG1vc3QgbGlrZWx5ICh0aGlzIGlzIG5vdCBhIGNvbXBsZXRlIGxpc3QpLgo+IAo+IElz IHRoYXQgYSA0MC1iaXQgdmlydHVhbCBhZGRyZXNzIGxpbWl0IG9yIHBoeXNpY2FsIGFkZHJlc3Mg bGltaXQ/ICBJJ20KPiBubyBsb25nZXIgc3VyZSB3aG8gaXMgYWRkcmVzc2luZyB3aGF0IG1lbW9y eSB0aHJvdWdoIHdoYXQgbWVjaGFuaXNtIDstKQo+IAoKVmlydHVhbCBhZGRyZXNzIGxpbWl0LCB0 aG9zZSBvYmplY3QgZ2V0IG1hcHBlZCBpbnRvIEdQVSBwYWdlIHRhYmxlIGJ1dAp0aGUgcmVnaXN0 ZXIvc3RydWN0dXJlIGZpZWxkcyB3aGVyZSB5b3UgcHJvZ3JhbSB0aG9zZSBvYmplY3QncyBhZGRy ZXNzCm9ubHkgYXJlIDMyYml0cyAodGhlIHZpcnR1YWwgYWRkcmVzcyBpcyBzaGlmdGVkIGJ5IDhi aXRzIGZvciBhbGlnbm1lbnQpLgoKQ2hlZXJzLApKw6lyw7RtZQpfX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fXwpOb3V2ZWF1IG1haWxpbmcgbGlzdApOb3V2ZWF1 QGxpc3RzLmZyZWVkZXNrdG9wLm9yZwpodHRwczovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWls bWFuL2xpc3RpbmZvL25vdXZlYXUK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f199.google.com (mail-qt0-f199.google.com [209.85.216.199]) by kanga.kvack.org (Postfix) with ESMTP id E5B8F6B026F for ; Tue, 13 Mar 2018 10:31:04 -0400 (EDT) Received: by mail-qt0-f199.google.com with SMTP id v89so14903875qte.21 for ; Tue, 13 Mar 2018 07:31:04 -0700 (PDT) Received: from mx1.redhat.com (mx3-rdu2.redhat.com. [66.187.233.73]) by mx.google.com with ESMTPS id c25si279211qkm.448.2018.03.13.07.31.04 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 13 Mar 2018 07:31:04 -0700 (PDT) Date: Tue, 13 Mar 2018 10:31:00 -0400 From: Jerome Glisse Subject: Re: [RFC PATCH 00/13] SVM (share virtual memory) with HMM in nouveau Message-ID: <20180313143100.GC3828@redhat.com> References: <20180310032141.6096-1-jglisse@redhat.com> <20180312173009.GN8589@phenom.ffwll.local> <20180312175057.GC4214@redhat.com> <39139ff7-76ad-960c-53f6-46b57525b733@nvidia.com> <20180313132940.GB3304@bombadil.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20180313132940.GB3304@bombadil.infradead.org> Sender: owner-linux-mm@kvack.org List-ID: To: Matthew Wilcox Cc: John Hubbard , christian.koenig@amd.com, dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org, Evgeny Baskakov , linux-mm@kvack.org, Ralph Campbell , Felix Kuehling , "Bridgman, John" On Tue, Mar 13, 2018 at 06:29:40AM -0700, Matthew Wilcox wrote: > On Mon, Mar 12, 2018 at 11:14:47PM -0700, John Hubbard wrote: > > Yes, on NVIDIA GPUs, the Host/FIFO unit is limited to 40-bit addresses, so > > things such as the following need to be below (1 << 40), and also accessible > > to both CPU (user space) and GPU hardware. > > -- command buffers (CPU user space driver fills them, GPU consumes them), > > -- semaphores (here, a GPU-centric term, rather than OS-type: these are > > memory locations that, for example, the GPU hardware might write to, in > > order to indicate work completion; there are other uses as well), > > -- a few other things most likely (this is not a complete list). > > Is that a 40-bit virtual address limit or physical address limit? I'm > no longer sure who is addressing what memory through what mechanism ;-) > Virtual address limit, those object get mapped into GPU page table but the register/structure fields where you program those object's address only are 32bits (the virtual address is shifted by 8bits for alignment). Cheers, Jerome