From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hildenbrand Subject: Re: [PATCH RFC] mm/memory_hotplug: Introduce memory block types Date: Fri, 5 Oct 2018 09:37:39 +0200 Message-ID: References: <20181001084038.GD18290@dhcp22.suse.cz> <20181002134734.GT18290@dhcp22.suse.cz> <98fb8d65-b641-2225-f842-8804c6f79a06@redhat.com> <8736tndubn.fsf@vitty.brq.redhat.com> <20181003134444.GH4714@dhcp22.suse.cz> <87zhvvcf3b.fsf@vitty.brq.redhat.com> <49456818-238e-2d95-9df6-d1934e9c8b53@linux.intel.com> <87tvm3cd5w.fsf@vitty.brq.redhat.com> <06a35970-e478-18f8-eae6-4022925a5192@redhat.com> <20181004061938.GB22173@dhcp22.suse.cz> <20181004172807.1eef3a6b@kitsune.suse.cz> <14992b68-5402-9168-0050-b3c6ac4a8c90@redhat.com> <20181004195010.3616fc40@kitsune.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20181004195010.3616fc40@kitsune.suse.cz> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: driverdev-devel-bounces@linuxdriverproject.org Sender: "devel" To: =?UTF-8?Q?Michal_Such=c3=a1nek?= Cc: Kate Stewart , Rich Felker , linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, Peter Zijlstra , Joonsoo Kim , Dave Hansen , Heiko Carstens , Michal Hocko , linux-mm@kvack.org, Paul Mackerras , "H. Peter Anvin" , Rashmica Gupta , Dan Williams , Stephen Rothwell , Michael Neuling , Stephen Hemminger , Yoshinori Sato , linux-acpi@vger.kernel.org, Ingo Molnar , xen-devel@lists.xenproject.org, Len Brown , Pavel Tatashin , Rob Herring , mike.travis@hpe.com List-Id: linux-acpi@vger.kernel.org T24gMDQvMTAvMjAxOCAxOTo1MCwgTWljaGFsIFN1Y2jDoW5layB3cm90ZToKPiBPbiBUaHUsIDQg T2N0IDIwMTggMTc6NDU6MTMgKzAyMDAKPiBEYXZpZCBIaWxkZW5icmFuZCA8ZGF2aWRAcmVkaGF0 LmNvbT4gd3JvdGU6Cj4gCj4+IE9uIDA0LzEwLzIwMTggMTc6MjgsIE1pY2hhbCBTdWNow6FuZWsg d3JvdGU6Cj4gCj4+Pgo+Pj4gVGhlIHN0YXRlIG9mIHRoZSBhcnQgaXMgdG8gZGV0ZXJtaW5lIHdo YXQgdG8gZG8gd2l0aCBob3RwbHVnZ2VkCj4+PiBtZW1vcnkgaW4gdXNlcnNwYWNlIGJhc2VkIG9u IHBsYXRmb3JtIGFuZCB2aXJ0dWFsaXphdGlvbiB0eXBlLiAgCj4+Cj4+IEV4YWN0bHkuCj4+Cj4+ Pgo+Pj4gQ2hhbmdpbmcgdGhlIGRlZmF1bHQgdG8gZGVwZW5kIG9uIHRoZSBkcml2ZXIgdGhhdCBh ZGRlZCB0aGUgbWVtb3J5Cj4+PiByYXRoZXIgdGhhbiBwbGF0Zm9ybSB0eXBlIHNob3VsZCBzb2x2 ZSB0aGUgaXNzdWUgb2YgVk1zIGdyb3dpbmcKPj4+IGRpZmZlcmVudCB0eXBlcyBvZiBtZW1vcnkg ZGV2aWNlIGVtdWxhdGlvbi4gIAo+Pgo+PiBZZXMsIG15IG9yaWdpbmFsIHByb3Bvc2FsICh0aGlz IHBhdGNoKSB3YXMgdG8gaGFuZGxlIGl0IGluIHRoZSBrZXJuZWwKPj4gZm9yIGtub3duIHR5cGVz LiBCdXQgYXMgd2UgbGVhcm5lZCwgdGhlcmUgbWlnaHQgYmUgc29tZSB1c2UgY2FzZXMgdGhhdAo+ PiBtaWdodCBzdGlsbCByZXF1aXJlIHRvIG1ha2UgYSBkZWNpc2lvbiBpbiB1c2VyIHNwYWNlLgo+ Pgo+PiBTbyBwcm92aWRpbmcgdGhlIHVzZXIgc3BhY2UgZWl0aGVyIHdpdGggc29tZSB0eXBlIGhp bnQgKGF1dG8tb25saW5lCj4+IHZzLiBzdGFuZGJ5KSBvciB0aGUgZHJpdmVyIHRoYXQgYWRkZWQg aXQgKHN5c3RlbSB2cy4gaHlwZXItdiAuLi4pCj4+IHdvdWxkIHNvbHZlIHRoZSBpc3N1ZS4KPiAK PiBJcyB0aGF0IG5vdCBhdmFpbGFibGUgaW4gdGhlIHVkZXYgZXZlbnQ/Cj4gCgpOb3QgdGhhdCBJ IGFtIGF3YXJlLiBNZW1vcnkgYmxvY2tzICJkZXZpY2VzIiBoYXZlIG5vIGRyaXZlcnMuCgpscyAt bGEgL3N5cy9kZXZpY2VzL3N5c3RlbS9tZW1vcnkvbWVtb3J5MC9zdWJzeXN0ZW0vZHJpdmVycwp0 b3RhbCAwCgooYWRkX21lbW9yeSgpL2FkZF9tZW1vcnlfcmVzb3VyY2UoKSBjcmVhdGVzIHRoZSBt ZW1vcnkgYmxvY2sgZGV2aWNlcwp3aGVuIGNhbGxlZCBmcm9tIGEgZHJpdmVyKQoKCj4gVGhhbmtz Cj4gCj4gTWljaGFsCj4gCgoKLS0gCgpUaGFua3MsCgpEYXZpZCAvIGRoaWxkZW5iCl9fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmRldmVsIG1haWxpbmcgbGlz dApkZXZlbEBsaW51eGRyaXZlcnByb2plY3Qub3JnCmh0dHA6Ly9kcml2ZXJkZXYubGludXhkcml2 ZXJwcm9qZWN0Lm9yZy9tYWlsbWFuL2xpc3RpbmZvL2RyaXZlcmRldi1kZXZlbAo= From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt1-f198.google.com (mail-qt1-f198.google.com [209.85.160.198]) by kanga.kvack.org (Postfix) with ESMTP id 3BEA66B026D for ; Fri, 5 Oct 2018 03:37:55 -0400 (EDT) Received: by mail-qt1-f198.google.com with SMTP id j60-v6so3703627qtb.8 for ; Fri, 05 Oct 2018 00:37:55 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id o69-v6si3380701qkh.108.2018.10.05.00.37.54 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 05 Oct 2018 00:37:54 -0700 (PDT) Subject: Re: [PATCH RFC] mm/memory_hotplug: Introduce memory block types References: <20181001084038.GD18290@dhcp22.suse.cz> <20181002134734.GT18290@dhcp22.suse.cz> <98fb8d65-b641-2225-f842-8804c6f79a06@redhat.com> <8736tndubn.fsf@vitty.brq.redhat.com> <20181003134444.GH4714@dhcp22.suse.cz> <87zhvvcf3b.fsf@vitty.brq.redhat.com> <49456818-238e-2d95-9df6-d1934e9c8b53@linux.intel.com> <87tvm3cd5w.fsf@vitty.brq.redhat.com> <06a35970-e478-18f8-eae6-4022925a5192@redhat.com> <20181004061938.GB22173@dhcp22.suse.cz> <20181004172807.1eef3a6b@kitsune.suse.cz> <14992b68-5402-9168-0050-b3c6ac4a8c90@redhat.com> <20181004195010.3616fc40@kitsune.suse.cz> From: David Hildenbrand Message-ID: Date: Fri, 5 Oct 2018 09:37:39 +0200 MIME-Version: 1.0 In-Reply-To: <20181004195010.3616fc40@kitsune.suse.cz> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: =?UTF-8?Q?Michal_Such=c3=a1nek?= Cc: Kate Stewart , Rich Felker , linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, Peter Zijlstra , Dave Hansen , Heiko Carstens , Michal Hocko , linux-mm@kvack.org, Paul Mackerras , "H. Peter Anvin" , Rashmica Gupta , Boris Ostrovsky , Stephen Rothwell , Michael Neuling , Stephen Hemminger , Yoshinori Sato , Vitaly Kuznetsov , linux-acpi@vger.kernel.org, Ingo Molnar , xen-devel@lists.xenproject.org, Rob Herring , Len Brown , Pavel Tatashin , linux-s390@vger.kernel.org, "mike.travis@hpe.com" , Haiyang Zhang , =?UTF-8?Q?Jonathan_Neusch=c3=a4fer?= , Nicholas Piggin , Joe Perches , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Mike Rapoport , Borislav Petkov , Andy Lutomirski , Dan Williams , Andrew Morton , Oscar Salvador , Juergen Gross , Tony Luck , Mathieu Malaterre , Greg Kroah-Hartman , "Rafael J. Wysocki" , linux-kernel@vger.kernel.org, Fenghua Yu , Mauricio Faria de Oliveira , Thomas Gleixner , Philippe Ombredanne , Martin Schwidefsky , devel@linuxdriverproject.org, Joonsoo Kim , linuxppc-dev@lists.ozlabs.org, "Kirill A. Shutemov" On 04/10/2018 19:50, Michal SuchA!nek wrote: > On Thu, 4 Oct 2018 17:45:13 +0200 > David Hildenbrand wrote: > >> On 04/10/2018 17:28, Michal SuchA!nek wrote: > >>> >>> The state of the art is to determine what to do with hotplugged >>> memory in userspace based on platform and virtualization type. >> >> Exactly. >> >>> >>> Changing the default to depend on the driver that added the memory >>> rather than platform type should solve the issue of VMs growing >>> different types of memory device emulation. >> >> Yes, my original proposal (this patch) was to handle it in the kernel >> for known types. But as we learned, there might be some use cases that >> might still require to make a decision in user space. >> >> So providing the user space either with some type hint (auto-online >> vs. standby) or the driver that added it (system vs. hyper-v ...) >> would solve the issue. > > Is that not available in the udev event? > Not that I am aware. Memory blocks "devices" have no drivers. ls -la /sys/devices/system/memory/memory0/subsystem/drivers total 0 (add_memory()/add_memory_resource() creates the memory block devices when called from a driver) > Thanks > > Michal > -- Thanks, David / dhildenb From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 24B60C00449 for ; Fri, 5 Oct 2018 07:53:48 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9185D2064D for ; Fri, 5 Oct 2018 07:53:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9185D2064D Authentication-Results: mail.kernel.org; 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Fri, 5 Oct 2018 07:37:52 +0000 (UTC) Received: from [10.36.116.131] (ovpn-116-131.ams2.redhat.com [10.36.116.131]) by smtp.corp.redhat.com (Postfix) with ESMTP id 40AAD2E02F; Fri, 5 Oct 2018 07:37:40 +0000 (UTC) Subject: Re: [PATCH RFC] mm/memory_hotplug: Introduce memory block types To: =?UTF-8?Q?Michal_Such=c3=a1nek?= References: <20181001084038.GD18290@dhcp22.suse.cz> <20181002134734.GT18290@dhcp22.suse.cz> <98fb8d65-b641-2225-f842-8804c6f79a06@redhat.com> <8736tndubn.fsf@vitty.brq.redhat.com> <20181003134444.GH4714@dhcp22.suse.cz> <87zhvvcf3b.fsf@vitty.brq.redhat.com> <49456818-238e-2d95-9df6-d1934e9c8b53@linux.intel.com> <87tvm3cd5w.fsf@vitty.brq.redhat.com> <06a35970-e478-18f8-eae6-4022925a5192@redhat.com> <20181004061938.GB22173@dhcp22.suse.cz> <20181004172807.1eef3a6b@kitsune.suse.cz> <14992b68-5402-9168-0050-b3c6ac4a8c90@redhat.com> <20181004195010.3616fc40@kitsune.suse.cz> From: David Hildenbrand Openpgp: preference=signencrypt Autocrypt: addr=david@redhat.com; prefer-encrypt=mutual; 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Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.0 MIME-Version: 1.0 In-Reply-To: <20181004195010.3616fc40@kitsune.suse.cz> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Fri, 05 Oct 2018 07:37:53 +0000 (UTC) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kate Stewart , Rich Felker , linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, Peter Zijlstra , Joonsoo Kim , Dave Hansen , Heiko Carstens , Michal Hocko , linux-mm@kvack.org, Paul Mackerras , "H. Peter Anvin" , Rashmica Gupta , Dan Williams , Stephen Rothwell , Michael Neuling , Stephen Hemminger , Yoshinori Sato , linux-acpi@vger.kernel.org, Ingo Molnar , xen-devel@lists.xenproject.org, Len Brown , Pavel Tatashin , Rob Herring , "mike.travis@hpe.com" , Haiyang Zhang , Philippe Ombredanne , =?UTF-8?Q?Jonathan_Neusch=c3=a4fer?= , Nicholas Piggin , Martin Schwidefsky , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Mike Rapoport , Borislav Petkov , Andy Lutomirski , Boris Ostrovsky , Andrew Morton , Oscar Salvador , Juergen Gross , Tony Luck , Mathieu Malaterre , linux-s390@vger.kernel.org, "Rafael J. Wysocki" , linux-kernel@vger.kernel.org, Fenghua Yu , Mauricio Faria de Oliveira , Thomas Gleixner , Greg Kroah-Hartman , Joe Perches , devel@linuxdriverproject.org, Vitaly Kuznetsov , linuxppc-dev@lists.ozlabs.org, "Kirill A. Shutemov" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 04/10/2018 19:50, Michal Suchánek wrote: > On Thu, 4 Oct 2018 17:45:13 +0200 > David Hildenbrand wrote: > >> On 04/10/2018 17:28, Michal Suchánek wrote: > >>> >>> The state of the art is to determine what to do with hotplugged >>> memory in userspace based on platform and virtualization type. >> >> Exactly. >> >>> >>> Changing the default to depend on the driver that added the memory >>> rather than platform type should solve the issue of VMs growing >>> different types of memory device emulation. >> >> Yes, my original proposal (this patch) was to handle it in the kernel >> for known types. But as we learned, there might be some use cases that >> might still require to make a decision in user space. >> >> So providing the user space either with some type hint (auto-online >> vs. standby) or the driver that added it (system vs. hyper-v ...) >> would solve the issue. > > Is that not available in the udev event? > Not that I am aware. Memory blocks "devices" have no drivers. ls -la /sys/devices/system/memory/memory0/subsystem/drivers total 0 (add_memory()/add_memory_resource() creates the memory block devices when called from a driver) > Thanks > > Michal > -- Thanks, David / dhildenb