[{"id":1772813,"web_url":"http://patchwork.ozlabs.org/comment/1772813/","msgid":"<1d5f2bb4-c330-98b9-bf1a-6024a9f9093d@ozlabs.ru>","list_archive_url":null,"date":"2017-09-21T13:39:25","subject":"Re: [Qemu-devel] [PATCH 2/3] memory: seek FlatView sharing\n\tcandidates among children subregions","submitter":{"id":7621,"url":"http://patchwork.ozlabs.org/api/people/7621/","name":"Alexey Kardashevskiy","email":"aik@ozlabs.ru"},"content":"On 21/09/17 22:07, Paolo Bonzini wrote:\n> A container can be used instead of an alias to allow switching between\n> multiple subregions. In this case we cannot directly share the\n> subregions (since they only belong to a single parent), but if the\n> subregions are aliases we can in turn walk those.\n> \n> While this does not reduce much the number of FlatViews that are created,\n> it makes it possible to share the PCI bus master FlatViews and their\n> AddressSpaceDispatch structures. For 112 virtio-net-pci devices, boot time\n> is reduced from 25 to 10 seconds and memory consumption from 1.4 to 1 G.\n> \n> Signed-off-by: Paolo Bonzini \n> ---\n> memory.c | 41 +++++++++++++++++++++++++++++++++++------\n> 1 file changed, 35 insertions(+), 6 deletions(-)\n> \n> diff --git a/memory.c b/memory.c\n> index 4952cc5d84..3207ae55e2 100644\n> --- a/memory.c\n> +++ b/memory.c\n> @@ -733,12 +733,41 @@ static void render_memory_region(FlatView *view,\n> \n> static MemoryRegion *memory_region_get_flatview_root(MemoryRegion *mr)\n> {\n> - while (mr->alias && !mr->alias_offset &&\n> - int128_ge(mr->size, mr->alias->size)) {\n> - /* The alias is included in its entirety. Use it as\n> - * the \"real\" root, so that we can share more FlatViews.\n> - */\n> - mr = mr->alias;\n> + while (mr->enabled) {\n> + if (mr->alias && !mr->alias_offset &&\n> + int128_ge(mr->size, mr->alias->size)) {\n> + /* The alias is included in its entirety. Use it as\n> + * the \"real\" root, so that we can share more FlatViews.\n> + */\n> + mr = mr->alias;\n> + continue;\n> + }\n> +\n> + if (!mr->terminates) {\n\nCan an MR have terminates==true and children by the same time? If so, what for?\n\n\n> + unsigned int found = 0;\n> + MemoryRegion *child, *next = NULL;\n> + QTAILQ_FOREACH(child, &mr->subregions, subregions_link) {\n> + if (child->enabled) {\n> + if (++found > 1) {\n> + next = NULL;\n> + break;\n> + }\n> + if (!child->addr && int128_ge(mr->size, child->size)) {\n\n\nAh, I tried this one but in v4's 18/18 (that hinting thing), did not work\nout but for a different reason.\n\n\n> + /* A child is included in its entirety. If it's the only\n> + * enabled one, use it in the hope of finding an alias down the\n> + * way. This will also let us share FlatViews.\n> + */\n> + next = child;\n> + }\n> + }\n> + }\n> + if (next) {\n> + mr = next;\n> + continue;\n> + }\n> + }\n> +\n> + break;\n> }\n> \n> return mr;\n>","headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=)","ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=ozlabs-ru.20150623.gappssmtp.com\n\theader.i=@ozlabs-ru.20150623.gappssmtp.com\n\theader.b=\"ReiG8YSH\"; dkim-atps=neutral"],"Received":["from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11])\n\t(using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xydGQ0Z9zz9ryr\n\tfor ;\n\tThu, 21 Sep 2017 23:47:42 +1000 (AEST)","from localhost ([::1]:53818 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t)\n\tid 1dv1pM-0006NA-8S\n\tfor incoming@patchwork.ozlabs.org; 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Linux x86_64; rv:52.0) Gecko/20100101\n\tThunderbird/52.2.1","MIME-Version":"1.0","In-Reply-To":"<20170921120751.3027-3-pbonzini@redhat.com>","Content-Type":"text/plain; charset=utf-8","Content-Language":"en-AU","Content-Transfer-Encoding":"7bit","X-detected-operating-system":"by eggs.gnu.org: Genre and OS details not\n\trecognized.","X-Received-From":"2607:f8b0:400e:c05::242","Subject":"Re: [Qemu-devel] [PATCH 2/3] memory: seek FlatView sharing\n\tcandidates among children subregions","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.21","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"\"Qemu-devel\"\n\t"}},{"id":1772819,"web_url":"http://patchwork.ozlabs.org/comment/1772819/","msgid":"","list_archive_url":null,"date":"2017-09-21T13:57:15","subject":"Re: [Qemu-devel] [PATCH 2/3] memory: seek FlatView sharing\n\tcandidates among children subregions","submitter":{"id":2701,"url":"http://patchwork.ozlabs.org/api/people/2701/","name":"Paolo Bonzini","email":"pbonzini@redhat.com"},"content":"On 21/09/2017 15:39, Alexey Kardashevskiy wrote:\n> On 21/09/17 22:07, Paolo Bonzini wrote:\n>> A container can be used instead of an alias to allow switching between\n>> multiple subregions. In this case we cannot directly share the\n>> subregions (since they only belong to a single parent), but if the\n>> subregions are aliases we can in turn walk those.\n>>\n>> While this does not reduce much the number of FlatViews that are created,\n>> it makes it possible to share the PCI bus master FlatViews and their\n>> AddressSpaceDispatch structures. For 112 virtio-net-pci devices, boot time\n>> is reduced from 25 to 10 seconds and memory consumption from 1.4 to 1 G.\n>>\n>> Signed-off-by: Paolo Bonzini \n>> ---\n>> memory.c | 41 +++++++++++++++++++++++++++++++++++------\n>> 1 file changed, 35 insertions(+), 6 deletions(-)\n>>\n>> diff --git a/memory.c b/memory.c\n>> index 4952cc5d84..3207ae55e2 100644\n>> --- a/memory.c\n>> +++ b/memory.c\n>> @@ -733,12 +733,41 @@ static void render_memory_region(FlatView *view,\n>> \n>> static MemoryRegion *memory_region_get_flatview_root(MemoryRegion *mr)\n>> {\n>> - while (mr->alias && !mr->alias_offset &&\n>> - int128_ge(mr->size, mr->alias->size)) {\n>> - /* The alias is included in its entirety. Use it as\n>> - * the \"real\" root, so that we can share more FlatViews.\n>> - */\n>> - mr = mr->alias;\n>> + while (mr->enabled) {\n>> + if (mr->alias && !mr->alias_offset &&\n>> + int128_ge(mr->size, mr->alias->size)) {\n>> + /* The alias is included in its entirety. Use it as\n>> + * the \"real\" root, so that we can share more FlatViews.\n>> + */\n>> + mr = mr->alias;\n>> + continue;\n>> + }\n>> +\n>> + if (!mr->terminates) {\n> \n> Can an MR have terminates==true and children by the same time? If so, what for?\n\nYes, children override the parent. But more important, !mr->terminates\nmeans that patch 3 doesn't think that MR produces an empty FlatView.\n\n> \n>> + unsigned int found = 0;\n>> + MemoryRegion *child, *next = NULL;\n>> + QTAILQ_FOREACH(child, &mr->subregions, subregions_link) {\n>> + if (child->enabled) {\n>> + if (++found > 1) {\n>> + next = NULL;\n>> + break;\n>> + }\n>> + if (!child->addr && int128_ge(mr->size, child->size)) {\n> \n> \n> Ah, I tried this one but in v4's 18/18 (that hinting thing), did not work\n> out but for a different reason.\n\nYeah, I did take some inspiration from your code, but we were thinking\nof different scenarios (I wanted to cover the child->enabled == true).\n\nPaolo\n\n> \n>> + /* A child is included in its entirety. If it's the only\n>> + * enabled one, use it in the hope of finding an alias down the\n>> + * way. This will also let us share FlatViews.\n>> + */\n>> + next = child;\n>> + }\n>> + }\n>> + }\n>> + if (next) {\n>> + mr = next;\n>> + continue;\n>> + }\n>> + }\n>> +\n>> + break;\n>> }\n>> \n>> return mr;\n>>\n> \n>","headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=)","ext-mx03.extmail.prod.ext.phx2.redhat.com;\n\tdmarc=none (p=none dis=none) header.from=redhat.com","ext-mx03.extmail.prod.ext.phx2.redhat.com;\n\tspf=fail smtp.mailfrom=pbonzini@redhat.com"],"Received":["from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11])\n\t(using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xydVH6kZBz9t3v\n\tfor ;\n\tThu, 21 Sep 2017 23:57:59 +1000 (AEST)","from localhost ([::1]:53878 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t)\n\tid 1dv1zJ-0003Vy-VZ\n\tfor incoming@patchwork.ozlabs.org; Thu, 21 Sep 2017 09:57:58 -0400","from eggs.gnu.org ([2001:4830:134:3::10]:39210)\n\tby lists.gnu.org with esmtp (Exim 4.71)\n\t(envelope-from ) id 1dv1ym-0003UB-UK\n\tfor qemu-devel@nongnu.org; Thu, 21 Sep 2017 09:57:26 -0400","from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)\n\t(envelope-from ) id 1dv1yi-0002bt-1c\n\tfor qemu-devel@nongnu.org; Thu, 21 Sep 2017 09:57:24 -0400","from mx1.redhat.com ([209.132.183.28]:54372)\n\tby eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32)\n\t(Exim 4.71) (envelope-from ) id 1dv1yh-0002bZ-QR\n\tfor qemu-devel@nongnu.org; Thu, 21 Sep 2017 09:57:19 -0400","from smtp.corp.redhat.com\n\t(int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13])\n\t(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby mx1.redhat.com (Postfix) with ESMTPS id AA6EC7DCC2;\n\tThu, 21 Sep 2017 13:57:18 +0000 (UTC)","from [10.36.117.52] (ovpn-117-52.ams2.redhat.com [10.36.117.52])\n\tby smtp.corp.redhat.com (Postfix) with ESMTPS id E8BA8614D9;\n\tThu, 21 Sep 2017 13:57:16 +0000 (UTC)"],"DMARC-Filter":"OpenDMARC Filter v1.3.2 mx1.redhat.com AA6EC7DCC2","To":"Alexey Kardashevskiy , qemu-devel@nongnu.org","References":"<20170921120751.3027-1-pbonzini@redhat.com>\n\t<20170921120751.3027-3-pbonzini@redhat.com>\n\t<1d5f2bb4-c330-98b9-bf1a-6024a9f9093d@ozlabs.ru>","From":"Paolo Bonzini ","Message-ID":"","Date":"Thu, 21 Sep 2017 15:57:15 +0200","User-Agent":"Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101\n\tThunderbird/52.3.0","MIME-Version":"1.0","In-Reply-To":"<1d5f2bb4-c330-98b9-bf1a-6024a9f9093d@ozlabs.ru>","Content-Type":"text/plain; charset=utf-8","Content-Language":"en-US","Content-Transfer-Encoding":"7bit","X-Scanned-By":"MIMEDefang 2.79 on 10.5.11.13","X-Greylist":"Sender IP whitelisted, not delayed by milter-greylist-4.5.16\n\t(mx1.redhat.com [10.5.110.27]);\n\tThu, 21 Sep 2017 13:57:18 +0000 (UTC)","X-detected-operating-system":"by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic]\n\t[fuzzy]","X-Received-From":"209.132.183.28","Subject":"Re: [Qemu-devel] [PATCH 2/3] memory: seek FlatView sharing\n\tcandidates among children subregions","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.21","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"\"Qemu-devel\"\n\t"}},{"id":1773257,"web_url":"http://patchwork.ozlabs.org/comment/1773257/","msgid":"","list_archive_url":null,"date":"2017-09-22T04:45:50","subject":"Re: [Qemu-devel] [PATCH 2/3] memory: seek FlatView sharing\n\tcandidates among children subregions","submitter":{"id":7621,"url":"http://patchwork.ozlabs.org/api/people/7621/","name":"Alexey Kardashevskiy","email":"aik@ozlabs.ru"},"content":"On 21/09/17 23:57, Paolo Bonzini wrote:\n> On 21/09/2017 15:39, Alexey Kardashevskiy wrote:\n>> On 21/09/17 22:07, Paolo Bonzini wrote:\n>>> A container can be used instead of an alias to allow switching between\n>>> multiple subregions. In this case we cannot directly share the\n>>> subregions (since they only belong to a single parent), but if the\n>>> subregions are aliases we can in turn walk those.\n>>>\n>>> While this does not reduce much the number of FlatViews that are created,\n>>> it makes it possible to share the PCI bus master FlatViews and their\n>>> AddressSpaceDispatch structures. For 112 virtio-net-pci devices, boot time\n>>> is reduced from 25 to 10 seconds and memory consumption from 1.4 to 1 G.\n>>>\n>>> Signed-off-by: Paolo Bonzini \n>>> ---\n>>> memory.c | 41 +++++++++++++++++++++++++++++++++++------\n>>> 1 file changed, 35 insertions(+), 6 deletions(-)\n>>>\n>>> diff --git a/memory.c b/memory.c\n>>> index 4952cc5d84..3207ae55e2 100644\n>>> --- a/memory.c\n>>> +++ b/memory.c\n>>> @@ -733,12 +733,41 @@ static void render_memory_region(FlatView *view,\n>>> \n>>> static MemoryRegion *memory_region_get_flatview_root(MemoryRegion *mr)\n>>> {\n>>> - while (mr->alias && !mr->alias_offset &&\n>>> - int128_ge(mr->size, mr->alias->size)) {\n>>> - /* The alias is included in its entirety. Use it as\n>>> - * the \"real\" root, so that we can share more FlatViews.\n>>> - */\n>>> - mr = mr->alias;\n>>> + while (mr->enabled) {\n>>> + if (mr->alias && !mr->alias_offset &&\n>>> + int128_ge(mr->size, mr->alias->size)) {\n>>> + /* The alias is included in its entirety. Use it as\n>>> + * the \"real\" root, so that we can share more FlatViews.\n>>> + */\n>>> + mr = mr->alias;\n>>> + continue;\n>>> + }\n>>> +\n>>> + if (!mr->terminates) {\n>>\n>> Can an MR have terminates==true and children by the same time? If so, what for?\n> \n> Yes, children override the parent. > But more important, !mr->terminates\n> means that patch 3 doesn't think that MR produces an empty FlatView.\n\n\nI see, after some debugging only MRs with @terminates==true appear in the\ndispatch tree which makes sense. But I am still struggling to understand\nwhat @terminates really means here in plain english.","headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=)","ozlabs.org;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=ozlabs-ru.20150623.gappssmtp.com\n\theader.i=@ozlabs-ru.20150623.gappssmtp.com\n\theader.b=\"iKoCaHtU\"; dkim-atps=neutral"],"Received":["from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11])\n\t(using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xz1Cb2P2dz9sNr\n\tfor ;\n\tFri, 22 Sep 2017 14:46:30 +1000 (AEST)","from localhost ([::1]:56662 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t)\n\tid 1dvFrA-0006Ta-8Z\n\tfor incoming@patchwork.ozlabs.org; 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\n\tThu, 21 Sep 2017 21:45:54 -0700 (PDT)","To":"Paolo Bonzini , qemu-devel@nongnu.org","References":"<20170921120751.3027-1-pbonzini@redhat.com>\n\t<20170921120751.3027-3-pbonzini@redhat.com>\n\t<1d5f2bb4-c330-98b9-bf1a-6024a9f9093d@ozlabs.ru>\n\t","From":"Alexey Kardashevskiy ","Message-ID":"","Date":"Fri, 22 Sep 2017 14:45:50 +1000","User-Agent":"Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101\n\tThunderbird/52.2.1","MIME-Version":"1.0","In-Reply-To":"","Content-Type":"text/plain; charset=utf-8","Content-Language":"en-AU","Content-Transfer-Encoding":"7bit","X-detected-operating-system":"by eggs.gnu.org: Genre and OS details not\n\trecognized.","X-Received-From":"2607:f8b0:400e:c05::242","Subject":"Re: [Qemu-devel] [PATCH 2/3] memory: seek FlatView sharing\n\tcandidates among children subregions","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.21","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"\"Qemu-devel\"\n\t"}},{"id":1773320,"web_url":"http://patchwork.ozlabs.org/comment/1773320/","msgid":"","list_archive_url":null,"date":"2017-09-22T07:28:25","subject":"Re: [Qemu-devel] [PATCH 2/3] memory: seek FlatView sharing\n\tcandidates among children subregions","submitter":{"id":2701,"url":"http://patchwork.ozlabs.org/api/people/2701/","name":"Paolo Bonzini","email":"pbonzini@redhat.com"},"content":"On 22/09/2017 06:45, Alexey Kardashevskiy wrote:\n> On 21/09/17 23:57, Paolo Bonzini wrote:\n>> On 21/09/2017 15:39, Alexey Kardashevskiy wrote:\n>>> On 21/09/17 22:07, Paolo Bonzini wrote:\n>>>> A container can be used instead of an alias to allow switching between\n>>>> multiple subregions. In this case we cannot directly share the\n>>>> subregions (since they only belong to a single parent), but if the\n>>>> subregions are aliases we can in turn walk those.\n>>>>\n>>>> While this does not reduce much the number of FlatViews that are created,\n>>>> it makes it possible to share the PCI bus master FlatViews and their\n>>>> AddressSpaceDispatch structures. For 112 virtio-net-pci devices, boot time\n>>>> is reduced from 25 to 10 seconds and memory consumption from 1.4 to 1 G.\n>>>>\n>>>> Signed-off-by: Paolo Bonzini \n>>>> ---\n>>>> memory.c | 41 +++++++++++++++++++++++++++++++++++------\n>>>> 1 file changed, 35 insertions(+), 6 deletions(-)\n>>>>\n>>>> diff --git a/memory.c b/memory.c\n>>>> index 4952cc5d84..3207ae55e2 100644\n>>>> --- a/memory.c\n>>>> +++ b/memory.c\n>>>> @@ -733,12 +733,41 @@ static void render_memory_region(FlatView *view,\n>>>> \n>>>> static MemoryRegion *memory_region_get_flatview_root(MemoryRegion *mr)\n>>>> {\n>>>> - while (mr->alias && !mr->alias_offset &&\n>>>> - int128_ge(mr->size, mr->alias->size)) {\n>>>> - /* The alias is included in its entirety. Use it as\n>>>> - * the \"real\" root, so that we can share more FlatViews.\n>>>> - */\n>>>> - mr = mr->alias;\n>>>> + while (mr->enabled) {\n>>>> + if (mr->alias && !mr->alias_offset &&\n>>>> + int128_ge(mr->size, mr->alias->size)) {\n>>>> + /* The alias is included in its entirety. Use it as\n>>>> + * the \"real\" root, so that we can share more FlatViews.\n>>>> + */\n>>>> + mr = mr->alias;\n>>>> + continue;\n>>>> + }\n>>>> +\n>>>> + if (!mr->terminates) {\n>>>\n>>> Can an MR have terminates==true and children by the same time? If so, what for?\n>>\n>> Yes, children override the parent. > But more important, !mr->terminates\n>> means that patch 3 doesn't think that MR produces an empty FlatView.\n> \n> \n> I see, after some debugging only MRs with @terminates==true appear in the\n> dispatch tree which makes sense. But I am still struggling to understand\n> what @terminates really means here in plain english.\n\nAs you found out, perhaps \"dispatched\" would be a better name than\n\"terminates\". A MR can be \"alias\", \"terminates\" or \"!terminates\".\nAliases are resolved early. If a range is allocated to a \"terminates\"\nregion A (and not to any other \"terminates\" region in A's subtree), it\ndispatches to A.\n\nIf a range is allocated to a \"!terminates\" region B (and to any other\n\"terminates\" region in B's subtree, QEMU doesn't add it to the FlatView\nand it will be dispatched to another memory region: B's parent, another\nregion in B's parent's subtree, B's grandparent, another region in B's\ngrandparent's subtree, and so on---if nobody accepts it, it goes to\nunassigned_mem_ops.\n\nPaolo","headers":{"Return-Path":"","X-Original-To":"incoming@patchwork.ozlabs.org","Delivered-To":"patchwork-incoming@bilbo.ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=pass (mailfrom) smtp.mailfrom=nongnu.org\n\t(client-ip=2001:4830:134:3::11; helo=lists.gnu.org;\n\tenvelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org;\n\treceiver=)","ext-mx06.extmail.prod.ext.phx2.redhat.com;\n\tdmarc=none (p=none dis=none) header.from=redhat.com","ext-mx06.extmail.prod.ext.phx2.redhat.com;\n\tspf=fail smtp.mailfrom=pbonzini@redhat.com"],"Received":["from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11])\n\t(using TLSv1 with cipher AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby ozlabs.org (Postfix) with ESMTPS id 3xz4qk3Vsnz9sNc\n\tfor ;\n\tFri, 22 Sep 2017 17:29:38 +1000 (AEST)","from localhost ([::1]:57069 helo=lists.gnu.org)\n\tby lists.gnu.org with esmtp (Exim 4.71) (envelope-from\n\t)\n\tid 1dvIP2-0000UW-KI\n\tfor incoming@patchwork.ozlabs.org; Fri, 22 Sep 2017 03:29:36 -0400","from eggs.gnu.org ([2001:4830:134:3::10]:60730)\n\tby lists.gnu.org with esmtp (Exim 4.71)\n\t(envelope-from ) id 1dvINz-0008WI-Te\n\tfor qemu-devel@nongnu.org; Fri, 22 Sep 2017 03:28:33 -0400","from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)\n\t(envelope-from ) id 1dvINw-0005Zp-Ko\n\tfor qemu-devel@nongnu.org; Fri, 22 Sep 2017 03:28:31 -0400","from mx1.redhat.com ([209.132.183.28]:48464)\n\tby eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32)\n\t(Exim 4.71) (envelope-from ) id 1dvINw-0005Zf-BF\n\tfor qemu-devel@nongnu.org; Fri, 22 Sep 2017 03:28:28 -0400","from smtp.corp.redhat.com\n\t(int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16])\n\t(using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits))\n\t(No client certificate requested)\n\tby mx1.redhat.com (Postfix) with ESMTPS id 6AF43267C4;\n\tFri, 22 Sep 2017 07:28:27 +0000 (UTC)","from [10.36.117.77] (ovpn-117-77.ams2.redhat.com [10.36.117.77])\n\tby smtp.corp.redhat.com (Postfix) with ESMTPS id BFB2E5C549;\n\tFri, 22 Sep 2017 07:28:26 +0000 (UTC)"],"DMARC-Filter":"OpenDMARC Filter v1.3.2 mx1.redhat.com 6AF43267C4","To":"Alexey Kardashevskiy , qemu-devel@nongnu.org","References":"<20170921120751.3027-1-pbonzini@redhat.com>\n\t<20170921120751.3027-3-pbonzini@redhat.com>\n\t<1d5f2bb4-c330-98b9-bf1a-6024a9f9093d@ozlabs.ru>\n\t\n\t","From":"Paolo Bonzini ","Message-ID":"","Date":"Fri, 22 Sep 2017 09:28:25 +0200","User-Agent":"Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101\n\tThunderbird/52.3.0","MIME-Version":"1.0","In-Reply-To":"","Content-Type":"text/plain; charset=utf-8","Content-Language":"en-US","Content-Transfer-Encoding":"7bit","X-Scanned-By":"MIMEDefang 2.79 on 10.5.11.16","X-Greylist":"Sender IP whitelisted, not delayed by milter-greylist-4.5.16\n\t(mx1.redhat.com [10.5.110.30]);\n\tFri, 22 Sep 2017 07:28:27 +0000 (UTC)","X-detected-operating-system":"by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic]\n\t[fuzzy]","X-Received-From":"209.132.183.28","Subject":"Re: [Qemu-devel] [PATCH 2/3] memory: seek FlatView sharing\n\tcandidates among children subregions","X-BeenThere":"qemu-devel@nongnu.org","X-Mailman-Version":"2.1.21","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"\"Qemu-devel\"\n\t"}}]