From: Pankaj Gupta <pagupta-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> To: Igor Mammedov <imammedo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Cc: kwolf-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, lcapitulino-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, jack-AlSwsSmVLrQ@public.gmane.org, xiaoguangrong eric <xiaoguangrong.eric-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, riel-ebMLmSuQjDVBDgjK7y7TUQ@public.gmane.org, linux-nvdimm-y27Ovi1pjclAfugRpC6u6w@public.gmane.org, david-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, ross zwisler <ross.zwisler-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, qemu-devel-qX2TKyscuCcdnm+yROfE0A@public.gmane.org, hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, mst-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, stefanha-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, niteshnarayanlal-PkbjNfxxIARBDgjK7y7TUQ@public.gmane.org, marcel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, pbonzini-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, nilal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org Subject: Re: [Qemu-devel] [RFC v2 0/2] kvm "fake DAX" device flushing Date: Mon, 4 Jun 2018 01:56:55 -0400 (EDT) [thread overview] Message-ID: <1227242806.39629768.1528091815515.JavaMail.zimbra@redhat.com> (raw) In-Reply-To: <20180601142410.5c986f13-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Hi Igor, > > [...] > > - Qemu virtio-pmem device > > It exposes a persistent memory range to KVM guest which > > at host side is file backed memory and works as persistent > > memory device. In addition to this it provides virtio > > device handling of flushing interface. KVM guest performs > > Qemu side asynchronous sync using this interface. > a random high level question, > Have you considered using a separate (from memory itself) > virtio device as controller for exposing some memory, async flushing. > And then just slaving pc-dimm devices to it with notification/ACPI > code suppressed so that guest won't touch them? No. > > That way it might be more scale-able, you consume only 1 PCI slot > for controller vs multiple for virtio-pmem devices. That sounds like a good suggestion. I will note it as an enhancement once we have other concerns related to basic working of 'flush' interface addressed. Then probably we can work on things 'need to optimize' with robust core flush functionality. BTW any sample code doing this right now in Qemu? > > > > Changes from previous RFC[1]: > > > > - Reuse existing 'pmem' code for registering persistent > > memory and other operations instead of creating an entirely > > new block driver. > > - Use VIRTIO driver to register memory information with > > nvdimm_bus and create region_type accordingly. > > - Call VIRTIO flush from existing pmem driver. > > > > Details of project idea for 'fake DAX' flushing interface is > > shared [2] & [3]. > > > > Pankaj Gupta (2): > > Add virtio-pmem guest driver > > pmem: device flush over VIRTIO > > > > [1] https://marc.info/?l=linux-mm&m=150782346802290&w=2 > > [2] https://www.spinics.net/lists/kvm/msg149761.html > > [3] https://www.spinics.net/lists/kvm/msg153095.html > > > > drivers/nvdimm/region_devs.c | 7 ++ > > drivers/virtio/Kconfig | 12 +++ > > drivers/virtio/Makefile | 1 > > drivers/virtio/virtio_pmem.c | 118 > > +++++++++++++++++++++++++++++++++++++++ > > include/linux/libnvdimm.h | 4 + > > include/uapi/linux/virtio_ids.h | 1 > > include/uapi/linux/virtio_pmem.h | 58 +++++++++++++++++++ > > 7 files changed, 201 insertions(+) > > > > >
WARNING: multiple messages have this Message-ID (diff)
From: Pankaj Gupta <pagupta@redhat.com> To: Igor Mammedov <imammedo@redhat.com> Cc: kwolf@redhat.com, haozhong zhang <haozhong.zhang@intel.com>, nilal@redhat.com, jack@suse.cz, xiaoguangrong eric <xiaoguangrong.eric@gmail.com>, kvm@vger.kernel.org, riel@surriel.com, linux-nvdimm@ml01.01.org, david@redhat.com, ross zwisler <ross.zwisler@intel.com>, linux-kernel@vger.kernel.org, qemu-devel@nongnu.org, hch@infradead.org, linux-mm@kvack.org, mst@redhat.com, stefanha@redhat.com, niteshnarayanlal@hotmail.com, marcel@redhat.com, pbonzini@redhat.com, dan j williams <dan.j.williams@intel.com>, lcapitulino@redhat.com Subject: Re: [Qemu-devel] [RFC v2 0/2] kvm "fake DAX" device flushing Date: Mon, 4 Jun 2018 01:56:55 -0400 (EDT) [thread overview] Message-ID: <1227242806.39629768.1528091815515.JavaMail.zimbra@redhat.com> (raw) In-Reply-To: <20180601142410.5c986f13@redhat.com> Hi Igor, > > [...] > > - Qemu virtio-pmem device > > It exposes a persistent memory range to KVM guest which > > at host side is file backed memory and works as persistent > > memory device. In addition to this it provides virtio > > device handling of flushing interface. KVM guest performs > > Qemu side asynchronous sync using this interface. > a random high level question, > Have you considered using a separate (from memory itself) > virtio device as controller for exposing some memory, async flushing. > And then just slaving pc-dimm devices to it with notification/ACPI > code suppressed so that guest won't touch them? No. > > That way it might be more scale-able, you consume only 1 PCI slot > for controller vs multiple for virtio-pmem devices. That sounds like a good suggestion. I will note it as an enhancement once we have other concerns related to basic working of 'flush' interface addressed. Then probably we can work on things 'need to optimize' with robust core flush functionality. BTW any sample code doing this right now in Qemu? > > > > Changes from previous RFC[1]: > > > > - Reuse existing 'pmem' code for registering persistent > > memory and other operations instead of creating an entirely > > new block driver. > > - Use VIRTIO driver to register memory information with > > nvdimm_bus and create region_type accordingly. > > - Call VIRTIO flush from existing pmem driver. > > > > Details of project idea for 'fake DAX' flushing interface is > > shared [2] & [3]. > > > > Pankaj Gupta (2): > > Add virtio-pmem guest driver > > pmem: device flush over VIRTIO > > > > [1] https://marc.info/?l=linux-mm&m=150782346802290&w=2 > > [2] https://www.spinics.net/lists/kvm/msg149761.html > > [3] https://www.spinics.net/lists/kvm/msg153095.html > > > > drivers/nvdimm/region_devs.c | 7 ++ > > drivers/virtio/Kconfig | 12 +++ > > drivers/virtio/Makefile | 1 > > drivers/virtio/virtio_pmem.c | 118 > > +++++++++++++++++++++++++++++++++++++++ > > include/linux/libnvdimm.h | 4 + > > include/uapi/linux/virtio_ids.h | 1 > > include/uapi/linux/virtio_pmem.h | 58 +++++++++++++++++++ > > 7 files changed, 201 insertions(+) > > > > >
next prev parent reply other threads:[~2018-06-04 5:56 UTC|newest] Thread overview: 80+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-04-25 11:24 [RFC v2 0/2] kvm "fake DAX" device flushing Pankaj Gupta 2018-04-25 11:24 ` [Qemu-devel] " Pankaj Gupta 2018-04-25 11:24 ` Pankaj Gupta [not found] ` <20180425112415.12327-1-pagupta-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2018-04-25 11:24 ` [RFC v2 1/2] virtio: add pmem driver Pankaj Gupta 2018-04-25 11:24 ` [Qemu-devel] " Pankaj Gupta 2018-04-25 11:24 ` Pankaj Gupta [not found] ` <20180425112415.12327-2-pagupta-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2018-04-25 14:21 ` Dan Williams 2018-04-25 14:21 ` [Qemu-devel] " Dan Williams 2018-04-25 14:21 ` Dan Williams [not found] ` <CAPcyv4hvrB08XPTbVK0xT2_1Xmaid=-v3OMxJVDTNwQucsOHLA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2018-04-25 14:43 ` Dan Williams 2018-04-25 14:43 ` [Qemu-devel] " Dan Williams 2018-04-25 14:43 ` Dan Williams [not found] ` <CAPcyv4hiowWozV527sQA_e4fdgCYbD6xfG==vepAqu0hxQEQcw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2018-04-26 12:27 ` Jeff Moyer 2018-04-26 12:27 ` [Qemu-devel] " Jeff Moyer 2018-04-26 12:27 ` Jeff Moyer 2018-04-26 12:27 ` Jeff Moyer [not found] ` <x49o9i6885e.fsf-RRHT56Q3PSP4kTEheFKJxxDDeQx5vsVwAInAS/Ez/D0@public.gmane.org> 2018-04-26 17:15 ` [Qemu-devel] " Pankaj Gupta 2018-04-26 17:15 ` Pankaj Gupta [not found] ` <1499190564.23017177.1524762938762.JavaMail.zimbra-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2018-04-26 17:24 ` Jeff Moyer 2018-04-26 17:24 ` Jeff Moyer 2018-04-25 14:52 ` Michael S. Tsirkin 2018-04-25 14:52 ` [Qemu-devel] " Michael S. Tsirkin 2018-04-25 14:52 ` Michael S. Tsirkin [not found] ` <20180425174705-mutt-send-email-mst-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> 2018-04-25 15:11 ` [Qemu-devel] " Pankaj Gupta 2018-04-25 15:11 ` Pankaj Gupta 2018-04-26 13:12 ` Stefan Hajnoczi [not found] ` <20180426131236.GA30991-lxVrvc10SDRcolVlb+j0YCZi+YwRKgec@public.gmane.org> 2018-04-26 15:44 ` Pankaj Gupta 2018-04-26 15:44 ` Pankaj Gupta 2018-04-27 13:31 ` Stefan Hajnoczi [not found] ` <20180427133146.GB11150-lxVrvc10SDRcolVlb+j0YCZi+YwRKgec@public.gmane.org> 2018-04-28 10:48 ` Pankaj Gupta 2018-04-28 10:48 ` Pankaj Gupta 2018-04-25 11:24 ` [RFC v2 2/2] pmem: device flush over VIRTIO Pankaj Gupta 2018-04-25 11:24 ` [Qemu-devel] " Pankaj Gupta 2018-04-25 11:24 ` Pankaj Gupta [not found] ` <20180425112415.12327-3-pagupta-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2018-04-25 14:23 ` Dan Williams 2018-04-25 14:23 ` [Qemu-devel] " Dan Williams 2018-04-25 14:23 ` Dan Williams [not found] ` <CAPcyv4gpZzKfE7jY1peYOVd6sVhNz7jce1s_xNH_2Lt8AjRK-Q-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2018-04-25 14:47 ` Pankaj Gupta 2018-04-25 14:47 ` [Qemu-devel] " Pankaj Gupta 2018-04-25 14:47 ` Pankaj Gupta 2018-04-26 13:15 ` Stefan Hajnoczi 2018-04-26 13:15 ` [Qemu-devel] " Stefan Hajnoczi [not found] ` <20180426131517.GB30991-lxVrvc10SDRcolVlb+j0YCZi+YwRKgec@public.gmane.org> 2018-04-26 16:40 ` Pankaj Gupta 2018-04-26 16:40 ` [Qemu-devel] " Pankaj Gupta 2018-04-26 16:40 ` Pankaj Gupta [not found] ` <58645254.23011245.1524760853269.JavaMail.zimbra-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2018-04-26 16:57 ` Dan Williams 2018-04-26 16:57 ` [Qemu-devel] " Dan Williams 2018-04-26 16:57 ` Dan Williams [not found] ` <CAPcyv4jv-hJNKJxak98T7aCnWztVEDTE8o=8fjvOrVmrTfyjdA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org> 2018-04-26 17:13 ` Pankaj Gupta 2018-04-26 17:13 ` [Qemu-devel] " Pankaj Gupta 2018-04-26 17:13 ` Pankaj Gupta 2018-04-25 11:24 ` [RFC v2] qemu: Add virtio pmem device Pankaj Gupta 2018-04-25 11:24 ` [Qemu-devel] " Pankaj Gupta 2018-04-25 11:24 ` Pankaj Gupta [not found] ` <20180425112415.12327-4-pagupta-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2018-04-25 11:35 ` [Qemu-devel] " no-reply-isE1Te71pDtAfugRpC6u6w 2018-04-25 11:35 ` no-reply 2018-04-25 11:35 ` no-reply 2018-04-25 11:58 ` Pankaj Gupta 2018-04-25 11:58 ` Pankaj Gupta 2018-04-25 14:23 ` Eric Blake 2018-04-25 14:23 ` Eric Blake [not found] ` <79f72139-0fcb-3d5e-a16c-24f3b5ee1a07-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2018-04-25 14:51 ` Pankaj Gupta 2018-04-25 14:51 ` Pankaj Gupta 2018-04-25 11:46 ` no-reply 2018-04-25 11:46 ` no-reply 2018-04-25 11:46 ` no-reply 2018-04-25 14:25 ` Eric Blake 2018-04-25 14:25 ` Eric Blake [not found] ` <25f3e433-cfa6-4a62-ba7f-47aef1119dfc-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2018-04-25 14:55 ` Pankaj Gupta 2018-04-25 14:55 ` Pankaj Gupta 2018-04-26 13:24 ` Stefan Hajnoczi 2018-04-26 13:24 ` [Qemu-devel] " Stefan Hajnoczi [not found] ` <20180426132406.GC30991-lxVrvc10SDRcolVlb+j0YCZi+YwRKgec@public.gmane.org> 2018-04-26 16:43 ` Pankaj Gupta 2018-04-26 16:43 ` Pankaj Gupta 2018-06-01 12:24 ` [Qemu-devel] [RFC v2 0/2] kvm "fake DAX" device flushing Igor Mammedov 2018-06-01 12:24 ` Igor Mammedov [not found] ` <20180601142410.5c986f13-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> 2018-06-04 5:56 ` Pankaj Gupta [this message] 2018-06-04 5:56 ` Pankaj Gupta 2018-06-04 9:55 ` David Hildenbrand 2018-06-04 9:55 ` David Hildenbrand
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=1227242806.39629768.1528091815515.JavaMail.zimbra@redhat.com \ --to=pagupta-h+wxahxf7alqt0dzr+alfa@public.gmane.org \ --cc=david-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \ --cc=hch-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org \ --cc=imammedo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \ --cc=jack-AlSwsSmVLrQ@public.gmane.org \ --cc=kvm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \ --cc=kwolf-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \ --cc=lcapitulino-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \ --cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \ --cc=linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org \ --cc=linux-nvdimm-y27Ovi1pjclAfugRpC6u6w@public.gmane.org \ --cc=marcel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \ --cc=mst-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \ --cc=nilal-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \ --cc=niteshnarayanlal-PkbjNfxxIARBDgjK7y7TUQ@public.gmane.org \ --cc=pbonzini-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \ --cc=qemu-devel-qX2TKyscuCcdnm+yROfE0A@public.gmane.org \ --cc=riel-ebMLmSuQjDVBDgjK7y7TUQ@public.gmane.org \ --cc=ross.zwisler-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org \ --cc=stefanha-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org \ --cc=xiaoguangrong.eric-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.