From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38485) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fSi4e-00067N-7Z for qemu-devel@nongnu.org; Tue, 12 Jun 2018 08:06:58 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fSi4a-000613-6C for qemu-devel@nongnu.org; Tue, 12 Jun 2018 08:06:56 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:52042 helo=mx1.redhat.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1fSi4Z-00060c-W2 for qemu-devel@nongnu.org; Tue, 12 Jun 2018 08:06:52 -0400 Date: Tue, 12 Jun 2018 14:06:43 +0200 From: Igor Mammedov Message-ID: <20180612140643.6f6ed34d@redhat.com> In-Reply-To: <1527840629-18648-1-git-send-email-junyan.he@gmx.com> References: <1527840629-18648-1-git-send-email-junyan.he@gmx.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH V6 0/7] nvdimm: guarantee persistence of QEMU writes to persistent memory List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: junyan.he@gmx.com Cc: qemu-devel@nongnu.org, Haozhong Zhang , xiaoguangrong.eric@gmail.com, crosthwaite.peter@gmail.com, mst@redhat.com, dgilbert@redhat.com, ehabkost@redhat.com, quintela@redhat.com, Junyan He , stefanha@redhat.com, pbonzini@redhat.com, rth@twiddle.net On Fri, 1 Jun 2018 16:10:22 +0800 junyan.he@gmx.com wrote: > From: Junyan He > > QEMU writes to vNVDIMM backends in the vNVDIMM label emulation and > live migration. If the backend is on the persistent memory, QEMU needs > to take proper operations to ensure its writes persistent on the > persistent memory. Otherwise, a host power failure may result in the > loss the guest data on the persistent memory. extra question, what are expected behavior when QEMU is built without libpmem and user specifies pmem=on for backend? > > This v3 patch series is based on Marcel's patch "mem: add share > parameter to memory-backend-ram" [1] because of the changes in patch 1. > > [1] https://lists.gnu.org/archive/html/qemu-devel/2018-02/msg03858.html > > Previous versions can be found at > v5: https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg02258.html > V4: https://lists.gnu.org/archive/html/qemu-devel/2018-02/msg06993.html > v3: https://lists.gnu.org/archive/html/qemu-devel/2018-02/msg04365.html > v2: https://lists.gnu.org/archive/html/qemu-devel/2018-02/msg01579.html > v1: https://lists.gnu.org/archive/html/qemu-devel/2017-12/msg05040.html > > Changes in v6: > * (Patch 1) Expose all ram block flags rather than redefine the flags. > * (Patch 4) Use pkg-config rather the hard check when configure. > * (Patch 7) Sync and flush all the pmem data when migration completes, > rather than sync pages one by one in previous version. > > Changes in v5: > * (Patch 9) Add post copy check and output some messages for nvdimm. > > Changes in v4: > * (Patch 2) Fix compilation errors found by patchew. > > Changes in v3: > * (Patch 5) Add a is_pmem flag to ram_handle_compressed() and handle > PMEM writes in it, so we don't need the _common function. > * (Patch 6) Expose qemu_get_buffer_common so we can remove the > unnecessary qemu_get_buffer_to_pmem wrapper. > * (Patch 8) Add a is_pmem flag to xbzrle_decode_buffer() and handle > PMEM writes in it, so we can remove the unnecessary > xbzrle_decode_buffer_{common, to_pmem}. > * Move libpmem stubs to stubs/pmem.c and fix the compilation failures > of test-{xbzrle,vmstate}.c. > > Changes in v2: > * (Patch 1) Use a flags parameter in file ram allocation functions. > * (Patch 2) Add a new option 'pmem' to hostmem-file. > * (Patch 3) Use libpmem to operate on the persistent memory, rather > than re-implementing those operations in QEMU. > * (Patch 5-8) Consider the write persistence in the migration path. > > > Junyan: > [1/7] memory, exec: Expose all memory block related flags. > [6/7] migration/ram: Add check and info message to nvdimm post copy. > [7/7] migration/ram: ensure write persistence on loading all date to PMEM. > > Haozhong: > [5/7] mem/nvdimm: ensure write persistence to PMEM in label emulation > > Haozhong & Junyan: > [2/7] memory, exec: switch file ram allocation functions to 'flags' parameters > [3/7] hostmem-file: add the 'pmem' option > [4/7] configure: add libpmem support > > > Signed-off-by: Haozhong Zhang > Signed-off-by: Junyan He > > --- > backends/hostmem-file.c | 28 +++++++++++++++++++++++++++- > configure | 29 +++++++++++++++++++++++++++++ > docs/nvdimm.txt | 14 ++++++++++++++ > exec.c | 36 ++++++++++++++---------------------- > hw/mem/nvdimm.c | 9 ++++++++- > include/exec/memory.h | 31 +++++++++++++++++++++++++++++-- > include/exec/ram_addr.h | 28 ++++++++++++++++++++++++++-- > include/qemu/pmem.h | 24 ++++++++++++++++++++++++ > memory.c | 8 +++++--- > migration/ram.c | 18 ++++++++++++++++++ > numa.c | 2 +- > qemu-options.hx | 7 +++++++ > stubs/Makefile.objs | 1 + > stubs/pmem.c | 23 +++++++++++++++++++++++ > 14 files changed, 226 insertions(+), 32 deletions(-)