[Qemu-devel] [PATCH V6 00/11] Add support for binding guest numa nodes to host numa nodes

[Wanlong Gao]

As you know, QEMU can't direct it's memory allocation now, this may cause
guest cross node access performance regression.
And, the worse thing is that if PCI-passthrough is used,
direct-attached-device uses DMA transfer between device and qemu process.
All pages of the guest will be pinned by get_user_pages().

KVM_ASSIGN_PCI_DEVICE ioctl
  kvm_vm_ioctl_assign_device()
    =>kvm_assign_device()
      => kvm_iommu_map_memslots()
        => kvm_iommu_map_pages()
           => kvm_pin_pages()

So, with direct-attached-device, all guest page's page count will be +1 and
any page migration will not work. AutoNUMA won't too.

So, we should set the guest nodes memory allocation policy before
the pages are really mapped.

According to this patch set, we are able to set guest nodes memory policy
like following:

 -numa node,nodeid=0,cpus=0, \
 -numa mem,size=1024M,policy=membind,host-nodes=0-1 \
 -numa node,nodeid=1,cpus=1 \
 -numa mem,size=1024M,policy=interleave,host-nodes=1

This supports 
"policy={default|membind|interleave|preferred},relative=true,host-nodes=N-N" 
like format.


Also add "set-mem-policy" QMP and hmp command to set memory policy.

And patch 10/11 adds a QMP command "query-numa" to show numa info through
this API.

And patch 11/11 converts the "info numa" monitor command to use this
QMP command "query-numa".


V1->V2:
    change to use QemuOpts in numa options (Paolo)
    handle Error in mpol parser (Paolo)
    change qmp command format to mem-policy=membind,mem-hostnode=0-1 like 
(Paolo)
V2->V3:
    also handle Error in cpus parser (5/10)
    split out common parser from cpus and hostnode parser (Bandan 6/10)
V3-V4:
    rebase to request for comments
V4->V5:
    use OptVisitor and split -numa option (Paolo)
     - s/set-mpol/set-mem-policy (Andreas)
     - s/mem-policy/policy
     - s/mem-hostnode/host-nodes
    fix hmp command process after error (Luiz)
    add qmp command query-numa and convert info numa to it (Luiz)
V5->V6:
    remove tabs in json file (Laszlo, Paolo)
    add back "-numa node,mem=xxx" as legacy (Paolo)
    change cpus and host-nodes to array (Laszlo, Eric)
    change "nodeid" to "uint16"
    add NumaMemPolicy enum type (Eric)
    rebased on Laszlo's "OptsVisitor: support / flatten integer ranges for 
repeating options" patch set, thanks for Laszlo's help


Wanlong Gao (11):
  NUMA: add NumaOptions, NumaNodeOptions and NumaMemOptions
  NUMA: split -numa option
  NUMA: move numa related code to numa.c
  NUMA: Add numa_info structure to contain numa nodes info
  NUMA: Add Linux libnuma detection
  NUMA: parse guest numa nodes memory policy
  NUMA: set guest numa nodes memory policy
  NUMA: add qmp command set-mem-policy to set memory policy for NUMA
    node
  NUMA: add hmp command set-mem-policy
  NUMA: add qmp command query-numa
  NUMA: convert hmp command info_numa to use qmp command query_numa

 Makefile.target         |   2 +-
 configure               |  32 ++++
 cpus.c                  |  14 --
 hmp-commands.hx         |  16 ++
 hmp.c                   | 119 +++++++++++++
 hmp.h                   |   2 +
 hw/i386/pc.c            |   4 +-
 include/sysemu/cpus.h   |   1 -
 include/sysemu/sysemu.h |  16 +-
 monitor.c               |  21 +--
 numa.c                  | 444 ++++++++++++++++++++++++++++++++++++++++++++++++
 qapi-schema.json        | 142 ++++++++++++++++
 qemu-options.hx         |   6 +-
 qmp-commands.hx         |  90 ++++++++++
 vl.c                    | 160 ++---------------
 15 files changed, 885 insertions(+), 184 deletions(-)
 create mode 100644 numa.c

-- 
1.8.3.3.754.g9c3c367