[PATCH v2 00/10] Hyper-V: praravirtualized remote TLB flushing and hypercall improvements

[Vitaly Kuznetsov]

Changes since v1:
- Add a patch to build code in arch/x86/hyperv/ only when CONFIG_HYPERV is
  set.
- Add a patch to get maximum virtual/logical processor on Hyper-V.
- Add additional clobbers to hypercalls [Jork Loeser]
- Add variable header size support to rep hypercalls.
- Rename vmbus_cpu_number_to_vp_number -> hv_cpu_number_to_vp_number
  [K. Y. Srinivasan]
- Remove spinlocks from hyperv_flush_tlb_others() [Jork Loeser]
- Account for mm==NULL in hyperv_flush_tlb_others() [Simon Xiao]
- Add support for HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX/LIST_EX hypercalls
  to support >64 vCPUs [K. Y. Srinivasan, Jork Loeser]
- Move hyperv.h to arch-specific place [Steven Rostedt]
- Rebased to the latest char-misc-next tree.

Original descriptions:

Hyper-V supports hypercalls for doing local and remote TLB flushing and
gives its guests hints when using hypercall is preferred. While doing
hypercalls for local TLB flushes is probably not practical (and is not
being suggested by modern Hyper-V versions) remote TLB flush with a
hypercall brings significant improvement.

To test the series I wrote a special 'TLB trasher': on a 16 vCPU guest I
was creating 32 threads which were doing 100000 mmap/munmaps each on some
big file. Here are the results:

Before:
# time ./pthread_mmap ./randfile 
real	3m44.994s
user	0m3.829s
sys	3m36.323s

After:
# time ./pthread_mmap ./randfile 
real	2m57.145s
user	0m3.797s
sys	2m34.812s

This series brings a number of small improvements along the way: fast
hypercall implementation and using it for event signaling, rep hypercalls
implementation, hyperv tracing subsystem (which only traces the newly added
remote TLB flush for now).

Vitaly Kuznetsov (10):
  x86/hyper-v: include hyperv/ only when CONFIG_HYPERV is set
  x86/hyper-v: stash the max number of virtual/logical processor
  x86/hyper-v: make hv_do_hypercall() inline
  x86/hyper-v: fast hypercall implementation
  hyper-v: use fast hypercall for HVCALL_SIGNAL_EVENT
  x86/hyper-v: implement rep hypercalls
  hyper-v: globalize vp_index
  x86/hyper-v: use hypercall for remote TLB flush
  x86/hyper-v: support extended CPU ranges for TLB flush hypercalls
  tracing/hyper-v: trace hyperv_mmu_flush_tlb_others()

 MAINTAINERS                         |   1 +
 arch/x86/Kbuild                     |   4 +-
 arch/x86/hyperv/Makefile            |   2 +-
 arch/x86/hyperv/hv_init.c           |  90 ++++++------
 arch/x86/hyperv/mmu.c               | 270 ++++++++++++++++++++++++++++++++++++
 arch/x86/include/asm/mshyperv.h     | 148 +++++++++++++++++++-
 arch/x86/include/asm/trace/hyperv.h |  34 +++++
 arch/x86/include/uapi/asm/hyperv.h  |  36 +++++
 arch/x86/kernel/cpu/mshyperv.c      |  14 +-
 drivers/hv/channel_mgmt.c           |  22 ++-
 drivers/hv/connection.c             |   8 +-
 drivers/hv/hv.c                     |   9 --
 drivers/hv/hyperv_vmbus.h           |  11 --
 drivers/hv/vmbus_drv.c              |  17 ---
 drivers/pci/host/pci-hyperv.c       |   4 +-
 include/linux/hyperv.h              |  21 ++-
 16 files changed, 567 insertions(+), 124 deletions(-)
 create mode 100644 arch/x86/hyperv/mmu.c
 create mode 100644 arch/x86/include/asm/trace/hyperv.h

-- 
2.9.3