mbox series

[RESEND,0/7] Add FOLL_LONGTERM to GUP fast and use it

Message ID 20190317183438.2057-1-ira.weiny@intel.com
Headers show
Series Add FOLL_LONGTERM to GUP fast and use it | expand

Message

Ira Weiny March 17, 2019, 6:34 p.m. UTC
From: Ira Weiny <ira.weiny@intel.com>

Resending after rebasing to the latest mm tree.

HFI1, qib, and mthca, use get_user_pages_fast() due to it performance
advantages.  These pages can be held for a significant time.  But
get_user_pages_fast() does not protect against mapping FS DAX pages.

Introduce FOLL_LONGTERM and use this flag in get_user_pages_fast() which
retains the performance while also adding the FS DAX checks.  XDP has also
shown interest in using this functionality.[1]

In addition we change get_user_pages() to use the new FOLL_LONGTERM flag and
remove the specialized get_user_pages_longterm call.

[1] https://lkml.org/lkml/2019/2/11/1789

Ira Weiny (7):
  mm/gup: Replace get_user_pages_longterm() with FOLL_LONGTERM
  mm/gup: Change write parameter to flags in fast walk
  mm/gup: Change GUP fast to use flags rather than a write 'bool'
  mm/gup: Add FOLL_LONGTERM capability to GUP fast
  IB/hfi1: Use the new FOLL_LONGTERM flag to get_user_pages_fast()
  IB/qib: Use the new FOLL_LONGTERM flag to get_user_pages_fast()
  IB/mthca: Use the new FOLL_LONGTERM flag to get_user_pages_fast()

 arch/mips/mm/gup.c                          |  11 +-
 arch/powerpc/kvm/book3s_64_mmu_hv.c         |   4 +-
 arch/powerpc/kvm/e500_mmu.c                 |   2 +-
 arch/powerpc/mm/mmu_context_iommu.c         |   3 +-
 arch/s390/kvm/interrupt.c                   |   2 +-
 arch/s390/mm/gup.c                          |  12 +-
 arch/sh/mm/gup.c                            |  11 +-
 arch/sparc/mm/gup.c                         |   9 +-
 arch/x86/kvm/paging_tmpl.h                  |   2 +-
 arch/x86/kvm/svm.c                          |   2 +-
 drivers/fpga/dfl-afu-dma-region.c           |   2 +-
 drivers/gpu/drm/via/via_dmablit.c           |   3 +-
 drivers/infiniband/core/umem.c              |   5 +-
 drivers/infiniband/hw/hfi1/user_pages.c     |   5 +-
 drivers/infiniband/hw/mthca/mthca_memfree.c |   3 +-
 drivers/infiniband/hw/qib/qib_user_pages.c  |   8 +-
 drivers/infiniband/hw/qib/qib_user_sdma.c   |   2 +-
 drivers/infiniband/hw/usnic/usnic_uiom.c    |   9 +-
 drivers/media/v4l2-core/videobuf-dma-sg.c   |   6 +-
 drivers/misc/genwqe/card_utils.c            |   2 +-
 drivers/misc/vmw_vmci/vmci_host.c           |   2 +-
 drivers/misc/vmw_vmci/vmci_queue_pair.c     |   6 +-
 drivers/platform/goldfish/goldfish_pipe.c   |   3 +-
 drivers/rapidio/devices/rio_mport_cdev.c    |   4 +-
 drivers/sbus/char/oradax.c                  |   2 +-
 drivers/scsi/st.c                           |   3 +-
 drivers/staging/gasket/gasket_page_table.c  |   4 +-
 drivers/tee/tee_shm.c                       |   2 +-
 drivers/vfio/vfio_iommu_spapr_tce.c         |   3 +-
 drivers/vfio/vfio_iommu_type1.c             |   3 +-
 drivers/vhost/vhost.c                       |   2 +-
 drivers/video/fbdev/pvr2fb.c                |   2 +-
 drivers/virt/fsl_hypervisor.c               |   2 +-
 drivers/xen/gntdev.c                        |   2 +-
 fs/io_uring.c                               |   5 +-
 fs/orangefs/orangefs-bufmap.c               |   2 +-
 include/linux/mm.h                          |  18 +-
 kernel/futex.c                              |   2 +-
 lib/iov_iter.c                              |   7 +-
 mm/gup.c                                    | 258 ++++++++++++--------
 mm/gup_benchmark.c                          |   5 +-
 mm/util.c                                   |   8 +-
 net/ceph/pagevec.c                          |   2 +-
 net/rds/info.c                              |   2 +-
 net/rds/rdma.c                              |   3 +-
 net/xdp/xdp_umem.c                          |   4 +-
 46 files changed, 262 insertions(+), 197 deletions(-)

Comments

Andrew Morton March 19, 2019, 10:19 p.m. UTC | #1
On Sun, 17 Mar 2019 11:34:31 -0700 ira.weiny@intel.com wrote:

> Resending after rebasing to the latest mm tree.
> 
> HFI1, qib, and mthca, use get_user_pages_fast() due to it performance
> advantages.  These pages can be held for a significant time.  But
> get_user_pages_fast() does not protect against mapping FS DAX pages.
> 
> Introduce FOLL_LONGTERM and use this flag in get_user_pages_fast() which
> retains the performance while also adding the FS DAX checks.  XDP has also
> shown interest in using this functionality.[1]
> 
> In addition we change get_user_pages() to use the new FOLL_LONGTERM flag and
> remove the specialized get_user_pages_longterm call.

It would be helpful to include your response to Christoph's question
(http://lkml.kernel.org/r/20190220180255.GA12020@iweiny-DESK2.sc.intel.com)
in the changelog.  Because if one person was wondering about this,
others will likely do so.

We have no record of acks or reviewed-by's.  At least one was missed
(http://lkml.kernel.org/r/CAOg9mSTTcD-9bCSDfC0WRYqfVrNB4TwOzL0c4+6QXi-N_Y43Vw@mail.gmail.com),
but that is very very partial.

This patchset is fairly DAX-centered, but Dan wasn't cc'ed!

So ho hum.  I'll scoop them up and shall make the above changes to the
[1/n] changelog, but we still have some work to do.
Ira Weiny March 21, 2019, 8:40 a.m. UTC | #2
On Tue, Mar 19, 2019 at 03:19:30PM -0700, Andrew Morton wrote:
> On Sun, 17 Mar 2019 11:34:31 -0700 ira.weiny@intel.com wrote:
> 
> > Resending after rebasing to the latest mm tree.
> > 
> > HFI1, qib, and mthca, use get_user_pages_fast() due to it performance
> > advantages.  These pages can be held for a significant time.  But
> > get_user_pages_fast() does not protect against mapping FS DAX pages.
> > 
> > Introduce FOLL_LONGTERM and use this flag in get_user_pages_fast() which
> > retains the performance while also adding the FS DAX checks.  XDP has also
> > shown interest in using this functionality.[1]
> > 
> > In addition we change get_user_pages() to use the new FOLL_LONGTERM flag and
> > remove the specialized get_user_pages_longterm call.
> 
> It would be helpful to include your response to Christoph's question
> (http://lkml.kernel.org/r/20190220180255.GA12020@iweiny-DESK2.sc.intel.com)
> in the changelog.  Because if one person was wondering about this,
> others will likely do so.
> 
> We have no record of acks or reviewed-by's.  At least one was missed
> (http://lkml.kernel.org/r/CAOg9mSTTcD-9bCSDfC0WRYqfVrNB4TwOzL0c4+6QXi-N_Y43Vw@mail.gmail.com),
> but that is very very partial.

That is my bad.  Sorry to Mike.  And I have added him.

> 
> This patchset is fairly DAX-centered, but Dan wasn't cc'ed!

Agreed, I'm new to changing things which affect this many sub-systems and I
struggled with who should be CC'ed (get_maintainer.pl returned a very large
list  :-(.

I fear I may have cc'ed too many people, and the wrong people apparently, so
that may be affecting the review...

So again my apologies.  I don't know if Dan is going to get a chance to put a
reviewed-by on them this week but I thought I would send this note to let you
know I'm not ignoring your feedback.  Just waiting a bit before resending to
hopefully get some more acks/reviewed bys.

Thanks,
Ira

> 
> So ho hum.  I'll scoop them up and shall make the above changes to the
> [1/n] changelog, but we still have some work to do.
>