lkml.org 
[lkml]   [2019]   [Jan]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    Subject[PATCH v4 0/9] mmu notifier provide context informations
    Date
    From: Jérôme Glisse <jglisse@redhat.com>

    Hi Andrew, i see that you still have my event patch in you queue [1].
    This patchset replace that single patch and is broken down in further
    step so that it is easier to review and ascertain that no mistake were
    made during mechanical changes. Here are the step:

    Patch 1 - add the enum values
    Patch 2 - coccinelle semantic patch to convert all call site of
    mmu_notifier_range_init to default enum value and also
    to passing down the vma when it is available
    Patch 3 - update many call site to more accurate enum values
    Patch 4 - add the information to the mmu_notifier_range struct
    Patch 5 - helper to test if a range is updated to read only

    All the remaining patches are update to various driver to demonstrate
    how this new information get use by device driver. I build tested
    with make all and make all minus everything that enable mmu notifier
    ie building with MMU_NOTIFIER=no. Also tested with some radeon,amd
    gpu and intel gpu.

    If they are no objections i believe best plan would be to merge the
    the first 5 patches (all mm changes) through your queue for 5.1 and
    then to delay driver update to each individual driver tree for 5.2.
    This will allow each individual device driver maintainer time to more
    thouroughly test this more then my own testing.

    Note that i also intend to use this feature further in nouveau and
    HMM down the road. I also expect that other user like KVM might be
    interested into leveraging this new information to optimize some of
    there secondary page table invalidation.

    Here is an explaination on the rational for this patchset:


    CPU page table update can happens for many reasons, not only as a result
    of a syscall (munmap(), mprotect(), mremap(), madvise(), ...) but also
    as a result of kernel activities (memory compression, reclaim, migration,
    ...).

    This patch introduce a set of enums that can be associated with each of
    the events triggering a mmu notifier. Latter patches take advantages of
    those enum values.

    - UNMAP: munmap() or mremap()
    - CLEAR: page table is cleared (migration, compaction, reclaim, ...)
    - PROTECTION_VMA: change in access protections for the range
    - PROTECTION_PAGE: change in access protections for page in the range
    - SOFT_DIRTY: soft dirtyness tracking

    Being able to identify munmap() and mremap() from other reasons why the
    page table is cleared is important to allow user of mmu notifier to
    update their own internal tracking structure accordingly (on munmap or
    mremap it is not longer needed to track range of virtual address as it
    becomes invalid).

    [1] https://www.ozlabs.org/~akpm/mmotm/broken-out/mm-mmu_notifier-contextual-information-for-event-triggering-invalidation-v2.patch

    Cc: Christian König <christian.koenig@amd.com>
    Cc: Jan Kara <jack@suse.cz>
    Cc: Felix Kuehling <Felix.Kuehling@amd.com>
    Cc: Jason Gunthorpe <jgg@mellanox.com>
    Cc: Andrew Morton <akpm@linux-foundation.org>
    Cc: Matthew Wilcox <mawilcox@microsoft.com>
    Cc: Ross Zwisler <zwisler@kernel.org>
    Cc: Dan Williams <dan.j.williams@intel.com>
    Cc: Paolo Bonzini <pbonzini@redhat.com>
    Cc: Radim Krčmář <rkrcmar@redhat.com>
    Cc: Michal Hocko <mhocko@kernel.org>
    Cc: Ralph Campbell <rcampbell@nvidia.com>
    Cc: John Hubbard <jhubbard@nvidia.com>
    Cc: kvm@vger.kernel.org
    Cc: dri-devel@lists.freedesktop.org
    Cc: linux-rdma@vger.kernel.org
    Cc: linux-fsdevel@vger.kernel.org
    Cc: Arnd Bergmann <arnd@arndb.de>

    Jérôme Glisse (9):
    mm/mmu_notifier: contextual information for event enums
    mm/mmu_notifier: contextual information for event triggering
    invalidation
    mm/mmu_notifier: use correct mmu_notifier events for each invalidation
    mm/mmu_notifier: pass down vma and reasons why mmu notifier is
    happening
    mm/mmu_notifier: mmu_notifier_range_update_to_read_only() helper
    gpu/drm/radeon: optimize out the case when a range is updated to read
    only
    gpu/drm/amdgpu: optimize out the case when a range is updated to read
    only
    gpu/drm/i915: optimize out the case when a range is updated to read
    only
    RDMA/umem_odp: optimize out the case when a range is updated to read
    only

    drivers/gpu/drm/amd/amdgpu/amdgpu_mn.c | 13 ++++++++
    drivers/gpu/drm/i915/i915_gem_userptr.c | 16 ++++++++++
    drivers/gpu/drm/radeon/radeon_mn.c | 13 ++++++++
    drivers/infiniband/core/umem_odp.c | 22 +++++++++++--
    fs/proc/task_mmu.c | 3 +-
    include/linux/mmu_notifier.h | 42 ++++++++++++++++++++++++-
    include/rdma/ib_umem_odp.h | 1 +
    kernel/events/uprobes.c | 3 +-
    mm/huge_memory.c | 14 +++++----
    mm/hugetlb.c | 11 ++++---
    mm/khugepaged.c | 3 +-
    mm/ksm.c | 6 ++--
    mm/madvise.c | 3 +-
    mm/memory.c | 25 +++++++++------
    mm/migrate.c | 5 ++-
    mm/mmu_notifier.c | 10 ++++++
    mm/mprotect.c | 4 ++-
    mm/mremap.c | 3 +-
    mm/oom_kill.c | 3 +-
    mm/rmap.c | 6 ++--
    20 files changed, 171 insertions(+), 35 deletions(-)

    --
    2.17.2

    \
     
     \ /
      Last update: 2019-01-23 23:25    [W:4.299 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site