Messages in this thread | | | Subject | Re: [PATCH v5 5/9] mm/mmu_notifier: contextual information for event triggering invalidation v2 | From | Ralph Campbell <> | Date | Fri, 22 Feb 2019 13:25:03 -0800 |
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On 2/19/19 12:04 PM, jglisse@redhat.com wrote: > From: Jérôme Glisse <jglisse@redhat.com> > > 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, > ...). > > Users of mmu notifier API track changes to the CPU page table and take > specific action for them. While current API only provide range of virtual > address affected by the change, not why the changes is happening. > > This patchset do the initial mechanical convertion of all the places that > calls mmu_notifier_range_init to also provide the default MMU_NOTIFY_UNMAP > event as well as the vma if it is know (most invalidation happens against > a given vma). Passing down the vma allows the users of mmu notifier to > inspect the new vma page protection. > > The MMU_NOTIFY_UNMAP is always the safe default as users of mmu notifier > should assume that every for the range is going away when that event > happens. A latter patch do convert mm call path to use a more appropriate > events for each call. > > Changes since v1: > - add the flags parameter to init range flags > > This is done as 2 patches so that no call site is forgotten especialy > as it uses this following coccinelle patch: > > %<---------------------------------------------------------------------- > @@ > identifier I1, I2, I3, I4; > @@ > static inline void mmu_notifier_range_init(struct mmu_notifier_range *I1, > +enum mmu_notifier_event event, > +unsigned flags, > +struct vm_area_struct *vma, > struct mm_struct *I2, unsigned long I3, unsigned long I4) { ... } > > @@ > @@ > -#define mmu_notifier_range_init(range, mm, start, end) > +#define mmu_notifier_range_init(range, event, flags, vma, mm, start, end) > > @@ > expression E1, E3, E4; > identifier I1; > @@ > <... > mmu_notifier_range_init(E1, > +MMU_NOTIFY_UNMAP, 0, I1, > I1->vm_mm, E3, E4) > ...> > > @@ > expression E1, E2, E3, E4; > identifier FN, VMA; > @@ > FN(..., struct vm_area_struct *VMA, ...) { > <... > mmu_notifier_range_init(E1, > +MMU_NOTIFY_UNMAP, 0, VMA, > E2, E3, E4) > ...> } > > @@ > expression E1, E2, E3, E4; > identifier FN, VMA; > @@ > FN(...) { > struct vm_area_struct *VMA; > <... > mmu_notifier_range_init(E1, > +MMU_NOTIFY_UNMAP, 0, VMA, > E2, E3, E4) > ...> } > > @@ > expression E1, E2, E3, E4; > identifier FN; > @@ > FN(...) { > <... > mmu_notifier_range_init(E1, > +MMU_NOTIFY_UNMAP, 0, NULL, > E2, E3, E4) > ...> } > ---------------------------------------------------------------------->% > > Applied with: > spatch --all-includes --sp-file mmu-notifier.spatch fs/proc/task_mmu.c --in-place > spatch --sp-file mmu-notifier.spatch --dir kernel/events/ --in-place > spatch --sp-file mmu-notifier.spatch --dir mm --in-place > > Signed-off-by: Jérôme Glisse <jglisse@redhat.com> > Cc: Christian König <christian.koenig@amd.com> > Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> > Cc: Jani Nikula <jani.nikula@linux.intel.com> > Cc: Rodrigo Vivi <rodrigo.vivi@intel.com> > Cc: Jan Kara <jack@suse.cz> > Cc: Andrea Arcangeli <aarcange@redhat.com> > Cc: Peter Xu <peterx@redhat.com> > Cc: Felix Kuehling <Felix.Kuehling@amd.com> > Cc: Jason Gunthorpe <jgg@mellanox.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: Christian Koenig <christian.koenig@amd.com> > 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: Arnd Bergmann <arnd@arndb.de> > ---
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
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