Message ID | 20180824192549.30844-6-jglisse@redhat.com (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | HMM updates, improvements and fixes | expand |
On Fri, Aug 24, 2018 at 03:25:47PM -0400, jglisse@redhat.com wrote: > From: Jérôme Glisse <jglisse@redhat.com> > > Use a structure to gather all the parameters for the update callback. > This make it easier when adding new parameters by avoiding having to > update all callback function signature. > > Signed-off-by: Jérôme Glisse <jglisse@redhat.com> > Cc: Ralph Campbell <rcampbell@nvidia.com> > Cc: John Hubbard <jhubbard@nvidia.com> > Cc: Andrew Morton <akpm@linux-foundation.org> > --- > include/linux/hmm.h | 25 +++++++++++++++++-------- > mm/hmm.c | 27 ++++++++++++++------------- > 2 files changed, 31 insertions(+), 21 deletions(-) > > diff --git a/include/linux/hmm.h b/include/linux/hmm.h > index 1ff4bae7ada7..a7f7600b6bb0 100644 > --- a/include/linux/hmm.h > +++ b/include/linux/hmm.h > @@ -274,13 +274,26 @@ static inline uint64_t hmm_pfn_from_pfn(const struct hmm_range *range, > struct hmm_mirror; > > /* > - * enum hmm_update_type - type of update > + * enum hmm_update_event - type of update > * @HMM_UPDATE_INVALIDATE: invalidate range (no indication as to why) > */ > -enum hmm_update_type { > +enum hmm_update_event { > HMM_UPDATE_INVALIDATE, > }; > > +/* > + * struct hmm_update - HMM update informations for callback > + * > + * @start: virtual start address of the range to update > + * @end: virtual end address of the range to update > + * @event: event triggering the update (what is happening) > + */ > +struct hmm_update { > + unsigned long start; > + unsigned long end; > + enum hmm_update_event event; > +}; > + I wonder if you want to add further information about the range, like page_size, I guess the other side does not care about the size. Do we care about sending multiple discontig ranges in hmm_update? Should it be an array? Balbir Singh
On Fri, Aug 31, 2018 at 09:11:48AM +1000, Balbir Singh wrote: > On Fri, Aug 24, 2018 at 03:25:47PM -0400, jglisse@redhat.com wrote: > > From: Jérôme Glisse <jglisse@redhat.com> > > > > Use a structure to gather all the parameters for the update callback. > > This make it easier when adding new parameters by avoiding having to > > update all callback function signature. > > > > Signed-off-by: Jérôme Glisse <jglisse@redhat.com> > > Cc: Ralph Campbell <rcampbell@nvidia.com> > > Cc: John Hubbard <jhubbard@nvidia.com> > > Cc: Andrew Morton <akpm@linux-foundation.org> > > --- > > include/linux/hmm.h | 25 +++++++++++++++++-------- > > mm/hmm.c | 27 ++++++++++++++------------- > > 2 files changed, 31 insertions(+), 21 deletions(-) > > > > diff --git a/include/linux/hmm.h b/include/linux/hmm.h > > index 1ff4bae7ada7..a7f7600b6bb0 100644 > > --- a/include/linux/hmm.h > > +++ b/include/linux/hmm.h > > @@ -274,13 +274,26 @@ static inline uint64_t hmm_pfn_from_pfn(const struct hmm_range *range, > > struct hmm_mirror; > > > > /* > > - * enum hmm_update_type - type of update > > + * enum hmm_update_event - type of update > > * @HMM_UPDATE_INVALIDATE: invalidate range (no indication as to why) > > */ > > -enum hmm_update_type { > > +enum hmm_update_event { > > HMM_UPDATE_INVALIDATE, > > }; > > > > +/* > > + * struct hmm_update - HMM update informations for callback > > + * > > + * @start: virtual start address of the range to update > > + * @end: virtual end address of the range to update > > + * @event: event triggering the update (what is happening) > > + */ > > +struct hmm_update { > > + unsigned long start; > > + unsigned long end; > > + enum hmm_update_event event; > > +}; > > + > > I wonder if you want to add further information about the range, > like page_size, I guess the other side does not care about the > size. Do we care about sending multiple discontig ranges in > hmm_update? Should it be an array? > > Balbir Singh This is a range of virtual address if a huge page is fully unmapped then the range will cover the full huge page. It mirror mmu notifier range callback because 99% of the time it is just use to pass down mmu notifier invalidation. So we don't care about multi range at least not yet. Nor do we care about page size as it might vary in the range (range can have a mix of THP and regular page) moreover the device driver usualy ignore the page size. Cheers, Jérôme
diff --git a/include/linux/hmm.h b/include/linux/hmm.h index 1ff4bae7ada7..a7f7600b6bb0 100644 --- a/include/linux/hmm.h +++ b/include/linux/hmm.h @@ -274,13 +274,26 @@ static inline uint64_t hmm_pfn_from_pfn(const struct hmm_range *range, struct hmm_mirror; /* - * enum hmm_update_type - type of update + * enum hmm_update_event - type of update * @HMM_UPDATE_INVALIDATE: invalidate range (no indication as to why) */ -enum hmm_update_type { +enum hmm_update_event { HMM_UPDATE_INVALIDATE, }; +/* + * struct hmm_update - HMM update informations for callback + * + * @start: virtual start address of the range to update + * @end: virtual end address of the range to update + * @event: event triggering the update (what is happening) + */ +struct hmm_update { + unsigned long start; + unsigned long end; + enum hmm_update_event event; +}; + /* * struct hmm_mirror_ops - HMM mirror device operations callback * @@ -300,9 +313,7 @@ struct hmm_mirror_ops { /* sync_cpu_device_pagetables() - synchronize page tables * * @mirror: pointer to struct hmm_mirror - * @update_type: type of update that occurred to the CPU page table - * @start: virtual start address of the range to update - * @end: virtual end address of the range to update + * @update: update informations (see struct hmm_update) * * This callback ultimately originates from mmu_notifiers when the CPU * page table is updated. The device driver must update its page table @@ -314,9 +325,7 @@ struct hmm_mirror_ops { * synchronous call. */ void (*sync_cpu_device_pagetables)(struct hmm_mirror *mirror, - enum hmm_update_type update_type, - unsigned long start, - unsigned long end); + const struct hmm_update *update); }; /* diff --git a/mm/hmm.c b/mm/hmm.c index 659efc9aada6..debd2f734ab5 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -127,9 +127,7 @@ void hmm_mm_destroy(struct mm_struct *mm) } static void hmm_invalidate_range(struct hmm *hmm, - enum hmm_update_type action, - unsigned long start, - unsigned long end) + const struct hmm_update *update) { struct hmm_mirror *mirror; struct hmm_range *range; @@ -138,21 +136,20 @@ static void hmm_invalidate_range(struct hmm *hmm, list_for_each_entry(range, &hmm->ranges, list) { unsigned long addr, idx, npages; - if (end < range->start || start >= range->end) + if (update->end < range->start || update->start >= range->end) continue; range->valid = false; - addr = max(start, range->start); + addr = max(update->start, range->start); idx = (addr - range->start) >> PAGE_SHIFT; - npages = (min(range->end, end) - addr) >> PAGE_SHIFT; + npages = (min(range->end, update->end) - addr) >> PAGE_SHIFT; memset(&range->pfns[idx], 0, sizeof(*range->pfns) * npages); } spin_unlock(&hmm->lock); down_read(&hmm->mirrors_sem); list_for_each_entry(mirror, &hmm->mirrors, list) - mirror->ops->sync_cpu_device_pagetables(mirror, action, - start, end); + mirror->ops->sync_cpu_device_pagetables(mirror, update); up_read(&hmm->mirrors_sem); } @@ -183,10 +180,10 @@ static void hmm_release(struct mmu_notifier *mn, struct mm_struct *mm) } static int hmm_invalidate_range_start(struct mmu_notifier *mn, - struct mm_struct *mm, - unsigned long start, - unsigned long end, - bool blockable) + struct mm_struct *mm, + unsigned long start, + unsigned long end, + bool blockable) { struct hmm *hmm = mm->hmm; @@ -202,11 +199,15 @@ static void hmm_invalidate_range_end(struct mmu_notifier *mn, unsigned long start, unsigned long end) { + struct hmm_update update; struct hmm *hmm = mm->hmm; VM_BUG_ON(!hmm); - hmm_invalidate_range(mm->hmm, HMM_UPDATE_INVALIDATE, start, end); + update.start = start; + update.end = end; + update.event = HMM_UPDATE_INVALIDATE; + hmm_invalidate_range(hmm, &update); } static const struct mmu_notifier_ops hmm_mmu_notifier_ops = {