| Message ID | 20230317105802.2634004-5-ryan.roberts@arm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | variable-order, large folios for anonymous memory | expand |
On 3/17/23 18:58, Ryan Roberts wrote: > Like folio_add_new_anon_rmap() but batch-rmaps all the pages belonging > to a folio, for effciency savings. > > Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> > --- > include/linux/rmap.h | 2 ++ > mm/rmap.c | 43 +++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 45 insertions(+) > > diff --git a/include/linux/rmap.h b/include/linux/rmap.h > index b87d01660412..d1d731650ce8 100644 > --- a/include/linux/rmap.h > +++ b/include/linux/rmap.h > @@ -196,6 +196,8 @@ void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, > unsigned long address); > void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, > unsigned long address); > +void folio_add_new_anon_rmap_range(struct folio *folio, > + struct vm_area_struct *vma, unsigned long address); > void page_add_file_rmap(struct page *, struct vm_area_struct *, > bool compound); > void page_remove_rmap(struct page *, struct vm_area_struct *, > diff --git a/mm/rmap.c b/mm/rmap.c > index 8632e02661ac..05a0c0a700e7 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -1302,6 +1302,49 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, > __page_set_anon_rmap(folio, &folio->page, vma, address, 1); > } > > +/** > + * folio_add_new_anon_rmap_range - Add mapping to a new anonymous potentially > + * large but definitely non-THP folio. > + * @folio: The folio to add the mapping to. > + * @vma: the vm area in which the mapping is added > + * @address: the user virtual address of the first page in the folio > + * > + * Like folio_add_new_anon_rmap() but must only be called for new *non-THP* > + * folios. Like folio_add_new_anon_rmap(), the inc-and-test is bypassed and the > + * folio does not have to be locked. All pages in the folio are individually > + * accounted. > + * > + * As the folio is new, it's assumed to be mapped exclusively by a single > + * process. > + */ > +void folio_add_new_anon_rmap_range(struct folio *folio, > + struct vm_area_struct *vma, unsigned long address) > +{ > + int i; > + int nr = folio_nr_pages(folio); > + struct page *page = &folio->page; > + > + VM_BUG_ON_VMA(address < vma->vm_start || > + address + (nr << PAGE_SHIFT) > vma->vm_end, vma); > + __folio_set_swapbacked(folio); > + > + if (folio_test_large(folio)) { > + /* increment count (starts at 0) */ > + atomic_set(&folio->_nr_pages_mapped, nr); > + } > + > + for (i = 0; i < nr; i++) { > + /* increment count (starts at -1) */ > + atomic_set(&page->_mapcount, 0); > + __page_set_anon_rmap(folio, page, vma, address, 1); > + page++; > + address += PAGE_SIZE; > + } > + > + __lruvec_stat_mod_folio(folio, NR_ANON_MAPPED, nr); It looks like you missed __page_set_anon_rmap() call here. Regards Yin, Fengwei > + > +} > + > /** > * page_add_file_rmap - add pte mapping to a file page > * @page: the page to add the mapping to > -- > 2.25.1 >
On 3/17/23 18:58, Ryan Roberts wrote: > Like folio_add_new_anon_rmap() but batch-rmaps all the pages belonging > to a folio, for effciency savings. > > Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> > --- > include/linux/rmap.h | 2 ++ > mm/rmap.c | 43 +++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 45 insertions(+) > > diff --git a/include/linux/rmap.h b/include/linux/rmap.h > index b87d01660412..d1d731650ce8 100644 > --- a/include/linux/rmap.h > +++ b/include/linux/rmap.h > @@ -196,6 +196,8 @@ void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, > unsigned long address); > void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, > unsigned long address); > +void folio_add_new_anon_rmap_range(struct folio *folio, > + struct vm_area_struct *vma, unsigned long address); > void page_add_file_rmap(struct page *, struct vm_area_struct *, > bool compound); > void page_remove_rmap(struct page *, struct vm_area_struct *, > diff --git a/mm/rmap.c b/mm/rmap.c > index 8632e02661ac..05a0c0a700e7 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -1302,6 +1302,49 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, > __page_set_anon_rmap(folio, &folio->page, vma, address, 1); > } > > +/** > + * folio_add_new_anon_rmap_range - Add mapping to a new anonymous potentially > + * large but definitely non-THP folio. > + * @folio: The folio to add the mapping to. > + * @vma: the vm area in which the mapping is added > + * @address: the user virtual address of the first page in the folio > + * > + * Like folio_add_new_anon_rmap() but must only be called for new *non-THP* > + * folios. Like folio_add_new_anon_rmap(), the inc-and-test is bypassed and the > + * folio does not have to be locked. All pages in the folio are individually > + * accounted. > + * > + * As the folio is new, it's assumed to be mapped exclusively by a single > + * process. > + */ > +void folio_add_new_anon_rmap_range(struct folio *folio, > + struct vm_area_struct *vma, unsigned long address) > +{ > + int i; > + int nr = folio_nr_pages(folio); > + struct page *page = &folio->page; > + > + VM_BUG_ON_VMA(address < vma->vm_start || > + address + (nr << PAGE_SHIFT) > vma->vm_end, vma); > + __folio_set_swapbacked(folio); > + > + if (folio_test_large(folio)) { > + /* increment count (starts at 0) */ > + atomic_set(&folio->_nr_pages_mapped, nr); > + } > + > + for (i = 0; i < nr; i++) { > + /* increment count (starts at -1) */ > + atomic_set(&page->_mapcount, 0); > + __page_set_anon_rmap(folio, page, vma, address, 1); My bad. You did call it here. Regards Yin, Fengwei > + page++; > + address += PAGE_SIZE; > + } > + > + __lruvec_stat_mod_folio(folio, NR_ANON_MAPPED, nr); > + > +} > + > /** > * page_add_file_rmap - add pte mapping to a file page > * @page: the page to add the mapping to > -- > 2.25.1 >
On 22/03/2023 07:10, Yin Fengwei wrote: > On 3/17/23 18:58, Ryan Roberts wrote: >> Like folio_add_new_anon_rmap() but batch-rmaps all the pages belonging >> to a folio, for effciency savings. >> >> Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> >> --- >> include/linux/rmap.h | 2 ++ >> mm/rmap.c | 43 +++++++++++++++++++++++++++++++++++++++++++ >> 2 files changed, 45 insertions(+) >> >> diff --git a/include/linux/rmap.h b/include/linux/rmap.h >> index b87d01660412..d1d731650ce8 100644 >> --- a/include/linux/rmap.h >> +++ b/include/linux/rmap.h >> @@ -196,6 +196,8 @@ void page_add_new_anon_rmap(struct page *, struct >> vm_area_struct *, >> unsigned long address); >> void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, >> unsigned long address); >> +void folio_add_new_anon_rmap_range(struct folio *folio, >> + struct vm_area_struct *vma, unsigned long address); >> void page_add_file_rmap(struct page *, struct vm_area_struct *, >> bool compound); >> void page_remove_rmap(struct page *, struct vm_area_struct *, >> diff --git a/mm/rmap.c b/mm/rmap.c >> index 8632e02661ac..05a0c0a700e7 100644 >> --- a/mm/rmap.c >> +++ b/mm/rmap.c >> @@ -1302,6 +1302,49 @@ void folio_add_new_anon_rmap(struct folio *folio, >> struct vm_area_struct *vma, >> __page_set_anon_rmap(folio, &folio->page, vma, address, 1); >> } >> >> +/** >> + * folio_add_new_anon_rmap_range - Add mapping to a new anonymous potentially >> + * large but definitely non-THP folio. >> + * @folio: The folio to add the mapping to. >> + * @vma: the vm area in which the mapping is added >> + * @address: the user virtual address of the first page in the folio >> + * >> + * Like folio_add_new_anon_rmap() but must only be called for new *non-THP* >> + * folios. Like folio_add_new_anon_rmap(), the inc-and-test is bypassed and the >> + * folio does not have to be locked. All pages in the folio are individually >> + * accounted. >> + * >> + * As the folio is new, it's assumed to be mapped exclusively by a single >> + * process. >> + */ >> +void folio_add_new_anon_rmap_range(struct folio *folio, >> + struct vm_area_struct *vma, unsigned long address) >> +{ >> + int i; >> + int nr = folio_nr_pages(folio); >> + struct page *page = &folio->page; >> + >> + VM_BUG_ON_VMA(address < vma->vm_start || >> + address + (nr << PAGE_SHIFT) > vma->vm_end, vma); >> + __folio_set_swapbacked(folio); >> + >> + if (folio_test_large(folio)) { >> + /* increment count (starts at 0) */ >> + atomic_set(&folio->_nr_pages_mapped, nr); >> + } >> + >> + for (i = 0; i < nr; i++) { >> + /* increment count (starts at -1) */ >> + atomic_set(&page->_mapcount, 0); >> + __page_set_anon_rmap(folio, page, vma, address, 1); > My bad. You did call it here. Yes, calling it per subpage to ensure every subpage is marked AnonExclusive. Although this does rely on calling it _first_ for the head page so that the index is set correctly. I think that all works out though. I did wonder if the order of the calls (__page_set_anon_rmap() vs __lruvec_stat_mod_folio() might matter - I've swapped them. But I haven't found any evidence that it does from reviewing the code. > > Regards > Yin, Fengwei > >> + page++; >> + address += PAGE_SIZE; >> + } >> + >> + __lruvec_stat_mod_folio(folio, NR_ANON_MAPPED, nr); >> + >> +} >> + >> /** >> * page_add_file_rmap - add pte mapping to a file page >> * @page: the page to add the mapping to >> -- >> 2.25.1 >> >
diff --git a/include/linux/rmap.h b/include/linux/rmap.h index b87d01660412..d1d731650ce8 100644 --- a/include/linux/rmap.h +++ b/include/linux/rmap.h @@ -196,6 +196,8 @@ void page_add_new_anon_rmap(struct page *, struct vm_area_struct *, unsigned long address); void folio_add_new_anon_rmap(struct folio *, struct vm_area_struct *, unsigned long address); +void folio_add_new_anon_rmap_range(struct folio *folio, + struct vm_area_struct *vma, unsigned long address); void page_add_file_rmap(struct page *, struct vm_area_struct *, bool compound); void page_remove_rmap(struct page *, struct vm_area_struct *, diff --git a/mm/rmap.c b/mm/rmap.c index 8632e02661ac..05a0c0a700e7 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1302,6 +1302,49 @@ void folio_add_new_anon_rmap(struct folio *folio, struct vm_area_struct *vma, __page_set_anon_rmap(folio, &folio->page, vma, address, 1); } +/** + * folio_add_new_anon_rmap_range - Add mapping to a new anonymous potentially + * large but definitely non-THP folio. + * @folio: The folio to add the mapping to. + * @vma: the vm area in which the mapping is added + * @address: the user virtual address of the first page in the folio + * + * Like folio_add_new_anon_rmap() but must only be called for new *non-THP* + * folios. Like folio_add_new_anon_rmap(), the inc-and-test is bypassed and the + * folio does not have to be locked. All pages in the folio are individually + * accounted. + * + * As the folio is new, it's assumed to be mapped exclusively by a single + * process. + */ +void folio_add_new_anon_rmap_range(struct folio *folio, + struct vm_area_struct *vma, unsigned long address) +{ + int i; + int nr = folio_nr_pages(folio); + struct page *page = &folio->page; + + VM_BUG_ON_VMA(address < vma->vm_start || + address + (nr << PAGE_SHIFT) > vma->vm_end, vma); + __folio_set_swapbacked(folio); + + if (folio_test_large(folio)) { + /* increment count (starts at 0) */ + atomic_set(&folio->_nr_pages_mapped, nr); + } + + for (i = 0; i < nr; i++) { + /* increment count (starts at -1) */ + atomic_set(&page->_mapcount, 0); + __page_set_anon_rmap(folio, page, vma, address, 1); + page++; + address += PAGE_SIZE; + } + + __lruvec_stat_mod_folio(folio, NR_ANON_MAPPED, nr); + +} + /** * page_add_file_rmap - add pte mapping to a file page * @page: the page to add the mapping to
Like folio_add_new_anon_rmap() but batch-rmaps all the pages belonging to a folio, for effciency savings. Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> --- include/linux/rmap.h | 2 ++ mm/rmap.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 45 insertions(+) -- 2.25.1