| Message ID | 20210715033704.692967-27-willy@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Memory folios | expand |
On Thu, Jul 15, 2021 at 04:35:12AM +0100, Matthew Wilcox (Oracle) wrote: > Move wait_for_stable_page() into the folio compatibility file. > folio_wait_stable() avoids a call to compound_head() and is 14 bytes > smaller than wait_for_stable_page() was. The net text size grows by 16 > bytes as a result of this patch. We can also remove thp_head() as this > was the last user. > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > Reviewed-by: Christoph Hellwig <hch@lst.de> > Acked-by: Jeff Layton <jlayton@kernel.org> > Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> > Acked-by: Vlastimil Babka <vbabka@suse.cz> > Reviewed-by: William Kucharski <william.kucharski@oracle.com> > Reviewed-by: David Howells <dhowells@redhat.com> > --- > include/linux/huge_mm.h | 15 --------------- > include/linux/pagemap.h | 1 + > mm/folio-compat.c | 6 ++++++ > mm/page-writeback.c | 24 ++++++++++++++---------- > 4 files changed, 21 insertions(+), 25 deletions(-) > > diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h > index f123e15d966e..f280f33ff223 100644 > --- a/include/linux/huge_mm.h > +++ b/include/linux/huge_mm.h > @@ -250,15 +250,6 @@ static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, > return NULL; > } > > -/** > - * thp_head - Head page of a transparent huge page. > - * @page: Any page (tail, head or regular) found in the page cache. kerneldoc will warn about missing return description > - */ > -static inline struct page *thp_head(struct page *page) > -{ > - return compound_head(page); > -} > - > /** > * thp_order - Order of a transparent huge page. > * @page: Head page of a transparent huge page. > @@ -336,12 +327,6 @@ static inline struct list_head *page_deferred_list(struct page *page) > #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; }) > #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; }) > > -static inline struct page *thp_head(struct page *page) > -{ > - VM_BUG_ON_PGFLAGS(PageTail(page), page); > - return page; > -} > - > static inline unsigned int thp_order(struct page *page) > { > VM_BUG_ON_PGFLAGS(PageTail(page), page); > diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h > index 0c5f53368fe9..96b62a2331fb 100644 > --- a/include/linux/pagemap.h > +++ b/include/linux/pagemap.h > @@ -772,6 +772,7 @@ int folio_wait_writeback_killable(struct folio *folio); > void end_page_writeback(struct page *page); > void folio_end_writeback(struct folio *folio); > void wait_for_stable_page(struct page *page); > +void folio_wait_stable(struct folio *folio); > > void __set_page_dirty(struct page *, struct address_space *, int warn); > int __set_page_dirty_nobuffers(struct page *page); > diff --git a/mm/folio-compat.c b/mm/folio-compat.c > index 41275dac7a92..3c83f03b80d7 100644 > --- a/mm/folio-compat.c > +++ b/mm/folio-compat.c > @@ -29,3 +29,9 @@ void wait_on_page_writeback(struct page *page) > return folio_wait_writeback(page_folio(page)); > } > EXPORT_SYMBOL_GPL(wait_on_page_writeback); > + > +void wait_for_stable_page(struct page *page) > +{ > + return folio_wait_stable(page_folio(page)); > +} > +EXPORT_SYMBOL_GPL(wait_for_stable_page); > diff --git a/mm/page-writeback.c b/mm/page-writeback.c > index c2c00e1533ad..a078e9786cc4 100644 > --- a/mm/page-writeback.c > +++ b/mm/page-writeback.c > @@ -2877,17 +2877,21 @@ int folio_wait_writeback_killable(struct folio *folio) > EXPORT_SYMBOL_GPL(folio_wait_writeback_killable); > > /** > - * wait_for_stable_page() - wait for writeback to finish, if necessary. > - * @page: The page to wait on. > + * folio_wait_stable() - wait for writeback to finish, if necessary. > + * @folio: The folio to wait on. > * > - * This function determines if the given page is related to a backing device > - * that requires page contents to be held stable during writeback. If so, then > - * it will wait for any pending writeback to complete. > + * This function determines if the given folio is related to a backing > + * device that requires folio contents to be held stable during writeback. > + * If so, then it will wait for any pending writeback to complete. > + * > + * Context: Sleeps. Must be called in process context and with > + * no spinlocks held. Caller should hold a reference on the folio. > + * If the folio is not locked, writeback may start again after writeback > + * has finished. > */ > -void wait_for_stable_page(struct page *page) > +void folio_wait_stable(struct folio *folio) > { > - page = thp_head(page); > - if (page->mapping->host->i_sb->s_iflags & SB_I_STABLE_WRITES) > - wait_on_page_writeback(page); > + if (folio->mapping->host->i_sb->s_iflags & SB_I_STABLE_WRITES) > + folio_wait_writeback(folio); > } > -EXPORT_SYMBOL_GPL(wait_for_stable_page); > +EXPORT_SYMBOL_GPL(folio_wait_stable); > -- > 2.30.2 > >
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h index f123e15d966e..f280f33ff223 100644 --- a/include/linux/huge_mm.h +++ b/include/linux/huge_mm.h @@ -250,15 +250,6 @@ static inline spinlock_t *pud_trans_huge_lock(pud_t *pud, return NULL; } -/** - * thp_head - Head page of a transparent huge page. - * @page: Any page (tail, head or regular) found in the page cache. - */ -static inline struct page *thp_head(struct page *page) -{ - return compound_head(page); -} - /** * thp_order - Order of a transparent huge page. * @page: Head page of a transparent huge page. @@ -336,12 +327,6 @@ static inline struct list_head *page_deferred_list(struct page *page) #define HPAGE_PUD_MASK ({ BUILD_BUG(); 0; }) #define HPAGE_PUD_SIZE ({ BUILD_BUG(); 0; }) -static inline struct page *thp_head(struct page *page) -{ - VM_BUG_ON_PGFLAGS(PageTail(page), page); - return page; -} - static inline unsigned int thp_order(struct page *page) { VM_BUG_ON_PGFLAGS(PageTail(page), page); diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 0c5f53368fe9..96b62a2331fb 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -772,6 +772,7 @@ int folio_wait_writeback_killable(struct folio *folio); void end_page_writeback(struct page *page); void folio_end_writeback(struct folio *folio); void wait_for_stable_page(struct page *page); +void folio_wait_stable(struct folio *folio); void __set_page_dirty(struct page *, struct address_space *, int warn); int __set_page_dirty_nobuffers(struct page *page); diff --git a/mm/folio-compat.c b/mm/folio-compat.c index 41275dac7a92..3c83f03b80d7 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -29,3 +29,9 @@ void wait_on_page_writeback(struct page *page) return folio_wait_writeback(page_folio(page)); } EXPORT_SYMBOL_GPL(wait_on_page_writeback); + +void wait_for_stable_page(struct page *page) +{ + return folio_wait_stable(page_folio(page)); +} +EXPORT_SYMBOL_GPL(wait_for_stable_page); diff --git a/mm/page-writeback.c b/mm/page-writeback.c index c2c00e1533ad..a078e9786cc4 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2877,17 +2877,21 @@ int folio_wait_writeback_killable(struct folio *folio) EXPORT_SYMBOL_GPL(folio_wait_writeback_killable); /** - * wait_for_stable_page() - wait for writeback to finish, if necessary. - * @page: The page to wait on. + * folio_wait_stable() - wait for writeback to finish, if necessary. + * @folio: The folio to wait on. * - * This function determines if the given page is related to a backing device - * that requires page contents to be held stable during writeback. If so, then - * it will wait for any pending writeback to complete. + * This function determines if the given folio is related to a backing + * device that requires folio contents to be held stable during writeback. + * If so, then it will wait for any pending writeback to complete. + * + * Context: Sleeps. Must be called in process context and with + * no spinlocks held. Caller should hold a reference on the folio. + * If the folio is not locked, writeback may start again after writeback + * has finished. */ -void wait_for_stable_page(struct page *page) +void folio_wait_stable(struct folio *folio) { - page = thp_head(page); - if (page->mapping->host->i_sb->s_iflags & SB_I_STABLE_WRITES) - wait_on_page_writeback(page); + if (folio->mapping->host->i_sb->s_iflags & SB_I_STABLE_WRITES) + folio_wait_writeback(folio); } -EXPORT_SYMBOL_GPL(wait_for_stable_page); +EXPORT_SYMBOL_GPL(folio_wait_stable);