From: Matthew Wilcox (Oracle) Date: Thu, 4 Mar 2021 16:09:17 +0000 (-0500) Subject: mm/writeback: Add folio_wait_writeback() X-Git-Tag: v6.6.17~9013^2~65 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=490e016f229a79dc7551e7f0e989d2304416c189;p=platform%2Fkernel%2Flinux-rpi.git mm/writeback: Add folio_wait_writeback() wait_on_page_writeback_killable() only has one caller, so convert it to call folio_wait_writeback_killable(). For the wait_on_page_writeback() callers, add a compatibility wrapper around folio_wait_writeback(). Turning PageWriteback() into folio_test_writeback() eliminates a call to compound_head() which saves 8 bytes and 15 bytes in the two functions. Unfortunately, that is more than offset by adding the wait_on_page_writeback compatibility wrapper for a net increase in text of 7 bytes. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Christoph Hellwig Acked-by: Jeff Layton Acked-by: Kirill A. Shutemov Acked-by: Vlastimil Babka Reviewed-by: William Kucharski Acked-by: Mike Rapoport Reviewed-by: David Howells --- diff --git a/fs/afs/write.c b/fs/afs/write.c index 2dfe3b3..5103328 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -861,7 +861,8 @@ int afs_fsync(struct file *file, loff_t start, loff_t end, int datasync) */ vm_fault_t afs_page_mkwrite(struct vm_fault *vmf) { - struct page *page = thp_head(vmf->page); + struct folio *folio = page_folio(vmf->page); + struct page *page = &folio->page; struct file *file = vmf->vma->vm_file; struct inode *inode = file_inode(file); struct afs_vnode *vnode = AFS_FS_I(inode); @@ -884,7 +885,7 @@ vm_fault_t afs_page_mkwrite(struct vm_fault *vmf) goto out; #endif - if (wait_on_page_writeback_killable(page)) + if (folio_wait_writeback_killable(folio)) goto out; if (lock_page_killable(page) < 0) @@ -894,8 +895,8 @@ vm_fault_t afs_page_mkwrite(struct vm_fault *vmf) * details the portion of the page we need to write back and we might * need to redirty the page if there's a problem. */ - if (wait_on_page_writeback_killable(page) < 0) { - unlock_page(page); + if (folio_wait_writeback_killable(folio) < 0) { + folio_unlock(folio); goto out; } diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index d9dcd33..e6013c0 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -766,7 +766,8 @@ static inline int wait_on_page_locked_killable(struct page *page) int put_and_wait_on_page_locked(struct page *page, int state); void wait_on_page_writeback(struct page *page); -int wait_on_page_writeback_killable(struct page *page); +void folio_wait_writeback(struct folio *folio); +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); diff --git a/mm/folio-compat.c b/mm/folio-compat.c index 526843d..41275da 100644 --- a/mm/folio-compat.c +++ b/mm/folio-compat.c @@ -23,3 +23,9 @@ void end_page_writeback(struct page *page) return folio_end_writeback(page_folio(page)); } EXPORT_SYMBOL(end_page_writeback); + +void wait_on_page_writeback(struct page *page) +{ + return folio_wait_writeback(page_folio(page)); +} +EXPORT_SYMBOL_GPL(wait_on_page_writeback); diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 4812a17..c7f40c9 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2873,33 +2873,51 @@ int __test_set_page_writeback(struct page *page, bool keep_write) } EXPORT_SYMBOL(__test_set_page_writeback); -/* - * Wait for a page to complete writeback +/** + * folio_wait_writeback - Wait for a folio to finish writeback. + * @folio: The folio to wait for. + * + * If the folio is currently being written back to storage, wait for the + * I/O 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_on_page_writeback(struct page *page) +void folio_wait_writeback(struct folio *folio) { - while (PageWriteback(page)) { - trace_wait_on_page_writeback(page, page_mapping(page)); - wait_on_page_bit(page, PG_writeback); + while (folio_test_writeback(folio)) { + trace_wait_on_page_writeback(&folio->page, folio_mapping(folio)); + wait_on_page_bit(&folio->page, PG_writeback); } } -EXPORT_SYMBOL_GPL(wait_on_page_writeback); +EXPORT_SYMBOL_GPL(folio_wait_writeback); -/* - * Wait for a page to complete writeback. Returns -EINTR if we get a - * fatal signal while waiting. +/** + * folio_wait_writeback_killable - Wait for a folio to finish writeback. + * @folio: The folio to wait for. + * + * If the folio is currently being written back to storage, wait for the + * I/O to complete or a fatal signal to arrive. + * + * 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. + * Return: 0 on success, -EINTR if we get a fatal signal while waiting. */ -int wait_on_page_writeback_killable(struct page *page) +int folio_wait_writeback_killable(struct folio *folio) { - while (PageWriteback(page)) { - trace_wait_on_page_writeback(page, page_mapping(page)); - if (wait_on_page_bit_killable(page, PG_writeback)) + while (folio_test_writeback(folio)) { + trace_wait_on_page_writeback(&folio->page, folio_mapping(folio)); + if (wait_on_page_bit_killable(&folio->page, PG_writeback)) return -EINTR; } return 0; } -EXPORT_SYMBOL_GPL(wait_on_page_writeback_killable); +EXPORT_SYMBOL_GPL(folio_wait_writeback_killable); /** * wait_for_stable_page() - wait for writeback to finish, if necessary.