Re: [PATCH v14 030/138] mm/filemap: Add folio private_2 functions

Mike Rapoport
2021-07-21T09:47:38Z

On Thu, Jul 15, 2021 at 04:35:16AM +0100, Matthew Wilcox (Oracle) wrote:
> end_page_private_2() becomes folio_end_private_2(),
> wait_on_page_private_2() becomes folio_wait_private_2() and
> wait_on_page_private_2_killable() becomes folio_wait_private_2_killable().
>
> Adjust the fscache equivalents to call page_folio() before calling these
> functions to avoid adding wrappers. Ends up costing 1 byte of text
> in ceph & netfs, but the core shrinks by three calls to page_folio().
>
> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> Acked-by: Vlastimil Babka <vbabka@suse.cz>
> Reviewed-by: William Kucharski <william.kucharski@oracle.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> Reviewed-by: David Howells <dhowells@redhat.com>
> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> ---
> include/linux/netfs.h | 6 +++---
> include/linux/pagemap.h | 6 +++---
> mm/filemap.c | 37 ++++++++++++++++---------------------
> 3 files changed, 22 insertions(+), 27 deletions(-)
>
> diff --git a/include/linux/netfs.h b/include/linux/netfs.h
> index 9062adfa2fb9..fad8c6209edd 100644
> --- a/include/linux/netfs.h
> +++ b/include/linux/netfs.h
> @@ -55,7 +55,7 @@ static inline void set_page_fscache(struct page *page)
> */
> static inline void end_page_fscache(struct page *page)
> {
> - end_page_private_2(page);
> + folio_end_private_2(page_folio(page));
> }
>
> /**
> @@ -66,7 +66,7 @@ static inline void end_page_fscache(struct page *page)
> */
> static inline void wait_on_page_fscache(struct page *page)
> {
> - wait_on_page_private_2(page);
> + folio_wait_private_2(page_folio(page));
> }
>
> /**
> @@ -82,7 +82,7 @@ static inline void wait_on_page_fscache(struct page *page)
> */
> static inline int wait_on_page_fscache_killable(struct page *page)
> {
> - return wait_on_page_private_2_killable(page);
> + return folio_wait_private_2_killable(page_folio(page));
> }
>
> enum netfs_read_source {
> diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
> index c8e74d67b01f..edf58a581bce 100644
> --- a/include/linux/pagemap.h
> +++ b/include/linux/pagemap.h
> @@ -796,9 +796,9 @@ static inline void set_page_private_2(struct page *page)
> SetPagePrivate2(page);
> }
>
> -void end_page_private_2(struct page *page);
> -void wait_on_page_private_2(struct page *page);
> -int wait_on_page_private_2_killable(struct page *page);
> +void folio_end_private_2(struct folio *folio);
> +void folio_wait_private_2(struct folio *folio);
> +int folio_wait_private_2_killable(struct folio *folio);
>
> /*
> * Add an arbitrary waiter to a page's wait queue
> diff --git a/mm/filemap.c b/mm/filemap.c
> index 1ecaece68019..a5d02ec62eb6 100644
> --- a/mm/filemap.c
> +++ b/mm/filemap.c
> @@ -1451,56 +1451,51 @@ void folio_unlock(struct folio *folio)
> EXPORT_SYMBOL(folio_unlock);
>
> /**
> - * end_page_private_2 - Clear PG_private_2 and release any waiters
> - * @page: The page
> + * folio_end_private_2 - Clear PG_private_2 and wake any waiters.
> + * @folio: The folio.
> *
> - * Clear the PG_private_2 bit on a page and wake up any sleepers waiting for
> - * this. The page ref held for PG_private_2 being set is released.
> + * Clear the PG_private_2 bit on a folio and wake up any sleepers waiting for
> + * it. The page ref held for PG_private_2 being set is released.

^ folio reference

> *
> * This is, for example, used when a netfs page is being written to a local
> * disk cache, thereby allowing writes to the cache for the same page to be
> * serialised.
> */
> -void end_page_private_2(struct page *page)
> +void folio_end_private_2(struct folio *folio)
> {
> - struct folio *folio = page_folio(page);
> -
> VM_BUG_ON_FOLIO(!folio_test_private_2(folio), folio);
> clear_bit_unlock(PG_private_2, folio_flags(folio, 0));
> folio_wake_bit(folio, PG_private_2);
> folio_put(folio);
> }
> -EXPORT_SYMBOL(end_page_private_2);
> +EXPORT_SYMBOL(folio_end_private_2);
>
> /**
> - * wait_on_page_private_2 - Wait for PG_private_2 to be cleared on a page
> - * @page: The page to wait on
> + * folio_wait_private_2 - Wait for PG_private_2 to be cleared on a page.

^ folio
> + * @folio: The folio to wait on.
> *
> - * Wait for PG_private_2 (aka PG_fscache) to be cleared on a page.
> + * Wait for PG_private_2 (aka PG_fscache) to be cleared on a folio.
> */
> -void wait_on_page_private_2(struct page *page)
> +void folio_wait_private_2(struct folio *folio)
> {
> - struct folio *folio = page_folio(page);
> -
> while (folio_test_private_2(folio))
> folio_wait_bit(folio, PG_private_2);
> }
> -EXPORT_SYMBOL(wait_on_page_private_2);
> +EXPORT_SYMBOL(folio_wait_private_2);
>
> /**
> - * wait_on_page_private_2_killable - Wait for PG_private_2 to be cleared on a page
> - * @page: The page to wait on
> + * folio_wait_private_2_killable - Wait for PG_private_2 to be cleared on a folio.
> + * @folio: The folio to wait on.
> *
> - * Wait for PG_private_2 (aka PG_fscache) to be cleared on a page or until a
> + * Wait for PG_private_2 (aka PG_fscache) to be cleared on a folio or until a
> * fatal signal is received by the calling task.
> *
> * Return:
> * - 0 if successful.
> * - -EINTR if a fatal signal was encountered.
> */
> -int wait_on_page_private_2_killable(struct page *page)
> +int folio_wait_private_2_killable(struct folio *folio)
> {
> - struct folio *folio = page_folio(page);
> int ret = 0;
>
> while (folio_test_private_2(folio)) {
> @@ -1511,7 +1506,7 @@ int wait_on_page_private_2_killable(struct page *page)
>
> return ret;
> }
> -EXPORT_SYMBOL(wait_on_page_private_2_killable);
> +EXPORT_SYMBOL(folio_wait_private_2_killable);
>
> /**
> * folio_end_writeback - End writeback against a folio.
> --
> 2.30.2
>
>

--
Sincerely yours,
Mike.