From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 946E8C07E95 for ; Tue, 20 Jul 2021 10:58:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 755B86113C for ; Tue, 20 Jul 2021 10:58:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234770AbhGTKSC (ORCPT ); Tue, 20 Jul 2021 06:18:02 -0400 Received: from mail.kernel.org ([198.145.29.99]:35902 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237361AbhGTKGR (ORCPT ); Tue, 20 Jul 2021 06:06:17 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4CF836120C; Tue, 20 Jul 2021 10:46:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1626778015; bh=4f6YnMgD2RU9zg52iddrIGKgcdG3x9kyvHxgH0wPP/I=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=hWJxuVCvtttXfrkmqS8dtMizbfcc5C/RxNVIuTMN0U+87QVm/tPKxCELgnAwaFUBL kg40BLodTEeYi56mvWycACQWRTwAKO6fLUnxeCa+XAXSz6YyRfQRG7NydwPRkIJnEq O2T9ofBOZzc9aWifrOHBR2FtMMeYJU7WpepZbHPY42TthTWUUuX37MuNs3i5JtusJ+ sBtOnJY6PNjgwj62LIqq3uSNdIeJKpHf97Yfq6pSBMsMumhCRjw61t5hISIaWjCe8r hUQYZwZ8TSDyQqgkEj7nWXSSVDAWpbCfn+CijVH5zvw5kFszEA2W+x1diWJccMnF6T Fw8IbALBvI4wg== Date: Tue, 20 Jul 2021 13:46:47 +0300 From: Mike Rapoport To: "Matthew Wilcox (Oracle)" Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Christoph Hellwig , Jeff Layton , "Kirill A . Shutemov" , Vlastimil Babka , William Kucharski , David Howells Subject: Re: [PATCH v14 026/138] mm/writeback: Add folio_wait_stable() Message-ID: References: <20210715033704.692967-1-willy@infradead.org> <20210715033704.692967-27-willy@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210715033704.692967-27-willy@infradead.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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) > Reviewed-by: Christoph Hellwig > Acked-by: Jeff Layton > Acked-by: Kirill A. Shutemov > Acked-by: Vlastimil Babka > Reviewed-by: William Kucharski > Reviewed-by: David Howells > --- > 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 > > -- Sincerely yours, Mike.