From patchwork Thu Jan 28 07:03:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 12052073 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=-16.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 94DE1C433E0 for ; Thu, 28 Jan 2021 07:04:45 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1A13664DD6 for ; Thu, 28 Jan 2021 07:04:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A13664DD6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 11C836B0080; Thu, 28 Jan 2021 02:04:34 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 07DD96B0081; Thu, 28 Jan 2021 02:04:34 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E8A206B0082; Thu, 28 Jan 2021 02:04:33 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0068.hostedemail.com [216.40.44.68]) by kanga.kvack.org (Postfix) with ESMTP id CCD906B0080 for ; Thu, 28 Jan 2021 02:04:33 -0500 (EST) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 9B422181AEF1F for ; Thu, 28 Jan 2021 07:04:33 +0000 (UTC) X-FDA: 77754295626.23.bomb11_1e12ab22759d Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin23.hostedemail.com (Postfix) with ESMTP id 80AFF37606 for ; Thu, 28 Jan 2021 07:04:33 +0000 (UTC) X-HE-Tag: bomb11_1e12ab22759d X-Filterd-Recvd-Size: 4936 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf42.hostedemail.com (Postfix) with ESMTP for ; Thu, 28 Jan 2021 07:04:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:MIME-Version: References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=9oVIcCkUXd+sZVNIsuy1+nfatx2hPStEQuhz4k/iTZ8=; b=Kv2Gm2DZYgduSqaqVAyqxVHzml /onl1b27i5NHeHBX1w4RDTXCftiD5GUAt14eJzT3Yil50i45rlZ+2WcxwDAxC9ANRPVCkHdV+VcEX VN0oK7IhrponProZDAd/n6YEpU5v8XMOUCh1uGyzgX6I2kCp3ao8rS5qtV6qL/fGiN77uQkAkX27H 4HIcm/WjGMVHsOYOdlzFYNKIyBRg0yZKlFQ8qqI1/yRCWjs2XllU/HK55z4qT9lkVoJWfRFzPoYcK c48uFejfuCA0db6YB1jXBJCVLLbWXhuMkaLpesWdCNkb9LcxM4MdSrhValF7BQMlBmK70HAW9Z262 kwJrPCSA==; Received: from willy by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1l51Lw-00847s-18; Thu, 28 Jan 2021 07:04:28 +0000 From: "Matthew Wilcox (Oracle)" To: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Cc: "Matthew Wilcox (Oracle)" , linux-kernel@vger.kernel.org Subject: [PATCH v3 13/25] mm: Add unlock_folio Date: Thu, 28 Jan 2021 07:03:52 +0000 Message-Id: <20210128070404.1922318-14-willy@infradead.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210128070404.1922318-1-willy@infradead.org> References: <20210128070404.1922318-1-willy@infradead.org> MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Convert unlock_page() to call unlock_folio(). By using a folio we avoid a call to compound_head(). This shortens the function from 39 bytes to 25 and removes 4 instructions on x86-64. Those instructions are currently pushed into each caller, but subsequent patches will convert many of the callers to operate on folios. Signed-off-by: Matthew Wilcox (Oracle) --- include/linux/pagemap.h | 16 +++++++++++++++- mm/filemap.c | 27 ++++++++++----------------- 2 files changed, 25 insertions(+), 18 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 86956e97cd5e..5fcab5e1787c 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -623,9 +623,23 @@ extern int __lock_page_killable(struct page *page); extern int __lock_page_async(struct page *page, struct wait_page_queue *wait); extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm, unsigned int flags); -extern void unlock_page(struct page *page); +void unlock_folio(struct folio *folio); extern void unlock_page_fscache(struct page *page); +/** + * unlock_page - Unlock a locked page. + * @page: The page. + * + * Unlocks the page and wakes up any thread sleeping on the page lock. + * + * Context: May be called from interrupt or process context. May not be + * called from NMI context. + */ +static inline void unlock_page(struct page *page) +{ + return unlock_folio(page_folio(page)); +} + /* * Return true if the page was successfully locked */ diff --git a/mm/filemap.c b/mm/filemap.c index 4417fd15d633..b639651d1573 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1407,29 +1407,22 @@ static inline bool clear_bit_unlock_is_negative_byte(long nr, volatile void *mem #endif /** - * unlock_page - unlock a locked page - * @page: the page + * unlock_folio - Unlock a locked folio. + * @folio: The folio. * - * Unlocks the page and wakes up sleepers in wait_on_page_locked(). - * Also wakes sleepers in wait_on_page_writeback() because the wakeup - * mechanism between PageLocked pages and PageWriteback pages is shared. - * But that's OK - sleepers in wait_on_page_writeback() just go back to sleep. + * Unlocks the folio and wakes up any thread sleeping on the page lock. * - * Note that this depends on PG_waiters being the sign bit in the byte - * that contains PG_locked - thus the BUILD_BUG_ON(). That allows us to - * clear the PG_locked bit and test PG_waiters at the same time fairly - * portably (architectures that do LL/SC can test any bit, while x86 can - * test the sign bit). + * Context: May be called from interrupt or process context. May not be + * called from NMI context. */ -void unlock_page(struct page *page) +void unlock_folio(struct folio *folio) { BUILD_BUG_ON(PG_waiters != 7); - page = compound_head(page); - VM_BUG_ON_PAGE(!PageLocked(page), page); - if (clear_bit_unlock_is_negative_byte(PG_locked, &page->flags)) - wake_up_page_bit(page, PG_locked); + VM_BUG_ON_FOLIO(!FolioLocked(folio), folio); + if (clear_bit_unlock_is_negative_byte(PG_locked, folio_flags(folio))) + wake_up_page_bit(&folio->page, PG_locked); } -EXPORT_SYMBOL(unlock_page); +EXPORT_SYMBOL(unlock_folio); /** * unlock_page_fscache - Unlock a page pinned with PG_fscache