From patchwork Tue Dec 8 19:46:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthew Wilcox X-Patchwork-Id: 11959369 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=-16.6 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,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 245E6C433FE for ; Tue, 8 Dec 2020 19:47:08 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 94F5D23C17 for ; Tue, 8 Dec 2020 19:47:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 94F5D23C17 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 31A676B0068; Tue, 8 Dec 2020 14:47:03 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 252A56B0071; Tue, 8 Dec 2020 14:47:03 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E87F96B006E; Tue, 8 Dec 2020 14:47:02 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0151.hostedemail.com [216.40.44.151]) by kanga.kvack.org (Postfix) with ESMTP id CA1E76B0068 for ; Tue, 8 Dec 2020 14:47:02 -0500 (EST) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 954441EE6 for ; Tue, 8 Dec 2020 19:47:02 +0000 (UTC) X-FDA: 77571148284.08.fly71_500a82f273e9 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin08.hostedemail.com (Postfix) with ESMTP id 786EF1819E76F for ; Tue, 8 Dec 2020 19:47:02 +0000 (UTC) X-HE-Tag: fly71_500a82f273e9 X-Filterd-Recvd-Size: 4712 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf30.hostedemail.com (Postfix) with ESMTP for ; Tue, 8 Dec 2020 19:47:00 +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=uWCZnlKBNIoKAATMrB8Qjh7qh+SV4Lj3PLacia1sewI=; b=OptOLtv1sgOFbFuWJ83HzKZfnY kMoL3pehTIHoaKLhc6EJmKuyBzeR82PmS0IAaAq0tMLRc6GrAmpo6dIHr39h+EarleBhn6taoYEso UkxvEOnyGth1AynkMpX6IBzI9pK+ILS4eisHUoPxGA+3lfYRFQWi3b7SOpnBjuRf14F18NZ7QiMF7 sQNSsrhYxeleB/n7RnxS69qkoP5n86vMT42pZWgTgJP7yXpu4d+j945bOUiKOzPWI2Cf5KN6kVHAA FP6dgQhRu7vcrmLT5kkBw2RP9m4UTV5ZcHtuzKHK40I1OsU2BCBESxRPHpPySX6DKCwIs8Rvn9g0d 2MSSgMqg==; Received: from willy by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kmiws-00050d-OO; Tue, 08 Dec 2020 19:46:58 +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: [RFC PATCH 05/11] mm: Add unlock_folio Date: Tue, 8 Dec 2020 19:46:47 +0000 Message-Id: <20201208194653.19180-6-willy@infradead.org> X-Mailer: git-send-email 2.21.3 In-Reply-To: <20201208194653.19180-1-willy@infradead.org> References: <20201208194653.19180-1-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 doing a repeated compound_head() This shortens the function from 120 bytes to 76 bytes. 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 46d4b1704770..64ae1bb62765 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -588,7 +588,21 @@ 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); +extern void unlock_folio(struct folio *folio); + +/** + * 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 78090ee08ac2..de8372307b33 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1443,29 +1443,22 @@ 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_PAGE(!FolioLocked(folio), &folio->page); + 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); /** * end_page_writeback - end writeback against a page