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=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 067B4C4320A for ; Tue, 10 Aug 2021 16:08:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DBC55610E9 for ; Tue, 10 Aug 2021 16:08:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233102AbhHJQIf (ORCPT ); Tue, 10 Aug 2021 12:08:35 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:49908 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232734AbhHJQI0 (ORCPT ); Tue, 10 Aug 2021 12:08:26 -0400 Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id B404921FF3; Tue, 10 Aug 2021 16:08:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1628611683; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xYaFzcIMw3qFmrYTgphte6/1PHFhObKrzlRtTshtz30=; b=qk8q7pkuEJDBRmDi0XWjJiCMOBtUMgVD3VgPOsfacQ+7B0EzIvwE3AjBrQgr26JZBbr8HO UK7XZc74aeOTC/NpE8tXNfRwzQ90U04DGhk/vnycpDrYuX72GEFDabffdnhMT7c3ffEwNe JlmEc8SeRUlFPb78uk77QeBzLf91CTk= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1628611683; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xYaFzcIMw3qFmrYTgphte6/1PHFhObKrzlRtTshtz30=; b=/Rvwrz+U1xpku/2UomWswBRqPRzN8NIdIVSOHq1NPDYJpYLl5tCpTpX41ahErZY+hu1Mfd oNt2yf+ptmJzPGBw== Received: from imap1.suse-dmz.suse.de (imap1.suse-dmz.suse.de [192.168.254.73]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap1.suse-dmz.suse.de (Postfix) with ESMTPS id 8BB4C137DA; Tue, 10 Aug 2021 16:08:03 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap1.suse-dmz.suse.de with ESMTPSA id Kyr4IGOkEmHUTAAAGKfGzw (envelope-from ); Tue, 10 Aug 2021 16:08:03 +0000 Subject: Re: [PATCH v14 022/138] mm/filemap: Add __folio_lock_or_retry() To: "Matthew Wilcox (Oracle)" , linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, Christoph Hellwig , Jeff Layton , "Kirill A . Shutemov" , William Kucharski References: <20210715033704.692967-1-willy@infradead.org> <20210715033704.692967-23-willy@infradead.org> From: Vlastimil Babka Message-ID: <984ee3c0-7189-3481-8a1f-9e2765906224@suse.cz> Date: Tue, 10 Aug 2021 18:08:03 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.12.0 MIME-Version: 1.0 In-Reply-To: <20210715033704.692967-23-willy@infradead.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/15/21 5:35 AM, Matthew Wilcox (Oracle) wrote: > Convert __lock_page_or_retry() to __folio_lock_or_retry(). This actually > saves 4 bytes in the only caller of lock_page_or_retry() (due to better > register allocation) and saves the 14 byte cost of calling page_folio() > in __folio_lock_or_retry() for a total saving of 18 bytes. Also use > a bool for the return type. > > Signed-off-by: Matthew Wilcox (Oracle) > Reviewed-by: Christoph Hellwig > Acked-by: Jeff Layton > Acked-by: Kirill A. Shutemov > Reviewed-by: William Kucharski Acked-by: Vlastimil Babka Nit: > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -1625,48 +1625,46 @@ static int __folio_lock_async(struct folio *folio, struct wait_page_queue *wait) > > /* > * Return values: > - * 1 - page is locked; mmap_lock is still held. > - * 0 - page is not locked. > + * true - folio is locked; mmap_lock is still held. > + * false - folio is not locked. > * mmap_lock has been released (mmap_read_unlock(), unless flags had both > * FAULT_FLAG_ALLOW_RETRY and FAULT_FLAG_RETRY_NOWAIT set, in > * which case mmap_lock is still held. > * > * If neither ALLOW_RETRY nor KILLABLE are set, will always return 1 s/1/true/ ? :) > - * with the page locked and the mmap_lock unperturbed. > + * with the folio locked and the mmap_lock unperturbed. > */ > -int __lock_page_or_retry(struct page *page, struct mm_struct *mm, > +bool __folio_lock_or_retry(struct folio *folio, struct mm_struct *mm, > unsigned int flags) > { > - struct folio *folio = page_folio(page); > - > if (fault_flag_allow_retry_first(flags)) { > /* > * CAUTION! In this case, mmap_lock is not released > * even though return 0. > */ > if (flags & FAULT_FLAG_RETRY_NOWAIT) > - return 0; > + return false; > > mmap_read_unlock(mm); > if (flags & FAULT_FLAG_KILLABLE) > folio_wait_locked_killable(folio); > else > folio_wait_locked(folio); > - return 0; > + return false; > } > if (flags & FAULT_FLAG_KILLABLE) { > - int ret; > + bool ret; > > ret = __folio_lock_killable(folio); > if (ret) { > mmap_read_unlock(mm); > - return 0; > + return false; > } > } else { > __folio_lock(folio); > } > > - return 1; > + return true; > } > > /**