From patchwork Fri Apr 21 22:12:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 86511 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp1376074vqo; Fri, 21 Apr 2023 15:30:42 -0700 (PDT) X-Google-Smtp-Source: AKy350bqzq/dNTEbmWG5pEqNSKE3VKQhQkf/+7bMLX0bHPmU5W6S60UA+C8CqiNd8K7k5SfVM1Of X-Received: by 2002:a17:90a:6b43:b0:246:9517:30b6 with SMTP id x3-20020a17090a6b4300b00246951730b6mr12477190pjl.4.1682116241814; Fri, 21 Apr 2023 15:30:41 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1682116241; cv=none; d=google.com; s=arc-20160816; b=Ug6fEvT0K65fBEKaF3ZetsK90ANdppGgBsLAFdWRKNL7ikbnGMUUAj50qe7Y7ZT6Oz uBhIlzesMYUyRq6u/mIPlXKEfeuKl71DcmNa10klvTnV4wd0itm/CBKXc0/Zc+eEVyyD /+Mr48CZFsLFKI9ArnpsYe8hot1wZI6g4aExbLXQfs7Tshr+ovRW0eiVP/9mK6E1gt2F 5zxNwEc6T48qdgi9KglbJcBh0Ay50JpxXziK0NuSbR4B3O5mv4OxV/HzmmQ/IJ5Gg8cq EbGHnkfkt7fg2R4ikZth1Bth3pw6eVHB4Z1fPgs4cSc3svD09bSSOob7iIpyvl9TRRmI dfrA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=u/AkHMm2p+EP+a6U0DbEFYOuvSo1i83VDzuubdv1yU4=; b=0LhmNzN1P6hxMwVg3VY1d3eLnKQimnQzGaJWsK8mgl5RiVY2VY3nOiC0GrpevuZF8h JjKMjbyR0ooJu2VZpPmTsOin9SYfBO1M1ZHvB4aDd4R74y7IyFnlvvhfr8RXAFZ2pMWh RoBHYBp9S/+W+twhI5nCeYt4Baf7y/IRsqb92qHNMtQxoBVfNzEwB/B4rxaMYePOrl7K bQa+7k0/RRN+C1CJsHf6y/hOedyHGqNR/KEEzO4HUDcD4oNM5dB75WzFFsOhQO2FIVu2 5kEaZsgVmlGA43kfNP9duGqoqzpUC7iT6aH+3rBmJ52iOb1ZZZIcrTQw6Xskz9jcc6Zo 6CNg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b="gWPYUh/q"; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id mh14-20020a17090b4ace00b002476173727fsi8686629pjb.26.2023.04.21.15.30.28; Fri, 21 Apr 2023 15:30:41 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b="gWPYUh/q"; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233765AbjDUWN2 (ORCPT + 99 others); Fri, 21 Apr 2023 18:13:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51736 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233661AbjDUWNY (ORCPT ); Fri, 21 Apr 2023 18:13:24 -0400 Received: from mail-pf1-x42d.google.com (mail-pf1-x42d.google.com [IPv6:2607:f8b0:4864:20::42d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D4A47198B for ; Fri, 21 Apr 2023 15:13:22 -0700 (PDT) Received: by mail-pf1-x42d.google.com with SMTP id d2e1a72fcca58-63d4595d60fso17238593b3a.0 for ; Fri, 21 Apr 2023 15:13:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1682115202; x=1684707202; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=u/AkHMm2p+EP+a6U0DbEFYOuvSo1i83VDzuubdv1yU4=; b=gWPYUh/qJS3hKUZOK+9h4MWoL8QjpqBENZF1/R77mtm+LeEDasMRdSowMwEpPxxS78 EP2q9aDYBJHna1dXO/vRjzhgMH3xXjajRzj+Gem3tqcctYYdBwGqaQ29Kog5RyRfy0yp UjVmuXQ923zKnlvwr5/ZYrwLOML+t858ymiAc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1682115202; x=1684707202; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=u/AkHMm2p+EP+a6U0DbEFYOuvSo1i83VDzuubdv1yU4=; b=lWmzPLLu/PxABxqwhwajJkCOEjaCcViOUC0CRsffN2GAvsPZQLCCrPFAod7PvrsZWt pzormJHHoIgObT0c8m4KYzAr5uMt21RgsLQ3k47dJji4bZ1m1NdGVCYRJch4T8h9ps6q eR6erWPTUQuiwjxJVntxkaghKnTl0LnE7otybmZlR4SMsUTjYgFYkKNR5ZAm/6ijeoOE G4fIeW+939P/l6ESDgOpJ01talhySElp5yCa4Lz8PZcQB9/TduWOqU5YvF/lFCZCJSW9 II8NgMwsCJ9LE777DgKyq+ym0sA31RUl4QW/v/qtaLrzja/fmcnMp3Op+RReP/D6rC0F UfRw== X-Gm-Message-State: AAQBX9dmQatpdlUcfpn3jSjrt23QxhkBx3meXmX4+Xe2EJ0DByjuRDlS dS/231yHQZK45eTCkDkhdy7OAQ== X-Received: by 2002:a05:6a20:8426:b0:f0:8708:2341 with SMTP id c38-20020a056a20842600b000f087082341mr7837599pzd.26.1682115202268; Fri, 21 Apr 2023 15:13:22 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:9d:2:87cc:9018:e569:4a27]) by smtp.gmail.com with ESMTPSA id y72-20020a62644b000000b006372791d708sm3424715pfb.104.2023.04.21.15.13.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Apr 2023 15:13:21 -0700 (PDT) From: Douglas Anderson To: Andrew Morton , Mel Gorman , Vlastimil Babka , Ying , Alexander Viro , Christian Brauner Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Yu Zhao , linux-fsdevel@vger.kernel.org, Matthew Wilcox , Douglas Anderson Subject: [PATCH v2 1/4] mm/filemap: Add folio_lock_timeout() Date: Fri, 21 Apr 2023 15:12:45 -0700 Message-ID: <20230421151135.v2.1.I2b71e11264c5c214bc59744b9e13e4c353bc5714@changeid> X-Mailer: git-send-email 2.40.0.634.g4ca3ef3211-goog In-Reply-To: <20230421221249.1616168-1-dianders@chromium.org> References: <20230421221249.1616168-1-dianders@chromium.org> MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1763826720438041269?= X-GMAIL-MSGID: =?utf-8?q?1763826720438041269?= Add a variant of folio_lock() that can timeout. This is useful to avoid unbounded waits for the page lock in kcompactd. Signed-off-by: Douglas Anderson --- Changes in v2: - "Add folio_lock_timeout()" new for v2. include/linux/pagemap.h | 16 ++++++++++++++ mm/filemap.c | 47 +++++++++++++++++++++++++++++------------ 2 files changed, 50 insertions(+), 13 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 0acb8e1fb7af..0f3ef9f79300 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -892,6 +892,7 @@ static inline bool wake_page_match(struct wait_page_queue *wait_page, } void __folio_lock(struct folio *folio); +int __folio_lock_timeout(struct folio *folio, long timeout); int __folio_lock_killable(struct folio *folio); bool __folio_lock_or_retry(struct folio *folio, struct mm_struct *mm, unsigned int flags); @@ -952,6 +953,21 @@ static inline void folio_lock(struct folio *folio) __folio_lock(folio); } +/** + * folio_lock_timeout() - Lock this folio, with a timeout. + * @folio: The folio to lock. + * @timeout: The timeout in jiffies; %MAX_SCHEDULE_TIMEOUT means wait forever. + * + * Return: 0 upon success; -ETIMEDOUT upon failure. + */ +static inline int folio_lock_timeout(struct folio *folio, long timeout) +{ + might_sleep(); + if (!folio_trylock(folio)) + return __folio_lock_timeout(folio, timeout); + return 0; +} + /** * lock_page() - Lock the folio containing this page. * @page: The page to lock. diff --git a/mm/filemap.c b/mm/filemap.c index 2723104cc06a..c6056ec41284 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1220,7 +1220,7 @@ static inline bool folio_trylock_flag(struct folio *folio, int bit_nr, int sysctl_page_lock_unfairness = 5; static inline int folio_wait_bit_common(struct folio *folio, int bit_nr, - int state, enum behavior behavior) + int state, enum behavior behavior, long timeout) { wait_queue_head_t *q = folio_waitqueue(folio); int unfairness = sysctl_page_lock_unfairness; @@ -1229,6 +1229,7 @@ static inline int folio_wait_bit_common(struct folio *folio, int bit_nr, bool thrashing = false; unsigned long pflags; bool in_thrashing; + int err; if (bit_nr == PG_locked && !folio_test_uptodate(folio) && folio_test_workingset(folio)) { @@ -1295,10 +1296,13 @@ static inline int folio_wait_bit_common(struct folio *folio, int bit_nr, /* Loop until we've been woken or interrupted */ flags = smp_load_acquire(&wait->flags); if (!(flags & WQ_FLAG_WOKEN)) { + if (!timeout) + break; + if (signal_pending_state(state, current)) break; - io_schedule(); + timeout = io_schedule_timeout(timeout); continue; } @@ -1324,10 +1328,10 @@ static inline int folio_wait_bit_common(struct folio *folio, int bit_nr, } /* - * If a signal happened, this 'finish_wait()' may remove the last - * waiter from the wait-queues, but the folio waiters bit will remain - * set. That's ok. The next wakeup will take care of it, and trying - * to do it here would be difficult and prone to races. + * If a signal/timeout happened, this 'finish_wait()' may remove the + * last waiter from the wait-queues, but the folio waiters bit will + * remain set. That's ok. The next wakeup will take care of it, and + * trying to do it here would be difficult and prone to races. */ finish_wait(q, wait); @@ -1336,6 +1340,13 @@ static inline int folio_wait_bit_common(struct folio *folio, int bit_nr, psi_memstall_leave(&pflags); } + /* + * If we don't meet the success criteria below then we've got an error + * of some sort. Differentiate between the two error cases. If there's + * no time left it must have been a timeout. + */ + err = !timeout ? -ETIMEDOUT : -EINTR; + /* * NOTE! The wait->flags weren't stable until we've done the * 'finish_wait()', and we could have exited the loop above due @@ -1350,9 +1361,9 @@ static inline int folio_wait_bit_common(struct folio *folio, int bit_nr, * waiter, but an exclusive one requires WQ_FLAG_DONE. */ if (behavior == EXCLUSIVE) - return wait->flags & WQ_FLAG_DONE ? 0 : -EINTR; + return wait->flags & WQ_FLAG_DONE ? 0 : err; - return wait->flags & WQ_FLAG_WOKEN ? 0 : -EINTR; + return wait->flags & WQ_FLAG_WOKEN ? 0 : err; } #ifdef CONFIG_MIGRATION @@ -1442,13 +1453,15 @@ void migration_entry_wait_on_locked(swp_entry_t entry, pte_t *ptep, void folio_wait_bit(struct folio *folio, int bit_nr) { - folio_wait_bit_common(folio, bit_nr, TASK_UNINTERRUPTIBLE, SHARED); + folio_wait_bit_common(folio, bit_nr, TASK_UNINTERRUPTIBLE, SHARED, + MAX_SCHEDULE_TIMEOUT); } EXPORT_SYMBOL(folio_wait_bit); int folio_wait_bit_killable(struct folio *folio, int bit_nr) { - return folio_wait_bit_common(folio, bit_nr, TASK_KILLABLE, SHARED); + return folio_wait_bit_common(folio, bit_nr, TASK_KILLABLE, SHARED, + MAX_SCHEDULE_TIMEOUT); } EXPORT_SYMBOL(folio_wait_bit_killable); @@ -1467,7 +1480,8 @@ EXPORT_SYMBOL(folio_wait_bit_killable); */ static int folio_put_wait_locked(struct folio *folio, int state) { - return folio_wait_bit_common(folio, PG_locked, state, DROP); + return folio_wait_bit_common(folio, PG_locked, state, DROP, + MAX_SCHEDULE_TIMEOUT); } /** @@ -1662,17 +1676,24 @@ EXPORT_SYMBOL_GPL(page_endio); void __folio_lock(struct folio *folio) { folio_wait_bit_common(folio, PG_locked, TASK_UNINTERRUPTIBLE, - EXCLUSIVE); + EXCLUSIVE, MAX_SCHEDULE_TIMEOUT); } EXPORT_SYMBOL(__folio_lock); int __folio_lock_killable(struct folio *folio) { return folio_wait_bit_common(folio, PG_locked, TASK_KILLABLE, - EXCLUSIVE); + EXCLUSIVE, MAX_SCHEDULE_TIMEOUT); } EXPORT_SYMBOL_GPL(__folio_lock_killable); +int __folio_lock_timeout(struct folio *folio, long timeout) +{ + return folio_wait_bit_common(folio, PG_locked, TASK_KILLABLE, + EXCLUSIVE, timeout); +} +EXPORT_SYMBOL_GPL(__folio_lock_timeout); + static int __folio_lock_async(struct folio *folio, struct wait_page_queue *wait) { struct wait_queue_head *q = folio_waitqueue(folio);