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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A0A49C6FD18 for ; Sat, 22 Apr 2023 05:19:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 115DF6B0071; Sat, 22 Apr 2023 01:19:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0C53C6B0072; Sat, 22 Apr 2023 01:19:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EF6236B0074; Sat, 22 Apr 2023 01:19:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id E39FF6B0071 for ; Sat, 22 Apr 2023 01:19:17 -0400 (EDT) Received: from smtpin21.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 270EA1C6C8F for ; Sat, 22 Apr 2023 05:19:17 +0000 (UTC) X-FDA: 80707873554.21.747CF2E Received: from mail3-166.sinamail.sina.com.cn (mail3-166.sinamail.sina.com.cn [202.108.3.166]) by imf19.hostedemail.com (Postfix) with ESMTP id C75061A0004 for ; Sat, 22 Apr 2023 05:19:13 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=none; spf=pass (imf19.hostedemail.com: domain of hdanton@sina.com designates 202.108.3.166 as permitted sender) smtp.mailfrom=hdanton@sina.com; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1682140755; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WChN+yG2OXm6k2L5HlL4lBItTFpuPmkgg8pi65edWco=; b=KGSITNoIj20p6I/h1NZpeATL1baJAYDOYFskjc+M5rZtKV4cY3ZBhnXiefMi/XkkGQtg9b KmPFlk9VY08ihmYW5VmGw46bATV5+bINA3RzgBkND7Yv5ni5KU19GlXfeYXhCBPDe+hFMc 5sm+ID6TLudwbddq+vejoJ4yje40h/k= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1682140755; a=rsa-sha256; cv=none; b=yt/I7UucIpsUYCphz3j8au4m6Kd4qtgsh+yRcsuqrzAqJXsa+B/qNwN/OkaYuCxo6x5MI8 FrdA2FWl/fgNi2UjGo8D8LBqzJGQyvhwj236oIIvyWZAFQ379FIKepSeXgn0oQ/VqOELZE 3aMTJbDJ2b85wYTHu9RoPLCfzbUEcUc= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=none; spf=pass (imf19.hostedemail.com: domain of hdanton@sina.com designates 202.108.3.166 as permitted sender) smtp.mailfrom=hdanton@sina.com; dmarc=none X-SMAIL-HELO: localhost.localdomain Received: from unknown (HELO localhost.localdomain)([114.249.59.75]) by sina.com (172.16.97.23) with ESMTP id 64436E4C0001B4FA; Sat, 22 Apr 2023 13:19:09 +0800 (CST) X-Sender: hdanton@sina.com X-Auth-ID: hdanton@sina.com X-SMAIL-MID: 92781531457791 From: Hillf Danton To: Douglas Anderson Cc: Andrew Morton , Mel Gorman , Alexander Viro , Christian Brauner , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Yu Zhao , Matthew Wilcox Subject: Re: [PATCH v2 1/4] mm/filemap: Add folio_lock_timeout() Date: Sat, 22 Apr 2023 13:18:58 +0800 Message-Id: <20230422051858.1696-1-hdanton@sina.com> In-Reply-To: <20230421151135.v2.1.I2b71e11264c5c214bc59744b9e13e4c353bc5714@changeid> References: <20230421221249.1616168-1-dianders@chromium.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Rspamd-Queue-Id: C75061A0004 X-Rspamd-Server: rspam09 X-Stat-Signature: 4yubjmm1ey533yysxsgch8py7qkjbgct X-HE-Tag: 1682140753-390047 X-HE-Meta: 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 aXW/34Ps Gdjxi9nhQs7bHTmqKJfhR/ZiGd8Lw33RCO4G38n9D5vct04ENgfKt58wkTMs9yKXA7A9LmjQgglEh7b+EOfDaKxqPqX5D3rD/5Y0s6mAszXVA6P/51t4ZmACiRwaCfM/O9CcWo5iOc/qU1aA5tbTqqQg9C3krrY6ATmk/nv10yeOkvC74h6XphOgt+Q== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000020, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 21 Apr 2023 15:12:45 -0700 Douglas Anderson > Add a variant of folio_lock() that can timeout. This is useful to > avoid unbounded waits for the page lock in kcompactd. Given no mutex_lock_timeout() (perhaps because timeout makes no sense for spinlock), I suspect your fix lies in the right layer. If waiting for page under IO causes trouble for you, another simpler option is make IO faster (perhaps all you can do) for instance. If kcompactd is waken up by kswapd, waiting for slow IO is the right thing to do.