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 825E3C52D7D for ; Fri, 16 Aug 2024 05:17:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 102B48D0047; Fri, 16 Aug 2024 01:17:13 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0B0438D002B; Fri, 16 Aug 2024 01:17:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EB9608D0047; Fri, 16 Aug 2024 01:17:12 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id CEF058D002B for ; Fri, 16 Aug 2024 01:17:12 -0400 (EDT) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id 6F48CA0EC6 for ; Fri, 16 Aug 2024 05:17:12 +0000 (UTC) X-FDA: 82456949904.18.548B967 Received: from out30-97.freemail.mail.aliyun.com (out30-97.freemail.mail.aliyun.com [115.124.30.97]) by imf27.hostedemail.com (Postfix) with ESMTP id 5DF3C40013 for ; Fri, 16 Aug 2024 05:17:10 +0000 (UTC) Authentication-Results: imf27.hostedemail.com; dkim=pass header.d=linux.alibaba.com header.s=default header.b=aDTJbUp5; spf=pass (imf27.hostedemail.com: domain of hsiangkao@linux.alibaba.com designates 115.124.30.97 as permitted sender) smtp.mailfrom=hsiangkao@linux.alibaba.com; dmarc=pass (policy=none) header.from=linux.alibaba.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1723785394; 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-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=MIt4+z4yVxnBi0/X+/xarmiTleVh8KRAyG6uQFIHiP4=; b=cSk4JSQlMXwy0J964pGmM3ox2Cacymb6j6ybxdZ+A6AZf9Zlpk7ZeZCedBF/rJ+TzdOcuf LEAYpGFlaOxE4gw2vdKY4SYh4e4dJCWIHaEWNj9d5ORwrBB1VnzbX4rAciBpWTnTkDPpPz EmAalT6AzxOuMsBjwn9hvlL4JhQCDBo= ARC-Authentication-Results: i=1; imf27.hostedemail.com; dkim=pass header.d=linux.alibaba.com header.s=default header.b=aDTJbUp5; spf=pass (imf27.hostedemail.com: domain of hsiangkao@linux.alibaba.com designates 115.124.30.97 as permitted sender) smtp.mailfrom=hsiangkao@linux.alibaba.com; dmarc=pass (policy=none) header.from=linux.alibaba.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1723785394; a=rsa-sha256; cv=none; b=2yvFS+w0ZZCXQ2shsuXAcutNBqDVfYdczCoXQpTMT8SNWU5si2YucAcsyvD8zBPwbUYTTI G5IK+9AW0pWk4YcTG486H7+Sj0AHeIDKDCFjG3bti6gpcW7YBwm3Hi85DOF3WOlsWJgJ98 ky6fIfcO+7vJ3+AzbaNE376xGNdGDzI= DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1723785427; h=Message-ID:Date:MIME-Version:Subject:From:To:Content-Type; bh=MIt4+z4yVxnBi0/X+/xarmiTleVh8KRAyG6uQFIHiP4=; b=aDTJbUp53B4Fw7VBXtbBgBcqM2WhACZ2Tw4O0OydqlH8Lm6Un/7Ezw7X2SGq3LJUCOKzzhMe7QyvfmuLW9LBW7lVCkDhdFX0Ww0ew6pEijf+F/sKEsLNHk0clm3dYh917m2436jyu/T66T4hi2uMriwwEIWeIv6KlZ3OCBCjeOM= Received: from 30.221.129.229(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0WCzBcHy_1723785425) by smtp.aliyun-inc.com; Fri, 16 Aug 2024 13:17:06 +0800 Message-ID: Date: Fri, 16 Aug 2024 13:17:04 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] mm/migrate: fix deadlock in migrate_pages_batch() on large folios From: Gao Xiang To: Andrew Morton Cc: "Huang, Ying" , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Gao Xiang References: <20240728154913.4023977-1-hsiangkao@linux.alibaba.com> <87plqx0yh2.fsf@yhuang6-desk2.ccr.corp.intel.com> <20240815220224.d7970835d5c12b4833bd04dc@linux-foundation.org> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam03 X-Rspam-User: X-Rspamd-Queue-Id: 5DF3C40013 X-Stat-Signature: mqyw1fgh9r8y5yw9jhiawziy5ia8hijn X-HE-Tag: 1723785430-912162 X-HE-Meta: U2FsdGVkX19FmB4D24BGHZt8UeJI6gDrVMDHvnSpH5ZPV+3FCDTOQpDal1ZOx2JBNUAm/Is7Dmh7Efg7Z/x89PSM4XcY8n/tJWWY07bUBEA/jGfUvclBv7FlcpEOmExhRzgczvBZ+rinB2IkxqgeSTiG4wOVtvC4+PFd1c1tjr2j4zsYVixd3tgBTvHRQLPHVxAQvVTtYLMBuLBmE62qQ5bO25GvQek/XCkYV6qbSCXlCmoGJgNAZ3dzcZrRsdZkJV93ZB+ufBIVeZLV4yJP1rzrPtZ6PcaGDcZ1AlP6kdSWioMcJdksjE/V0Fa+zERPbaBUrKQa/04Wqk0awBj7E3v8Eoljrph63vxnc1l8iNgCqZqApiZNtoFv6E27uevp8oIY8o/Azgs/I76UYbHXoLIy3Jr+G73PYXhnpxsmuy7JsBsA7OLlhRy3whBBQUGagDUPU8QrbggGsHdA6E4Azf0wT1h+6XeMBP8mmJXd4rf9PFL3UVr2+y/EPIOw7tS1nVOkb70WdS59i8Isty+vPLcaqjl6K+brlzTU3Kx5q+yKfEmiIibVXwCRnguszZ6uxhbCkqdjupzhiU09ZulAOfCNwfr4AmIK5bpfSihwJJijh0wJexVsxd6wKWhgfqqH/Fi9556wwdKWkGIwqaN+qatZGQB7wanb9J83g66ZmWbfxeJ4Gh8dVRPyn0bsNcbcQa9TNYg0QIJMD1vEd4KwnytMwMCO/k2wBQj74Wq/9iLQsAIsf3puZMI0xPgTEVHiVT2Zi6tx6RHjlW/kPXM1XzM98zpRfp6S0Jn2F8uuWZAoetq24b9xxOSxA9pOJ8a4p4EaDrwyoBwSv92DHrw2HdDA4hLjzGcj3TKG3PcbTg1LY0+9W63CbFyatX23eZlxpPR4TGVquAhJlbhTsYM2c2b42vX3mqzuoWXTUDYWj6DuEgO5kZhFlEp3vxxQIXwblD2Gzktr+6DQkUtph4g 12mYbzbM vGTMca1utDUQVrKO76rgmTKPRF8le+yew3Z/vDJLMRJ0SnKilwp4Jma7kDTEXDG5WRnAjOxuKOtHq9+LtuSlL0lNCVQqFJ4sNlA6z1nBHXFs17o+5N3/VQ0K2eJ1kOLqNWIHhpRMGdjwpoc798QkJX2PAf9qFf1htxzerh+piw0p3bp6aVF0bnwooC1RqgX+P9wZR9bchivuQ16TjSEr05aQNc4XNd7V6qFS8DXnA9emFeBosc//RAFVdw3hVftlc+hIRpy7CeA0lVPM44ImgNYkOAbJxuSoxjgJwMOH51Lcz7NzrHkJwH2gtSl6TpXc0iQtTZc9x3XYS7EPdjvEWLNZfXibQN7cSke50ug4AzM0AN06CzUtR8DTG89hQ6gHYc1i8N0j9V5+/4eSItPsywnzXNN5nH9bnZbbRgajuX6BQ1QU= 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: List-Subscribe: List-Unsubscribe: On 2024/8/16 13:12, Gao Xiang wrote: > > Hi Andrew, > > On 2024/8/16 13:02, Andrew Morton wrote: >> On Mon, 29 Jul 2024 09:58:02 +0800 Gao Xiang wrote: >> >>>> For the fix, I think that we should still respect migrate_mode because >>>> users may prefer migration success over blocking. >>>> >>>> @@ -1492,11 +1492,17 @@ static int unmap_and_move_huge_page(new_folio_t get_new_folio, >>>>        return rc; >>>>    } >>>> -static inline int try_split_folio(struct folio *folio, struct list_head *split_folios) >>>> +static inline int try_split_folio(struct folio *folio, struct list_head *split_folios, >>>> +                  enum migrate_mode mode) >>>>    { >>>>        int rc; >>>> -    folio_lock(folio); >>>> +    if (mode == MIGRATE_ASYNC) { >>>> +        if (!folio_trylock(folio)) >>>> +            return -EAGAIN; >>>> +    } else { >>>> +        folio_lock(folio); >>>> +    } >>>>        rc = split_folio_to_list(folio, split_folios); >>>>        folio_unlock(folio); >>>>        if (!rc) >>> >>> Okay, yeah it looks better since it seems I missed the fallback >>> part in migrate_pages_sync(). >>> >>> Let me send the next version to follow your advice, thanks. >> >> The author seems to have disappeared.  Should we merge this as-is or >> does someone want to take a look at developing a v2? > > I've replied your email last week, I'm not sure why it has not > been addressed? > > https://lore.kernel.org/linux-mm/20240729021306.398286-1-hsiangkao@linux.alibaba.com/ > > The patch in your queue is already v2? No? Really confused about this, since the comment above was about v1. and v2 is already sent (in July 29) and in -next for two weeks with Reviewed-by: "Huang, Ying" Acked-by: David Hildenbrand What else I need to do to resolve this already resolved comment so that I could enable large folios without deadlocks anymore? Thanks, Gao Xiang > > Thanks, > Gao Xiang