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=-4.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS autolearn=no 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 D52C5C433E0 for ; Tue, 11 Aug 2020 04:46:58 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8D24F20678 for ; Tue, 11 Aug 2020 04:46:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="rTuIjnTK" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8D24F20678 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id E97BB6B0006; Tue, 11 Aug 2020 00:46:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id E2C856B0007; Tue, 11 Aug 2020 00:46:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D10496B0008; Tue, 11 Aug 2020 00:46:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0127.hostedemail.com [216.40.44.127]) by kanga.kvack.org (Postfix) with ESMTP id B74DA6B0006 for ; Tue, 11 Aug 2020 00:46:57 -0400 (EDT) Received: from smtpin12.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 1C60A4DC1 for ; Tue, 11 Aug 2020 04:46:57 +0000 (UTC) X-FDA: 77137052874.12.beam39_2b0384426fe0 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin12.hostedemail.com (Postfix) with ESMTP id DCEC318012C0B for ; Tue, 11 Aug 2020 04:46:56 +0000 (UTC) X-HE-Tag: beam39_2b0384426fe0 X-Filterd-Recvd-Size: 2311 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf14.hostedemail.com (Postfix) with ESMTP for ; Tue, 11 Aug 2020 04:46:56 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8F08320678; Tue, 11 Aug 2020 04:46:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597121215; bh=t24nShwFET2trWtIqrU1VnKyob0Hvc9cmx3UGaw42iE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=rTuIjnTKN4Ltv6ftGLpdaLzgXNshWG17p5H/BDPIzz7yZ6/1Jl67m2FjwWr8E/NI2 qqC0HX65Hh5gtERS4VsqxIe10LAs2iMj/PTudq2rPP5pZS53tnc+3XVrc+CVZT+wgl cxOPRKXn//KhfvzfHzsmtUbM+8MTuEr5zP+bn4rg= Date: Mon, 10 Aug 2020 21:46:55 -0700 From: Andrew Morton To: "Aneesh Kumar K.V" Cc: linux-mm@kvack.org, Harish Sriram Subject: Re: [PATCH] mm/vunmap: Add cond_resched() in vunmap_pmd_range Message-Id: <20200810214655.a3f82fc8ccd671a392164a09@linux-foundation.org> In-Reply-To: <20200807075933.310240-1-aneesh.kumar@linux.ibm.com> References: <20200807075933.310240-1-aneesh.kumar@linux.ibm.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: DCEC318012C0B X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam04 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: On Fri, 7 Aug 2020 13:29:33 +0530 "Aneesh Kumar K.V" wrote: > Like zap_pte_range add cond_resched so that we can avoid softlockups as reported > below. On non-preemptible kernel with large I/O map region (like the one we get > when using persistent memory with sector mode), an unmap of the namespace can report > below softlockups. > > ... > > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -102,6 +102,8 @@ static void vunmap_pmd_range(pud_t *pud, unsigned long addr, unsigned long end, > if (pmd_none_or_clear_bad(pmd)) > continue; > vunmap_pte_range(pmd, addr, next, mask); > + > + cond_resched(); > } while (pmd++, addr = next, addr != end); > } That looks sane. I'll aim for merging it in 5.9-rc2ish, with a cc:stable, OK?