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, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 58BC4C433E6 for ; Thu, 28 Jan 2021 16:25:04 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D9C5D64DF2 for ; Thu, 28 Jan 2021 16:25:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D9C5D64DF2 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=l40l0SRupieGdo433lYL7m0Pnc3NRG/qcQDCn8Y0uzk=; b=v9nkK8Mqb/03RiK4RY2nQZeMm ay2xEuIevSXnV51cvqT4513TV5UT55zYbF6jXI54ruLYQCxLu3KQPOlouh39Ta3HlPvYBAbBtyJ8I QzUI53MumPQi8RBp4iMMt4qZ/MMJPLTY7v0nAUh0G2GePqDQxzZ+vgbXSNviewap9F3SE4ReIn3UH fIyIg6t3nm82q/lHrItZBRxAA3sFYuko0vWgigCNiIg/h+S99+jtbFrURoCVlU/Ag6ZICY3BJnbBi M4GJ/fK2OlUEiADcielFTGPiCgUvX6wJysqv2Le+3qTsCGX+t4kIfjc8dF8/kvYFNZUDOxnJmx2N9 evb7AQDnw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l5A5U-0004W6-Ju; Thu, 28 Jan 2021 16:24:04 +0000 Received: from mx2.suse.de ([195.135.220.15]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l5A5R-0004U1-Ga; Thu, 28 Jan 2021 16:24:02 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1611851039; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=WWmcYeElb62qutT0Kcoo6xDCdrj66eelF83EHgFDfB4=; b=ZJlUD8pQK2nIX/Cnj1UyvowYIjPxyyZKq5kI8NYKzxJt5tEqE9314CXd37wDkUTpPEa6Vf YEZQtVEmaZg8j88rldXEzhTt3tU4zmyFht8LR4yeM3dwIAsKI4509bn1BlnRgtEZNO+G8l DXrH4A5dU/j38+v0Vo5e/8cwta9YIu0= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id A6C7DAC41; Thu, 28 Jan 2021 16:23:59 +0000 (UTC) Date: Thu, 28 Jan 2021 17:23:58 +0100 From: Michal Hocko To: Christoph Lameter Subject: Re: [PATCH v16 07/11] secretmem: use PMD-size pages to amortize direct map fragmentation Message-ID: References: <20210121122723.3446-1-rppt@kernel.org> <20210121122723.3446-8-rppt@kernel.org> <20210126114657.GL827@dhcp22.suse.cz> <303f348d-e494-e386-d1f5-14505b5da254@redhat.com> <20210126120823.GM827@dhcp22.suse.cz> <20210128092259.GB242749@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210128_112401_829040_1E994066 X-CRM114-Status: GOOD ( 24.23 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , David Hildenbrand , Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, "H. Peter Anvin" , linux-riscv@lists.infradead.org, Shuah Khan , Thomas Gleixner , Elena Reshetova , linux-arch@vger.kernel.org, Tycho Andersen , linux-nvdimm@lists.01.org, Will Deacon , x86@kernel.org, Matthew Wilcox , Mike Rapoport , Ingo Molnar , Michael Kerrisk , Palmer Dabbelt , Arnd Bergmann , James Bottomley , Hagen Paul Pfeifer , Borislav Petkov , Alexander Viro , Andy Lutomirski , Paul Walmsley , "Kirill A. Shutemov" , Dan Williams , linux-arm-kernel@lists.infradead.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, Palmer Dabbelt , linux-fsdevel@vger.kernel.org, Shakeel Butt , Andrew Morton , Rick Edgecombe , Roman Gushchin , Mike Rapoport Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu 28-01-21 15:56:36, Cristopher Lameter wrote: > On Thu, 28 Jan 2021, Michal Hocko wrote: > > > > > If you kill the allocating process then yes, it would work, but your > > > > process might be the very last to be selected. > > > > > > OOMs are different if you have a "constrained allocation". In that case it > > > is the fault of the process who wanted memory with certain conditions. > > > That memory is not available. General memory is available though. In that > > > case the allocating process is killed. > > > > I do not see this implementation would do anything like that. Neither > > anything like that implemented in the oom killer. Constrained > > allocations (cpusets/memcg/mempolicy) only do restrict their selection > > to processes which belong to the same domain. So I am not really sure > > what you are referring to. The is only a global knob to _always_ kill > > the allocating process on OOM. > > Constrained allocations refer to allocations where the NUMA nodes are > restricted or something else does not allow the use of arbitrary memory. > The OOM killer changes its behavior. Yes as described in the above paragraph. > In the past we fell back to killing the calling process. Yeah, but this is no longer the case since 6f48d0ebd907a (more than 10 years ago. Anyway this is not really important because if you want to kill the allocating task because there is no chance the fault can succed then there is a SIGBUS as already mentioned. -- Michal Hocko SUSE Labs _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel