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=-3.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 B9E99C433E0 for ; Fri, 26 Jun 2020 11:07:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 54523207E8 for ; Fri, 26 Jun 2020 11:07:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="RUL1JawB" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 54523207E8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 3A3B86B0007; Fri, 26 Jun 2020 07:07:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 3545D6B0008; Fri, 26 Jun 2020 07:07:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 21BDC6B0022; Fri, 26 Jun 2020 07:07:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0056.hostedemail.com [216.40.44.56]) by kanga.kvack.org (Postfix) with ESMTP id 073146B0007 for ; Fri, 26 Jun 2020 07:07:52 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 4488E180AD82F for ; Fri, 26 Jun 2020 11:07:51 +0000 (UTC) X-FDA: 76971087942.25.nerve61_601354026e54 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin25.hostedemail.com (Postfix) with ESMTP id 100BA1804E3A8 for ; Fri, 26 Jun 2020 11:07:51 +0000 (UTC) X-HE-Tag: nerve61_601354026e54 X-Filterd-Recvd-Size: 3008 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf06.hostedemail.com (Postfix) with ESMTP for ; Fri, 26 Jun 2020 11:07:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ePLLvn3g4STvMdY6WpJ5BftJMQVL6KUjzTUZoL0oc+M=; b=RUL1JawBO+l23qmfT02FPmoWAp tMzPzy2tHXhTaqOnBNg5PoGPK8XREfCJmYdDYFvM07zI8LwTH1D/O2z2q02Orb3dMyVbUDhAZeiQf l+6uG231lJ4rrYmo7LXFbc3/YiNwTnO/r2pXEmVkJKuu73pGDiyoFYBVI6qH1LKBFPIWU4y5HJado iAQWXtINr/7dHNys57uXxDXGeCqjgRMtNAHQ8qA05+a5dTbBkqpbwncx48E0nvWffbIjiacHr1Vhs 6DXBiG49zvHSYa5TSxffiERcgqTiNp6BzI8bpU0dAcJhHQvw8yIvOFSGDSg4rnJmoCCf9TyUl1sme tRaKkZ9g==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jomCi-0005mc-8q; Fri, 26 Jun 2020 11:07:34 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 7D7513007CD; Fri, 26 Jun 2020 13:07:31 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 69B8029C4228B; Fri, 26 Jun 2020 13:07:31 +0200 (CEST) Date: Fri, 26 Jun 2020 13:07:31 +0200 From: Peter Zijlstra To: Joerg Roedel Cc: x86@kernel.org, hpa@zytor.com, Dave Hansen , Andy Lutomirski , Andrew Morton , Steven Rostedt , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Joerg Roedel Subject: Re: [PATCH] x86/mm: Pre-allocate p4d/pud pages for vmalloc area Message-ID: <20200626110731.GC4817@hirez.programming.kicks-ass.net> References: <20200626093450.27741-1-joro@8bytes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200626093450.27741-1-joro@8bytes.org> X-Rspamd-Queue-Id: 100BA1804E3A8 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 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, Jun 26, 2020 at 11:34:50AM +0200, Joerg Roedel wrote: > From: Joerg Roedel > > Pre-allocate the page-table pages for the vmalloc area at the level > which needs synchronization on x86. This is P4D for 5-level and PUD > for 4-level paging. > > Doing this at boot makes sure all page-tables in the system have these > pages already and do not need to be synchronized at runtime. The > runtime synchronizatin takes the pgd_lock and iterates over all > page-tables in the system, so it can take quite long and is better > avoided. > > Signed-off-by: Joerg Roedel > --- Can't we now remove arch_sync_kernel_mappings() from this same file?