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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, 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 BB356C433E1 for ; Thu, 13 Aug 2020 22:21:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 6A55620768 for ; Thu, 13 Aug 2020 22:21:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="FDc3lnf8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6A55620768 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id CCC266B0026; Thu, 13 Aug 2020 18:21:19 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id C7DE66B0027; Thu, 13 Aug 2020 18:21:19 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BBB0C6B0028; Thu, 13 Aug 2020 18:21:19 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0149.hostedemail.com [216.40.44.149]) by kanga.kvack.org (Postfix) with ESMTP id A4BE16B0026 for ; Thu, 13 Aug 2020 18:21:19 -0400 (EDT) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 6A45B52C3 for ; Thu, 13 Aug 2020 22:21:19 +0000 (UTC) X-FDA: 77146967478.08.sink33_2f16cbd26ff7 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin08.hostedemail.com (Postfix) with ESMTP id 2B5341819E626 for ; Thu, 13 Aug 2020 22:21:19 +0000 (UTC) X-HE-Tag: sink33_2f16cbd26ff7 X-Filterd-Recvd-Size: 2922 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf39.hostedemail.com (Postfix) with ESMTP for ; Thu, 13 Aug 2020 22:21:18 +0000 (UTC) Received: from kernel.org (unknown [87.70.91.42]) (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 472A2205CB; Thu, 13 Aug 2020 22:21:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597357277; bh=vs8lJM0eKVG8946mLVhSWB3Q/20CNgAkEixAfgafkMc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=FDc3lnf8lOFLTrY5pc7ZQGrj1KIKJs236WNcPF2mT821/WHgYyhu/zGUtxpK5cvpB cOEXrbfJPmQ3aJL/v72534XZ9CdHsIbKPMj64V522NBhGi3zP9gWllEa+r0+H3W9Yo As+2sFdoxOm9en+mCav8U+hx019LXy7LqQTz7j7s= Date: Fri, 14 Aug 2020 01:21:10 +0300 From: Mike Rapoport To: Matthew Wilcox Cc: Jessica Clarke , John Paul Adrian Glaubitz , Tony Luck , linux-ia64@vger.kernel.org, Anatoly Pugachev , Sergei Trofimovich , linux-mm@kvack.org, Frank Scheiner , Mike Rapoport Subject: Re: [PATCH v5] arch/ia64: Restore arch-specific pgd_offset_k implementation Message-ID: <20200813222110.GE752365@kernel.org> References: <20200813205521.5405-1-rppt@kernel.org> <20200813213631.GQ17456@casper.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200813213631.GQ17456@casper.infradead.org> X-Rspamd-Queue-Id: 2B5341819E626 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam02 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 Thu, Aug 13, 2020 at 10:36:31PM +0100, Matthew Wilcox wrote: > On Thu, Aug 13, 2020 at 11:55:21PM +0300, Mike Rapoport wrote: > > +/* > > + * In the kernel's mapped region we know everything is in region number 5, so > > + * as an optimisation its PGD already points to the area for that region. > > Is it actually an optimisation? Are there any benchmarks where this > makes any difference whatsoever? Or should the comment be closer to > > /* ia64 is gratuitously different. Cope with it. */ It better suits arch/ia64/Kconfig ;-) diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index 5b4ec80bf586..205cdb91a6d5 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -62,6 +62,7 @@ config IA64 the 32-bit X86 line. The IA-64 Linux project has a home page at and a mailing list at . + IA-64 is gratuitously different. Cope with it. > I might suggest that pgd be changed to be the same as every other pgd > in the system, and every other architecture. I did some grepping and got lost in IA-64 assembly, so I agree with Jessica that it would open a can of worms. -- Sincerely yours, Mike.