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=-0.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,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 93D37C433DF for ; Fri, 12 Jun 2020 15:19:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F397220838 for ; Fri, 12 Jun 2020 15:19:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=pobox.com header.i=@pobox.com header.b="ch+G5Ff+"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=fluxnic.net header.i=@fluxnic.net header.b="v5jS8qjx" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F397220838 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=fluxnic.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 640EB8D00C5; Fri, 12 Jun 2020 11:19:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5CA3D8D00A0; Fri, 12 Jun 2020 11:19:32 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 492598D00C5; Fri, 12 Jun 2020 11:19:32 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0158.hostedemail.com [216.40.44.158]) by kanga.kvack.org (Postfix) with ESMTP id 2DDCE8D00A0 for ; Fri, 12 Jun 2020 11:19:32 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id D7494181ABE8A for ; Fri, 12 Jun 2020 15:19:31 +0000 (UTC) X-FDA: 76920918942.14.beds06_19119af26ddd Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin14.hostedemail.com (Postfix) with ESMTP id A15221810E011 for ; Fri, 12 Jun 2020 15:19:31 +0000 (UTC) X-HE-Tag: beds06_19119af26ddd X-Filterd-Recvd-Size: 3201 Received: from pb-smtp20.pobox.com (pb-smtp20.pobox.com [173.228.157.52]) by imf14.hostedemail.com (Postfix) with ESMTP for ; Fri, 12 Jun 2020 15:19:31 +0000 (UTC) Received: from pb-smtp20.pobox.com (unknown [127.0.0.1]) by pb-smtp20.pobox.com (Postfix) with ESMTP id 1ED59E4CC8; Fri, 12 Jun 2020 11:19:30 -0400 (EDT) (envelope-from nico@fluxnic.net) DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=pobox.com; h=date:from:to :cc:subject:in-reply-to:message-id:references:mime-version :content-type; s=sasl; bh=22t9Ut8LGNPQZcuwBoygY9sFDBQ=; b=ch+G5F f+rL9Y26JkM0TLDTfVupXzFMDulMjp1sMBUdGKFMmjp1modPgIygeyoZTyVOuRw+ fAuBoAQA+HW7pEcZbxOFf4Dghu2GwFStiVqRRRR3Q8O6UK3MSddf8ZTSVi45wdPK /tknsJa6jpntcZs4/0B54vnBDPDs0lG8k5Qso= Received: from pb-smtp20.sea.icgroup.com (unknown [127.0.0.1]) by pb-smtp20.pobox.com (Postfix) with ESMTP id 1609AE4CC7; Fri, 12 Jun 2020 11:19:30 -0400 (EDT) (envelope-from nico@fluxnic.net) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed; d=fluxnic.net; h=date:from:to:cc:subject:in-reply-to:message-id:references:mime-version:content-type; s=2016-12.pbsmtp; bh=+j2zvxY3yyACYmz62lMN5mkK3euzNoR2JXP7LPUWCaA=; b=v5jS8qjxtE91zh+Qiqg4lLx/8UpHSwhsar4xdmNNdFLRGtCwuesR9hp4v2lgfr+ll9ZTtCwf8AN6/HgHuXA2zK9L8ITkZ6F2455mW1BwgExJK+QV1xJsoYm/cGlhr4iSM6jEV/K36ENBr7MQ3cqJMoLFd3dgAtYHEZXMvAR3AN4= Received: from yoda.home (unknown [24.203.50.76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by pb-smtp20.pobox.com (Postfix) with ESMTPSA id DCCC5E4CC3; Fri, 12 Jun 2020 11:19:25 -0400 (EDT) (envelope-from nico@fluxnic.net) Received: from xanadu.home (xanadu.home [192.168.2.2]) by yoda.home (Postfix) with ESMTPSA id 011CC2DA0AF0; Fri, 12 Jun 2020 11:19:23 -0400 (EDT) Date: Fri, 12 Jun 2020 11:19:23 -0400 (EDT) From: Nicolas Pitre To: afzal mohammed cc: Russell King - ARM Linux admin , Arnd Bergmann , Linus Walleij , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, Catalin Marinas , Will Deacon Subject: Re: [RFC 0/3] ARM: copy_{from,to}_user() for vmsplit 4g/4g In-Reply-To: Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-Pobox-Relay-ID: 1A10A78E-ACC0-11EA-AF12-B0405B776F7B-78420484!pb-smtp20.pobox.com X-Rspamd-Queue-Id: A15221810E011 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, 12 Jun 2020, afzal mohammed wrote: > Performance wise, results are not encouraging, 'dd' on tmpfs results, > > ARM Cortex-A8, BeagleBone White (256MiB RAM): > w/o series - ~29.5 MB/s > w/ series - ~20.5 MB/s > w/ series & highmem disabled - ~21.2 MB/s > > On Cortex-A15(2GiB RAM) in QEMU: > w/o series - ~4 MB/s > w/ series - ~2.6 MB/s > > Roughly a one-third drop in performance. Disabling highmem improves > performance only slightly. Could you compare with CONFIG_UACCESS_WITH_MEMCPY as well? Nicolas