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=-6.7 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,USER_AGENT_SANE_1 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 C52AEC07E9B for ; Mon, 19 Jul 2021 14:25:24 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 8026E600CC for ; Mon, 19 Jul 2021 14:25:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8026E600CC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=roeck-us.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:Subject: From:References:To:Reply-To:Cc:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=KFgoS8rGDA8jlNut429oDmqgpP1c89EAw0zjhqb35QM=; b=Cl/Ru2sa1UxSpuvIqRGo+EF+6O HzHZw1DAM78NS+kY8i0lsclKtjWG5E8zr8uCHchYF58gcXtmP9Ud4UyVlPqUF88l7vDuMne2r2qvQ p//XgK8YDgZf6zFDJKh8BDXAHoic99TgjQEg5u2iTVG73NS3K7v29/dM+x/bY/agBM/G7/AgrUpLT EhR37cGV484a4aHt90CPzOkwgAnXE6OL/2YdqUn3xU5WcH8N/FQ303QCegH5rRlH/8DWhSLevcayb JYM3tJ+5nqoCFy4L/fCwXZLegKp7C/vYBm7GKkvLj96jSAvJ1l8l+DroqUjQOkPS61aZtCuEgC4Jw GBZVioSA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1m5UCj-009rzC-M7; Mon, 19 Jul 2021 14:25:09 +0000 Received: from mail-ot1-x329.google.com ([2607:f8b0:4864:20::329]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1m5UCP-009rrl-0W for linux-riscv@lists.infradead.org; Mon, 19 Jul 2021 14:24:50 +0000 Received: by mail-ot1-x329.google.com with SMTP id h24-20020a9d64180000b029036edcf8f9a6so18348272otl.3 for ; Mon, 19 Jul 2021 07:24:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:to:references:from:subject:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=7/qq3wyUV7N73BKpIHcRfvtIpGGk0m3CwLVAIa8erWo=; b=i+k6lzbQu/gYTazdC+tDJ+VqdJU6OFUmm3rB+LR3/2M/9mHGl/O662JrlUjlhCJc7e ZiJYreKouyfxkeiODkVVMvE41hTmVEAlG29kukXUrZ8czMj1LYShWI6tH+UNJvVMN3CT aJyhBcrwvQfiOI+nlPUAk9g0yq6Vpa3U7S/PHgQuO5sd9Gi4dD+ECGAZAwq1Xjdksqcs G2LR1m+G4OH60VqMYPePCoYzWde4SJdY/C+zBkr08pfbXPtpyWzEcENPmN8FnOyCClGF OcNw1i6IQbEKmoKfsGdXCPJYdJ8t/SPX1T7m3MADjcJwpocz2qmqSMQx7V/MnXUD5p1X leSA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:to:references:from:subject:message-id :date:user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=7/qq3wyUV7N73BKpIHcRfvtIpGGk0m3CwLVAIa8erWo=; b=VmUiR2Nw60FAgxUONNTrlLp44jDaR/4Ron7XfcVl8DxYFGcIzTjhYqgbagRz2cGWoT cM1g6EmJZv1WnV+Iq/odrbDlVkeFLG2fLXWZURhJePcRGKyiD+twh1AHvXqXugdj5LSA 9z1Wx3bEEkTDjhlx08Te5UbxCHOSdgbdLyDHix56hEfC1/Vp0SSxFhsz+z8qXVj7I2Xs 9Bc40fRHoc3O1BPnvc4JUHHyIgZwx0nyNcQIYKpEbsw4cYBmwN2fNMFb+dTD1Rj47u5u xSCfGLqSYY2rHcNHnrd2uZYawM96Xkk9vk8oVwi2zWJ1QqKlCHVtGygZPSPApNn2dAnI vyjw== X-Gm-Message-State: AOAM530rX13zVJYqo8G626WAPDYikt/txdndTUlrdRr8iwBIG7zlJW9R h25cqbbPpGuwX9EURNEyuz0= X-Google-Smtp-Source: ABdhPJx+VI2LTCuw35AamWFKyfBdlpvyzZmsV1/KxXQqjbQo5sFs3G6o6Fdv92eq+ScsT3IPzd7ANQ== X-Received: by 2002:a9d:638f:: with SMTP id w15mr470201otk.148.1626704686753; Mon, 19 Jul 2021 07:24:46 -0700 (PDT) Received: from server.roeck-us.net ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id 48sm3584391otf.13.2021.07.19.07.24.45 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 19 Jul 2021 07:24:46 -0700 (PDT) To: Akira Tsukamoto , Palmer Dabbelt , Geert Uytterhoeven , Qiu Wenbo , Paul Walmsley , Albert Ou , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org References: <5e1b5d90-5a1e-5e9f-7b92-6c53b8589c2a@gmail.com> From: Guenter Roeck Subject: Re: [PATCH v4 1/1] riscv: __asm_copy_to-from_user: Optimize unaligned memory access and pipeline stall Message-ID: <9a2bf544-2aaa-d175-bc0a-c8bcefd8141a@roeck-us.net> Date: Mon, 19 Jul 2021 07:24:44 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210719_072449_094083_FCF97E69 X-CRM114-Status: GOOD ( 20.58 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: base64 Content-Type: text/plain; charset="utf-8"; Format="flowed" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org T24gNy8xOS8yMSA3OjAwIEFNLCBBa2lyYSBUc3VrYW1vdG8gd3JvdGU6Cj4gCj4gT24gNy8xOS8y MDIxIDEwOjUxIFBNLCBHdWVudGVyIFJvZWNrIHdyb3RlOgo+PiBIaSwKPj4KPj4gT24gNy8xOS8y MSA1OjUzIEFNLCBBa2lyYSBUc3VrYW1vdG8gd3JvdGU6Cj4+Pgo+Pj4gVGhpcyBwYXRjaCB3aWxs IHJlZHVjZSBjcHUgdXNhZ2UgZHJhbWF0aWNhbGx5IGluIGtlcm5lbCBzcGFjZSBlc3BlY2lhbGx5 Cj4+PiBmb3IgYXBwbGljYXRpb24gd2hpY2ggdXNlIHN5cy1jYWxsIHdpdGggbGFyZ2UgYnVmZmVy IHNpemUsIHN1Y2ggYXMKPj4+IG5ldHdvcmsgYXBwbGljYXRpb25zLiBUaGUgbWFpbiByZWFzb24g YmVoaW5kIHRoaXMgaXMgdGhhdCBldmVyeQo+Pj4gdW5hbGlnbmVkIG1lbW9yeSBhY2Nlc3Mgd2ls bCByYWlzZSBleGNlcHRpb25zIGFuZCBzd2l0Y2ggYmV0d2VlbiBzLW1vZGUKPj4+IGFuZCBtLW1v ZGUgY2F1c2luZyBsYXJnZSBvdmVyaGVhZC4KPj4+Cj4+Cj4+IEkgaGFkIHRvIHJldmVydCB0aGUg b3JpZ2luYWwgcGF0Y2ggZnJvbSB0aGUgbWFpbmxpbmUga2VybmVsIHByaW9yIHRvIGFwcGx5aW5n Cj4+IHRoaXMgcGF0Y2guIE9idmlvdXNseSB0aGF0IG1lYW5zIHRoYXQgdGhlcmUgbWF5IGJlIG90 aGVyIGNoYW5nZXMgYWZmZWN0aW5nIHRoZQo+PiBvdXRjb21lLgo+Pgo+PiByaXNjdjY0IGltYWdl cyB3b3JrLCBidXQgcmlzY3YzMiBpbWFnZXMgc3RpbGwgZmFpbCB3aXRoIHRoaXMgcGF0Y2ggYXBw bGllZC4KPj4gVGhlIGVycm9yIGlzIGEgYml0IGRpZmZlcmVudCB0aGFuIGJlZm9yZSwgdGhvdWdo Lgo+Pgo+PiAuLi4KPj4gW8KgwqAgMTEuODk5OTc5XSBSdW4gL3NiaW4vaW5pdCBhcyBpbml0IHBy b2Nlc3MKPj4gW8KgwqAgMTIuMTUyNjY2XSByYW5kb206IGZhc3QgaW5pdCBkb25lCj4+IG1vdW46 IGFwcGxldCBub3QgZm91bmQKPj4gIu+/ve+/ve+/ve+/ve+/vVbvv710OiBhcHBsZXQgbm90IGZv dW5kCj4+IC9iae+/ve+/ve+/ve+/ve+/vVbvv71GLTogYXBwbGV0IG5vdCBmb3VuZAo+PiBtb3Vu OiBhcHBsZXQgbm90IGZvdW5kCj4+IHN3YW9uOiBhcHBsZXQgbm90IGZvdW5kCj4+IGhvc3RuYW1l LUY6IGFwcGxldCBub3QgZm91bmQKPj4KPj4gQWZ0ZXIgdGhpcywgdGhlIGltYWdlIGhhbmdzLgo+ Pgo+PiBGb3IgY29tcGFyaXNvbiwgdGhlIG1haW5saW5lIGtlcm5lbCAodjUuMTQtcmMyKSBmYWls cyBhcyBmb2xsb3dzLgo+Pgo+PiBbwqDCoCAxMC43ODgxMDVdIFJ1biAvc2Jpbi9pbml0IGFzIGlu aXQgcHJvY2Vzcwo+PiBTdGFydGluZyBzeXNsb2dkOiBPSwo+PiBTdGFydGluZyBrbG9nZDogT0sK Pj4gL2V0Yy9pbml0LmQvUzAyc3lzY3RsOiBsaW5lIDY4OiBzeW50YXggZXJyb3I6IEVPRiBpbiBi YWNrcXVvdGUgc3Vic3RpdHV0aW9uCj4+IC9ldGMvaW5pdC5kL1MyMHVyYW5kb206IGxpbmUgMTog c3ludGF4IGVycm9yOiB1bnRlcm1pbmF0ZWQgcXVvdGVkIHN0cmluZwo+PiBTdGFydGluZyBuZXR3 b3JrOiAvYmluL3NoOiBzeW50YXggZXJyb3I6IHVudGVybWluYXRlZCBxdW90ZWQgc3RyaW5nCj4+ IHNlZDogdW5tYXRjaGVkICcvJwo+PiAvYmluL3NoOiBzeW50YXggZXJyb3I6IHVudGVybWluYXRl ZCBxdW90ZWQgc3RyaW5nCj4+IEZBSUwKPj4gL2V0Yy9pbml0LmQvUzU1cnVudGVzdDogbGluZSA0 ODogc3ludGF4IGVycm9yOiBFT0YgaW4gYmFja3F1b3RlIHN1YnN0aXR1dGlvbgo+Pgo+PiBJJ2xs IGJlIGhhcHB5IHRvIHByb3ZpZGUgaW5mb3JtYXRpb24gb24gaG93IHRvIHJlcHJvZHVjZSB0aGUg cHJvYmxlbQo+PiBpZiBuZWVkZWQuIFBsZWFzZSBsZXQgbWUga25vdy4KPiAKPiBZZXMsIEkgZG8g d291bGQgbGlrZSB0byBrbm93IHRoZSBwcm9jZWR1cmUgb2YgYnVpbGQgaW5zdHJ1Y3Rpb24gb2Yg eW91ciBydjMyIGltYWdlLgo+IFRoZW4gSSB3b3VsZCByZXByb2R1Y2UgdGhlIGVycm9yIGFuZCBs b29rIGludG8gaG93IHRvIGZpeCBpdC4KPiAKUGxlYXNlIGhhdmUgYSBsb29rIGF0IGh0dHA6Ly9z ZXJ2ZXIucm9lY2stdXMubmV0L3FlbXUvcmlzY3YzMi8KYW5kIGxldCBtZSBrbm93IGlmIHlvdSBu ZWVkIGFueXRoaW5nIGVsc2UuCgpUaGFua3MsCkd1ZW50ZXIKCl9fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fCmxpbnV4LXJpc2N2IG1haWxpbmcgbGlzdApsaW51 eC1yaXNjdkBsaXN0cy5pbmZyYWRlYWQub3JnCmh0dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21h aWxtYW4vbGlzdGluZm8vbGludXgtcmlzY3YK