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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 59D49C4321D for ; Mon, 20 Aug 2018 23:30:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 022992173D for ; Mon, 20 Aug 2018 23:30:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=sifive.com header.i=@sifive.com header.b="NFWVTb2H" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 022992173D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=sifive.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726787AbeHUCsU (ORCPT ); Mon, 20 Aug 2018 22:48:20 -0400 Received: from mail-pf1-f196.google.com ([209.85.210.196]:44839 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726585AbeHUCsU (ORCPT ); Mon, 20 Aug 2018 22:48:20 -0400 Received: by mail-pf1-f196.google.com with SMTP id k21-v6so7536417pff.11 for ; Mon, 20 Aug 2018 16:30:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sifive.com; s=google; h=date:subject:in-reply-to:cc:from:to:message-id:mime-version :content-transfer-encoding; bh=wVB50HPFIvEh5C1xFtxJ1SV8MXGvqdJD3nLvGKQdLLw=; b=NFWVTb2HH18i3RxrbmEDTgwTfFOFFt8Qoeg/AqyIqNzYvnFeEklqeVdHb4sjZHnC7Q FntmNYFVOpc6oUe3JDQ22thJagPQ2ak+inX6XnphcTZONeF9U2/HAk9G012xrQnaOKHu /C7RMfbss/AMGlB3A0j6+e6M1c8D9YBlSJ5Tqt6yKIg0YpCOlSojx47FPMjsXJo0y9Kw DuSYJet9XpdpgUdS47a2KjjYMaVSPOhGl2d2TEV/lahVoEOYwzOoUy/p8TvvnfdswQtM d9LYY90vz3WFcdrNCXS/DzIPl0zXTgiy6qjsXxbIxVnW0RrfsCqoWy/ZFPct+U+0RFTX zKmw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:subject:in-reply-to:cc:from:to:message-id :mime-version:content-transfer-encoding; bh=wVB50HPFIvEh5C1xFtxJ1SV8MXGvqdJD3nLvGKQdLLw=; b=m9mVD+7ELbUgsa7aBt9C4DkF5GDsgSHrfGYcsIQgxpCIc47v3KWa7Jrc0Zt6aMMqzP HDANE6o79kd7m/1+Q4nfzeuRWTq66F6ahy+RLyV2TXiHs0r3iiHIyujsABPoF2aStwBx CCehIboHPmeYP8WTjH0pulNpfyLMX6ua06xydM2+zeBMDPP76HoBNHXE2+qu+iDxp3Rw KDGB19C4pUrAP0paWRrZop17PfInKCxKIe2t+seXGOoWFFXyoi6rNsngLJAhK3PNks76 vsqaydz/pQ81haqv71i1tUgWr9fAsUvKkp7Do95KB7p2z9ZNHBusMAS/rO26wEuVKRJW lyqQ== X-Gm-Message-State: AOUpUlHh2hL4WZ5xKPExIh0zIGCPtcE+IqGIFZoVNB3XbgyFxr2iOLw7 BMT8nIZFYFejkAjd9Rq41PZoXg== X-Google-Smtp-Source: AA+uWPxw0YjZjM28A6ssJQy60E94AIHRxGhrIqFu8NvLzTfep1VhjHpr2Qr57G5O9x5tMeBYFFP7fg== X-Received: by 2002:a62:234d:: with SMTP id j74-v6mr50137529pfj.106.1534807841082; Mon, 20 Aug 2018 16:30:41 -0700 (PDT) Received: from localhost ([12.206.222.5]) by smtp.gmail.com with ESMTPSA id x80-v6sm20588431pfe.129.2018.08.20.16.30.39 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 20 Aug 2018 16:30:39 -0700 (PDT) Date: Mon, 20 Aug 2018 16:30:39 -0700 (PDT) X-Google-Original-Date: Mon, 20 Aug 2018 16:23:55 PDT (-0700) Subject: Re: [PATCH v3 1/2] RISC-V: Define sys_riscv_flush_icache when SMP=n In-Reply-To: <20180814133922.GC28080@infradead.org> CC: Christoph Hellwig , linux@roeck-us.net, aou@eecs.berkeley.edu, Andrew Waterman , Arnd Bergmann , linux-kernel@vger.kernel.org, linux@dominikbrodowski.net, tklauser@distanz.ch, linux-riscv@lists.infradead.org, dan.carpenter@oracle.com From: Palmer Dabbelt To: Christoph Hellwig Message-ID: Mime-Version: 1.0 (MHng) Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 14 Aug 2018 06:39:23 PDT (-0700), Christoph Hellwig wrote: >> SYSCALL_DEFINE3(riscv_flush_icache, uintptr_t, start, uintptr_t, end, >> uintptr_t, flags) >> { >> +#ifdef CONFIG_SMP >> struct mm_struct *mm = current->mm; >> bool local = (flags & SYS_RISCV_FLUSH_ICACHE_LOCAL) != 0; >> +#endif >> >> /* Check the reserved flags. */ >> if (unlikely(flags & ~SYS_RISCV_FLUSH_ICACHE_ALL)) >> return -EINVAL; >> >> + /* >> + * Without CONFIG_SMP flush_icache_mm is a just a flush_icache_all(), >> + * which generates unused variable warnings all over this function. >> + */ >> +#ifdef CONFIG_SMP >> flush_icache_mm(mm, local); >> +#else >> + flush_icache_all(); >> +#endif > > Eeek. > > Something like an unconditional: > > flush_icache_mm(current->mm, flags & SYS_RISCV_FLUSH_ICACHE_LOCAL); > > should solve those issues. > > Also in the longer run we should turn the !SMP flush_icache_mm stub > into an inline function to solve this problem for all potential > callers. Excepte that flush_icache_mm happens to be a RISC-V specific > API without any other callers. So for now I think the above is what > I'd do, but this area has a lot of room for cleanup. Thanks, that's a lot cleaner. I missed this for the PR, but I'll submit a cleanup patch after RC1.