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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 BA6E4C47094 for ; Mon, 31 May 2021 06:37:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 96FA7610FC for ; Mon, 31 May 2021 06:37:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230188AbhEaGil (ORCPT ); Mon, 31 May 2021 02:38:41 -0400 Received: from verein.lst.de ([213.95.11.211]:48269 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230070AbhEaGik (ORCPT ); Mon, 31 May 2021 02:38:40 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 4B7F367373; Mon, 31 May 2021 08:36:58 +0200 (CEST) Date: Mon, 31 May 2021 08:36:58 +0200 From: Christoph Hellwig To: palmerdabbelt@google.com Cc: Christoph Hellwig , guoren@kernel.org, Anup Patel , Arnd Bergmann , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-sunxi@lists.linux.dev, guoren@linux.alibaba.com Subject: Re: [PATCH V4 2/2] riscv: Use use_asid_allocator flush TLB Message-ID: <20210531063658.GB1143@lst.de> References: <20210527070903.GA32653@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, May 29, 2021 at 04:42:37PM -0700, palmerdabbelt@google.com wrote: >> >> Also the non-ASID code switches to a global flush once flushing more >> than a single page. It might be worth documenting the tradeoff in the >> code. > > For some reason I thought we'd written this down in the commentary of teh > ISA manual as the suggested huersitic here, but I can't find it so maybe > I'm wrong. If it's actually there it would be good to point that out, > otherwise some documentation seems fine as it'll probably become a tunable > at some point anyway. The real question is why is the heuristic different for the ASID vs non-ASID case? I think that really need a comment. > LGTM. I took the first one as IMO they're really distnict issues, LMK if > you want to re-spin this one or if I should just take what's here. What distinct issue? The fact that the new code is buggy and uses rather non-optimal calling conventions?